diff options
Diffstat (limited to '')
| -rw-r--r-- | gc/include/backptr.h | 56 | ||||
| -rw-r--r-- | gc/include/cord.h | 327 | ||||
| -rw-r--r-- | gc/include/ec.h | 70 | ||||
| -rw-r--r-- | gc/include/gc.h | 754 | ||||
| -rw-r--r-- | gc/include/gc_alloc.h | 380 | ||||
| -rw-r--r-- | gc/include/gc_cpp.h | 290 | ||||
| -rw-r--r-- | gc/include/gc_inl.h | 103 | ||||
| -rw-r--r-- | gc/include/gc_inline.h | 1 | ||||
| -rw-r--r-- | gc/include/gc_typed.h | 91 | ||||
| -rw-r--r-- | gc/include/javaxfc.h | 41 | ||||
| -rw-r--r-- | gc/include/leak_detector.h | 7 | ||||
| -rw-r--r-- | gc/include/new_gc_alloc.h | 456 | ||||
| -rw-r--r-- | gc/include/private/cord_pos.h | 118 | ||||
| -rw-r--r-- | gc/include/private/gc_hdrs.h | 135 | ||||
| -rw-r--r-- | gc/include/private/gc_priv.h | 1748 | ||||
| -rw-r--r-- | gc/include/private/gcconfig.h | 1099 | ||||
| -rw-r--r-- | gc/include/weakpointer.h | 221 |
17 files changed, 5897 insertions, 0 deletions
diff --git a/gc/include/backptr.h b/gc/include/backptr.h new file mode 100644 index 0000000..d34224e --- /dev/null +++ b/gc/include/backptr.h @@ -0,0 +1,56 @@ +/* + * This is a simple API to implement pointer back tracing, i.e. + * to answer questions such as "who is pointing to this" or + * "why is this object being retained by the collector" + * + * This API assumes that we have an ANSI C compiler. + * + * Most of these calls yield useful information on only after + * a garbage collection. Usually the client will first force + * a full collection and then gather information, preferably + * before much intervening allocation. + * + * The implementation of the interface is only about 99.9999% + * correct. It is intended to be good enough for profiling, + * but is not intended to be used with production code. + * + * Results are likely to be much more useful if all allocation is + * accomplished through the debugging allocators. + * + * The implementation idea is due to A. Demers. + */ + +/* Store information about the object referencing dest in *base_p */ +/* and *offset_p. */ +/* If multiple objects or roots point to dest, the one reported */ +/* will be the last on used by the garbage collector to trace the */ +/* object. */ +/* source is root ==> *base_p = address, *offset_p = 0 */ +/* source is heap object ==> *base_p != 0, *offset_p = offset */ +/* Returns 1 on success, 0 if source couldn't be determined. */ +/* Dest can be any address within a heap object. */ +typedef enum { GC_UNREFERENCED, /* No refence info available. */ + GC_NO_SPACE, /* Dest not allocated with debug alloc */ + GC_REFD_FROM_ROOT, /* Referenced directly by root *base_p */ + GC_REFD_FROM_HEAP, /* Referenced from another heap obj. */ + GC_FINALIZER_REFD /* Finalizable and hence accessible. */ +} GC_ref_kind; + +GC_ref_kind GC_get_back_ptr_info(void *dest, void **base_p, size_t *offset_p); + +/* Generate a random heap address. */ +/* The resulting address is in the heap, but */ +/* not necessarily inside a valid object. */ +void * GC_generate_random_heap_address(void); + +/* Generate a random address inside a valid marked heap object. */ +void * GC_generate_random_valid_address(void); + +/* Force a garbage collection and generate a backtrace from a */ +/* random heap address. */ +/* This uses the GC logging mechanism (GC_printf) to produce */ +/* output. It can often be called from a debugger. The */ +/* source in dbg_mlc.c also serves as a sample client. */ +void GC_generate_random_backtrace(void); + + diff --git a/gc/include/cord.h b/gc/include/cord.h new file mode 100644 index 0000000..584112f --- /dev/null +++ b/gc/include/cord.h @@ -0,0 +1,327 @@ +/* + * Copyright (c) 1993-1994 by Xerox Corporation. All rights reserved. + * + * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED + * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + * + * Permission is hereby granted to use or copy this program + * for any purpose, provided the above notices are retained on all copies. + * Permission to modify the code and to distribute modified code is granted, + * provided the above notices are retained, and a notice that the code was + * modified is included with the above copyright notice. + * + * Author: Hans-J. Boehm (boehm@parc.xerox.com) + */ +/* Boehm, October 5, 1995 4:20 pm PDT */ + +/* + * Cords are immutable character strings. A number of operations + * on long cords are much more efficient than their strings.h counterpart. + * In particular, concatenation takes constant time independent of the length + * of the arguments. (Cords are represented as trees, with internal + * nodes representing concatenation and leaves consisting of either C + * strings or a functional description of the string.) + * + * The following are reasonable applications of cords. They would perform + * unacceptably if C strings were used: + * - A compiler that produces assembly language output by repeatedly + * concatenating instructions onto a cord representing the output file. + * - A text editor that converts the input file to a cord, and then + * performs editing operations by producing a new cord representing + * the file after echa character change (and keeping the old ones in an + * edit history) + * + * For optimal performance, cords should be built by + * concatenating short sections. + * This interface is designed for maximum compatibility with C strings. + * ASCII NUL characters may be embedded in cords using CORD_from_fn. + * This is handled correctly, but CORD_to_char_star will produce a string + * with embedded NULs when given such a cord. + * + * This interface is fairly big, largely for performance reasons. + * The most basic constants and functions: + * + * CORD - the type fo a cord; + * CORD_EMPTY - empty cord; + * CORD_len(cord) - length of a cord; + * CORD_cat(cord1,cord2) - concatenation of two cords; + * CORD_substr(cord, start, len) - substring (or subcord); + * CORD_pos i; CORD_FOR(i, cord) { ... CORD_pos_fetch(i) ... } - + * examine each character in a cord. CORD_pos_fetch(i) is the char. + * CORD_fetch(int i) - Retrieve i'th character (slowly). + * CORD_cmp(cord1, cord2) - compare two cords. + * CORD_from_file(FILE * f) - turn a read-only file into a cord. + * CORD_to_char_star(cord) - convert to C string. + * (Non-NULL C constant strings are cords.) + * CORD_printf (etc.) - cord version of printf. Use %r for cords. + */ +# ifndef CORD_H + +# define CORD_H +# include <stddef.h> +# include <stdio.h> +/* Cords have type const char *. This is cheating quite a bit, and not */ +/* 100% portable. But it means that nonempty character string */ +/* constants may be used as cords directly, provided the string is */ +/* never modified in place. The empty cord is represented by, and */ +/* can be written as, 0. */ + +typedef const char * CORD; + +/* An empty cord is always represented as nil */ +# define CORD_EMPTY 0 + +/* Is a nonempty cord represented as a C string? */ +#define CORD_IS_STRING(s) (*(s) != '\0') + +/* Concatenate two cords. If the arguments are C strings, they may */ +/* not be subsequently altered. */ +CORD CORD_cat(CORD x, CORD y); + +/* Concatenate a cord and a C string with known length. Except for the */ +/* empty string case, this is a special case of CORD_cat. Since the */ +/* length is known, it can be faster. */ +/* The string y is shared with the resulting CORD. Hence it should */ +/* not be altered by the caller. */ +CORD CORD_cat_char_star(CORD x, const char * y, size_t leny); + +/* Compute the length of a cord */ +size_t CORD_len(CORD x); + +/* Cords may be represented by functions defining the ith character */ +typedef char (* CORD_fn)(size_t i, void * client_data); + +/* Turn a functional description into a cord. */ +CORD CORD_from_fn(CORD_fn fn, void * client_data, size_t len); + +/* Return the substring (subcord really) of x with length at most n, */ +/* starting at position i. (The initial character has position 0.) */ +CORD CORD_substr(CORD x, size_t i, size_t n); + +/* Return the argument, but rebalanced to allow more efficient */ +/* character retrieval, substring operations, and comparisons. */ +/* This is useful only for cords that were built using repeated */ +/* concatenation. Guarantees log time access to the result, unless */ +/* x was obtained through a large number of repeated substring ops */ +/* or the embedded functional descriptions take longer to evaluate. */ +/* May reallocate significant parts of the cord. The argument is not */ +/* modified; only the result is balanced. */ +CORD CORD_balance(CORD x); + +/* The following traverse a cord by applying a function to each */ +/* character. This is occasionally appropriate, especially where */ +/* speed is crucial. But, since C doesn't have nested functions, */ +/* clients of this sort of traversal are clumsy to write. Consider */ +/* the functions that operate on cord positions instead. */ + +/* Function to iteratively apply to individual characters in cord. */ +typedef int (* CORD_iter_fn)(char c, void * client_data); + +/* Function to apply to substrings of a cord. Each substring is a */ +/* a C character string, not a general cord. */ +typedef int (* CORD_batched_iter_fn)(const char * s, void * client_data); +# define CORD_NO_FN ((CORD_batched_iter_fn)0) + +/* Apply f1 to each character in the cord, in ascending order, */ +/* starting at position i. If */ +/* f2 is not CORD_NO_FN, then multiple calls to f1 may be replaced by */ +/* a single call to f2. The parameter f2 is provided only to allow */ +/* some optimization by the client. This terminates when the right */ +/* end of this string is reached, or when f1 or f2 return != 0. In the */ +/* latter case CORD_iter returns != 0. Otherwise it returns 0. */ +/* The specified value of i must be < CORD_len(x). */ +int CORD_iter5(CORD x, size_t i, CORD_iter_fn f1, + CORD_batched_iter_fn f2, void * client_data); + +/* A simpler version that starts at 0, and without f2: */ +int CORD_iter(CORD x, CORD_iter_fn f1, void * client_data); +# define CORD_iter(x, f1, cd) CORD_iter5(x, 0, f1, CORD_NO_FN, cd) + +/* Similar to CORD_iter5, but end-to-beginning. No provisions for */ +/* CORD_batched_iter_fn. */ +int CORD_riter4(CORD x, size_t i, CORD_iter_fn f1, void * client_data); + +/* A simpler version that starts at the end: */ +int CORD_riter(CORD x, CORD_iter_fn f1, void * client_data); + +/* Functions that operate on cord positions. The easy way to traverse */ +/* cords. A cord position is logically a pair consisting of a cord */ +/* and an index into that cord. But it is much faster to retrieve a */ +/* charcter based on a position than on an index. Unfortunately, */ +/* positions are big (order of a few 100 bytes), so allocate them with */ +/* caution. */ +/* Things in cord_pos.h should be treated as opaque, except as */ +/* described below. Also note that */ +/* CORD_pos_fetch, CORD_next and CORD_prev have both macro and function */ +/* definitions. The former may evaluate their argument more than once. */ +# include "private/cord_pos.h" + +/* + Visible definitions from above: + + typedef <OPAQUE but fairly big> CORD_pos[1]; + + * Extract the cord from a position: + CORD CORD_pos_to_cord(CORD_pos p); + + * Extract the current index from a position: + size_t CORD_pos_to_index(CORD_pos p); + + * Fetch the character located at the given position: + char CORD_pos_fetch(CORD_pos p); + + * Initialize the position to refer to the given cord and index. + * Note that this is the most expensive function on positions: + void CORD_set_pos(CORD_pos p, CORD x, size_t i); + + * Advance the position to the next character. + * P must be initialized and valid. + * Invalidates p if past end: + void CORD_next(CORD_pos p); + + * Move the position to the preceding character. + * P must be initialized and valid. + * Invalidates p if past beginning: + void CORD_prev(CORD_pos p); + + * Is the position valid, i.e. inside the cord? + int CORD_pos_valid(CORD_pos p); +*/ +# define CORD_FOR(pos, cord) \ + for (CORD_set_pos(pos, cord, 0); CORD_pos_valid(pos); CORD_next(pos)) + + +/* An out of memory handler to call. May be supplied by client. */ +/* Must not return. */ +extern void (* CORD_oom_fn)(void); + +/* Dump the representation of x to stdout in an implementation defined */ +/* manner. Intended for debugging only. */ +void CORD_dump(CORD x); + +/* The following could easily be implemented by the client. They are */ +/* provided in cordxtra.c for convenience. */ + +/* Concatenate a character to the end of a cord. */ +CORD CORD_cat_char(CORD x, char c); + +/* Concatenate n cords. */ +CORD CORD_catn(int n, /* CORD */ ...); + +/* Return the character in CORD_substr(x, i, 1) */ +char CORD_fetch(CORD x, size_t i); + +/* Return < 0, 0, or > 0, depending on whether x < y, x = y, x > y */ +int CORD_cmp(CORD x, CORD y); + +/* A generalization that takes both starting positions for the */ +/* comparison, and a limit on the number of characters to be compared. */ +int CORD_ncmp(CORD x, size_t x_start, CORD y, size_t y_start, size_t len); + +/* Find the first occurrence of s in x at position start or later. */ +/* Return the position of the first character of s in x, or */ +/* CORD_NOT_FOUND if there is none. */ +size_t CORD_str(CORD x, size_t start, CORD s); + +/* Return a cord consisting of i copies of (possibly NUL) c. Dangerous */ +/* in conjunction with CORD_to_char_star. */ +/* The resulting representation takes constant space, independent of i. */ +CORD CORD_chars(char c, size_t i); +# define CORD_nul(i) CORD_chars('\0', (i)) + +/* Turn a file into cord. The file must be seekable. Its contents */ +/* must remain constant. The file may be accessed as an immediate */ +/* result of this call and/or as a result of subsequent accesses to */ +/* the cord. Short files are likely to be immediately read, but */ +/* long files are likely to be read on demand, possibly relying on */ +/* stdio for buffering. */ +/* We must have exclusive access to the descriptor f, i.e. we may */ +/* read it at any time, and expect the file pointer to be */ +/* where we left it. Normally this should be invoked as */ +/* CORD_from_file(fopen(...)) */ +/* CORD_from_file arranges to close the file descriptor when it is no */ +/* longer needed (e.g. when the result becomes inaccessible). */ +/* The file f must be such that ftell reflects the actual character */ +/* position in the file, i.e. the number of characters that can be */ +/* or were read with fread. On UNIX systems this is always true. On */ +/* MS Windows systems, f must be opened in binary mode. */ +CORD CORD_from_file(FILE * f); + +/* Equivalent to the above, except that the entire file will be read */ +/* and the file pointer will be closed immediately. */ +/* The binary mode restriction from above does not apply. */ +CORD CORD_from_file_eager(FILE * f); + +/* Equivalent to the above, except that the file will be read on demand.*/ +/* The binary mode restriction applies. */ +CORD CORD_from_file_lazy(FILE * f); + +/* Turn a cord into a C string. The result shares no structure with */ +/* x, and is thus modifiable. */ +char * CORD_to_char_star(CORD x); + +/* Turn a C string into a CORD. The C string is copied, and so may */ +/* subsequently be modified. */ +CORD CORD_from_char_star(const char *s); + +/* Identical to the above, but the result may share structure with */ +/* the argument and is thus not modifiable. */ +const char * CORD_to_const_char_star(CORD x); + +/* Write a cord to a file, starting at the current position. No */ +/* trailing NULs are newlines are added. */ +/* Returns EOF if a write error occurs, 1 otherwise. */ +int CORD_put(CORD x, FILE * f); + +/* "Not found" result for the following two functions. */ +# define CORD_NOT_FOUND ((size_t)(-1)) + +/* A vague analog of strchr. Returns the position (an integer, not */ +/* a pointer) of the first occurrence of (char) c inside x at position */ +/* i or later. The value i must be < CORD_len(x). */ +size_t CORD_chr(CORD x, size_t i, int c); + +/* A vague analog of strrchr. Returns index of the last occurrence */ +/* of (char) c inside x at position i or earlier. The value i */ +/* must be < CORD_len(x). */ +size_t CORD_rchr(CORD x, size_t i, int c); + + +/* The following are also not primitive, but are implemented in */ +/* cordprnt.c. They provide functionality similar to the ANSI C */ +/* functions with corresponding names, but with the following */ +/* additions and changes: */ +/* 1. A %r conversion specification specifies a CORD argument. Field */ +/* width, precision, etc. have the same semantics as for %s. */ +/* (Note that %c,%C, and %S were already taken.) */ +/* 2. The format string is represented as a CORD. */ +/* 3. CORD_sprintf and CORD_vsprintf assign the result through the 1st */ /* argument. Unlike their ANSI C versions, there is no need to guess */ +/* the correct buffer size. */ +/* 4. Most of the conversions are implement through the native */ +/* vsprintf. Hence they are usually no faster, and */ +/* idiosyncracies of the native printf are preserved. However, */ +/* CORD arguments to CORD_sprintf and CORD_vsprintf are NOT copied; */ +/* the result shares the original structure. This may make them */ +/* very efficient in some unusual applications. */ +/* The format string is copied. */ +/* All functions return the number of characters generated or -1 on */ +/* error. This complies with the ANSI standard, but is inconsistent */ +/* with some older implementations of sprintf. */ + +/* The implementation of these is probably less portable than the rest */ +/* of this package. */ + +#ifndef CORD_NO_IO + +#include <stdarg.h> + +int CORD_sprintf(CORD * out, CORD format, ...); +int CORD_vsprintf(CORD * out, CORD format, va_list args); +int CORD_fprintf(FILE * f, CORD format, ...); +int CORD_vfprintf(FILE * f, CORD format, va_list args); +int CORD_printf(CORD format, ...); +int CORD_vprintf(CORD format, va_list args); + +#endif /* CORD_NO_IO */ + +# endif /* CORD_H */ diff --git a/gc/include/ec.h b/gc/include/ec.h new file mode 100644 index 0000000..c829b83 --- /dev/null +++ b/gc/include/ec.h @@ -0,0 +1,70 @@ +# ifndef EC_H +# define EC_H + +# ifndef CORD_H +# include "cord.h" +# endif + +/* Extensible cords are strings that may be destructively appended to. */ +/* They allow fast construction of cords from characters that are */ +/* being read from a stream. */ +/* + * A client might look like: + * + * { + * CORD_ec x; + * CORD result; + * char c; + * FILE *f; + * + * ... + * CORD_ec_init(x); + * while(...) { + * c = getc(f); + * ... + * CORD_ec_append(x, c); + * } + * result = CORD_balance(CORD_ec_to_cord(x)); + * + * If a C string is desired as the final result, the call to CORD_balance + * may be replaced by a call to CORD_to_char_star. + */ + +# ifndef CORD_BUFSZ +# define CORD_BUFSZ 128 +# endif + +typedef struct CORD_ec_struct { + CORD ec_cord; + char * ec_bufptr; + char ec_buf[CORD_BUFSZ+1]; +} CORD_ec[1]; + +/* This structure represents the concatenation of ec_cord with */ +/* ec_buf[0 ... (ec_bufptr-ec_buf-1)] */ + +/* Flush the buffer part of the extended chord into ec_cord. */ +/* Note that this is almost the only real function, and it is */ +/* implemented in 6 lines in cordxtra.c */ +void CORD_ec_flush_buf(CORD_ec x); + +/* Convert an extensible cord to a cord. */ +# define CORD_ec_to_cord(x) (CORD_ec_flush_buf(x), (x)[0].ec_cord) + +/* Initialize an extensible cord. */ +# define CORD_ec_init(x) ((x)[0].ec_cord = 0, (x)[0].ec_bufptr = (x)[0].ec_buf) + +/* Append a character to an extensible cord. */ +# define CORD_ec_append(x, c) \ + { \ + if ((x)[0].ec_bufptr == (x)[0].ec_buf + CORD_BUFSZ) { \ + CORD_ec_flush_buf(x); \ + } \ + *((x)[0].ec_bufptr)++ = (c); \ + } + +/* Append a cord to an extensible cord. Structure remains shared with */ +/* original. */ +void CORD_ec_append_cord(CORD_ec x, CORD s); + +# endif /* EC_H */ diff --git a/gc/include/gc.h b/gc/include/gc.h new file mode 100644 index 0000000..3061409 --- /dev/null +++ b/gc/include/gc.h @@ -0,0 +1,754 @@ +/* + * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers + * Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved. + * Copyright 1996 by Silicon Graphics. All rights reserved. + * + * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED + * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + * + * Permission is hereby granted to use or copy this program + * for any purpose, provided the above notices are retained on all copies. + * Permission to modify the code and to distribute modified code is granted, + * provided the above notices are retained, and a notice that the code was + * modified is included with the above copyright notice. + */ + +/* + * Note that this defines a large number of tuning hooks, which can + * safely be ignored in nearly all cases. For normal use it suffices + * to call only GC_MALLOC and perhaps GC_REALLOC. + * For better performance, also look at GC_MALLOC_ATOMIC, and + * GC_enable_incremental. If you need an action to be performed + * immediately before an object is collected, look at GC_register_finalizer. + * If you are using Solaris threads, look at the end of this file. + * Everything else is best ignored unless you encounter performance + * problems. + */ + +#ifndef _GC_H + +# define _GC_H +# define __GC +# include <stddef.h> + +#if defined(__CYGWIN32__) && defined(GC_USE_DLL) +#include "libgc_globals.h" +#endif + +#if defined(_MSC_VER) && defined(_DLL) +# ifdef GC_BUILD +# define GC_API __declspec(dllexport) +# else +# define GC_API __declspec(dllimport) +# endif +#endif + +#if defined(__WATCOMC__) && defined(GC_DLL) +# ifdef GC_BUILD +# define GC_API extern __declspec(dllexport) +# else +# define GC_API extern __declspec(dllimport) +# endif +#endif + +#ifndef GC_API +#define GC_API extern +#endif + +# if defined(__STDC__) || defined(__cplusplus) +# define GC_PROTO(args) args + typedef void * GC_PTR; +# else +# define GC_PROTO(args) () + typedef char * GC_PTR; +# endif + +# ifdef __cplusplus + extern "C" { +# endif + + +/* Define word and signed_word to be unsigned and signed types of the */ +/* size as char * or void *. There seems to be no way to do this */ +/* even semi-portably. The following is probably no better/worse */ +/* than almost anything else. */ +/* The ANSI standard suggests that size_t and ptr_diff_t might be */ +/* better choices. But those appear to have incorrect definitions */ +/* on may systems. Notably "typedef int size_t" seems to be both */ +/* frequent and WRONG. */ +typedef unsigned long GC_word; +typedef long GC_signed_word; + +/* Public read-only variables */ + +GC_API GC_word GC_gc_no;/* Counter incremented per collection. */ + /* Includes empty GCs at startup. */ + + +/* Public R/W variables */ + +GC_API GC_PTR (*GC_oom_fn) GC_PROTO((size_t bytes_requested)); + /* When there is insufficient memory to satisfy */ + /* an allocation request, we return */ + /* (*GC_oom_fn)(). By default this just */ + /* returns 0. */ + /* If it returns, it must return 0 or a valid */ + /* pointer to a previously allocated heap */ + /* object. */ + +GC_API int GC_find_leak; + /* Do not actually garbage collect, but simply */ + /* report inaccessible memory that was not */ + /* deallocated with GC_free. Initial value */ + /* is determined by FIND_LEAK macro. */ + +GC_API int GC_quiet; /* Disable statistics output. Only matters if */ + /* collector has been compiled with statistics */ + /* enabled. This involves a performance cost, */ + /* and is thus not the default. */ + +GC_API int GC_finalize_on_demand; + /* If nonzero, finalizers will only be run in */ + /* response to an eplit GC_invoke_finalizers */ + /* call. The default is determined by whether */ + /* the FINALIZE_ON_DEMAND macro is defined */ + /* when the collector is built. */ + +GC_API int GC_java_finalization; + /* Mark objects reachable from finalizable */ + /* objects in a separate postpass. This makes */ + /* it a bit safer to use non-topologically- */ + /* ordered finalization. Default value is */ + /* determined by JAVA_FINALIZATION macro. */ + +GC_API int GC_dont_gc; /* Dont collect unless explicitly requested, e.g. */ + /* because it's not safe. */ + +GC_API int GC_dont_expand; + /* Dont expand heap unless explicitly requested */ + /* or forced to. */ + +GC_API int GC_full_freq; /* Number of partial collections between */ + /* full collections. Matters only if */ + /* GC_incremental is set. */ + +GC_API GC_word GC_non_gc_bytes; + /* Bytes not considered candidates for collection. */ + /* Used only to control scheduling of collections. */ + +GC_API GC_word GC_free_space_divisor; + /* We try to make sure that we allocate at */ + /* least N/GC_free_space_divisor bytes between */ + /* collections, where N is the heap size plus */ + /* a rough estimate of the root set size. */ + /* Initially, GC_free_space_divisor = 4. */ + /* Increasing its value will use less space */ + /* but more collection time. Decreasing it */ + /* will appreciably decrease collection time */ + /* at the expense of space. */ + /* GC_free_space_divisor = 1 will effectively */ + /* disable collections. */ + +GC_API GC_word GC_max_retries; + /* The maximum number of GCs attempted before */ + /* reporting out of memory after heap */ + /* expansion fails. Initially 0. */ + + +GC_API char *GC_stackbottom; /* Cool end of user stack. */ + /* May be set in the client prior to */ + /* calling any GC_ routines. This */ + /* avoids some overhead, and */ + /* potentially some signals that can */ + /* confuse debuggers. Otherwise the */ + /* collector attempts to set it */ + /* automatically. */ + /* For multithreaded code, this is the */ + /* cold end of the stack for the */ + /* primordial thread. */ + +/* Public procedures */ +/* + * general purpose allocation routines, with roughly malloc calling conv. + * The atomic versions promise that no relevant pointers are contained + * in the object. The nonatomic versions guarantee that the new object + * is cleared. GC_malloc_stubborn promises that no changes to the object + * will occur after GC_end_stubborn_change has been called on the + * result of GC_malloc_stubborn. GC_malloc_uncollectable allocates an object + * that is scanned for pointers to collectable objects, but is not itself + * collectable. GC_malloc_uncollectable and GC_free called on the resulting + * object implicitly update GC_non_gc_bytes appropriately. + */ +GC_API GC_PTR GC_malloc GC_PROTO((size_t size_in_bytes)); +GC_API GC_PTR GC_malloc_atomic GC_PROTO((size_t size_in_bytes)); +GC_API GC_PTR GC_malloc_uncollectable GC_PROTO((size_t size_in_bytes)); +GC_API GC_PTR GC_malloc_stubborn GC_PROTO((size_t size_in_bytes)); + +/* The following is only defined if the library has been suitably */ +/* compiled: */ +GC_API GC_PTR GC_malloc_atomic_uncollectable GC_PROTO((size_t size_in_bytes)); + +/* Explicitly deallocate an object. Dangerous if used incorrectly. */ +/* Requires a pointer to the base of an object. */ +/* If the argument is stubborn, it should not be changeable when freed. */ +/* An object should not be enable for finalization when it is */ +/* explicitly deallocated. */ +/* GC_free(0) is a no-op, as required by ANSI C for free. */ +GC_API void GC_free GC_PROTO((GC_PTR object_addr)); + +/* + * Stubborn objects may be changed only if the collector is explicitly informed. + * The collector is implicitly informed of coming change when such + * an object is first allocated. The following routines inform the + * collector that an object will no longer be changed, or that it will + * once again be changed. Only nonNIL pointer stores into the object + * are considered to be changes. The argument to GC_end_stubborn_change + * must be exacly the value returned by GC_malloc_stubborn or passed to + * GC_change_stubborn. (In the second case it may be an interior pointer + * within 512 bytes of the beginning of the objects.) + * There is a performance penalty for allowing more than + * one stubborn object to be changed at once, but it is acceptable to + * do so. The same applies to dropping stubborn objects that are still + * changeable. + */ +GC_API void GC_change_stubborn GC_PROTO((GC_PTR)); +GC_API void GC_end_stubborn_change GC_PROTO((GC_PTR)); + +/* Return a pointer to the base (lowest address) of an object given */ +/* a pointer to a location within the object. */ +/* Return 0 if displaced_pointer doesn't point to within a valid */ +/* object. */ +GC_API GC_PTR GC_base GC_PROTO((GC_PTR displaced_pointer)); + +/* Given a pointer to the base of an object, return its size in bytes. */ +/* The returned size may be slightly larger than what was originally */ +/* requested. */ +GC_API size_t GC_size GC_PROTO((GC_PTR object_addr)); + +/* For compatibility with C library. This is occasionally faster than */ +/* a malloc followed by a bcopy. But if you rely on that, either here */ +/* or with the standard C library, your code is broken. In my */ +/* opinion, it shouldn't have been invented, but now we're stuck. -HB */ +/* The resulting object has the same kind as the original. */ +/* If the argument is stubborn, the result will have changes enabled. */ +/* It is an error to have changes enabled for the original object. */ +/* Follows ANSI comventions for NULL old_object. */ +GC_API GC_PTR GC_realloc + GC_PROTO((GC_PTR old_object, size_t new_size_in_bytes)); + +/* Explicitly increase the heap size. */ +/* Returns 0 on failure, 1 on success. */ +GC_API int GC_expand_hp GC_PROTO((size_t number_of_bytes)); + +/* Limit the heap size to n bytes. Useful when you're debugging, */ +/* especially on systems that don't handle running out of memory well. */ +/* n == 0 ==> unbounded. This is the default. */ +GC_API void GC_set_max_heap_size GC_PROTO((GC_word n)); + +/* Inform the collector that a certain section of statically allocated */ +/* memory contains no pointers to garbage collected memory. Thus it */ +/* need not be scanned. This is sometimes important if the application */ +/* maps large read/write files into the address space, which could be */ +/* mistaken for dynamic library data segments on some systems. */ +GC_API void GC_exclude_static_roots GC_PROTO((GC_PTR start, GC_PTR finish)); + +/* Clear the set of root segments. Wizards only. */ +GC_API void GC_clear_roots GC_PROTO((void)); + +/* Add a root segment. Wizards only. */ +GC_API void GC_add_roots GC_PROTO((char * low_address, + char * high_address_plus_1)); + +/* Add a displacement to the set of those considered valid by the */ +/* collector. GC_register_displacement(n) means that if p was returned */ +/* by GC_malloc, then (char *)p + n will be considered to be a valid */ +/* pointer to n. N must be small and less than the size of p. */ +/* (All pointers to the interior of objects from the stack are */ +/* considered valid in any case. This applies to heap objects and */ +/* static data.) */ +/* Preferably, this should be called before any other GC procedures. */ +/* Calling it later adds to the probability of excess memory */ +/* retention. */ +/* This is a no-op if the collector was compiled with recognition of */ +/* arbitrary interior pointers enabled, which is now the default. */ +GC_API void GC_register_displacement GC_PROTO((GC_word n)); + +/* The following version should be used if any debugging allocation is */ +/* being done. */ +GC_API void GC_debug_register_displacement GC_PROTO((GC_word n)); + +/* Explicitly trigger a full, world-stop collection. */ +GC_API void GC_gcollect GC_PROTO((void)); + +/* Trigger a full world-stopped collection. Abort the collection if */ +/* and when stop_func returns a nonzero value. Stop_func will be */ +/* called frequently, and should be reasonably fast. This works even */ +/* if virtual dirty bits, and hence incremental collection is not */ +/* available for this architecture. Collections can be aborted faster */ +/* than normal pause times for incremental collection. However, */ +/* aborted collections do no useful work; the next collection needs */ +/* to start from the beginning. */ +/* Return 0 if the collection was aborted, 1 if it succeeded. */ +typedef int (* GC_stop_func) GC_PROTO((void)); +GC_API int GC_try_to_collect GC_PROTO((GC_stop_func stop_func)); + +/* Return the number of bytes in the heap. Excludes collector private */ +/* data structures. Includes empty blocks and fragmentation loss. */ +/* Includes some pages that were allocated but never written. */ +GC_API size_t GC_get_heap_size GC_PROTO((void)); + +/* Return the number of bytes allocated since the last collection. */ +GC_API size_t GC_get_bytes_since_gc GC_PROTO((void)); + +/* Enable incremental/generational collection. */ +/* Not advisable unless dirty bits are */ +/* available or most heap objects are */ +/* pointerfree(atomic) or immutable. */ +/* Don't use in leak finding mode. */ +/* Ignored if GC_dont_gc is true. */ +GC_API void GC_enable_incremental GC_PROTO((void)); + +/* Perform some garbage collection work, if appropriate. */ +/* Return 0 if there is no more work to be done. */ +/* Typically performs an amount of work corresponding roughly */ +/* to marking from one page. May do more work if further */ +/* progress requires it, e.g. if incremental collection is */ +/* disabled. It is reasonable to call this in a wait loop */ +/* until it returns 0. */ +GC_API int GC_collect_a_little GC_PROTO((void)); + +/* Allocate an object of size lb bytes. The client guarantees that */ +/* as long as the object is live, it will be referenced by a pointer */ +/* that points to somewhere within the first 256 bytes of the object. */ +/* (This should normally be declared volatile to prevent the compiler */ +/* from invalidating this assertion.) This routine is only useful */ +/* if a large array is being allocated. It reduces the chance of */ +/* accidentally retaining such an array as a result of scanning an */ +/* integer that happens to be an address inside the array. (Actually, */ +/* it reduces the chance of the allocator not finding space for such */ +/* an array, since it will try hard to avoid introducing such a false */ +/* reference.) On a SunOS 4.X or MS Windows system this is recommended */ +/* for arrays likely to be larger than 100K or so. For other systems, */ +/* or if the collector is not configured to recognize all interior */ +/* pointers, the threshold is normally much higher. */ +GC_API GC_PTR GC_malloc_ignore_off_page GC_PROTO((size_t lb)); +GC_API GC_PTR GC_malloc_atomic_ignore_off_page GC_PROTO((size_t lb)); + +#if defined(__sgi) && !defined(__GNUC__) && _COMPILER_VERSION >= 720 +# define GC_ADD_CALLER +# define GC_RETURN_ADDR (GC_word)__return_address +#endif + +#ifdef GC_ADD_CALLER +# define GC_EXTRAS GC_RETURN_ADDR, __FILE__, __LINE__ +# define GC_EXTRA_PARAMS GC_word ra, char * descr_string, int descr_int +#else +# define GC_EXTRAS __FILE__, __LINE__ +# define GC_EXTRA_PARAMS char * descr_string, int descr_int +#endif + +/* Debugging (annotated) allocation. GC_gcollect will check */ +/* objects allocated in this way for overwrites, etc. */ +GC_API GC_PTR GC_debug_malloc + GC_PROTO((size_t size_in_bytes, GC_EXTRA_PARAMS)); +GC_API GC_PTR GC_debug_malloc_atomic + GC_PROTO((size_t size_in_bytes, GC_EXTRA_PARAMS)); +GC_API GC_PTR GC_debug_malloc_uncollectable + GC_PROTO((size_t size_in_bytes, GC_EXTRA_PARAMS)); +GC_API GC_PTR GC_debug_malloc_stubborn + GC_PROTO((size_t size_in_bytes, GC_EXTRA_PARAMS)); +GC_API void GC_debug_free GC_PROTO((GC_PTR object_addr)); +GC_API GC_PTR GC_debug_realloc + GC_PROTO((GC_PTR old_object, size_t new_size_in_bytes, + GC_EXTRA_PARAMS)); + +GC_API void GC_debug_change_stubborn GC_PROTO((GC_PTR)); +GC_API void GC_debug_end_stubborn_change GC_PROTO((GC_PTR)); +# ifdef GC_DEBUG +# define GC_MALLOC(sz) GC_debug_malloc(sz, GC_EXTRAS) +# define GC_MALLOC_ATOMIC(sz) GC_debug_malloc_atomic(sz, GC_EXTRAS) +# define GC_MALLOC_UNCOLLECTABLE(sz) GC_debug_malloc_uncollectable(sz, \ + GC_EXTRAS) +# define GC_REALLOC(old, sz) GC_debug_realloc(old, sz, GC_EXTRAS) +# define GC_FREE(p) GC_debug_free(p) +# define GC_REGISTER_FINALIZER(p, f, d, of, od) \ + GC_debug_register_finalizer(p, f, d, of, od) +# define GC_REGISTER_FINALIZER_IGNORE_SELF(p, f, d, of, od) \ + GC_debug_register_finalizer_ignore_self(p, f, d, of, od) +# define GC_MALLOC_STUBBORN(sz) GC_debug_malloc_stubborn(sz, GC_EXTRAS); +# define GC_CHANGE_STUBBORN(p) GC_debug_change_stubborn(p) +# define GC_END_STUBBORN_CHANGE(p) GC_debug_end_stubborn_change(p) +# define GC_GENERAL_REGISTER_DISAPPEARING_LINK(link, obj) \ + GC_general_register_disappearing_link(link, GC_base(obj)) +# define GC_REGISTER_DISPLACEMENT(n) GC_debug_register_displacement(n) +# else +# define GC_MALLOC(sz) GC_malloc(sz) +# define GC_MALLOC_ATOMIC(sz) GC_malloc_atomic(sz) +# define GC_MALLOC_UNCOLLECTABLE(sz) GC_malloc_uncollectable(sz) +# define GC_REALLOC(old, sz) GC_realloc(old, sz) +# define GC_FREE(p) GC_free(p) +# define GC_REGISTER_FINALIZER(p, f, d, of, od) \ + GC_register_finalizer(p, f, d, of, od) +# define GC_REGISTER_FINALIZER_IGNORE_SELF(p, f, d, of, od) \ + GC_register_finalizer_ignore_self(p, f, d, of, od) +# define GC_MALLOC_STUBBORN(sz) GC_malloc_stubborn(sz) +# define GC_CHANGE_STUBBORN(p) GC_change_stubborn(p) +# define GC_END_STUBBORN_CHANGE(p) GC_end_stubborn_change(p) +# define GC_GENERAL_REGISTER_DISAPPEARING_LINK(link, obj) \ + GC_general_register_disappearing_link(link, obj) +# define GC_REGISTER_DISPLACEMENT(n) GC_register_displacement(n) +# endif +/* The following are included because they are often convenient, and */ +/* reduce the chance for a misspecifed size argument. But calls may */ +/* expand to something syntactically incorrect if t is a complicated */ +/* type expression. */ +# define GC_NEW(t) (t *)GC_MALLOC(sizeof (t)) +# define GC_NEW_ATOMIC(t) (t *)GC_MALLOC_ATOMIC(sizeof (t)) +# define GC_NEW_STUBBORN(t) (t *)GC_MALLOC_STUBBORN(sizeof (t)) +# define GC_NEW_UNCOLLECTABLE(t) (t *)GC_MALLOC_UNCOLLECTABLE(sizeof (t)) + +/* Finalization. Some of these primitives are grossly unsafe. */ +/* The idea is to make them both cheap, and sufficient to build */ +/* a safer layer, closer to PCedar finalization. */ +/* The interface represents my conclusions from a long discussion */ +/* with Alan Demers, Dan Greene, Carl Hauser, Barry Hayes, */ +/* Christian Jacobi, and Russ Atkinson. It's not perfect, and */ +/* probably nobody else agrees with it. Hans-J. Boehm 3/13/92 */ +typedef void (*GC_finalization_proc) + GC_PROTO((GC_PTR obj, GC_PTR client_data)); + +GC_API void GC_register_finalizer + GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd, + GC_finalization_proc *ofn, GC_PTR *ocd)); +GC_API void GC_debug_register_finalizer + GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd, + GC_finalization_proc *ofn, GC_PTR *ocd)); + /* When obj is no longer accessible, invoke */ + /* (*fn)(obj, cd). If a and b are inaccessible, and */ + /* a points to b (after disappearing links have been */ + /* made to disappear), then only a will be */ + /* finalized. (If this does not create any new */ + /* pointers to b, then b will be finalized after the */ + /* next collection.) Any finalizable object that */ + /* is reachable from itself by following one or more */ + /* pointers will not be finalized (or collected). */ + /* Thus cycles involving finalizable objects should */ + /* be avoided, or broken by disappearing links. */ + /* All but the last finalizer registered for an object */ + /* is ignored. */ + /* Finalization may be removed by passing 0 as fn. */ + /* Finalizers are implicitly unregistered just before */ + /* they are invoked. */ + /* The old finalizer and client data are stored in */ + /* *ofn and *ocd. */ + /* Fn is never invoked on an accessible object, */ + /* provided hidden pointers are converted to real */ + /* pointers only if the allocation lock is held, and */ + /* such conversions are not performed by finalization */ + /* routines. */ + /* If GC_register_finalizer is aborted as a result of */ + /* a signal, the object may be left with no */ + /* finalization, even if neither the old nor new */ + /* finalizer were NULL. */ + /* Obj should be the nonNULL starting address of an */ + /* object allocated by GC_malloc or friends. */ + /* Note that any garbage collectable object referenced */ + /* by cd will be considered accessible until the */ + /* finalizer is invoked. */ + +/* Another versions of the above follow. It ignores */ +/* self-cycles, i.e. pointers from a finalizable object to */ +/* itself. There is a stylistic argument that this is wrong, */ +/* but it's unavoidable for C++, since the compiler may */ +/* silently introduce these. It's also benign in that specific */ +/* case. */ +GC_API void GC_register_finalizer_ignore_self + GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd, + GC_finalization_proc *ofn, GC_PTR *ocd)); +GC_API void GC_debug_register_finalizer_ignore_self + GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd, + GC_finalization_proc *ofn, GC_PTR *ocd)); + +/* The following routine may be used to break cycles between */ +/* finalizable objects, thus causing cyclic finalizable */ +/* objects to be finalized in the correct order. Standard */ +/* use involves calling GC_register_disappearing_link(&p), */ +/* where p is a pointer that is not followed by finalization */ +/* code, and should not be considered in determining */ +/* finalization order. */ +GC_API int GC_register_disappearing_link GC_PROTO((GC_PTR * /* link */)); + /* Link should point to a field of a heap allocated */ + /* object obj. *link will be cleared when obj is */ + /* found to be inaccessible. This happens BEFORE any */ + /* finalization code is invoked, and BEFORE any */ + /* decisions about finalization order are made. */ + /* This is useful in telling the finalizer that */ + /* some pointers are not essential for proper */ + /* finalization. This may avoid finalization cycles. */ + /* Note that obj may be resurrected by another */ + /* finalizer, and thus the clearing of *link may */ + /* be visible to non-finalization code. */ + /* There's an argument that an arbitrary action should */ + /* be allowed here, instead of just clearing a pointer. */ + /* But this causes problems if that action alters, or */ + /* examines connectivity. */ + /* Returns 1 if link was already registered, 0 */ + /* otherwise. */ + /* Only exists for backward compatibility. See below: */ + +GC_API int GC_general_register_disappearing_link + GC_PROTO((GC_PTR * /* link */, GC_PTR obj)); + /* A slight generalization of the above. *link is */ + /* cleared when obj first becomes inaccessible. This */ + /* can be used to implement weak pointers easily and */ + /* safely. Typically link will point to a location */ + /* holding a disguised pointer to obj. (A pointer */ + /* inside an "atomic" object is effectively */ + /* disguised.) In this way soft */ + /* pointers are broken before any object */ + /* reachable from them are finalized. Each link */ + /* May be registered only once, i.e. with one obj */ + /* value. This was added after a long email discussion */ + /* with John Ellis. */ + /* Obj must be a pointer to the first word of an object */ + /* we allocated. It is unsafe to explicitly deallocate */ + /* the object containing link. Explicitly deallocating */ + /* obj may or may not cause link to eventually be */ + /* cleared. */ +GC_API int GC_unregister_disappearing_link GC_PROTO((GC_PTR * /* link */)); + /* Returns 0 if link was not actually registered. */ + /* Undoes a registration by either of the above two */ + /* routines. */ + +/* Auxiliary fns to make finalization work correctly with displaced */ +/* pointers introduced by the debugging allocators. */ +GC_API GC_PTR GC_make_closure GC_PROTO((GC_finalization_proc fn, GC_PTR data)); +GC_API void GC_debug_invoke_finalizer GC_PROTO((GC_PTR obj, GC_PTR data)); + +GC_API int GC_invoke_finalizers GC_PROTO((void)); + /* Run finalizers for all objects that are ready to */ + /* be finalized. Return the number of finalizers */ + /* that were run. Normally this is also called */ + /* implicitly during some allocations. If */ + /* GC-finalize_on_demand is nonzero, it must be called */ + /* explicitly. */ + +/* GC_set_warn_proc can be used to redirect or filter warning messages. */ +/* p may not be a NULL pointer. */ +typedef void (*GC_warn_proc) GC_PROTO((char *msg, GC_word arg)); +GC_API GC_warn_proc GC_set_warn_proc GC_PROTO((GC_warn_proc p)); + /* Returns old warning procedure. */ + +/* The following is intended to be used by a higher level */ +/* (e.g. cedar-like) finalization facility. It is expected */ +/* that finalization code will arrange for hidden pointers to */ +/* disappear. Otherwise objects can be accessed after they */ +/* have been collected. */ +/* Note that putting pointers in atomic objects or in */ +/* nonpointer slots of "typed" objects is equivalent to */ +/* disguising them in this way, and may have other advantages. */ +# if defined(I_HIDE_POINTERS) || defined(GC_I_HIDE_POINTERS) + typedef GC_word GC_hidden_pointer; +# define HIDE_POINTER(p) (~(GC_hidden_pointer)(p)) +# define REVEAL_POINTER(p) ((GC_PTR)(HIDE_POINTER(p))) + /* Converting a hidden pointer to a real pointer requires verifying */ + /* that the object still exists. This involves acquiring the */ + /* allocator lock to avoid a race with the collector. */ +# endif /* I_HIDE_POINTERS */ + +typedef GC_PTR (*GC_fn_type) GC_PROTO((GC_PTR client_data)); +GC_API GC_PTR GC_call_with_alloc_lock + GC_PROTO((GC_fn_type fn, GC_PTR client_data)); + +/* Check that p and q point to the same object. */ +/* Fail conspicuously if they don't. */ +/* Returns the first argument. */ +/* Succeeds if neither p nor q points to the heap. */ +/* May succeed if both p and q point to between heap objects. */ +GC_API GC_PTR GC_same_obj GC_PROTO((GC_PTR p, GC_PTR q)); + +/* Checked pointer pre- and post- increment operations. Note that */ +/* the second argument is in units of bytes, not multiples of the */ +/* object size. This should either be invoked from a macro, or the */ +/* call should be automatically generated. */ +GC_API GC_PTR GC_pre_incr GC_PROTO((GC_PTR *p, size_t how_much)); +GC_API GC_PTR GC_post_incr GC_PROTO((GC_PTR *p, size_t how_much)); + +/* Check that p is visible */ +/* to the collector as a possibly pointer containing location. */ +/* If it isn't fail conspicuously. */ +/* Returns the argument in all cases. May erroneously succeed */ +/* in hard cases. (This is intended for debugging use with */ +/* untyped allocations. The idea is that it should be possible, though */ +/* slow, to add such a call to all indirect pointer stores.) */ +/* Currently useless for multithreaded worlds. */ +GC_API GC_PTR GC_is_visible GC_PROTO((GC_PTR p)); + +/* Check that if p is a pointer to a heap page, then it points to */ +/* a valid displacement within a heap object. */ +/* Fail conspicuously if this property does not hold. */ +/* Uninteresting with ALL_INTERIOR_POINTERS. */ +/* Always returns its argument. */ +GC_API GC_PTR GC_is_valid_displacement GC_PROTO((GC_PTR p)); + +/* Safer, but slow, pointer addition. Probably useful mainly with */ +/* a preprocessor. Useful only for heap pointers. */ +#ifdef GC_DEBUG +# define GC_PTR_ADD3(x, n, type_of_result) \ + ((type_of_result)GC_same_obj((x)+(n), (x))) +# define GC_PRE_INCR3(x, n, type_of_result) \ + ((type_of_result)GC_pre_incr(&(x), (n)*sizeof(*x)) +# define GC_POST_INCR2(x, type_of_result) \ + ((type_of_result)GC_post_incr(&(x), sizeof(*x)) +# ifdef __GNUC__ +# define GC_PTR_ADD(x, n) \ + GC_PTR_ADD3(x, n, typeof(x)) +# define GC_PRE_INCR(x, n) \ + GC_PRE_INCR3(x, n, typeof(x)) +# define GC_POST_INCR(x, n) \ + GC_POST_INCR3(x, typeof(x)) +# else + /* We can't do this right without typeof, which ANSI */ + /* decided was not sufficiently useful. Repeatedly */ + /* mentioning the arguments seems too dangerous to be */ + /* useful. So does not casting the result. */ +# define GC_PTR_ADD(x, n) ((x)+(n)) +# endif +#else /* !GC_DEBUG */ +# define GC_PTR_ADD3(x, n, type_of_result) ((x)+(n)) +# define GC_PTR_ADD(x, n) ((x)+(n)) +# define GC_PRE_INCR3(x, n, type_of_result) ((x) += (n)) +# define GC_PRE_INCR(x, n) ((x) += (n)) +# define GC_POST_INCR2(x, n, type_of_result) ((x)++) +# define GC_POST_INCR(x, n) ((x)++) +#endif + +/* Safer assignment of a pointer to a nonstack location. */ +#ifdef GC_DEBUG +# ifdef __STDC__ +# define GC_PTR_STORE(p, q) \ + (*(void **)GC_is_visible(p) = GC_is_valid_displacement(q)) +# else +# define GC_PTR_STORE(p, q) \ + (*(char **)GC_is_visible(p) = GC_is_valid_displacement(q)) +# endif +#else /* !GC_DEBUG */ +# define GC_PTR_STORE(p, q) *((p) = (q)) +#endif + +/* Fynctions called to report pointer checking errors */ +GC_API void (*GC_same_obj_print_proc) GC_PROTO((GC_PTR p, GC_PTR q)); + +GC_API void (*GC_is_valid_displacement_print_proc) + GC_PROTO((GC_PTR p)); + +GC_API void (*GC_is_visible_print_proc) + GC_PROTO((GC_PTR p)); + +#if defined(_SOLARIS_PTHREADS) && !defined(SOLARIS_THREADS) +# define SOLARIS_THREADS +#endif + +#ifdef SOLARIS_THREADS +/* We need to intercept calls to many of the threads primitives, so */ +/* that we can locate thread stacks and stop the world. */ +/* Note also that the collector cannot see thread specific data. */ +/* Thread specific data should generally consist of pointers to */ +/* uncollectable objects, which are deallocated using the destructor */ +/* facility in thr_keycreate. */ +# include <thread.h> +# include <signal.h> + int GC_thr_create(void *stack_base, size_t stack_size, + void *(*start_routine)(void *), void *arg, long flags, + thread_t *new_thread); + int GC_thr_join(thread_t wait_for, thread_t *departed, void **status); + int GC_thr_suspend(thread_t target_thread); + int GC_thr_continue(thread_t target_thread); + void * GC_dlopen(const char *path, int mode); + +# ifdef _SOLARIS_PTHREADS +# include <pthread.h> + extern int GC_pthread_create(pthread_t *new_thread, + const pthread_attr_t *attr, + void * (*thread_execp)(void *), void *arg); + extern int GC_pthread_join(pthread_t wait_for, void **status); + +# undef thread_t + +# define pthread_join GC_pthread_join +# define pthread_create GC_pthread_create +#endif + +# define thr_create GC_thr_create +# define thr_join GC_thr_join +# define thr_suspend GC_thr_suspend +# define thr_continue GC_thr_continue +# define dlopen GC_dlopen + +# endif /* SOLARIS_THREADS */ + + +#if defined(IRIX_THREADS) || defined(LINUX_THREADS) +/* We treat these similarly. */ +# include <pthread.h> +# include <signal.h> + + int GC_pthread_create(pthread_t *new_thread, + const pthread_attr_t *attr, + void *(*start_routine)(void *), void *arg); + int GC_pthread_sigmask(int how, const sigset_t *set, sigset_t *oset); + int GC_pthread_join(pthread_t thread, void **retval); + +# define pthread_create GC_pthread_create +# define pthread_sigmask GC_pthread_sigmask +# define pthread_join GC_pthread_join + +#endif /* IRIX_THREADS || LINUX_THREADS */ + +# if defined(PCR) || defined(SOLARIS_THREADS) || defined(WIN32_THREADS) || \ + defined(IRIX_THREADS) || defined(LINUX_THREADS) || \ + defined(IRIX_JDK_THREADS) + /* Any flavor of threads except SRC_M3. */ +/* This returns a list of objects, linked through their first */ +/* word. Its use can greatly reduce lock contention problems, since */ +/* the allocation lock can be acquired and released many fewer times. */ +/* lb must be large enough to hold the pointer field. */ +GC_PTR GC_malloc_many(size_t lb); +#define GC_NEXT(p) (*(GC_PTR *)(p)) /* Retrieve the next element */ + /* in returned list. */ +extern void GC_thr_init(); /* Needed for Solaris/X86 */ + +#endif /* THREADS && !SRC_M3 */ + +/* + * If you are planning on putting + * the collector in a SunOS 5 dynamic library, you need to call GC_INIT() + * from the statically loaded program section. + * This circumvents a Solaris 2.X (X<=4) linker bug. + */ +#if defined(sparc) || defined(__sparc) +# define GC_INIT() { extern end, etext; \ + GC_noop(&end, &etext); } +#else +# if defined(__CYGWIN32__) && defined(GC_USE_DLL) + /* + * Similarly gnu-win32 DLLs need explicit initialization + */ +# define GC_INIT() { GC_add_roots(DATASTART, DATAEND); } +# else +# define GC_INIT() +# endif +#endif + +#if (defined(_MSDOS) || defined(_MSC_VER)) && (_M_IX86 >= 300) \ + || defined(_WIN32) + /* win32S may not free all resources on process exit. */ + /* This explicitly deallocates the heap. */ + GC_API void GC_win32_free_heap (); +#endif + +#ifdef __cplusplus + } /* end of extern "C" */ +#endif + +#endif /* _GC_H */ diff --git a/gc/include/gc_alloc.h b/gc/include/gc_alloc.h new file mode 100644 index 0000000..1f1d54a --- /dev/null +++ b/gc/include/gc_alloc.h @@ -0,0 +1,380 @@ +/* + * Copyright (c) 1996-1998 by Silicon Graphics. All rights reserved. + * + * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED + * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + * + * Permission is hereby granted to use or copy this program + * for any purpose, provided the above notices are retained on all copies. + * Permission to modify the code and to distribute modified code is granted, + * provided the above notices are retained, and a notice that the code was + * modified is included with the above copyright notice. + */ + +// +// This is a C++ header file that is intended to replace the SGI STL +// alloc.h. This assumes SGI STL version < 3.0. +// +// This assumes the collector has been compiled with -DATOMIC_UNCOLLECTABLE +// and -DALL_INTERIOR_POINTERS. We also recommend +// -DREDIRECT_MALLOC=GC_uncollectable_malloc. +// +// Some of this could be faster in the explicit deallocation case. In particular, +// we spend too much time clearing objects on the free lists. That could be avoided. +// +// This uses template classes with static members, and hence does not work +// with g++ 2.7.2 and earlier. +// + +#include "gc.h" + +#ifndef GC_ALLOC_H + +#define GC_ALLOC_H +#define __ALLOC_H // Prevent inclusion of the default version. Ugly. +#define __SGI_STL_ALLOC_H +#define __SGI_STL_INTERNAL_ALLOC_H + +#ifndef __ALLOC +# define __ALLOC alloc +#endif + +#include <stddef.h> +#include <string.h> + +// The following is just replicated from the conventional SGI alloc.h: + +template<class T, class alloc> +class simple_alloc { + +public: + static T *allocate(size_t n) + { return 0 == n? 0 : (T*) alloc::allocate(n * sizeof (T)); } + static T *allocate(void) + { return (T*) alloc::allocate(sizeof (T)); } + static void deallocate(T *p, size_t n) + { if (0 != n) alloc::deallocate(p, n * sizeof (T)); } + static void deallocate(T *p) + { alloc::deallocate(p, sizeof (T)); } +}; + +#include "gc.h" + +// The following need to match collector data structures. +// We can't include gc_priv.h, since that pulls in way too much stuff. +// This should eventually be factored out into another include file. + +extern "C" { + extern void ** const GC_objfreelist_ptr; + extern void ** const GC_aobjfreelist_ptr; + extern void ** const GC_uobjfreelist_ptr; + extern void ** const GC_auobjfreelist_ptr; + + extern void GC_incr_words_allocd(size_t words); + extern void GC_incr_mem_freed(size_t words); + + extern char * GC_generic_malloc_words_small(size_t word, int kind); +} + +// Object kinds; must match PTRFREE, NORMAL, UNCOLLECTABLE, and +// AUNCOLLECTABLE in gc_priv.h. + +enum { GC_PTRFREE = 0, GC_NORMAL = 1, GC_UNCOLLECTABLE = 2, + GC_AUNCOLLECTABLE = 3 }; + +enum { GC_max_fast_bytes = 255 }; + +enum { GC_bytes_per_word = sizeof(char *) }; + +enum { GC_byte_alignment = 8 }; + +enum { GC_word_alignment = GC_byte_alignment/GC_bytes_per_word }; + +inline void * &GC_obj_link(void * p) +{ return *(void **)p; } + +// Compute a number of words >= n+1 bytes. +// The +1 allows for pointers one past the end. +inline size_t GC_round_up(size_t n) +{ + return ((n + GC_byte_alignment)/GC_byte_alignment)*GC_word_alignment; +} + +// The same but don't allow for extra byte. +inline size_t GC_round_up_uncollectable(size_t n) +{ + return ((n + GC_byte_alignment - 1)/GC_byte_alignment)*GC_word_alignment; +} + +template <int dummy> +class GC_aux_template { +public: + // File local count of allocated words. Occasionally this is + // added into the global count. A separate count is necessary since the + // real one must be updated with a procedure call. + static size_t GC_words_recently_allocd; + + // Same for uncollectable mmory. Not yet reflected in either + // GC_words_recently_allocd or GC_non_gc_bytes. + static size_t GC_uncollectable_words_recently_allocd; + + // Similar counter for explicitly deallocated memory. + static size_t GC_mem_recently_freed; + + // Again for uncollectable memory. + static size_t GC_uncollectable_mem_recently_freed; + + static void * GC_out_of_line_malloc(size_t nwords, int kind); +}; + +template <int dummy> +size_t GC_aux_template<dummy>::GC_words_recently_allocd = 0; + +template <int dummy> +size_t GC_aux_template<dummy>::GC_uncollectable_words_recently_allocd = 0; + +template <int dummy> +size_t GC_aux_template<dummy>::GC_mem_recently_freed = 0; + +template <int dummy> +size_t GC_aux_template<dummy>::GC_uncollectable_mem_recently_freed = 0; + +template <int dummy> +void * GC_aux_template<dummy>::GC_out_of_line_malloc(size_t nwords, int kind) +{ + GC_words_recently_allocd += GC_uncollectable_words_recently_allocd; + GC_non_gc_bytes += + GC_bytes_per_word * GC_uncollectable_words_recently_allocd; + GC_uncollectable_words_recently_allocd = 0; + + GC_mem_recently_freed += GC_uncollectable_mem_recently_freed; + GC_non_gc_bytes -= + GC_bytes_per_word * GC_uncollectable_mem_recently_freed; + GC_uncollectable_mem_recently_freed = 0; + + GC_incr_words_allocd(GC_words_recently_allocd); + GC_words_recently_allocd = 0; + + GC_incr_mem_freed(GC_mem_recently_freed); + GC_mem_recently_freed = 0; + + return GC_generic_malloc_words_small(nwords, kind); +} + +typedef GC_aux_template<0> GC_aux; + +// A fast, single-threaded, garbage-collected allocator +// We assume the first word will be immediately overwritten. +// In this version, deallocation is not a noop, and explicit +// deallocation is likely to help performance. +template <int dummy> +class single_client_gc_alloc_template { + public: + static void * allocate(size_t n) + { + size_t nwords = GC_round_up(n); + void ** flh; + void * op; + + if (n > GC_max_fast_bytes) return GC_malloc(n); + flh = GC_objfreelist_ptr + nwords; + if (0 == (op = *flh)) { + return GC_aux::GC_out_of_line_malloc(nwords, GC_NORMAL); + } + *flh = GC_obj_link(op); + GC_aux::GC_words_recently_allocd += nwords; + return op; + } + static void * ptr_free_allocate(size_t n) + { + size_t nwords = GC_round_up(n); + void ** flh; + void * op; + + if (n > GC_max_fast_bytes) return GC_malloc_atomic(n); + flh = GC_aobjfreelist_ptr + nwords; + if (0 == (op = *flh)) { + return GC_aux::GC_out_of_line_malloc(nwords, GC_PTRFREE); + } + *flh = GC_obj_link(op); + GC_aux::GC_words_recently_allocd += nwords; + return op; + } + static void deallocate(void *p, size_t n) + { + size_t nwords = GC_round_up(n); + void ** flh; + + if (n > GC_max_fast_bytes) { + GC_free(p); + } else { + flh = GC_objfreelist_ptr + nwords; + GC_obj_link(p) = *flh; + memset((char *)p + GC_bytes_per_word, 0, + GC_bytes_per_word * (nwords - 1)); + *flh = p; + GC_aux::GC_mem_recently_freed += nwords; + } + } + static void ptr_free_deallocate(void *p, size_t n) + { + size_t nwords = GC_round_up(n); + void ** flh; + + if (n > GC_max_fast_bytes) { + GC_free(p); + } else { + flh = GC_aobjfreelist_ptr + nwords; + GC_obj_link(p) = *flh; + *flh = p; + GC_aux::GC_mem_recently_freed += nwords; + } + } +}; + +typedef single_client_gc_alloc_template<0> single_client_gc_alloc; + +// Once more, for uncollectable objects. +template <int dummy> +class single_client_alloc_template { + public: + static void * allocate(size_t n) + { + size_t nwords = GC_round_up_uncollectable(n); + void ** flh; + void * op; + + if (n > GC_max_fast_bytes) return GC_malloc_uncollectable(n); + flh = GC_uobjfreelist_ptr + nwords; + if (0 == (op = *flh)) { + return GC_aux::GC_out_of_line_malloc(nwords, GC_UNCOLLECTABLE); + } + *flh = GC_obj_link(op); + GC_aux::GC_uncollectable_words_recently_allocd += nwords; + return op; + } + static void * ptr_free_allocate(size_t n) + { + size_t nwords = GC_round_up_uncollectable(n); + void ** flh; + void * op; + + if (n > GC_max_fast_bytes) return GC_malloc_atomic_uncollectable(n); + flh = GC_auobjfreelist_ptr + nwords; + if (0 == (op = *flh)) { + return GC_aux::GC_out_of_line_malloc(nwords, GC_AUNCOLLECTABLE); + } + *flh = GC_obj_link(op); + GC_aux::GC_uncollectable_words_recently_allocd += nwords; + return op; + } + static void deallocate(void *p, size_t n) + { + size_t nwords = GC_round_up_uncollectable(n); + void ** flh; + + if (n > GC_max_fast_bytes) { + GC_free(p); + } else { + flh = GC_uobjfreelist_ptr + nwords; + GC_obj_link(p) = *flh; + *flh = p; + GC_aux::GC_uncollectable_mem_recently_freed += nwords; + } + } + static void ptr_free_deallocate(void *p, size_t n) + { + size_t nwords = GC_round_up_uncollectable(n); + void ** flh; + + if (n > GC_max_fast_bytes) { + GC_free(p); + } else { + flh = GC_auobjfreelist_ptr + nwords; + GC_obj_link(p) = *flh; + *flh = p; + GC_aux::GC_uncollectable_mem_recently_freed += nwords; + } + } +}; + +typedef single_client_alloc_template<0> single_client_alloc; + +template < int dummy > +class gc_alloc_template { + public: + static void * allocate(size_t n) { return GC_malloc(n); } + static void * ptr_free_allocate(size_t n) + { return GC_malloc_atomic(n); } + static void deallocate(void *, size_t) { } + static void ptr_free_deallocate(void *, size_t) { } +}; + +typedef gc_alloc_template < 0 > gc_alloc; + +template < int dummy > +class alloc_template { + public: + static void * allocate(size_t n) { return GC_malloc_uncollectable(n); } + static void * ptr_free_allocate(size_t n) + { return GC_malloc_atomic_uncollectable(n); } + static void deallocate(void *p, size_t) { GC_free(p); } + static void ptr_free_deallocate(void *p, size_t) { GC_free(p); } +}; + +typedef alloc_template < 0 > alloc; + +#ifdef _SGI_SOURCE + +// We want to specialize simple_alloc so that it does the right thing +// for all pointerfree types. At the moment there is no portable way to +// even approximate that. The following approximation should work for +// SGI compilers, and perhaps some others. + +# define __GC_SPECIALIZE(T,alloc) \ +class simple_alloc<T, alloc> { \ +public: \ + static T *allocate(size_t n) \ + { return 0 == n? 0 : \ + (T*) alloc::ptr_free_allocate(n * sizeof (T)); } \ + static T *allocate(void) \ + { return (T*) alloc::ptr_free_allocate(sizeof (T)); } \ + static void deallocate(T *p, size_t n) \ + { if (0 != n) alloc::ptr_free_deallocate(p, n * sizeof (T)); } \ + static void deallocate(T *p) \ + { alloc::ptr_free_deallocate(p, sizeof (T)); } \ +}; + +__GC_SPECIALIZE(char, gc_alloc) +__GC_SPECIALIZE(int, gc_alloc) +__GC_SPECIALIZE(unsigned, gc_alloc) +__GC_SPECIALIZE(float, gc_alloc) +__GC_SPECIALIZE(double, gc_alloc) + +__GC_SPECIALIZE(char, alloc) +__GC_SPECIALIZE(int, alloc) +__GC_SPECIALIZE(unsigned, alloc) +__GC_SPECIALIZE(float, alloc) +__GC_SPECIALIZE(double, alloc) + +__GC_SPECIALIZE(char, single_client_gc_alloc) +__GC_SPECIALIZE(int, single_client_gc_alloc) +__GC_SPECIALIZE(unsigned, single_client_gc_alloc) +__GC_SPECIALIZE(float, single_client_gc_alloc) +__GC_SPECIALIZE(double, single_client_gc_alloc) + +__GC_SPECIALIZE(char, single_client_alloc) +__GC_SPECIALIZE(int, single_client_alloc) +__GC_SPECIALIZE(unsigned, single_client_alloc) +__GC_SPECIALIZE(float, single_client_alloc) +__GC_SPECIALIZE(double, single_client_alloc) + +#ifdef __STL_USE_STD_ALLOCATORS + +???copy stuff from stl_alloc.h or remove it to a different file ??? + +#endif /* __STL_USE_STD_ALLOCATORS */ + +#endif /* _SGI_SOURCE */ + +#endif /* GC_ALLOC_H */ diff --git a/gc/include/gc_cpp.h b/gc/include/gc_cpp.h new file mode 100644 index 0000000..ad7df5d --- /dev/null +++ b/gc/include/gc_cpp.h @@ -0,0 +1,290 @@ +#ifndef GC_CPP_H +#define GC_CPP_H +/**************************************************************************** +Copyright (c) 1994 by Xerox Corporation. All rights reserved. + +THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED +OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + +Permission is hereby granted to use or copy this program for any +purpose, provided the above notices are retained on all copies. +Permission to modify the code and to distribute modified code is +granted, provided the above notices are retained, and a notice that +the code was modified is included with the above copyright notice. +**************************************************************************** + +C++ Interface to the Boehm Collector + + John R. Ellis and Jesse Hull + Last modified on Mon Jul 24 15:43:42 PDT 1995 by ellis + +This interface provides access to the Boehm collector. It provides +basic facilities similar to those described in "Safe, Efficient +Garbage Collection for C++", by John R. Elis and David L. Detlefs +(ftp.parc.xerox.com:/pub/ellis/gc). + +All heap-allocated objects are either "collectable" or +"uncollectable". Programs must explicitly delete uncollectable +objects, whereas the garbage collector will automatically delete +collectable objects when it discovers them to be inaccessible. +Collectable objects may freely point at uncollectable objects and vice +versa. + +Objects allocated with the built-in "::operator new" are uncollectable. + +Objects derived from class "gc" are collectable. For example: + + class A: public gc {...}; + A* a = new A; // a is collectable. + +Collectable instances of non-class types can be allocated using the GC +placement: + + typedef int A[ 10 ]; + A* a = new (GC) A; + +Uncollectable instances of classes derived from "gc" can be allocated +using the NoGC placement: + + class A: public gc {...}; + A* a = new (NoGC) A; // a is uncollectable. + +Both uncollectable and collectable objects can be explicitly deleted +with "delete", which invokes an object's destructors and frees its +storage immediately. + +A collectable object may have a clean-up function, which will be +invoked when the collector discovers the object to be inaccessible. +An object derived from "gc_cleanup" or containing a member derived +from "gc_cleanup" has a default clean-up function that invokes the +object's destructors. Explicit clean-up functions may be specified as +an additional placement argument: + + A* a = ::new (GC, MyCleanup) A; + +An object is considered "accessible" by the collector if it can be +reached by a path of pointers from static variables, automatic +variables of active functions, or from some object with clean-up +enabled; pointers from an object to itself are ignored. + +Thus, if objects A and B both have clean-up functions, and A points at +B, B is considered accessible. After A's clean-up is invoked and its +storage released, B will then become inaccessible and will have its +clean-up invoked. If A points at B and B points to A, forming a +cycle, then that's considered a storage leak, and neither will be +collectable. See the interface gc.h for low-level facilities for +handling such cycles of objects with clean-up. + +The collector cannot guarrantee that it will find all inaccessible +objects. In practice, it finds almost all of them. + + +Cautions: + +1. Be sure the collector has been augmented with "make c++". + +2. If your compiler supports the new "operator new[]" syntax, then +add -DOPERATOR_NEW_ARRAY to the Makefile. + +If your compiler doesn't support "operator new[]", beware that an +array of type T, where T is derived from "gc", may or may not be +allocated as a collectable object (it depends on the compiler). Use +the explicit GC placement to make the array collectable. For example: + + class A: public gc {...}; + A* a1 = new A[ 10 ]; // collectable or uncollectable? + A* a2 = new (GC) A[ 10 ]; // collectable + +3. The destructors of collectable arrays of objects derived from +"gc_cleanup" will not be invoked properly. For example: + + class A: public gc_cleanup {...}; + A* a = new (GC) A[ 10 ]; // destructors not invoked correctly + +Typically, only the destructor for the first element of the array will +be invoked when the array is garbage-collected. To get all the +destructors of any array executed, you must supply an explicit +clean-up function: + + A* a = new (GC, MyCleanUp) A[ 10 ]; + +(Implementing clean-up of arrays correctly, portably, and in a way +that preserves the correct exception semantics requires a language +extension, e.g. the "gc" keyword.) + +4. Compiler bugs: + +* Solaris 2's CC (SC3.0) doesn't implement t->~T() correctly, so the +destructors of classes derived from gc_cleanup won't be invoked. +You'll have to explicitly register a clean-up function with +new-placement syntax. + +* Evidently cfront 3.0 does not allow destructors to be explicitly +invoked using the ANSI-conforming syntax t->~T(). If you're using +cfront 3.0, you'll have to comment out the class gc_cleanup, which +uses explicit invocation. + +****************************************************************************/ + +#include "gc.h" + +#ifndef THINK_CPLUS +#define _cdecl +#endif + +#if ! defined( OPERATOR_NEW_ARRAY ) \ + && (__BORLANDC__ >= 0x450 || (__GNUC__ >= 2 && __GNUC_MINOR__ >= 6) \ + || __WATCOMC__ >= 1050) +# define OPERATOR_NEW_ARRAY +#endif + +enum GCPlacement {GC, NoGC, PointerFreeGC}; + +class gc {public: + inline void* operator new( size_t size ); + inline void* operator new( size_t size, GCPlacement gcp ); + inline void operator delete( void* obj ); + +#ifdef OPERATOR_NEW_ARRAY + inline void* operator new[]( size_t size ); + inline void* operator new[]( size_t size, GCPlacement gcp ); + inline void operator delete[]( void* obj ); +#endif /* OPERATOR_NEW_ARRAY */ + }; + /* + Instances of classes derived from "gc" will be allocated in the + collected heap by default, unless an explicit NoGC placement is + specified. */ + +class gc_cleanup: virtual public gc {public: + inline gc_cleanup(); + inline virtual ~gc_cleanup(); +private: + inline static void _cdecl cleanup( void* obj, void* clientData );}; + /* + Instances of classes derived from "gc_cleanup" will be allocated + in the collected heap by default. When the collector discovers an + inaccessible object derived from "gc_cleanup" or containing a + member derived from "gc_cleanup", its destructors will be + invoked. */ + +extern "C" {typedef void (*GCCleanUpFunc)( void* obj, void* clientData );} + +inline void* operator new( + size_t size, + GCPlacement gcp, + GCCleanUpFunc cleanup = 0, + void* clientData = 0 ); + /* + Allocates a collectable or uncollected object, according to the + value of "gcp". + + For collectable objects, if "cleanup" is non-null, then when the + allocated object "obj" becomes inaccessible, the collector will + invoke the function "cleanup( obj, clientData )" but will not + invoke the object's destructors. It is an error to explicitly + delete an object allocated with a non-null "cleanup". + + It is an error to specify a non-null "cleanup" with NoGC or for + classes derived from "gc_cleanup" or containing members derived + from "gc_cleanup". */ + +#ifdef OPERATOR_NEW_ARRAY + +inline void* operator new[]( + size_t size, + GCPlacement gcp, + GCCleanUpFunc cleanup = 0, + void* clientData = 0 ); + /* + The operator new for arrays, identical to the above. */ + +#endif /* OPERATOR_NEW_ARRAY */ + +/**************************************************************************** + +Inline implementation + +****************************************************************************/ + +inline void* gc::operator new( size_t size ) { + return GC_MALLOC( size );} + +inline void* gc::operator new( size_t size, GCPlacement gcp ) { + if (gcp == GC) + return GC_MALLOC( size ); + else if (gcp == PointerFreeGC) + return GC_MALLOC_ATOMIC( size ); + else + return GC_MALLOC_UNCOLLECTABLE( size );} + +inline void gc::operator delete( void* obj ) { + GC_FREE( obj );} + + +#ifdef OPERATOR_NEW_ARRAY + +inline void* gc::operator new[]( size_t size ) { + return gc::operator new( size );} + +inline void* gc::operator new[]( size_t size, GCPlacement gcp ) { + return gc::operator new( size, gcp );} + +inline void gc::operator delete[]( void* obj ) { + gc::operator delete( obj );} + +#endif /* OPERATOR_NEW_ARRAY */ + + +inline gc_cleanup::~gc_cleanup() { + GC_REGISTER_FINALIZER_IGNORE_SELF( GC_base(this), 0, 0, 0, 0 );} + +inline void gc_cleanup::cleanup( void* obj, void* displ ) { + ((gc_cleanup*) ((char*) obj + (ptrdiff_t) displ))->~gc_cleanup();} + +inline gc_cleanup::gc_cleanup() { + GC_finalization_proc oldProc; + void* oldData; + void* base = GC_base( (void *) this ); + if (0 == base) return; + GC_REGISTER_FINALIZER_IGNORE_SELF( + base, cleanup, (void*) ((char*) this - (char*) base), + &oldProc, &oldData ); + if (0 != oldProc) { + GC_REGISTER_FINALIZER_IGNORE_SELF( base, oldProc, oldData, 0, 0 );}} + +inline void* operator new( + size_t size, + GCPlacement gcp, + GCCleanUpFunc cleanup, + void* clientData ) +{ + void* obj; + + if (gcp == GC) { + obj = GC_MALLOC( size ); + if (cleanup != 0) + GC_REGISTER_FINALIZER_IGNORE_SELF( + obj, cleanup, clientData, 0, 0 );} + else if (gcp == PointerFreeGC) { + obj = GC_MALLOC_ATOMIC( size );} + else { + obj = GC_MALLOC_UNCOLLECTABLE( size );}; + return obj;} + + +#ifdef OPERATOR_NEW_ARRAY + +inline void* operator new[]( + size_t size, + GCPlacement gcp, + GCCleanUpFunc cleanup, + void* clientData ) +{ + return ::operator new( size, gcp, cleanup, clientData );} + +#endif /* OPERATOR_NEW_ARRAY */ + + +#endif /* GC_CPP_H */ + diff --git a/gc/include/gc_inl.h b/gc/include/gc_inl.h new file mode 100644 index 0000000..700843b --- /dev/null +++ b/gc/include/gc_inl.h @@ -0,0 +1,103 @@ +/* + * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers + * Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved. + * + * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED + * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + * + * Permission is hereby granted to use or copy this program + * for any purpose, provided the above notices are retained on all copies. + * Permission to modify the code and to distribute modified code is granted, + * provided the above notices are retained, and a notice that the code was + * modified is included with the above copyright notice. + */ +/* Boehm, October 3, 1995 2:07 pm PDT */ + +# ifndef GC_PRIVATE_H +# include "private/gc_priv.h" +# endif + +/* USE OF THIS FILE IS NOT RECOMMENDED unless the collector has been */ +/* compiled without -DALL_INTERIOR_POINTERS or with */ +/* -DDONT_ADD_BYTE_AT_END, or the specified size includes a pointerfree */ +/* word at the end. In the standard collector configuration, */ +/* the final word of each object may not be scanned. */ +/* This is most useful for compilers that generate C. */ +/* Manual use is hereby discouraged. */ + +/* Allocate n words (NOT BYTES). X is made to point to the result. */ +/* It is assumed that n < MAXOBJSZ, and */ +/* that n > 0. On machines requiring double word alignment of some */ +/* data, we also assume that n is 1 or even. This bypasses the */ +/* MERGE_SIZES mechanism. In order to minimize the number of distinct */ +/* free lists that are maintained, the caller should ensure that a */ +/* small number of distinct values of n are used. (The MERGE_SIZES */ +/* mechanism normally does this by ensuring that only the leading three */ +/* bits of n may be nonzero. See misc.c for details.) We really */ +/* recommend this only in cases in which n is a constant, and no */ +/* locking is required. */ +/* In that case it may allow the compiler to perform substantial */ +/* additional optimizations. */ +# define GC_MALLOC_WORDS(result,n) \ +{ \ + register ptr_t op; \ + register ptr_t *opp; \ + DCL_LOCK_STATE; \ + \ + opp = &(GC_objfreelist[n]); \ + FASTLOCK(); \ + if( !FASTLOCK_SUCCEEDED() || (op = *opp) == 0 ) { \ + FASTUNLOCK(); \ + (result) = GC_generic_malloc_words_small((n), NORMAL); \ + } else { \ + *opp = obj_link(op); \ + obj_link(op) = 0; \ + GC_words_allocd += (n); \ + FASTUNLOCK(); \ + (result) = (GC_PTR) op; \ + } \ +} + + +/* The same for atomic objects: */ +# define GC_MALLOC_ATOMIC_WORDS(result,n) \ +{ \ + register ptr_t op; \ + register ptr_t *opp; \ + DCL_LOCK_STATE; \ + \ + opp = &(GC_aobjfreelist[n]); \ + FASTLOCK(); \ + if( !FASTLOCK_SUCCEEDED() || (op = *opp) == 0 ) { \ + FASTUNLOCK(); \ + (result) = GC_generic_malloc_words_small((n), PTRFREE); \ + } else { \ + *opp = obj_link(op); \ + obj_link(op) = 0; \ + GC_words_allocd += (n); \ + FASTUNLOCK(); \ + (result) = (GC_PTR) op; \ + } \ +} + +/* And once more for two word initialized objects: */ +# define GC_CONS(result, first, second) \ +{ \ + register ptr_t op; \ + register ptr_t *opp; \ + DCL_LOCK_STATE; \ + \ + opp = &(GC_objfreelist[2]); \ + FASTLOCK(); \ + if( !FASTLOCK_SUCCEEDED() || (op = *opp) == 0 ) { \ + FASTUNLOCK(); \ + op = GC_generic_malloc_words_small(2, NORMAL); \ + } else { \ + *opp = obj_link(op); \ + GC_words_allocd += 2; \ + FASTUNLOCK(); \ + } \ + ((word *)op)[0] = (word)(first); \ + ((word *)op)[1] = (word)(second); \ + (result) = (GC_PTR) op; \ +} diff --git a/gc/include/gc_inline.h b/gc/include/gc_inline.h new file mode 100644 index 0000000..db62d1d --- /dev/null +++ b/gc/include/gc_inline.h @@ -0,0 +1 @@ +# include "gc_inl.h" diff --git a/gc/include/gc_typed.h b/gc/include/gc_typed.h new file mode 100644 index 0000000..e4a6b94 --- /dev/null +++ b/gc/include/gc_typed.h @@ -0,0 +1,91 @@ +/* + * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers + * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved. + * Copyright 1996 Silicon Graphics. All rights reserved. + * + * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED + * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + * + * Permission is hereby granted to use or copy this program + * for any purpose, provided the above notices are retained on all copies. + * Permission to modify the code and to distribute modified code is granted, + * provided the above notices are retained, and a notice that the code was + * modified is included with the above copyright notice. + */ +/* + * Some simple primitives for allocation with explicit type information. + * Facilities for dynamic type inference may be added later. + * Should be used only for extremely performance critical applications, + * or if conservative collector leakage is otherwise a problem (unlikely). + * Note that this is implemented completely separately from the rest + * of the collector, and is not linked in unless referenced. + * This does not currently support GC_DEBUG in any interesting way. + */ +/* Boehm, May 19, 1994 2:13 pm PDT */ + +#ifndef _GC_TYPED_H +# define _GC_TYPED_H +# ifndef _GC_H +# include "gc.h" +# endif + +typedef GC_word * GC_bitmap; + /* The least significant bit of the first word is one if */ + /* the first word in the object may be a pointer. */ + +# define GC_get_bit(bm, index) \ + (((bm)[divWORDSZ(index)] >> modWORDSZ(index)) & 1) +# define GC_set_bit(bm, index) \ + (bm)[divWORDSZ(index)] |= (word)1 << modWORDSZ(index) + +typedef GC_word GC_descr; + +GC_API GC_descr GC_make_descriptor GC_PROTO((GC_bitmap bm, size_t len)); + /* Return a type descriptor for the object whose layout */ + /* is described by the argument. */ + /* The least significant bit of the first word is one */ + /* if the first word in the object may be a pointer. */ + /* The second argument specifies the number of */ + /* meaningful bits in the bitmap. The actual object */ + /* may be larger (but not smaller). Any additional */ + /* words in the object are assumed not to contain */ + /* pointers. */ + /* Returns a conservative approximation in the */ + /* (unlikely) case of insufficient memory to build */ + /* the descriptor. Calls to GC_make_descriptor */ + /* may consume some amount of a finite resource. This */ + /* is intended to be called once per type, not once */ + /* per allocation. */ + +GC_API GC_PTR GC_malloc_explicitly_typed + GC_PROTO((size_t size_in_bytes, GC_descr d)); + /* Allocate an object whose layout is described by d. */ + /* The resulting object MAY NOT BE PASSED TO REALLOC. */ + +GC_API GC_PTR GC_malloc_explicitly_typed_ignore_off_page + GC_PROTO((size_t size_in_bytes, GC_descr d)); + +GC_API GC_PTR GC_calloc_explicitly_typed + GC_PROTO((size_t nelements, + size_t element_size_in_bytes, + GC_descr d)); + /* Allocate an array of nelements elements, each of the */ + /* given size, and with the given descriptor. */ + /* The elemnt size must be a multiple of the byte */ + /* alignment required for pointers. E.g. on a 32-bit */ + /* machine with 16-bit aligned pointers, size_in_bytes */ + /* must be a multiple of 2. */ + +#ifdef GC_DEBUG +# define GC_MALLOC_EXPLICTLY_TYPED(bytes, d) GC_MALLOC(bytes) +# define GC_CALLOC_EXPLICTLY_TYPED(n, bytes, d) GC_MALLOC(n*bytes) +#else +# define GC_MALLOC_EXPLICTLY_TYPED(bytes, d) \ + GC_malloc_explicitly_typed(bytes, d) +# define GC_CALLOC_EXPLICTLY_TYPED(n, bytes, d) \ + GC_calloc_explicitly_typed(n, bytes, d) +#endif /* !GC_DEBUG */ + + +#endif /* _GC_TYPED_H */ + diff --git a/gc/include/javaxfc.h b/gc/include/javaxfc.h new file mode 100644 index 0000000..880020c --- /dev/null +++ b/gc/include/javaxfc.h @@ -0,0 +1,41 @@ +# ifndef GC_H +# include "gc.h" +# endif + +/* + * Invoke all remaining finalizers that haven't yet been run. + * This is needed for strict compliance with the Java standard, + * which can make the runtime guarantee that all finalizers are run. + * This is problematic for several reasons: + * 1) It means that finalizers, and all methods calle by them, + * must be prepared to deal with objects that have been finalized in + * spite of the fact that they are still referenced by statically + * allocated pointer variables. + * 1) It may mean that we get stuck in an infinite loop running + * finalizers which create new finalizable objects, though that's + * probably unlikely. + * Thus this is not recommended for general use. + */ +void GC_finalize_all(); + +/* + * A version of GC_register_finalizer that allows the object to be + * finalized before the objects it references. This is again error + * prone, in that it makes it easy to accidentally reference finalized + * objects. Again, recommended only for JVM implementors. + */ +void GC_register_finalizer_no_order(GC_PTR obj, + GC_finalization_proc fn, GC_PTR cd, + GC_finalization_proc *ofn, GC_PTR * ocd); + +void GC_debug_register_finalizer_no_order(GC_PTR obj, + GC_finalization_proc fn, GC_PTR cd, + GC_finalization_proc *ofn, GC_PTR * ocd); + +#ifdef GC_DEBUG +# define GC_REGISTER_FINALIZER(p, f, d, of, od) \ + GC_debug_register_finalizer_no_order(p, f, d, of, od) +#else +# define GC_REGISTER_FINALIZER(p, f, d, of, od) \ + GC_register_finalizer_no_order(p, f, d, of, od) +#endif diff --git a/gc/include/leak_detector.h b/gc/include/leak_detector.h new file mode 100644 index 0000000..6786825 --- /dev/null +++ b/gc/include/leak_detector.h @@ -0,0 +1,7 @@ +#define GC_DEBUG +#include "gc.h" +#define malloc(n) GC_MALLOC(n) +#define calloc(m,n) GC_MALLOC(m*n) +#define free(p) GC_FREE(p) +#define realloc(p,n) GC_REALLOC(n) +#define CHECK_LEAKS() GC_gcollect() diff --git a/gc/include/new_gc_alloc.h b/gc/include/new_gc_alloc.h new file mode 100644 index 0000000..5771388 --- /dev/null +++ b/gc/include/new_gc_alloc.h @@ -0,0 +1,456 @@ +/* + * Copyright (c) 1996-1998 by Silicon Graphics. All rights reserved. + * + * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED + * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + * + * Permission is hereby granted to use or copy this program + * for any purpose, provided the above notices are retained on all copies. + * Permission to modify the code and to distribute modified code is granted, + * provided the above notices are retained, and a notice that the code was + * modified is included with the above copyright notice. + */ + +// +// This is a revision of gc_alloc.h for SGI STL versions > 3.0 +// Unlike earlier versions, it supplements the standard "alloc.h" +// instead of replacing it. +// +// This is sloppy about variable names used in header files. +// It also doesn't yet understand the new header file names or +// namespaces. +// +// This assumes the collector has been compiled with -DATOMIC_UNCOLLECTABLE +// and -DALL_INTERIOR_POINTERS. We also recommend +// -DREDIRECT_MALLOC=GC_uncollectable_malloc. +// +// Some of this could be faster in the explicit deallocation case. +// In particular, we spend too much time clearing objects on the +// free lists. That could be avoided. +// +// This uses template classes with static members, and hence does not work +// with g++ 2.7.2 and earlier. +// +// Unlike its predecessor, this one simply defines +// gc_alloc +// single_client_gc_alloc +// traceable_alloc +// single_client_traceable_alloc +// +// It does not redefine alloc. Nor does it change the default allocator, +// though the user may wish to do so. (The argument against changing +// the default allocator is that it may introduce subtle link compatibility +// problems. The argument for changing it is that the usual default +// allocator is usually a very bad choice for a garbage collected environment.) +// + +#ifndef GC_ALLOC_H + +#include "gc.h" +#include <alloc.h> + +#define GC_ALLOC_H + +#include <stddef.h> +#include <string.h> + +// The following need to match collector data structures. +// We can't include gc_priv.h, since that pulls in way too much stuff. +// This should eventually be factored out into another include file. + +extern "C" { + extern void ** const GC_objfreelist_ptr; + extern void ** const GC_aobjfreelist_ptr; + extern void ** const GC_uobjfreelist_ptr; + extern void ** const GC_auobjfreelist_ptr; + + extern void GC_incr_words_allocd(size_t words); + extern void GC_incr_mem_freed(size_t words); + + extern char * GC_generic_malloc_words_small(size_t word, int kind); +} + +// Object kinds; must match PTRFREE, NORMAL, UNCOLLECTABLE, and +// AUNCOLLECTABLE in gc_priv.h. + +enum { GC_PTRFREE = 0, GC_NORMAL = 1, GC_UNCOLLECTABLE = 2, + GC_AUNCOLLECTABLE = 3 }; + +enum { GC_max_fast_bytes = 255 }; + +enum { GC_bytes_per_word = sizeof(char *) }; + +enum { GC_byte_alignment = 8 }; + +enum { GC_word_alignment = GC_byte_alignment/GC_bytes_per_word }; + +inline void * &GC_obj_link(void * p) +{ return *(void **)p; } + +// Compute a number of words >= n+1 bytes. +// The +1 allows for pointers one past the end. +inline size_t GC_round_up(size_t n) +{ + return ((n + GC_byte_alignment)/GC_byte_alignment)*GC_word_alignment; +} + +// The same but don't allow for extra byte. +inline size_t GC_round_up_uncollectable(size_t n) +{ + return ((n + GC_byte_alignment - 1)/GC_byte_alignment)*GC_word_alignment; +} + +template <int dummy> +class GC_aux_template { +public: + // File local count of allocated words. Occasionally this is + // added into the global count. A separate count is necessary since the + // real one must be updated with a procedure call. + static size_t GC_words_recently_allocd; + + // Same for uncollectable mmory. Not yet reflected in either + // GC_words_recently_allocd or GC_non_gc_bytes. + static size_t GC_uncollectable_words_recently_allocd; + + // Similar counter for explicitly deallocated memory. + static size_t GC_mem_recently_freed; + + // Again for uncollectable memory. + static size_t GC_uncollectable_mem_recently_freed; + + static void * GC_out_of_line_malloc(size_t nwords, int kind); +}; + +template <int dummy> +size_t GC_aux_template<dummy>::GC_words_recently_allocd = 0; + +template <int dummy> +size_t GC_aux_template<dummy>::GC_uncollectable_words_recently_allocd = 0; + +template <int dummy> +size_t GC_aux_template<dummy>::GC_mem_recently_freed = 0; + +template <int dummy> +size_t GC_aux_template<dummy>::GC_uncollectable_mem_recently_freed = 0; + +template <int dummy> +void * GC_aux_template<dummy>::GC_out_of_line_malloc(size_t nwords, int kind) +{ + GC_words_recently_allocd += GC_uncollectable_words_recently_allocd; + GC_non_gc_bytes += + GC_bytes_per_word * GC_uncollectable_words_recently_allocd; + GC_uncollectable_words_recently_allocd = 0; + + GC_mem_recently_freed += GC_uncollectable_mem_recently_freed; + GC_non_gc_bytes -= + GC_bytes_per_word * GC_uncollectable_mem_recently_freed; + GC_uncollectable_mem_recently_freed = 0; + + GC_incr_words_allocd(GC_words_recently_allocd); + GC_words_recently_allocd = 0; + + GC_incr_mem_freed(GC_mem_recently_freed); + GC_mem_recently_freed = 0; + + return GC_generic_malloc_words_small(nwords, kind); +} + +typedef GC_aux_template<0> GC_aux; + +// A fast, single-threaded, garbage-collected allocator +// We assume the first word will be immediately overwritten. +// In this version, deallocation is not a noop, and explicit +// deallocation is likely to help performance. +template <int dummy> +class single_client_gc_alloc_template { + public: + static void * allocate(size_t n) + { + size_t nwords = GC_round_up(n); + void ** flh; + void * op; + + if (n > GC_max_fast_bytes) return GC_malloc(n); + flh = GC_objfreelist_ptr + nwords; + if (0 == (op = *flh)) { + return GC_aux::GC_out_of_line_malloc(nwords, GC_NORMAL); + } + *flh = GC_obj_link(op); + GC_aux::GC_words_recently_allocd += nwords; + return op; + } + static void * ptr_free_allocate(size_t n) + { + size_t nwords = GC_round_up(n); + void ** flh; + void * op; + + if (n > GC_max_fast_bytes) return GC_malloc_atomic(n); + flh = GC_aobjfreelist_ptr + nwords; + if (0 == (op = *flh)) { + return GC_aux::GC_out_of_line_malloc(nwords, GC_PTRFREE); + } + *flh = GC_obj_link(op); + GC_aux::GC_words_recently_allocd += nwords; + return op; + } + static void deallocate(void *p, size_t n) + { + size_t nwords = GC_round_up(n); + void ** flh; + + if (n > GC_max_fast_bytes) { + GC_free(p); + } else { + flh = GC_objfreelist_ptr + nwords; + GC_obj_link(p) = *flh; + memset((char *)p + GC_bytes_per_word, 0, + GC_bytes_per_word * (nwords - 1)); + *flh = p; + GC_aux::GC_mem_recently_freed += nwords; + } + } + static void ptr_free_deallocate(void *p, size_t n) + { + size_t nwords = GC_round_up(n); + void ** flh; + + if (n > GC_max_fast_bytes) { + GC_free(p); + } else { + flh = GC_aobjfreelist_ptr + nwords; + GC_obj_link(p) = *flh; + *flh = p; + GC_aux::GC_mem_recently_freed += nwords; + } + } +}; + +typedef single_client_gc_alloc_template<0> single_client_gc_alloc; + +// Once more, for uncollectable objects. +template <int dummy> +class single_client_traceable_alloc_template { + public: + static void * allocate(size_t n) + { + size_t nwords = GC_round_up_uncollectable(n); + void ** flh; + void * op; + + if (n > GC_max_fast_bytes) return GC_malloc_uncollectable(n); + flh = GC_uobjfreelist_ptr + nwords; + if (0 == (op = *flh)) { + return GC_aux::GC_out_of_line_malloc(nwords, GC_UNCOLLECTABLE); + } + *flh = GC_obj_link(op); + GC_aux::GC_uncollectable_words_recently_allocd += nwords; + return op; + } + static void * ptr_free_allocate(size_t n) + { + size_t nwords = GC_round_up_uncollectable(n); + void ** flh; + void * op; + + if (n > GC_max_fast_bytes) return GC_malloc_atomic_uncollectable(n); + flh = GC_auobjfreelist_ptr + nwords; + if (0 == (op = *flh)) { + return GC_aux::GC_out_of_line_malloc(nwords, GC_AUNCOLLECTABLE); + } + *flh = GC_obj_link(op); + GC_aux::GC_uncollectable_words_recently_allocd += nwords; + return op; + } + static void deallocate(void *p, size_t n) + { + size_t nwords = GC_round_up_uncollectable(n); + void ** flh; + + if (n > GC_max_fast_bytes) { + GC_free(p); + } else { + flh = GC_uobjfreelist_ptr + nwords; + GC_obj_link(p) = *flh; + *flh = p; + GC_aux::GC_uncollectable_mem_recently_freed += nwords; + } + } + static void ptr_free_deallocate(void *p, size_t n) + { + size_t nwords = GC_round_up_uncollectable(n); + void ** flh; + + if (n > GC_max_fast_bytes) { + GC_free(p); + } else { + flh = GC_auobjfreelist_ptr + nwords; + GC_obj_link(p) = *flh; + *flh = p; + GC_aux::GC_uncollectable_mem_recently_freed += nwords; + } + } +}; + +typedef single_client_traceable_alloc_template<0> single_client_traceable_alloc; + +template < int dummy > +class gc_alloc_template { + public: + static void * allocate(size_t n) { return GC_malloc(n); } + static void * ptr_free_allocate(size_t n) + { return GC_malloc_atomic(n); } + static void deallocate(void *, size_t) { } + static void ptr_free_deallocate(void *, size_t) { } +}; + +typedef gc_alloc_template < 0 > gc_alloc; + +template < int dummy > +class traceable_alloc_template { + public: + static void * allocate(size_t n) { return GC_malloc_uncollectable(n); } + static void * ptr_free_allocate(size_t n) + { return GC_malloc_atomic_uncollectable(n); } + static void deallocate(void *p, size_t) { GC_free(p); } + static void ptr_free_deallocate(void *p, size_t) { GC_free(p); } +}; + +typedef traceable_alloc_template < 0 > traceable_alloc; + +#ifdef _SGI_SOURCE + +// We want to specialize simple_alloc so that it does the right thing +// for all pointerfree types. At the moment there is no portable way to +// even approximate that. The following approximation should work for +// SGI compilers, and perhaps some others. + +# define __GC_SPECIALIZE(T,alloc) \ +class simple_alloc<T, alloc> { \ +public: \ + static T *allocate(size_t n) \ + { return 0 == n? 0 : \ + (T*) alloc::ptr_free_allocate(n * sizeof (T)); } \ + static T *allocate(void) \ + { return (T*) alloc::ptr_free_allocate(sizeof (T)); } \ + static void deallocate(T *p, size_t n) \ + { if (0 != n) alloc::ptr_free_deallocate(p, n * sizeof (T)); } \ + static void deallocate(T *p) \ + { alloc::ptr_free_deallocate(p, sizeof (T)); } \ +}; + +__GC_SPECIALIZE(char, gc_alloc) +__GC_SPECIALIZE(int, gc_alloc) +__GC_SPECIALIZE(unsigned, gc_alloc) +__GC_SPECIALIZE(float, gc_alloc) +__GC_SPECIALIZE(double, gc_alloc) + +__GC_SPECIALIZE(char, traceable_alloc) +__GC_SPECIALIZE(int, traceable_alloc) +__GC_SPECIALIZE(unsigned, traceable_alloc) +__GC_SPECIALIZE(float, traceable_alloc) +__GC_SPECIALIZE(double, traceable_alloc) + +__GC_SPECIALIZE(char, single_client_gc_alloc) +__GC_SPECIALIZE(int, single_client_gc_alloc) +__GC_SPECIALIZE(unsigned, single_client_gc_alloc) +__GC_SPECIALIZE(float, single_client_gc_alloc) +__GC_SPECIALIZE(double, single_client_gc_alloc) + +__GC_SPECIALIZE(char, single_client_traceable_alloc) +__GC_SPECIALIZE(int, single_client_traceable_alloc) +__GC_SPECIALIZE(unsigned, single_client_traceable_alloc) +__GC_SPECIALIZE(float, single_client_traceable_alloc) +__GC_SPECIALIZE(double, single_client_traceable_alloc) + +#ifdef __STL_USE_STD_ALLOCATORS + +__STL_BEGIN_NAMESPACE + +template <class _T> +struct _Alloc_traits<_T, gc_alloc > +{ + static const bool _S_instanceless = true; + typedef simple_alloc<_T, gc_alloc > _Alloc_type; + typedef __allocator<_T, gc_alloc > allocator_type; +}; + +inline bool operator==(const gc_alloc&, + const gc_alloc&) +{ + return true; +} + +inline bool operator!=(const gc_alloc&, + const gc_alloc&) +{ + return false; +} + +template <class _T> +struct _Alloc_traits<_T, single_client_gc_alloc > +{ + static const bool _S_instanceless = true; + typedef simple_alloc<_T, single_client_gc_alloc > _Alloc_type; + typedef __allocator<_T, single_client_gc_alloc > allocator_type; +}; + +inline bool operator==(const single_client_gc_alloc&, + const single_client_gc_alloc&) +{ + return true; +} + +inline bool operator!=(const single_client_gc_alloc&, + const single_client_gc_alloc&) +{ + return false; +} + +template <class _T> +struct _Alloc_traits<_T, traceable_alloc > +{ + static const bool _S_instanceless = true; + typedef simple_alloc<_T, traceable_alloc > _Alloc_type; + typedef __allocator<_T, traceable_alloc > allocator_type; +}; + +inline bool operator==(const traceable_alloc&, + const traceable_alloc&) +{ + return true; +} + +inline bool operator!=(const traceable_alloc&, + const traceable_alloc&) +{ + return false; +} + +template <class _T> +struct _Alloc_traits<_T, single_client_traceable_alloc > +{ + static const bool _S_instanceless = true; + typedef simple_alloc<_T, single_client_traceable_alloc > _Alloc_type; + typedef __allocator<_T, single_client_traceable_alloc > allocator_type; +}; + +inline bool operator==(const single_client_traceable_alloc&, + const single_client_traceable_alloc&) +{ + return true; +} + +inline bool operator!=(const single_client_traceable_alloc&, + const single_client_traceable_alloc&) +{ + return false; +} + +__STL_END_NAMESPACE + +#endif /* __STL_USE_STD_ALLOCATORS */ + +#endif /* _SGI_SOURCE */ + +#endif /* GC_ALLOC_H */ diff --git a/gc/include/private/cord_pos.h b/gc/include/private/cord_pos.h new file mode 100644 index 0000000..d2b24bb --- /dev/null +++ b/gc/include/private/cord_pos.h @@ -0,0 +1,118 @@ +/* + * Copyright (c) 1993-1994 by Xerox Corporation. All rights reserved. + * + * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED + * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + * + * Permission is hereby granted to use or copy this program + * for any purpose, provided the above notices are retained on all copies. + * Permission to modify the code and to distribute modified code is granted, + * provided the above notices are retained, and a notice that the code was + * modified is included with the above copyright notice. + */ +/* Boehm, May 19, 1994 2:23 pm PDT */ +# ifndef CORD_POSITION_H + +/* The representation of CORD_position. This is private to the */ +/* implementation, but the size is known to clients. Also */ +/* the implementation of some exported macros relies on it. */ +/* Don't use anything defined here and not in cord.h. */ + +# define MAX_DEPTH 48 + /* The maximum depth of a balanced cord + 1. */ + /* We don't let cords get deeper than MAX_DEPTH. */ + +struct CORD_pe { + CORD pe_cord; + size_t pe_start_pos; +}; + +/* A structure describing an entry on the path from the root */ +/* to current position. */ +typedef struct CORD_Pos { + size_t cur_pos; + int path_len; +# define CORD_POS_INVALID (0x55555555) + /* path_len == INVALID <==> position invalid */ + const char *cur_leaf; /* Current leaf, if it is a string. */ + /* If the current leaf is a function, */ + /* then this may point to function_buf */ + /* containing the next few characters. */ + /* Always points to a valid string */ + /* containing the current character */ + /* unless cur_end is 0. */ + size_t cur_start; /* Start position of cur_leaf */ + size_t cur_end; /* Ending position of cur_leaf */ + /* 0 if cur_leaf is invalid. */ + struct CORD_pe path[MAX_DEPTH + 1]; + /* path[path_len] is the leaf corresponding to cur_pos */ + /* path[0].pe_cord is the cord we point to. */ +# define FUNCTION_BUF_SZ 8 + char function_buf[FUNCTION_BUF_SZ]; /* Space for next few chars */ + /* from function node. */ +} CORD_pos[1]; + +/* Extract the cord from a position: */ +CORD CORD_pos_to_cord(CORD_pos p); + +/* Extract the current index from a position: */ +size_t CORD_pos_to_index(CORD_pos p); + +/* Fetch the character located at the given position: */ +char CORD_pos_fetch(CORD_pos p); + +/* Initialize the position to refer to the give cord and index. */ +/* Note that this is the most expensive function on positions: */ +void CORD_set_pos(CORD_pos p, CORD x, size_t i); + +/* Advance the position to the next character. */ +/* P must be initialized and valid. */ +/* Invalidates p if past end: */ +void CORD_next(CORD_pos p); + +/* Move the position to the preceding character. */ +/* P must be initialized and valid. */ +/* Invalidates p if past beginning: */ +void CORD_prev(CORD_pos p); + +/* Is the position valid, i.e. inside the cord? */ +int CORD_pos_valid(CORD_pos p); + +char CORD__pos_fetch(CORD_pos); +void CORD__next(CORD_pos); +void CORD__prev(CORD_pos); + +#define CORD_pos_fetch(p) \ + (((p)[0].cur_end != 0)? \ + (p)[0].cur_leaf[(p)[0].cur_pos - (p)[0].cur_start] \ + : CORD__pos_fetch(p)) + +#define CORD_next(p) \ + (((p)[0].cur_pos + 1 < (p)[0].cur_end)? \ + (p)[0].cur_pos++ \ + : (CORD__next(p), 0)) + +#define CORD_prev(p) \ + (((p)[0].cur_end != 0 && (p)[0].cur_pos > (p)[0].cur_start)? \ + (p)[0].cur_pos-- \ + : (CORD__prev(p), 0)) + +#define CORD_pos_to_index(p) ((p)[0].cur_pos) + +#define CORD_pos_to_cord(p) ((p)[0].path[0].pe_cord) + +#define CORD_pos_valid(p) ((p)[0].path_len != CORD_POS_INVALID) + +/* Some grubby stuff for performance-critical friends: */ +#define CORD_pos_chars_left(p) ((long)((p)[0].cur_end) - (long)((p)[0].cur_pos)) + /* Number of characters in cache. <= 0 ==> none */ + +#define CORD_pos_advance(p,n) ((p)[0].cur_pos += (n) - 1, CORD_next(p)) + /* Advance position by n characters */ + /* 0 < n < CORD_pos_chars_left(p) */ + +#define CORD_pos_cur_char_addr(p) \ + (p)[0].cur_leaf + ((p)[0].cur_pos - (p)[0].cur_start) + /* address of current character in cache. */ + +#endif diff --git a/gc/include/private/gc_hdrs.h b/gc/include/private/gc_hdrs.h new file mode 100644 index 0000000..60dc2ad --- /dev/null +++ b/gc/include/private/gc_hdrs.h @@ -0,0 +1,135 @@ +/* + * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers + * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved. + * + * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED + * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + * + * Permission is hereby granted to use or copy this program + * for any purpose, provided the above notices are retained on all copies. + * Permission to modify the code and to distribute modified code is granted, + * provided the above notices are retained, and a notice that the code was + * modified is included with the above copyright notice. + */ +/* Boehm, July 11, 1995 11:54 am PDT */ +# ifndef GC_HEADERS_H +# define GC_HEADERS_H +typedef struct hblkhdr hdr; + +# if CPP_WORDSZ != 32 && CPP_WORDSZ < 36 + --> Get a real machine. +# endif + +/* + * The 2 level tree data structure that is used to find block headers. + * If there are more than 32 bits in a pointer, the top level is a hash + * table. + */ + +# if CPP_WORDSZ > 32 +# define HASH_TL +# endif + +/* Define appropriate out-degrees for each of the two tree levels */ +# ifdef SMALL_CONFIG +# define LOG_BOTTOM_SZ 11 + /* Keep top index size reasonable with smaller blocks. */ +# else +# define LOG_BOTTOM_SZ 10 +# endif +# ifndef HASH_TL +# define LOG_TOP_SZ (WORDSZ - LOG_BOTTOM_SZ - LOG_HBLKSIZE) +# else +# define LOG_TOP_SZ 11 +# endif +# define TOP_SZ (1 << LOG_TOP_SZ) +# define BOTTOM_SZ (1 << LOG_BOTTOM_SZ) + +typedef struct bi { + hdr * index[BOTTOM_SZ]; + /* + * The bottom level index contains one of three kinds of values: + * 0 means we're not responsible for this block, + * or this is a block other than the first one in a free block. + * 1 < (long)X <= MAX_JUMP means the block starts at least + * X * HBLKSIZE bytes before the current address. + * A valid pointer points to a hdr structure. (The above can't be + * valid pointers due to the GET_MEM return convention.) + */ + struct bi * asc_link; /* All indices are linked in */ + /* ascending order... */ + struct bi * desc_link; /* ... and in descending order. */ + word key; /* high order address bits. */ +# ifdef HASH_TL + struct bi * hash_link; /* Hash chain link. */ +# endif +} bottom_index; + +/* extern bottom_index GC_all_nils; - really part of GC_arrays */ + +/* extern bottom_index * GC_top_index []; - really part of GC_arrays */ + /* Each entry points to a bottom_index. */ + /* On a 32 bit machine, it points to */ + /* the index for a set of high order */ + /* bits equal to the index. For longer */ + /* addresses, we hash the high order */ + /* bits to compute the index in */ + /* GC_top_index, and each entry points */ + /* to a hash chain. */ + /* The last entry in each chain is */ + /* GC_all_nils. */ + + +# define MAX_JUMP (HBLKSIZE - 1) + +# define HDR_FROM_BI(bi, p) \ + ((bi)->index[((word)(p) >> LOG_HBLKSIZE) & (BOTTOM_SZ - 1)]) +# ifndef HASH_TL +# define BI(p) (GC_top_index \ + [(word)(p) >> (LOG_BOTTOM_SZ + LOG_HBLKSIZE)]) +# define HDR_INNER(p) HDR_FROM_BI(BI(p),p) +# ifdef SMALL_CONFIG +# define HDR(p) GC_find_header((ptr_t)(p)) +# else +# define HDR(p) HDR_INNER(p) +# endif +# define GET_BI(p, bottom_indx) (bottom_indx) = BI(p) +# define GET_HDR(p, hhdr) (hhdr) = HDR(p) +# define SET_HDR(p, hhdr) HDR_INNER(p) = (hhdr) +# define GET_HDR_ADDR(p, ha) (ha) = &(HDR_INNER(p)) +# else /* hash */ +/* Hash function for tree top level */ +# define TL_HASH(hi) ((hi) & (TOP_SZ - 1)) +/* Set bottom_indx to point to the bottom index for address p */ +# define GET_BI(p, bottom_indx) \ + { \ + register word hi = \ + (word)(p) >> (LOG_BOTTOM_SZ + LOG_HBLKSIZE); \ + register bottom_index * _bi = GC_top_index[TL_HASH(hi)]; \ + \ + while (_bi -> key != hi && _bi != GC_all_nils) \ + _bi = _bi -> hash_link; \ + (bottom_indx) = _bi; \ + } +# define GET_HDR_ADDR(p, ha) \ + { \ + register bottom_index * bi; \ + \ + GET_BI(p, bi); \ + (ha) = &(HDR_FROM_BI(bi, p)); \ + } +# define GET_HDR(p, hhdr) { register hdr ** _ha; GET_HDR_ADDR(p, _ha); \ + (hhdr) = *_ha; } +# define SET_HDR(p, hhdr) { register hdr ** _ha; GET_HDR_ADDR(p, _ha); \ + *_ha = (hhdr); } +# define HDR(p) GC_find_header((ptr_t)(p)) +# endif + +/* Is the result a forwarding address to someplace closer to the */ +/* beginning of the block or NIL? */ +# define IS_FORWARDING_ADDR_OR_NIL(hhdr) ((unsigned long) (hhdr) <= MAX_JUMP) + +/* Get an HBLKSIZE aligned address closer to the beginning of the block */ +/* h. Assumes hhdr == HDR(h) and IS_FORWARDING_ADDR(hhdr). */ +# define FORWARDED_ADDR(h, hhdr) ((struct hblk *)(h) - (unsigned long)(hhdr)) +# endif /* GC_HEADERS_H */ diff --git a/gc/include/private/gc_priv.h b/gc/include/private/gc_priv.h new file mode 100644 index 0000000..5ce52a7 --- /dev/null +++ b/gc/include/private/gc_priv.h @@ -0,0 +1,1748 @@ +/* + * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers + * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved. + * + * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED + * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + * + * Permission is hereby granted to use or copy this program + * for any purpose, provided the above notices are retained on all copies. + * Permission to modify the code and to distribute modified code is granted, + * provided the above notices are retained, and a notice that the code was + * modified is included with the above copyright notice. + */ +/* Boehm, February 16, 1996 2:30 pm PST */ + + +# ifndef GC_PRIVATE_H +# define GC_PRIVATE_H + +#if defined(mips) && defined(SYSTYPE_BSD) && defined(sony_news) + /* sony RISC NEWS, NEWSOS 4 */ +# define BSD_TIME +/* typedef long ptrdiff_t; -- necessary on some really old systems */ +#endif + +#if defined(mips) && defined(SYSTYPE_BSD43) + /* MIPS RISCOS 4 */ +# define BSD_TIME +#endif + +#ifdef BSD_TIME +# include <sys/types.h> +# include <sys/time.h> +# include <sys/resource.h> +#endif /* BSD_TIME */ + +# ifndef GC_H +# include "gc.h" +# endif + +typedef GC_word word; +typedef GC_signed_word signed_word; + +# ifndef CONFIG_H +# include "gcconfig.h" +# endif + +# ifndef HEADERS_H +# include "gc_hdrs.h" +# endif + +typedef int GC_bool; +# define TRUE 1 +# define FALSE 0 + +typedef char * ptr_t; /* A generic pointer to which we can add */ + /* byte displacements. */ + /* Preferably identical to caddr_t, if it */ + /* exists. */ + +#if defined(__STDC__) +# include <stdlib.h> +# if !(defined( sony_news ) ) +# include <stddef.h> +# endif +# define VOLATILE volatile +# define CONST const +#else +# ifdef MSWIN32 +# include <stdlib.h> +# endif +# define VOLATILE +# define CONST +#endif + +#if 0 /* was once defined for AMIGA */ +# define GC_FAR __far +#else +# define GC_FAR +#endif + +/*********************************/ +/* */ +/* Definitions for conservative */ +/* collector */ +/* */ +/*********************************/ + +/*********************************/ +/* */ +/* Easily changeable parameters */ +/* */ +/*********************************/ + +#define STUBBORN_ALLOC /* Define stubborn allocation primitives */ +#if defined(SRC_M3) || defined(SMALL_CONFIG) +# undef STUBBORN_ALLOC +#endif + + +/* #define ALL_INTERIOR_POINTERS */ + /* Forces all pointers into the interior of an */ + /* object to be considered valid. Also causes the */ + /* sizes of all objects to be inflated by at least */ + /* one byte. This should suffice to guarantee */ + /* that in the presence of a compiler that does */ + /* not perform garbage-collector-unsafe */ + /* optimizations, all portable, strictly ANSI */ + /* conforming C programs should be safely usable */ + /* with malloc replaced by GC_malloc and free */ + /* calls removed. There are several disadvantages: */ + /* 1. There are probably no interesting, portable, */ + /* strictly ANSI conforming C programs. */ + /* 2. This option makes it hard for the collector */ + /* to allocate space that is not ``pointed to'' */ + /* by integers, etc. Under SunOS 4.X with a */ + /* statically linked libc, we empiricaly */ + /* observed that it would be difficult to */ + /* allocate individual objects larger than 100K. */ + /* Even if only smaller objects are allocated, */ + /* more swap space is likely to be needed. */ + /* Fortunately, much of this will never be */ + /* touched. */ + /* If you can easily avoid using this option, do. */ + /* If not, try to keep individual objects small. */ + +#define PRINTSTATS /* Print garbage collection statistics */ + /* For less verbose output, undefine in reclaim.c */ + +#define PRINTTIMES /* Print the amount of time consumed by each garbage */ + /* collection. */ + +#define PRINTBLOCKS /* Print object sizes associated with heap blocks, */ + /* whether the objects are atomic or composite, and */ + /* whether or not the block was found to be empty */ + /* during the reclaim phase. Typically generates */ + /* about one screenful per garbage collection. */ +#undef PRINTBLOCKS + +#ifdef SILENT +# ifdef PRINTSTATS +# undef PRINTSTATS +# endif +# ifdef PRINTTIMES +# undef PRINTTIMES +# endif +# ifdef PRINTNBLOCKS +# undef PRINTNBLOCKS +# endif +#endif + +#if defined(PRINTSTATS) && !defined(GATHERSTATS) +# define GATHERSTATS +#endif + +#ifdef FINALIZE_ON_DEMAND +# define GC_INVOKE_FINALIZERS() +#else +# define GC_INVOKE_FINALIZERS() (void)GC_invoke_finalizers() +#endif + +#define MERGE_SIZES /* Round up some object sizes, so that fewer distinct */ + /* free lists are actually maintained. This applies */ + /* only to the top level routines in misc.c, not to */ + /* user generated code that calls GC_allocobj and */ + /* GC_allocaobj directly. */ + /* Slows down average programs slightly. May however */ + /* substantially reduce fragmentation if allocation */ + /* request sizes are widely scattered. */ + /* May save significant amounts of space for obj_map */ + /* entries. */ + +#ifndef OLD_BLOCK_ALLOC + /* Macros controlling large block allocation strategy. */ +# define EXACT_FIRST /* Make a complete pass through the large object */ + /* free list before splitting a block */ +# define PRESERVE_LAST /* Do not divide last allocated heap segment */ + /* unless we would otherwise need to expand the */ + /* heap. */ +#endif + +/* ALIGN_DOUBLE requires MERGE_SIZES at present. */ +# if defined(ALIGN_DOUBLE) && !defined(MERGE_SIZES) +# define MERGE_SIZES +# endif + +#if defined(ALL_INTERIOR_POINTERS) && !defined(DONT_ADD_BYTE_AT_END) +# define ADD_BYTE_AT_END +#endif + + +# ifndef LARGE_CONFIG +# define MINHINCR 16 /* Minimum heap increment, in blocks of HBLKSIZE */ + /* Must be multiple of largest page size. */ +# define MAXHINCR 512 /* Maximum heap increment, in blocks */ +# else +# define MINHINCR 64 +# define MAXHINCR 4096 +# endif + +# define TIME_LIMIT 50 /* We try to keep pause times from exceeding */ + /* this by much. In milliseconds. */ + +# define BL_LIMIT GC_black_list_spacing + /* If we need a block of N bytes, and we have */ + /* a block of N + BL_LIMIT bytes available, */ + /* and N > BL_LIMIT, */ + /* but all possible positions in it are */ + /* blacklisted, we just use it anyway (and */ + /* print a warning, if warnings are enabled). */ + /* This risks subsequently leaking the block */ + /* due to a false reference. But not using */ + /* the block risks unreasonable immediate */ + /* heap growth. */ + +/*********************************/ +/* */ +/* Stack saving for debugging */ +/* */ +/*********************************/ + +#ifdef SAVE_CALL_CHAIN + +/* + * Number of frames and arguments to save in objects allocated by + * debugging allocator. + */ +# define NFRAMES 6 /* Number of frames to save. Even for */ + /* alignment reasons. */ +# define NARGS 2 /* Mumber of arguments to save for each call. */ + +# define NEED_CALLINFO + +/* Fill in the pc and argument information for up to NFRAMES of my */ +/* callers. Ignore my frame and my callers frame. */ +void GC_save_callers (/* struct callinfo info[NFRAMES] */); + +void GC_print_callers (/* struct callinfo info[NFRAMES] */); + +#else + +# ifdef GC_ADD_CALLER +# define NFRAMES 1 +# define NARGS 0 +# define NEED_CALLINFO +# endif + +#endif + +#ifdef NEED_CALLINFO + struct callinfo { + word ci_pc; +# if NARGS > 0 + word ci_arg[NARGS]; /* bit-wise complement to avoid retention */ +# endif +# if defined(ALIGN_DOUBLE) && (NFRAMES * (NARGS + 1)) % 2 == 1 + /* Likely alignment problem. */ + word ci_dummy; +# endif + }; +#endif + + +/*********************************/ +/* */ +/* OS interface routines */ +/* */ +/*********************************/ + +#ifdef BSD_TIME +# undef CLOCK_TYPE +# undef GET_TIME +# undef MS_TIME_DIFF +# define CLOCK_TYPE struct timeval +# define GET_TIME(x) { struct rusage rusage; \ + getrusage (RUSAGE_SELF, &rusage); \ + x = rusage.ru_utime; } +# define MS_TIME_DIFF(a,b) ((double) (a.tv_sec - b.tv_sec) * 1000.0 \ + + (double) (a.tv_usec - b.tv_usec) / 1000.0) +#else /* !BSD_TIME */ +# include <time.h> +# if !defined(__STDC__) && defined(SPARC) && defined(SUNOS4) + clock_t clock(); /* Not in time.h, where it belongs */ +# endif +# if defined(FREEBSD) && !defined(CLOCKS_PER_SEC) +# include <machine/limits.h> +# define CLOCKS_PER_SEC CLK_TCK +# endif +# if !defined(CLOCKS_PER_SEC) +# define CLOCKS_PER_SEC 1000000 +/* + * This is technically a bug in the implementation. ANSI requires that + * CLOCKS_PER_SEC be defined. But at least under SunOS4.1.1, it isn't. + * Also note that the combination of ANSI C and POSIX is incredibly gross + * here. The type clock_t is used by both clock() and times(). But on + * some machines these use different notions of a clock tick, CLOCKS_PER_SEC + * seems to apply only to clock. Hence we use it here. On many machines, + * including SunOS, clock actually uses units of microseconds (which are + * not really clock ticks). + */ +# endif +# define CLOCK_TYPE clock_t +# define GET_TIME(x) x = clock() +# define MS_TIME_DIFF(a,b) ((unsigned long) \ + (1000.0*(double)((a)-(b))/(double)CLOCKS_PER_SEC)) +#endif /* !BSD_TIME */ + +/* We use bzero and bcopy internally. They may not be available. */ +# if defined(SPARC) && defined(SUNOS4) +# define BCOPY_EXISTS +# endif +# if defined(M68K) && defined(AMIGA) +# define BCOPY_EXISTS +# endif +# if defined(M68K) && defined(NEXT) +# define BCOPY_EXISTS +# endif +# if defined(VAX) +# define BCOPY_EXISTS +# endif +# if defined(AMIGA) +# include <string.h> +# define BCOPY_EXISTS +# endif + +# ifndef BCOPY_EXISTS +# include <string.h> +# define BCOPY(x,y,n) memcpy(y, x, (size_t)(n)) +# define BZERO(x,n) memset(x, 0, (size_t)(n)) +# else +# define BCOPY(x,y,n) bcopy((char *)(x),(char *)(y),(int)(n)) +# define BZERO(x,n) bzero((char *)(x),(int)(n)) +# endif + +/* HBLKSIZE aligned allocation. 0 is taken to mean failure */ +/* space is assumed to be cleared. */ +/* In the case os USE_MMAP, the argument must also be a */ +/* physical page size. */ +/* GET_MEM is currently not assumed to retrieve 0 filled space, */ +/* though we should perhaps take advantage of the case in which */ +/* does. */ +# ifdef PCR + char * real_malloc(); +# define GET_MEM(bytes) HBLKPTR(real_malloc((size_t)bytes + GC_page_size) \ + + GC_page_size-1) +# else +# ifdef OS2 + void * os2_alloc(size_t bytes); +# define GET_MEM(bytes) HBLKPTR((ptr_t)os2_alloc((size_t)bytes \ + + GC_page_size) \ + + GC_page_size-1) +# else +# if defined(AMIGA) || defined(NEXT) || defined(MACOSX) || defined(DOS4GW) +# define GET_MEM(bytes) HBLKPTR((size_t) \ + calloc(1, (size_t)bytes + GC_page_size) \ + + GC_page_size-1) +# else +# ifdef MSWIN32 + extern ptr_t GC_win32_get_mem(); +# define GET_MEM(bytes) (struct hblk *)GC_win32_get_mem(bytes) +# else +# ifdef MACOS +# if defined(USE_TEMPORARY_MEMORY) + extern Ptr GC_MacTemporaryNewPtr(size_t size, + Boolean clearMemory); +# define GET_MEM(bytes) HBLKPTR( \ + GC_MacTemporaryNewPtr(bytes + GC_page_size, true) \ + + GC_page_size-1) +# else +# define GET_MEM(bytes) HBLKPTR( \ + NewPtrClear(bytes + GC_page_size) + GC_page_size-1) +# endif +# else + extern ptr_t GC_unix_get_mem(); +# define GET_MEM(bytes) (struct hblk *)GC_unix_get_mem(bytes) +# endif +# endif +# endif +# endif +# endif + +/* + * Mutual exclusion between allocator/collector routines. + * Needed if there is more than one allocator thread. + * FASTLOCK() is assumed to try to acquire the lock in a cheap and + * dirty way that is acceptable for a few instructions, e.g. by + * inhibiting preemption. This is assumed to have succeeded only + * if a subsequent call to FASTLOCK_SUCCEEDED() returns TRUE. + * FASTUNLOCK() is called whether or not FASTLOCK_SUCCEEDED(). + * If signals cannot be tolerated with the FASTLOCK held, then + * FASTLOCK should disable signals. The code executed under + * FASTLOCK is otherwise immune to interruption, provided it is + * not restarted. + * DCL_LOCK_STATE declares any local variables needed by LOCK and UNLOCK + * and/or DISABLE_SIGNALS and ENABLE_SIGNALS and/or FASTLOCK. + * (There is currently no equivalent for FASTLOCK.) + */ +# ifdef THREADS +# ifdef PCR_OBSOLETE /* Faster, but broken with multiple lwp's */ +# include "th/PCR_Th.h" +# include "th/PCR_ThCrSec.h" + extern struct PCR_Th_MLRep GC_allocate_ml; +# define DCL_LOCK_STATE PCR_sigset_t GC_old_sig_mask +# define LOCK() PCR_Th_ML_Acquire(&GC_allocate_ml) +# define UNLOCK() PCR_Th_ML_Release(&GC_allocate_ml) +# define FASTLOCK() PCR_ThCrSec_EnterSys() + /* Here we cheat (a lot): */ +# define FASTLOCK_SUCCEEDED() (*(int *)(&GC_allocate_ml) == 0) + /* TRUE if nobody currently holds the lock */ +# define FASTUNLOCK() PCR_ThCrSec_ExitSys() +# endif +# ifdef PCR +# include <base/PCR_Base.h> +# include <th/PCR_Th.h> + extern PCR_Th_ML GC_allocate_ml; +# define DCL_LOCK_STATE \ + PCR_ERes GC_fastLockRes; PCR_sigset_t GC_old_sig_mask +# define LOCK() PCR_Th_ML_Acquire(&GC_allocate_ml) +# define UNLOCK() PCR_Th_ML_Release(&GC_allocate_ml) +# define FASTLOCK() (GC_fastLockRes = PCR_Th_ML_Try(&GC_allocate_ml)) +# define FASTLOCK_SUCCEEDED() (GC_fastLockRes == PCR_ERes_okay) +# define FASTUNLOCK() {\ + if( FASTLOCK_SUCCEEDED() ) PCR_Th_ML_Release(&GC_allocate_ml); } +# endif +# ifdef SRC_M3 + extern word RT0u__inCritical; +# define LOCK() RT0u__inCritical++ +# define UNLOCK() RT0u__inCritical-- +# endif +# ifdef SOLARIS_THREADS +# include <thread.h> +# include <signal.h> + extern mutex_t GC_allocate_ml; +# define LOCK() mutex_lock(&GC_allocate_ml); +# define UNLOCK() mutex_unlock(&GC_allocate_ml); +# endif +# ifdef LINUX_THREADS +# include <pthread.h> +# ifdef __i386__ + inline static int GC_test_and_set(volatile unsigned int *addr) { + int oldval; + /* Note: the "xchg" instruction does not need a "lock" prefix */ + __asm__ __volatile__("xchgl %0, %1" + : "=r"(oldval), "=m"(*(addr)) + : "0"(1), "m"(*(addr))); + return oldval; + } +# else + -- > Need implementation of GC_test_and_set() +# endif +# define GC_clear(addr) (*(addr) = 0) + + extern volatile unsigned int GC_allocate_lock; + /* This is not a mutex because mutexes that obey the (optional) */ + /* POSIX scheduling rules are subject to convoys in high contention */ + /* applications. This is basically a spin lock. */ + extern pthread_t GC_lock_holder; + extern void GC_lock(void); + /* Allocation lock holder. Only set if acquired by client through */ + /* GC_call_with_alloc_lock. */ +# define SET_LOCK_HOLDER() GC_lock_holder = pthread_self() +# define NO_THREAD (pthread_t)(-1) +# define UNSET_LOCK_HOLDER() GC_lock_holder = NO_THREAD +# define I_HOLD_LOCK() (pthread_equal(GC_lock_holder, pthread_self())) +# ifdef UNDEFINED +# define LOCK() pthread_mutex_lock(&GC_allocate_ml) +# define UNLOCK() pthread_mutex_unlock(&GC_allocate_ml) +# else +# define LOCK() \ + { if (GC_test_and_set(&GC_allocate_lock)) GC_lock(); } +# define UNLOCK() \ + GC_clear(&GC_allocate_lock) +# endif + extern GC_bool GC_collecting; +# define ENTER_GC() \ + { \ + GC_collecting = 1; \ + } +# define EXIT_GC() GC_collecting = 0; +# endif /* LINUX_THREADS */ +# if defined(IRIX_THREADS) || defined(IRIX_JDK_THREADS) +# include <pthread.h> +# include <mutex.h> + +# if __mips < 3 || !(defined (_ABIN32) || defined(_ABI64)) \ + || !defined(_COMPILER_VERSION) || _COMPILER_VERSION < 700 +# define GC_test_and_set(addr, v) test_and_set(addr,v) +# else +# define GC_test_and_set(addr, v) __test_and_set(addr,v) +# endif + extern unsigned long GC_allocate_lock; + /* This is not a mutex because mutexes that obey the (optional) */ + /* POSIX scheduling rules are subject to convoys in high contention */ + /* applications. This is basically a spin lock. */ + extern pthread_t GC_lock_holder; + extern void GC_lock(void); + /* Allocation lock holder. Only set if acquired by client through */ + /* GC_call_with_alloc_lock. */ +# define SET_LOCK_HOLDER() GC_lock_holder = pthread_self() +# define NO_THREAD (pthread_t)(-1) +# define UNSET_LOCK_HOLDER() GC_lock_holder = NO_THREAD +# define I_HOLD_LOCK() (pthread_equal(GC_lock_holder, pthread_self())) +# ifdef UNDEFINED +# define LOCK() pthread_mutex_lock(&GC_allocate_ml) +# define UNLOCK() pthread_mutex_unlock(&GC_allocate_ml) +# else +# define LOCK() { if (GC_test_and_set(&GC_allocate_lock, 1)) GC_lock(); } +# if __mips >= 3 && (defined (_ABIN32) || defined(_ABI64)) \ + && defined(_COMPILER_VERSION) && _COMPILER_VERSION >= 700 +# define UNLOCK() __lock_release(&GC_allocate_lock) +# else + /* The function call in the following should prevent the */ + /* compiler from moving assignments to below the UNLOCK. */ + /* This is probably not necessary for ucode or gcc 2.8. */ + /* It may be necessary for Ragnarok and future gcc */ + /* versions. */ +# define UNLOCK() { GC_noop1(&GC_allocate_lock); \ + *(volatile unsigned long *)(&GC_allocate_lock) = 0; } +# endif +# endif + extern GC_bool GC_collecting; +# define ENTER_GC() \ + { \ + GC_collecting = 1; \ + } +# define EXIT_GC() GC_collecting = 0; +# endif /* IRIX_THREADS || IRIX_JDK_THREADS */ +# ifdef WIN32_THREADS +# include <windows.h> + GC_API CRITICAL_SECTION GC_allocate_ml; +# define LOCK() EnterCriticalSection(&GC_allocate_ml); +# define UNLOCK() LeaveCriticalSection(&GC_allocate_ml); +# endif +# ifndef SET_LOCK_HOLDER +# define SET_LOCK_HOLDER() +# define UNSET_LOCK_HOLDER() +# define I_HOLD_LOCK() FALSE + /* Used on platforms were locks can be reacquired, */ + /* so it doesn't matter if we lie. */ +# endif +# else +# define LOCK() +# define UNLOCK() +# endif +# ifndef SET_LOCK_HOLDER +# define SET_LOCK_HOLDER() +# define UNSET_LOCK_HOLDER() +# define I_HOLD_LOCK() FALSE + /* Used on platforms were locks can be reacquired, */ + /* so it doesn't matter if we lie. */ +# endif +# ifndef ENTER_GC +# define ENTER_GC() +# define EXIT_GC() +# endif + +# ifndef DCL_LOCK_STATE +# define DCL_LOCK_STATE +# endif +# ifndef FASTLOCK +# define FASTLOCK() LOCK() +# define FASTLOCK_SUCCEEDED() TRUE +# define FASTUNLOCK() UNLOCK() +# endif + +/* Delay any interrupts or signals that may abort this thread. Data */ +/* structures are in a consistent state outside this pair of calls. */ +/* ANSI C allows both to be empty (though the standard isn't very */ +/* clear on that point). Standard malloc implementations are usually */ +/* neither interruptable nor thread-safe, and thus correspond to */ +/* empty definitions. */ +# ifdef PCR +# define DISABLE_SIGNALS() \ + PCR_Th_SetSigMask(PCR_allSigsBlocked,&GC_old_sig_mask) +# define ENABLE_SIGNALS() \ + PCR_Th_SetSigMask(&GC_old_sig_mask, NIL) +# else +# if defined(SRC_M3) || defined(AMIGA) || defined(SOLARIS_THREADS) \ + || defined(MSWIN32) || defined(MACOS) || defined(DJGPP) \ + || defined(NO_SIGNALS) || defined(IRIX_THREADS) \ + || defined(IRIX_JDK_THREADS) || defined(LINUX_THREADS) + /* Also useful for debugging. */ + /* Should probably use thr_sigsetmask for SOLARIS_THREADS. */ +# define DISABLE_SIGNALS() +# define ENABLE_SIGNALS() +# else +# define DISABLE_SIGNALS() GC_disable_signals() + void GC_disable_signals(); +# define ENABLE_SIGNALS() GC_enable_signals() + void GC_enable_signals(); +# endif +# endif + +/* + * Stop and restart mutator threads. + */ +# ifdef PCR +# include "th/PCR_ThCtl.h" +# define STOP_WORLD() \ + PCR_ThCtl_SetExclusiveMode(PCR_ThCtl_ExclusiveMode_stopNormal, \ + PCR_allSigsBlocked, \ + PCR_waitForever) +# define START_WORLD() \ + PCR_ThCtl_SetExclusiveMode(PCR_ThCtl_ExclusiveMode_null, \ + PCR_allSigsBlocked, \ + PCR_waitForever); +# else +# if defined(SOLARIS_THREADS) || defined(WIN32_THREADS) \ + || defined(IRIX_THREADS) || defined(LINUX_THREADS) \ + || defined(IRIX_JDK_THREADS) + void GC_stop_world(); + void GC_start_world(); +# define STOP_WORLD() GC_stop_world() +# define START_WORLD() GC_start_world() +# else +# define STOP_WORLD() +# define START_WORLD() +# endif +# endif + +/* Abandon ship */ +# ifdef PCR +# define ABORT(s) PCR_Base_Panic(s) +# else +# ifdef SMALL_CONFIG +# define ABORT(msg) abort(); +# else + GC_API void GC_abort(); +# define ABORT(msg) GC_abort(msg); +# endif +# endif + +/* Exit abnormally, but without making a mess (e.g. out of memory) */ +# ifdef PCR +# define EXIT() PCR_Base_Exit(1,PCR_waitForever) +# else +# define EXIT() (void)exit(1) +# endif + +/* Print warning message, e.g. almost out of memory. */ +# define WARN(msg,arg) (*GC_current_warn_proc)(msg, (GC_word)(arg)) +extern GC_warn_proc GC_current_warn_proc; + +/*********************************/ +/* */ +/* Word-size-dependent defines */ +/* */ +/*********************************/ + +#if CPP_WORDSZ == 32 +# define WORDS_TO_BYTES(x) ((x)<<2) +# define BYTES_TO_WORDS(x) ((x)>>2) +# define LOGWL ((word)5) /* log[2] of CPP_WORDSZ */ +# define modWORDSZ(n) ((n) & 0x1f) /* n mod size of word */ +# if ALIGNMENT != 4 +# define UNALIGNED +# endif +#endif + +#if CPP_WORDSZ == 64 +# define WORDS_TO_BYTES(x) ((x)<<3) +# define BYTES_TO_WORDS(x) ((x)>>3) +# define LOGWL ((word)6) /* log[2] of CPP_WORDSZ */ +# define modWORDSZ(n) ((n) & 0x3f) /* n mod size of word */ +# if ALIGNMENT != 8 +# define UNALIGNED +# endif +#endif + +#define WORDSZ ((word)CPP_WORDSZ) +#define SIGNB ((word)1 << (WORDSZ-1)) +#define BYTES_PER_WORD ((word)(sizeof (word))) +#define ONES ((word)(-1)) +#define divWORDSZ(n) ((n) >> LOGWL) /* divide n by size of word */ + +/*********************/ +/* */ +/* Size Parameters */ +/* */ +/*********************/ + +/* heap block size, bytes. Should be power of 2 */ + +#ifndef HBLKSIZE +# ifdef SMALL_CONFIG +# define CPP_LOG_HBLKSIZE 10 +# else +# if CPP_WORDSZ == 32 +# define CPP_LOG_HBLKSIZE 12 +# else +# define CPP_LOG_HBLKSIZE 13 +# endif +# endif +#else +# if HBLKSIZE == 512 +# define CPP_LOG_HBLKSIZE 9 +# endif +# if HBLKSIZE == 1024 +# define CPP_LOG_HBLKSIZE 10 +# endif +# if HBLKSIZE == 2048 +# define CPP_LOG_HBLKSIZE 11 +# endif +# if HBLKSIZE == 4096 +# define CPP_LOG_HBLKSIZE 12 +# endif +# if HBLKSIZE == 8192 +# define CPP_LOG_HBLKSIZE 13 +# endif +# if HBLKSIZE == 16384 +# define CPP_LOG_HBLKSIZE 14 +# endif +# ifndef CPP_LOG_HBLKSIZE + --> fix HBLKSIZE +# endif +# undef HBLKSIZE +#endif +# define CPP_HBLKSIZE (1 << CPP_LOG_HBLKSIZE) +# define LOG_HBLKSIZE ((word)CPP_LOG_HBLKSIZE) +# define HBLKSIZE ((word)CPP_HBLKSIZE) + + +/* max size objects supported by freelist (larger objects may be */ +/* allocated, but less efficiently) */ + +#define CPP_MAXOBJSZ BYTES_TO_WORDS(CPP_HBLKSIZE/2) +#define MAXOBJSZ ((word)CPP_MAXOBJSZ) + +# define divHBLKSZ(n) ((n) >> LOG_HBLKSIZE) + +# define HBLK_PTR_DIFF(p,q) divHBLKSZ((ptr_t)p - (ptr_t)q) + /* Equivalent to subtracting 2 hblk pointers. */ + /* We do it this way because a compiler should */ + /* find it hard to use an integer division */ + /* instead of a shift. The bundled SunOS 4.1 */ + /* o.w. sometimes pessimizes the subtraction to */ + /* involve a call to .div. */ + +# define modHBLKSZ(n) ((n) & (HBLKSIZE-1)) + +# define HBLKPTR(objptr) ((struct hblk *)(((word) (objptr)) & ~(HBLKSIZE-1))) + +# define HBLKDISPL(objptr) (((word) (objptr)) & (HBLKSIZE-1)) + +/* Round up byte allocation requests to integral number of words, etc. */ +# ifdef ADD_BYTE_AT_END +# define ROUNDED_UP_WORDS(n) BYTES_TO_WORDS((n) + WORDS_TO_BYTES(1)) +# ifdef ALIGN_DOUBLE +# define ALIGNED_WORDS(n) (BYTES_TO_WORDS((n) + WORDS_TO_BYTES(2)) & ~1) +# else +# define ALIGNED_WORDS(n) ROUNDED_UP_WORDS(n) +# endif +# define SMALL_OBJ(bytes) ((bytes) < WORDS_TO_BYTES(MAXOBJSZ)) +# define ADD_SLOP(bytes) ((bytes)+1) +# else +# define ROUNDED_UP_WORDS(n) BYTES_TO_WORDS((n) + (WORDS_TO_BYTES(1) - 1)) +# ifdef ALIGN_DOUBLE +# define ALIGNED_WORDS(n) \ + (BYTES_TO_WORDS((n) + WORDS_TO_BYTES(2) - 1) & ~1) +# else +# define ALIGNED_WORDS(n) ROUNDED_UP_WORDS(n) +# endif +# define SMALL_OBJ(bytes) ((bytes) <= WORDS_TO_BYTES(MAXOBJSZ)) +# define ADD_SLOP(bytes) (bytes) +# endif + + +/* + * Hash table representation of sets of pages. This assumes it is + * OK to add spurious entries to sets. + * Used by black-listing code, and perhaps by dirty bit maintenance code. + */ + +# ifdef LARGE_CONFIG +# define LOG_PHT_ENTRIES 17 +# else +# define LOG_PHT_ENTRIES 14 /* Collisions are likely if heap grows */ + /* to more than 16K hblks = 64MB. */ + /* Each hash table occupies 2K bytes. */ +# endif +# define PHT_ENTRIES ((word)1 << LOG_PHT_ENTRIES) +# define PHT_SIZE (PHT_ENTRIES >> LOGWL) +typedef word page_hash_table[PHT_SIZE]; + +# define PHT_HASH(addr) ((((word)(addr)) >> LOG_HBLKSIZE) & (PHT_ENTRIES - 1)) + +# define get_pht_entry_from_index(bl, index) \ + (((bl)[divWORDSZ(index)] >> modWORDSZ(index)) & 1) +# define set_pht_entry_from_index(bl, index) \ + (bl)[divWORDSZ(index)] |= (word)1 << modWORDSZ(index) +# define clear_pht_entry_from_index(bl, index) \ + (bl)[divWORDSZ(index)] &= ~((word)1 << modWORDSZ(index)) + + + +/********************************************/ +/* */ +/* H e a p B l o c k s */ +/* */ +/********************************************/ + +/* heap block header */ +#define HBLKMASK (HBLKSIZE-1) + +#define BITS_PER_HBLK (HBLKSIZE * 8) + +#define MARK_BITS_PER_HBLK (BITS_PER_HBLK/CPP_WORDSZ) + /* upper bound */ + /* We allocate 1 bit/word. Only the first word */ + /* in each object is actually marked. */ + +# ifdef ALIGN_DOUBLE +# define MARK_BITS_SZ (((MARK_BITS_PER_HBLK + 2*CPP_WORDSZ - 1) \ + / (2*CPP_WORDSZ))*2) +# else +# define MARK_BITS_SZ ((MARK_BITS_PER_HBLK + CPP_WORDSZ - 1)/CPP_WORDSZ) +# endif + /* Upper bound on number of mark words per heap block */ + +struct hblkhdr { + word hb_sz; /* If in use, size in words, of objects in the block. */ + /* if free, the size in bytes of the whole block */ + struct hblk * hb_next; /* Link field for hblk free list */ + /* and for lists of chunks waiting to be */ + /* reclaimed. */ + struct hblk * hb_prev; /* Backwards link for free list. */ + word hb_descr; /* object descriptor for marking. See */ + /* mark.h. */ + char* hb_map; /* A pointer to a pointer validity map of the block. */ + /* See GC_obj_map. */ + /* Valid for all blocks with headers. */ + /* Free blocks point to GC_invalid_map. */ + unsigned char hb_obj_kind; + /* Kind of objects in the block. Each kind */ + /* identifies a mark procedure and a set of */ + /* list headers. Sometimes called regions. */ + unsigned char hb_flags; +# define IGNORE_OFF_PAGE 1 /* Ignore pointers that do not */ + /* point to the first page of */ + /* this object. */ +# define WAS_UNMAPPED 2 /* This is a free block, which has */ + /* been unmapped from the address */ + /* space. */ + /* GC_remap must be invoked on it */ + /* before it can be reallocated. */ + /* Only set with USE_MUNMAP. */ + unsigned short hb_last_reclaimed; + /* Value of GC_gc_no when block was */ + /* last allocated or swept. May wrap. */ + /* For a free block, this is maintained */ + /* unly for USE_MUNMAP, and indicates */ + /* when the header was allocated, or */ + /* when the size of the block last */ + /* changed. */ + word hb_marks[MARK_BITS_SZ]; + /* Bit i in the array refers to the */ + /* object starting at the ith word (header */ + /* INCLUDED) in the heap block. */ + /* The lsb of word 0 is numbered 0. */ +}; + +/* heap block body */ + +# define DISCARD_WORDS 0 + /* Number of words to be dropped at the beginning of each block */ + /* Must be a multiple of WORDSZ. May reasonably be nonzero */ + /* on machines that don't guarantee longword alignment of */ + /* pointers, so that the number of false hits is minimized. */ + /* 0 and WORDSZ are probably the only reasonable values. */ + +# define BODY_SZ ((HBLKSIZE-WORDS_TO_BYTES(DISCARD_WORDS))/sizeof(word)) + +struct hblk { +# if (DISCARD_WORDS != 0) + word garbage[DISCARD_WORDS]; +# endif + word hb_body[BODY_SZ]; +}; + +# define HDR_WORDS ((word)DISCARD_WORDS) +# define HDR_BYTES ((word)WORDS_TO_BYTES(DISCARD_WORDS)) + +# define OBJ_SZ_TO_BLOCKS(sz) \ + divHBLKSZ(HDR_BYTES + WORDS_TO_BYTES(sz) + HBLKSIZE-1) + /* Size of block (in units of HBLKSIZE) needed to hold objects of */ + /* given sz (in words). */ + +/* Object free list link */ +# define obj_link(p) (*(ptr_t *)(p)) + +/* The type of mark procedures. This really belongs in gc_mark.h. */ +/* But we put it here, so that we can avoid scanning the mark proc */ +/* table. */ +typedef struct ms_entry * (*mark_proc)(/* word * addr, mark_stack_ptr, + mark_stack_limit, env */); +# define LOG_MAX_MARK_PROCS 6 +# define MAX_MARK_PROCS (1 << LOG_MAX_MARK_PROCS) + +/* Root sets. Logically private to mark_rts.c. But we don't want the */ +/* tables scanned, so we put them here. */ +/* MAX_ROOT_SETS is the maximum number of ranges that can be */ +/* registered as static roots. */ +# ifdef LARGE_CONFIG +# define MAX_ROOT_SETS 4096 +# else +# ifdef PCR +# define MAX_ROOT_SETS 1024 +# else +# ifdef MSWIN32 +# define MAX_ROOT_SETS 512 + /* Under NT, we add only written pages, which can result */ + /* in many small root sets. */ +# else +# define MAX_ROOT_SETS 64 +# endif +# endif +# endif + +# define MAX_EXCLUSIONS (MAX_ROOT_SETS/4) +/* Maximum number of segments that can be excluded from root sets. */ + +/* + * Data structure for excluded static roots. + */ +struct exclusion { + ptr_t e_start; + ptr_t e_end; +}; + +/* Data structure for list of root sets. */ +/* We keep a hash table, so that we can filter out duplicate additions. */ +/* Under Win32, we need to do a better job of filtering overlaps, so */ +/* we resort to sequential search, and pay the price. */ +struct roots { + ptr_t r_start; + ptr_t r_end; +# ifndef MSWIN32 + struct roots * r_next; +# endif + GC_bool r_tmp; + /* Delete before registering new dynamic libraries */ +}; + +#ifndef MSWIN32 + /* Size of hash table index to roots. */ +# define LOG_RT_SIZE 6 +# define RT_SIZE (1 << LOG_RT_SIZE) /* Power of 2, may be != MAX_ROOT_SETS */ +#endif + +/* Lists of all heap blocks and free lists */ +/* as well as other random data structures */ +/* that should not be scanned by the */ +/* collector. */ +/* These are grouped together in a struct */ +/* so that they can be easily skipped by the */ +/* GC_mark routine. */ +/* The ordering is weird to make GC_malloc */ +/* faster by keeping the important fields */ +/* sufficiently close together that a */ +/* single load of a base register will do. */ +/* Scalars that could easily appear to */ +/* be pointers are also put here. */ +/* The main fields should precede any */ +/* conditionally included fields, so that */ +/* gc_inl.h will work even if a different set */ +/* of macros is defined when the client is */ +/* compiled. */ + +struct _GC_arrays { + word _heapsize; + word _max_heapsize; + ptr_t _last_heap_addr; + ptr_t _prev_heap_addr; + word _large_free_bytes; + /* Total bytes contained in blocks on large object free */ + /* list. */ + word _words_allocd_before_gc; + /* Number of words allocated before this */ + /* collection cycle. */ + word _words_allocd; + /* Number of words allocated during this collection cycle */ + word _words_wasted; + /* Number of words wasted due to internal fragmentation */ + /* in large objects, or due to dropping blacklisted */ + /* blocks, since last gc. Approximate. */ + word _words_finalized; + /* Approximate number of words in objects (and headers) */ + /* That became ready for finalization in the last */ + /* collection. */ + word _non_gc_bytes_at_gc; + /* Number of explicitly managed bytes of storage */ + /* at last collection. */ + word _mem_freed; + /* Number of explicitly deallocated words of memory */ + /* since last collection. */ + mark_proc _mark_procs[MAX_MARK_PROCS]; + /* Table of user-defined mark procedures. There is */ + /* a small number of these, which can be referenced */ + /* by DS_PROC mark descriptors. See gc_mark.h. */ + ptr_t _objfreelist[MAXOBJSZ+1]; + /* free list for objects */ + ptr_t _aobjfreelist[MAXOBJSZ+1]; + /* free list for atomic objs */ + + ptr_t _uobjfreelist[MAXOBJSZ+1]; + /* uncollectable but traced objs */ + /* objects on this and auobjfreelist */ + /* are always marked, except during */ + /* garbage collections. */ +# ifdef ATOMIC_UNCOLLECTABLE + ptr_t _auobjfreelist[MAXOBJSZ+1]; +# endif + /* uncollectable but traced objs */ + +# ifdef GATHERSTATS + word _composite_in_use; + /* Number of words in accessible composite */ + /* objects. */ + word _atomic_in_use; + /* Number of words in accessible atomic */ + /* objects. */ +# endif +# ifdef USE_MUNMAP + word _unmapped_bytes; +# endif +# ifdef MERGE_SIZES + unsigned _size_map[WORDS_TO_BYTES(MAXOBJSZ+1)]; + /* Number of words to allocate for a given allocation request in */ + /* bytes. */ +# endif + +# ifdef STUBBORN_ALLOC + ptr_t _sobjfreelist[MAXOBJSZ+1]; +# endif + /* free list for immutable objects */ + ptr_t _obj_map[MAXOBJSZ+1]; + /* If not NIL, then a pointer to a map of valid */ + /* object addresses. _obj_map[sz][i] is j if the */ + /* address block_start+i is a valid pointer */ + /* to an object at */ + /* block_start+i&~3 - WORDS_TO_BYTES(j). */ + /* (If ALL_INTERIOR_POINTERS is defined, then */ + /* instead ((short *)(hb_map[sz])[i] is j if */ + /* block_start+WORDS_TO_BYTES(i) is in the */ + /* interior of an object starting at */ + /* block_start+WORDS_TO_BYTES(i-j)). */ + /* It is OBJ_INVALID if */ + /* block_start+WORDS_TO_BYTES(i) is not */ + /* valid as a pointer to an object. */ + /* We assume all values of j <= OBJ_INVALID. */ + /* The zeroth entry corresponds to large objects.*/ +# ifdef ALL_INTERIOR_POINTERS +# define map_entry_type short +# define OBJ_INVALID 0x7fff +# define MAP_ENTRY(map, bytes) \ + (((map_entry_type *)(map))[BYTES_TO_WORDS(bytes)]) +# define MAP_ENTRIES BYTES_TO_WORDS(HBLKSIZE) +# define MAP_SIZE (MAP_ENTRIES * sizeof(map_entry_type)) +# define OFFSET_VALID(displ) TRUE +# define CPP_MAX_OFFSET (HBLKSIZE - HDR_BYTES - 1) +# define MAX_OFFSET ((word)CPP_MAX_OFFSET) +# else +# define map_entry_type char +# define OBJ_INVALID 0x7f +# define MAP_ENTRY(map, bytes) \ + (map)[bytes] +# define MAP_ENTRIES HBLKSIZE +# define MAP_SIZE MAP_ENTRIES +# define CPP_MAX_OFFSET (WORDS_TO_BYTES(OBJ_INVALID) - 1) +# define MAX_OFFSET ((word)CPP_MAX_OFFSET) +# define VALID_OFFSET_SZ \ + (CPP_MAX_OFFSET > WORDS_TO_BYTES(CPP_MAXOBJSZ)? \ + CPP_MAX_OFFSET+1 \ + : WORDS_TO_BYTES(CPP_MAXOBJSZ)+1) + char _valid_offsets[VALID_OFFSET_SZ]; + /* GC_valid_offsets[i] == TRUE ==> i */ + /* is registered as a displacement. */ +# define OFFSET_VALID(displ) GC_valid_offsets[displ] + char _modws_valid_offsets[sizeof(word)]; + /* GC_valid_offsets[i] ==> */ + /* GC_modws_valid_offsets[i%sizeof(word)] */ +# endif +# ifdef STUBBORN_ALLOC + page_hash_table _changed_pages; + /* Stubborn object pages that were changes since last call to */ + /* GC_read_changed. */ + page_hash_table _prev_changed_pages; + /* Stubborn object pages that were changes before last call to */ + /* GC_read_changed. */ +# endif +# if defined(PROC_VDB) || defined(MPROTECT_VDB) + page_hash_table _grungy_pages; /* Pages that were dirty at last */ + /* GC_read_dirty. */ +# endif +# ifdef MPROTECT_VDB + VOLATILE page_hash_table _dirty_pages; + /* Pages dirtied since last GC_read_dirty. */ +# endif +# ifdef PROC_VDB + page_hash_table _written_pages; /* Pages ever dirtied */ +# endif +# ifdef LARGE_CONFIG +# if CPP_WORDSZ > 32 +# define MAX_HEAP_SECTS 4096 /* overflows at roughly 64 GB */ +# else +# define MAX_HEAP_SECTS 768 /* Separately added heap sections. */ +# endif +# else +# define MAX_HEAP_SECTS 256 +# endif + struct HeapSect { + ptr_t hs_start; word hs_bytes; + } _heap_sects[MAX_HEAP_SECTS]; +# ifdef MSWIN32 + ptr_t _heap_bases[MAX_HEAP_SECTS]; + /* Start address of memory regions obtained from kernel. */ +# endif + struct roots _static_roots[MAX_ROOT_SETS]; +# ifndef MSWIN32 + struct roots * _root_index[RT_SIZE]; +# endif + struct exclusion _excl_table[MAX_EXCLUSIONS]; + /* Block header index; see gc_headers.h */ + bottom_index * _all_nils; + bottom_index * _top_index [TOP_SZ]; +#ifdef SAVE_CALL_CHAIN + struct callinfo _last_stack[NFRAMES]; /* Stack at last garbage collection.*/ + /* Useful for debugging mysterious */ + /* object disappearances. */ + /* In the multithreaded case, we */ + /* currently only save the calling */ + /* stack. */ +#endif +}; + +GC_API GC_FAR struct _GC_arrays GC_arrays; + +# define GC_objfreelist GC_arrays._objfreelist +# define GC_aobjfreelist GC_arrays._aobjfreelist +# define GC_uobjfreelist GC_arrays._uobjfreelist +# ifdef ATOMIC_UNCOLLECTABLE +# define GC_auobjfreelist GC_arrays._auobjfreelist +# endif +# define GC_sobjfreelist GC_arrays._sobjfreelist +# define GC_valid_offsets GC_arrays._valid_offsets +# define GC_modws_valid_offsets GC_arrays._modws_valid_offsets +# ifdef STUBBORN_ALLOC +# define GC_changed_pages GC_arrays._changed_pages +# define GC_prev_changed_pages GC_arrays._prev_changed_pages +# endif +# define GC_obj_map GC_arrays._obj_map +# define GC_last_heap_addr GC_arrays._last_heap_addr +# define GC_prev_heap_addr GC_arrays._prev_heap_addr +# define GC_words_allocd GC_arrays._words_allocd +# define GC_words_wasted GC_arrays._words_wasted +# define GC_large_free_bytes GC_arrays._large_free_bytes +# define GC_words_finalized GC_arrays._words_finalized +# define GC_non_gc_bytes_at_gc GC_arrays._non_gc_bytes_at_gc +# define GC_mem_freed GC_arrays._mem_freed +# define GC_mark_procs GC_arrays._mark_procs +# define GC_heapsize GC_arrays._heapsize +# define GC_max_heapsize GC_arrays._max_heapsize +# define GC_words_allocd_before_gc GC_arrays._words_allocd_before_gc +# define GC_heap_sects GC_arrays._heap_sects +# define GC_last_stack GC_arrays._last_stack +# ifdef USE_MUNMAP +# define GC_unmapped_bytes GC_arrays._unmapped_bytes +# endif +# ifdef MSWIN32 +# define GC_heap_bases GC_arrays._heap_bases +# endif +# define GC_static_roots GC_arrays._static_roots +# define GC_root_index GC_arrays._root_index +# define GC_excl_table GC_arrays._excl_table +# define GC_all_nils GC_arrays._all_nils +# define GC_top_index GC_arrays._top_index +# if defined(PROC_VDB) || defined(MPROTECT_VDB) +# define GC_grungy_pages GC_arrays._grungy_pages +# endif +# ifdef MPROTECT_VDB +# define GC_dirty_pages GC_arrays._dirty_pages +# endif +# ifdef PROC_VDB +# define GC_written_pages GC_arrays._written_pages +# endif +# ifdef GATHERSTATS +# define GC_composite_in_use GC_arrays._composite_in_use +# define GC_atomic_in_use GC_arrays._atomic_in_use +# endif +# ifdef MERGE_SIZES +# define GC_size_map GC_arrays._size_map +# endif + +# define beginGC_arrays ((ptr_t)(&GC_arrays)) +# define endGC_arrays (((ptr_t)(&GC_arrays)) + (sizeof GC_arrays)) + +/* Object kinds: */ +# define MAXOBJKINDS 16 + +extern struct obj_kind { + ptr_t *ok_freelist; /* Array of free listheaders for this kind of object */ + /* Point either to GC_arrays or to storage allocated */ + /* with GC_scratch_alloc. */ + struct hblk **ok_reclaim_list; + /* List headers for lists of blocks waiting to be */ + /* swept. */ + word ok_descriptor; /* Descriptor template for objects in this */ + /* block. */ + GC_bool ok_relocate_descr; + /* Add object size in bytes to descriptor */ + /* template to obtain descriptor. Otherwise */ + /* template is used as is. */ + GC_bool ok_init; /* Clear objects before putting them on the free list. */ +} GC_obj_kinds[MAXOBJKINDS]; + +# define endGC_obj_kinds (((ptr_t)(&GC_obj_kinds)) + (sizeof GC_obj_kinds)) + +# define end_gc_area ((ptr_t)endGC_arrays == (ptr_t)(&GC_obj_kinds) ? \ + endGC_obj_kinds : endGC_arrays) + +/* Predefined kinds: */ +# define PTRFREE 0 +# define NORMAL 1 +# define UNCOLLECTABLE 2 +# ifdef ATOMIC_UNCOLLECTABLE +# define AUNCOLLECTABLE 3 +# define STUBBORN 4 +# define IS_UNCOLLECTABLE(k) (((k) & ~1) == UNCOLLECTABLE) +# else +# define STUBBORN 3 +# define IS_UNCOLLECTABLE(k) ((k) == UNCOLLECTABLE) +# endif + +extern int GC_n_kinds; + +GC_API word GC_fo_entries; + +extern word GC_n_heap_sects; /* Number of separately added heap */ + /* sections. */ + +extern word GC_page_size; + +# ifdef MSWIN32 +extern word GC_n_heap_bases; /* See GC_heap_bases. */ +# endif + +extern word GC_total_stack_black_listed; + /* Number of bytes on stack blacklist. */ + +extern word GC_black_list_spacing; + /* Average number of bytes between blacklisted */ + /* blocks. Approximate. */ + /* Counts only blocks that are */ + /* "stack-blacklisted", i.e. that are */ + /* problematic in the interior of an object. */ + +extern char * GC_invalid_map; + /* Pointer to the nowhere valid hblk map */ + /* Blocks pointing to this map are free. */ + +extern struct hblk * GC_hblkfreelist[]; + /* List of completely empty heap blocks */ + /* Linked through hb_next field of */ + /* header structure associated with */ + /* block. */ + +extern GC_bool GC_is_initialized; /* GC_init() has been run. */ + +extern GC_bool GC_objects_are_marked; /* There are marked objects in */ + /* the heap. */ + +#ifndef SMALL_CONFIG + extern GC_bool GC_incremental; + /* Using incremental/generational collection. */ +#else +# define GC_incremental TRUE + /* Hopefully allow optimizer to remove some code. */ +#endif + +extern GC_bool GC_dirty_maintained; + /* Dirty bits are being maintained, */ + /* either for incremental collection, */ + /* or to limit the root set. */ + +extern word GC_root_size; /* Total size of registered root sections */ + +extern GC_bool GC_debugging_started; /* GC_debug_malloc has been called. */ + +extern ptr_t GC_least_plausible_heap_addr; +extern ptr_t GC_greatest_plausible_heap_addr; + /* Bounds on the heap. Guaranteed valid */ + /* Likely to include future heap expansion. */ + +/* Operations */ +# ifndef abs +# define abs(x) ((x) < 0? (-(x)) : (x)) +# endif + + +/* Marks are in a reserved area in */ +/* each heap block. Each word has one mark bit associated */ +/* with it. Only those corresponding to the beginning of an */ +/* object are used. */ + + +/* Mark bit operations */ + +/* + * Retrieve, set, clear the mark bit corresponding + * to the nth word in a given heap block. + * + * (Recall that bit n corresponds to object beginning at word n + * relative to the beginning of the block, including unused words) + */ + +# define mark_bit_from_hdr(hhdr,n) (((hhdr)->hb_marks[divWORDSZ(n)] \ + >> (modWORDSZ(n))) & (word)1) +# define set_mark_bit_from_hdr(hhdr,n) (hhdr)->hb_marks[divWORDSZ(n)] \ + |= (word)1 << modWORDSZ(n) + +# define clear_mark_bit_from_hdr(hhdr,n) (hhdr)->hb_marks[divWORDSZ(n)] \ + &= ~((word)1 << modWORDSZ(n)) + +/* Important internal collector routines */ + +ptr_t GC_approx_sp(); + +GC_bool GC_should_collect(); +#ifdef PRESERVE_LAST + GC_bool GC_in_last_heap_sect(/* ptr_t */); + /* In last added heap section? If so, avoid breaking up. */ +#endif +void GC_apply_to_all_blocks(/*fn, client_data*/); + /* Invoke fn(hbp, client_data) for each */ + /* allocated heap block. */ +struct hblk * GC_next_used_block(/* struct hblk * h */); + /* Return first in-use block >= h */ +struct hblk * GC_prev_block(/* struct hblk * h */); + /* Return last block <= h. Returned block */ + /* is managed by GC, but may or may not be in */ + /* use. */ +void GC_mark_init(); +void GC_clear_marks(); /* Clear mark bits for all heap objects. */ +void GC_invalidate_mark_state(); /* Tell the marker that marked */ + /* objects may point to unmarked */ + /* ones, and roots may point to */ + /* unmarked objects. */ + /* Reset mark stack. */ +void GC_mark_from_mark_stack(); /* Mark from everything on the mark stack. */ + /* Return after about one pages worth of */ + /* work. */ +GC_bool GC_mark_stack_empty(); +GC_bool GC_mark_some(/* cold_gc_frame */); + /* Perform about one pages worth of marking */ + /* work of whatever kind is needed. Returns */ + /* quickly if no collection is in progress. */ + /* Return TRUE if mark phase finished. */ +void GC_initiate_gc(); /* initiate collection. */ + /* If the mark state is invalid, this */ + /* becomes full colleection. Otherwise */ + /* it's partial. */ +void GC_push_all(/*b,t*/); /* Push everything in a range */ + /* onto mark stack. */ +void GC_push_dirty(/*b,t*/); /* Push all possibly changed */ + /* subintervals of [b,t) onto */ + /* mark stack. */ +#ifndef SMALL_CONFIG + void GC_push_conditional(/* ptr_t b, ptr_t t, GC_bool all*/); +#else +# define GC_push_conditional(b, t, all) GC_push_all(b, t) +#endif + /* Do either of the above, depending */ + /* on the third arg. */ +void GC_push_all_stack(/*b,t*/); /* As above, but consider */ + /* interior pointers as valid */ +void GC_push_all_eager(/*b,t*/); /* Same as GC_push_all_stack, but */ + /* ensures that stack is scanned */ + /* immediately, not just scheduled */ + /* for scanning. */ +#ifndef THREADS + void GC_push_all_stack_partially_eager(/* bottom, top, cold_gc_frame */); + /* Similar to GC_push_all_eager, but only the */ + /* part hotter than cold_gc_frame is scanned */ + /* immediately. Needed to endure that callee- */ + /* save registers are not missed. */ +#else + /* In the threads case, we push part of the current thread stack */ + /* with GC_push_all_eager when we push the registers. This gets the */ + /* callee-save registers that may disappear. The remainder of the */ + /* stacks are scheduled for scanning in *GC_push_other_roots, which */ + /* is thread-package-specific. */ +#endif +void GC_push_current_stack(/* ptr_t cold_gc_frame */); + /* Push enough of the current stack eagerly to */ + /* ensure that callee-save registers saved in */ + /* GC frames are scanned. */ + /* In the non-threads case, schedule entire */ + /* stack for scanning. */ +void GC_push_roots(/* GC_bool all, ptr_t cold_gc_frame */); + /* Push all or dirty roots. */ +extern void (*GC_push_other_roots)(); + /* Push system or application specific roots */ + /* onto the mark stack. In some environments */ + /* (e.g. threads environments) this is */ + /* predfined to be non-zero. A client supplied */ + /* replacement should also call the original */ + /* function. */ +extern void (*GC_start_call_back)(/* void */); + /* Called at start of full collections. */ + /* Not called if 0. Called with allocation */ + /* lock held. */ + /* 0 by default. */ +void GC_push_regs(); /* Push register contents onto mark stack. */ +void GC_remark(); /* Mark from all marked objects. Used */ + /* only if we had to drop something. */ +# if defined(MSWIN32) + void __cdecl GC_push_one(); +# else + void GC_push_one(/*p*/); /* If p points to an object, mark it */ + /* and push contents on the mark stack */ +# endif +void GC_push_one_checked(/*p*/); /* Ditto, omits plausibility test */ +void GC_push_marked(/* struct hblk h, hdr * hhdr */); + /* Push contents of all marked objects in h onto */ + /* mark stack. */ +#ifdef SMALL_CONFIG +# define GC_push_next_marked_dirty(h) GC_push_next_marked(h) +#else + struct hblk * GC_push_next_marked_dirty(/* h */); + /* Invoke GC_push_marked on next dirty block above h. */ + /* Return a pointer just past the end of this block. */ +#endif /* !SMALL_CONFIG */ +struct hblk * GC_push_next_marked(/* h */); + /* Ditto, but also mark from clean pages. */ +struct hblk * GC_push_next_marked_uncollectable(/* h */); + /* Ditto, but mark only from uncollectable pages. */ +GC_bool GC_stopped_mark(); /* Stop world and mark from all roots */ + /* and rescuers. */ +void GC_clear_hdr_marks(/* hhdr */); /* Clear the mark bits in a header */ +void GC_set_hdr_marks(/* hhdr */); /* Set the mark bits in a header */ +void GC_add_roots_inner(); +GC_bool GC_is_static_root(/* ptr_t p */); + /* Is the address p in one of the registered static */ + /* root sections? */ +void GC_register_dynamic_libraries(); + /* Add dynamic library data sections to the root set. */ + +/* Machine dependent startup routines */ +ptr_t GC_get_stack_base(); +void GC_register_data_segments(); + +/* Black listing: */ +void GC_bl_init(); +# ifndef ALL_INTERIOR_POINTERS + void GC_add_to_black_list_normal(/* bits, maybe source */); + /* Register bits as a possible future false */ + /* reference from the heap or static data */ +# ifdef PRINT_BLACK_LIST +# define GC_ADD_TO_BLACK_LIST_NORMAL(bits, source) \ + GC_add_to_black_list_normal(bits, source) +# else +# define GC_ADD_TO_BLACK_LIST_NORMAL(bits, source) \ + GC_add_to_black_list_normal(bits) +# endif +# else +# ifdef PRINT_BLACK_LIST +# define GC_ADD_TO_BLACK_LIST_NORMAL(bits, source) \ + GC_add_to_black_list_stack(bits, source) +# else +# define GC_ADD_TO_BLACK_LIST_NORMAL(bits, source) \ + GC_add_to_black_list_stack(bits) +# endif +# endif + +void GC_add_to_black_list_stack(/* bits, maybe source */); +struct hblk * GC_is_black_listed(/* h, len */); + /* If there are likely to be false references */ + /* to a block starting at h of the indicated */ + /* length, then return the next plausible */ + /* starting location for h that might avoid */ + /* these false references. */ +void GC_promote_black_lists(); + /* Declare an end to a black listing phase. */ +void GC_unpromote_black_lists(); + /* Approximately undo the effect of the above. */ + /* This actually loses some information, but */ + /* only in a reasonably safe way. */ +word GC_number_stack_black_listed(/*struct hblk *start, struct hblk *endp1 */); + /* Return the number of (stack) blacklisted */ + /* blocks in the range for statistical */ + /* purposes. */ + +ptr_t GC_scratch_alloc(/*bytes*/); + /* GC internal memory allocation for */ + /* small objects. Deallocation is not */ + /* possible. */ + +/* Heap block layout maps: */ +void GC_invalidate_map(/* hdr */); + /* Remove the object map associated */ + /* with the block. This identifies */ + /* the block as invalid to the mark */ + /* routines. */ +GC_bool GC_add_map_entry(/*sz*/); + /* Add a heap block map for objects of */ + /* size sz to obj_map. */ + /* Return FALSE on failure. */ +void GC_register_displacement_inner(/*offset*/); + /* Version of GC_register_displacement */ + /* that assumes lock is already held */ + /* and signals are already disabled. */ + +/* hblk allocation: */ +void GC_new_hblk(/*size_in_words, kind*/); + /* Allocate a new heap block, and build */ + /* a free list in it. */ +struct hblk * GC_allochblk(/*size_in_words, kind*/); + /* Allocate a heap block, clear it if */ + /* for composite objects, inform */ + /* the marker that block is valid */ + /* for objects of indicated size. */ + /* sz < 0 ==> atomic. */ +void GC_freehblk(); /* Deallocate a heap block and mark it */ + /* as invalid. */ + +/* Misc GC: */ +void GC_init_inner(); +GC_bool GC_expand_hp_inner(); +void GC_start_reclaim(/*abort_if_found*/); + /* Restore unmarked objects to free */ + /* lists, or (if abort_if_found is */ + /* TRUE) report them. */ + /* Sweeping of small object pages is */ + /* largely deferred. */ +void GC_continue_reclaim(/*size, kind*/); + /* Sweep pages of the given size and */ + /* kind, as long as possible, and */ + /* as long as the corr. free list is */ + /* empty. */ +void GC_reclaim_or_delete_all(); + /* Arrange for all reclaim lists to be */ + /* empty. Judiciously choose between */ + /* sweeping and discarding each page. */ +GC_bool GC_reclaim_all(/* GC_stop_func f*/); + /* Reclaim all blocks. Abort (in a */ + /* consistent state) if f returns TRUE. */ +GC_bool GC_block_empty(/* hhdr */); /* Block completely unmarked? */ +GC_bool GC_never_stop_func(); /* Returns FALSE. */ +GC_bool GC_try_to_collect_inner(/* GC_stop_func f */); + /* Collect; caller must have acquired */ + /* lock and disabled signals. */ + /* Collection is aborted if f returns */ + /* TRUE. Returns TRUE if it completes */ + /* successfully. */ +# define GC_gcollect_inner() \ + (void) GC_try_to_collect_inner(GC_never_stop_func) +void GC_finish_collection(); /* Finish collection. Mark bits are */ + /* consistent and lock is still held. */ +GC_bool GC_collect_or_expand(/* needed_blocks */); + /* Collect or expand heap in an attempt */ + /* make the indicated number of free */ + /* blocks available. Should be called */ + /* until the blocks are available or */ + /* until it fails by returning FALSE. */ +GC_API void GC_init(); /* Initialize collector. */ +void GC_collect_a_little_inner(/* int n */); + /* Do n units worth of garbage */ + /* collection work, if appropriate. */ + /* A unit is an amount appropriate for */ + /* HBLKSIZE bytes of allocation. */ +ptr_t GC_generic_malloc(/* bytes, kind */); + /* Allocate an object of the given */ + /* kind. By default, there are only */ + /* a few kinds: composite(pointerfree), */ + /* atomic, uncollectable, etc. */ + /* We claim it's possible for clever */ + /* client code that understands GC */ + /* internals to add more, e.g. to */ + /* communicate object layout info */ + /* to the collector. */ +ptr_t GC_generic_malloc_ignore_off_page(/* bytes, kind */); + /* As above, but pointers past the */ + /* first page of the resulting object */ + /* are ignored. */ +ptr_t GC_generic_malloc_inner(/* bytes, kind */); + /* Ditto, but I already hold lock, etc. */ +ptr_t GC_generic_malloc_words_small GC_PROTO((size_t words, int kind)); + /* As above, but size in units of words */ + /* Bypasses MERGE_SIZES. Assumes */ + /* words <= MAXOBJSZ. */ +ptr_t GC_generic_malloc_inner_ignore_off_page(/* bytes, kind */); + /* Allocate an object, where */ + /* the client guarantees that there */ + /* will always be a pointer to the */ + /* beginning of the object while the */ + /* object is live. */ +ptr_t GC_allocobj(/* sz_inn_words, kind */); + /* Make the indicated */ + /* free list nonempty, and return its */ + /* head. */ + +void GC_init_headers(); +GC_bool GC_install_header(/*h*/); + /* Install a header for block h. */ + /* Return FALSE on failure. */ +GC_bool GC_install_counts(/*h, sz*/); + /* Set up forwarding counts for block */ + /* h of size sz. */ + /* Return FALSE on failure. */ +void GC_remove_header(/*h*/); + /* Remove the header for block h. */ +void GC_remove_counts(/*h, sz*/); + /* Remove forwarding counts for h. */ +hdr * GC_find_header(/*p*/); /* Debugging only. */ + +void GC_finalize(); /* Perform all indicated finalization actions */ + /* on unmarked objects. */ + /* Unreachable finalizable objects are enqueued */ + /* for processing by GC_invoke_finalizers. */ + /* Invoked with lock. */ + +void GC_add_to_heap(/*p, bytes*/); + /* Add a HBLKSIZE aligned chunk to the heap. */ + +void GC_print_obj(/* ptr_t p */); + /* P points to somewhere inside an object with */ + /* debugging info. Print a human readable */ + /* description of the object to stderr. */ +extern void (*GC_check_heap)(); + /* Check that all objects in the heap with */ + /* debugging info are intact. Print */ + /* descriptions of any that are not. */ +extern void (*GC_print_heap_obj)(/* ptr_t p */); + /* If possible print s followed by a more */ + /* detailed description of the object */ + /* referred to by p. */ + +/* Memory unmapping: */ +#ifdef USE_MUNMAP + void GC_unmap_old(void); + void GC_merge_unmapped(void); + void GC_unmap(ptr_t start, word bytes); + void GC_remap(ptr_t start, word bytes); + void GC_unmap_gap(ptr_t start1, word bytes1, ptr_t start2, word bytes2); +#endif + +/* Virtual dirty bit implementation: */ +/* Each implementation exports the following: */ +void GC_read_dirty(); /* Retrieve dirty bits. */ +GC_bool GC_page_was_dirty(/* struct hblk * h */); + /* Read retrieved dirty bits. */ +GC_bool GC_page_was_ever_dirty(/* struct hblk * h */); + /* Could the page contain valid heap pointers? */ +void GC_is_fresh(/* struct hblk * h, word number_of_blocks */); + /* Assert the region currently contains no */ + /* valid pointers. */ +void GC_write_hint(/* struct hblk * h */); + /* h is about to be written. */ +void GC_dirty_init(); + +/* Slow/general mark bit manipulation: */ +GC_API GC_bool GC_is_marked(); +void GC_clear_mark_bit(); +void GC_set_mark_bit(); + +/* Stubborn objects: */ +void GC_read_changed(); /* Analogous to GC_read_dirty */ +GC_bool GC_page_was_changed(/* h */); /* Analogous to GC_page_was_dirty */ +void GC_clean_changing_list(); /* Collect obsolete changing list entries */ +void GC_stubborn_init(); + +/* Debugging print routines: */ +void GC_print_block_list(); +void GC_print_hblkfreelist(); +void GC_print_heap_sects(); +void GC_print_static_roots(); +void GC_dump(); + +#ifdef KEEP_BACK_PTRS + void GC_store_back_pointer(ptr_t source, ptr_t dest); + void GC_marked_for_finalization(ptr_t dest); +# define GC_STORE_BACK_PTR(source, dest) GC_store_back_pointer(source, dest) +# define GC_MARKED_FOR_FINALIZATION(dest) GC_marked_for_finalization(dest) +#else +# define GC_STORE_BACK_PTR(source, dest) +# define GC_MARKED_FOR_FINALIZATION(dest) +#endif + +/* Make arguments appear live to compiler */ +# ifdef __WATCOMC__ + void GC_noop(void*, ...); +# else + GC_API void GC_noop(); +# endif + +void GC_noop1(/* word arg */); + +/* Logging and diagnostic output: */ +GC_API void GC_printf GC_PROTO((char * format, long, long, long, long, long, long)); + /* A version of printf that doesn't allocate, */ + /* is restricted to long arguments, and */ + /* (unfortunately) doesn't use varargs for */ + /* portability. Restricted to 6 args and */ + /* 1K total output length. */ + /* (We use sprintf. Hopefully that doesn't */ + /* allocate for long arguments.) */ +# define GC_printf0(f) GC_printf(f, 0l, 0l, 0l, 0l, 0l, 0l) +# define GC_printf1(f,a) GC_printf(f, (long)a, 0l, 0l, 0l, 0l, 0l) +# define GC_printf2(f,a,b) GC_printf(f, (long)a, (long)b, 0l, 0l, 0l, 0l) +# define GC_printf3(f,a,b,c) GC_printf(f, (long)a, (long)b, (long)c, 0l, 0l, 0l) +# define GC_printf4(f,a,b,c,d) GC_printf(f, (long)a, (long)b, (long)c, \ + (long)d, 0l, 0l) +# define GC_printf5(f,a,b,c,d,e) GC_printf(f, (long)a, (long)b, (long)c, \ + (long)d, (long)e, 0l) +# define GC_printf6(f,a,b,c,d,e,g) GC_printf(f, (long)a, (long)b, (long)c, \ + (long)d, (long)e, (long)g) + +void GC_err_printf(/* format, a, b, c, d, e, f */); +# define GC_err_printf0(f) GC_err_puts(f) +# define GC_err_printf1(f,a) GC_err_printf(f, (long)a, 0l, 0l, 0l, 0l, 0l) +# define GC_err_printf2(f,a,b) GC_err_printf(f, (long)a, (long)b, 0l, 0l, 0l, 0l) +# define GC_err_printf3(f,a,b,c) GC_err_printf(f, (long)a, (long)b, (long)c, \ + 0l, 0l, 0l) +# define GC_err_printf4(f,a,b,c,d) GC_err_printf(f, (long)a, (long)b, \ + (long)c, (long)d, 0l, 0l) +# define GC_err_printf5(f,a,b,c,d,e) GC_err_printf(f, (long)a, (long)b, \ + (long)c, (long)d, \ + (long)e, 0l) +# define GC_err_printf6(f,a,b,c,d,e,g) GC_err_printf(f, (long)a, (long)b, \ + (long)c, (long)d, \ + (long)e, (long)g) + /* Ditto, writes to stderr. */ + +void GC_err_puts(/* char *s */); + /* Write s to stderr, don't buffer, don't add */ + /* newlines, don't ... */ + + +# ifdef GC_ASSERTIONS +# define GC_ASSERT(expr) if(!(expr)) {\ + GC_err_printf2("Assertion failure: %s:%ld\n", \ + __FILE__, (unsigned long)__LINE__); \ + ABORT("assertion failure"); } +# else +# define GC_ASSERT(expr) +# endif + +# endif /* GC_PRIVATE_H */ diff --git a/gc/include/private/gcconfig.h b/gc/include/private/gcconfig.h new file mode 100644 index 0000000..c9017d3 --- /dev/null +++ b/gc/include/private/gcconfig.h @@ -0,0 +1,1099 @@ +/* + * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers + * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved. + * Copyright (c) 1996 by Silicon Graphics. All rights reserved. + * + * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED + * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + * + * Permission is hereby granted to use or copy this program + * for any purpose, provided the above notices are retained on all copies. + * Permission to modify the code and to distribute modified code is granted, + * provided the above notices are retained, and a notice that the code was + * modified is included with the above copyright notice. + */ + +#ifndef CONFIG_H + +# define CONFIG_H + +/* Machine dependent parameters. Some tuning parameters can be found */ +/* near the top of gc_private.h. */ + +/* Machine specific parts contributed by various people. See README file. */ + +/* First a unified test for Linux: */ +# if defined(linux) || defined(__linux__) +# define LINUX +# endif + +/* Determine the machine type: */ +# if defined(sun) && defined(mc68000) +# define M68K +# define SUNOS4 +# define mach_type_known +# endif +# if defined(hp9000s300) +# define M68K +# define HP +# define mach_type_known +# endif +# if defined(__OpenBSD__) && defined(m68k) +# define M68K +# define OPENBSD +# define mach_type_known +# endif +# if defined(__OpenBSD__) && defined(__sparc__) +# define SPARC +# define OPENBSD +# define mach_type_known +# endif +# if defined(__NetBSD__) && defined(m68k) +# define M68K +# define NETBSD +# define mach_type_known +# endif +# if defined(vax) +# define VAX +# ifdef ultrix +# define ULTRIX +# else +# define BSD +# endif +# define mach_type_known +# endif +# if defined(mips) || defined(__mips) +# define MIPS +# if defined(ultrix) || defined(__ultrix) || defined(__NetBSD__) +# define ULTRIX +# else +# if defined(_SYSTYPE_SVR4) || defined(SYSTYPE_SVR4) || defined(__SYSTYPE_SVR4__) +# define IRIX5 /* or IRIX 6.X */ +# else +# define RISCOS /* or IRIX 4.X */ +# endif +# endif +# define mach_type_known +# endif +# if defined(sequent) && defined(i386) +# define I386 +# define SEQUENT +# define mach_type_known +# endif +# if defined(sun) && defined(i386) +# define I386 +# define SUNOS5 +# define mach_type_known +# endif +# if (defined(__OS2__) || defined(__EMX__)) && defined(__32BIT__) +# define I386 +# define OS2 +# define mach_type_known +# endif +# if defined(ibm032) +# define RT +# define mach_type_known +# endif +# if defined(sun) && (defined(sparc) || defined(__sparc)) +# define SPARC + /* Test for SunOS 5.x */ +# include <errno.h> +# ifdef ECHRNG +# define SUNOS5 +# else +# define SUNOS4 +# endif +# define mach_type_known +# endif +# if defined(sparc) && defined(unix) && !defined(sun) && !defined(linux) \ + && !defined(__OpenBSD__) +# define SPARC +# define DRSNX +# define mach_type_known +# endif +# if defined(_IBMR2) +# define RS6000 +# define mach_type_known +# endif +# if defined(_M_XENIX) && defined(_M_SYSV) && defined(_M_I386) + /* The above test may need refinement */ +# define I386 +# if defined(_SCO_ELF) +# define SCO_ELF +# else +# define SCO +# endif +# define mach_type_known +# endif +# if defined(_AUX_SOURCE) +# define M68K +# define SYSV +# define mach_type_known +# endif +# if defined(_PA_RISC1_0) || defined(_PA_RISC1_1) \ + || defined(hppa) || defined(__hppa__) +# define HP_PA +# define mach_type_known +# endif +# if defined(LINUX) && (defined(i386) || defined(__i386__)) +# define I386 +# define mach_type_known +# endif +# if defined(LINUX) && defined(powerpc) +# define POWERPC +# define mach_type_known +# endif +# if defined(LINUX) && defined(__mc68000__) +# define M68K +# define mach_type_known +# endif +# if defined(LINUX) && defined(sparc) +# define SPARC +# define mach_type_known +# endif +# if defined(__alpha) || defined(__alpha__) +# define ALPHA +# if !defined(LINUX) +# define OSF1 /* a.k.a Digital Unix */ +# endif +# define mach_type_known +# endif +# if defined(_AMIGA) && !defined(AMIGA) +# define AMIGA +# endif +# ifdef AMIGA +# define M68K +# define mach_type_known +# endif +# if defined(THINK_C) || defined(__MWERKS__) && !defined(__powerc) +# define M68K +# define MACOS +# define mach_type_known +# endif +# if defined(__MWERKS__) && defined(__powerc) +# define POWERPC +# define MACOS +# define mach_type_known +# endif +# if defined(macosx) +# define MACOSX +# define POWERPC +# define mach_type_known +# endif +# if defined(NeXT) && defined(mc68000) +# define M68K +# define NEXT +# define mach_type_known +# endif +# if defined(NeXT) && defined(i386) +# define I386 +# define NEXT +# define mach_type_known +# endif +# if defined(__OpenBSD__) && defined(i386) +# define I386 +# define OPENBSD +# define mach_type_known +# endif +# if defined(__FreeBSD__) && defined(i386) +# define I386 +# define FREEBSD +# define mach_type_known +# endif +# if defined(__NetBSD__) && defined(i386) +# define I386 +# define NETBSD +# define mach_type_known +# endif +# if defined(bsdi) && defined(i386) +# define I386 +# define BSDI +# define mach_type_known +# endif +# if !defined(mach_type_known) && defined(__386BSD__) +# define I386 +# define THREE86BSD +# define mach_type_known +# endif +# if defined(_CX_UX) && defined(_M88K) +# define M88K +# define CX_UX +# define mach_type_known +# endif +# if defined(DGUX) +# define M88K + /* DGUX defined */ +# define mach_type_known +# endif +# if (defined(_MSDOS) || defined(_MSC_VER)) && (_M_IX86 >= 300) \ + || defined(_WIN32) && !defined(__CYGWIN32__) && !defined(__CYGWIN__) +# define I386 +# define MSWIN32 /* or Win32s */ +# define mach_type_known +# endif +# if defined(__DJGPP__) +# define I386 +# ifndef DJGPP +# define DJGPP /* MSDOS running the DJGPP port of GCC */ +# endif +# define mach_type_known +# endif +# if defined(__CYGWIN32__) || defined(__CYGWIN__) +# define I386 +# define CYGWIN32 +# define mach_type_known +# endif +# if defined(__BORLANDC__) +# define I386 +# define MSWIN32 +# define mach_type_known +# endif +# if defined(_UTS) && !defined(mach_type_known) +# define S370 +# define UTS4 +# define mach_type_known +# endif +/* Ivan Demakov */ +# if defined(__WATCOMC__) && defined(__386__) +# define I386 +# if !defined(OS2) && !defined(MSWIN32) && !defined(DOS4GW) +# if defined(__OS2__) +# define OS2 +# else +# if defined(__WINDOWS_386__) || defined(__NT__) +# define MSWIN32 +# else +# define DOS4GW +# endif +# endif +# endif +# define mach_type_known +# endif + +/* Feel free to add more clauses here */ + +/* Or manually define the machine type here. A machine type is */ +/* characterized by the architecture. Some */ +/* machine types are further subdivided by OS. */ +/* the macros ULTRIX, RISCOS, and BSD to distinguish. */ +/* Note that SGI IRIX is treated identically to RISCOS. */ +/* SYSV on an M68K actually means A/UX. */ +/* The distinction in these cases is usually the stack starting address */ +# ifndef mach_type_known + --> unknown machine type +# endif + /* Mapping is: M68K ==> Motorola 680X0 */ + /* (SUNOS4,HP,NEXT, and SYSV (A/UX), */ + /* MACOS and AMIGA variants) */ + /* I386 ==> Intel 386 */ + /* (SEQUENT, OS2, SCO, LINUX, NETBSD, */ + /* FREEBSD, THREE86BSD, MSWIN32, */ + /* BSDI,SUNOS5, NEXT, other variants) */ + /* NS32K ==> Encore Multimax */ + /* MIPS ==> R2000 or R3000 */ + /* (RISCOS, ULTRIX variants) */ + /* VAX ==> DEC VAX */ + /* (BSD, ULTRIX variants) */ + /* RS6000 ==> IBM RS/6000 AIX3.X */ + /* RT ==> IBM PC/RT */ + /* HP_PA ==> HP9000/700 & /800 */ + /* HP/UX */ + /* SPARC ==> SPARC under SunOS */ + /* (SUNOS4, SUNOS5, */ + /* DRSNX variants) */ + /* ALPHA ==> DEC Alpha */ + /* (OSF1 and LINUX variants) */ + /* M88K ==> Motorola 88XX0 */ + /* (CX_UX and DGUX) */ + /* S370 ==> 370-like machine */ + /* running Amdahl UTS4 */ + + +/* + * For each architecture and OS, the following need to be defined: + * + * CPP_WORD_SZ is a simple integer constant representing the word size. + * in bits. We assume byte addressibility, where a byte has 8 bits. + * We also assume CPP_WORD_SZ is either 32 or 64. + * (We care about the length of pointers, not hardware + * bus widths. Thus a 64 bit processor with a C compiler that uses + * 32 bit pointers should use CPP_WORD_SZ of 32, not 64. Default is 32.) + * + * MACH_TYPE is a string representation of the machine type. + * OS_TYPE is analogous for the OS. + * + * ALIGNMENT is the largest N, such that + * all pointer are guaranteed to be aligned on N byte boundaries. + * defining it to be 1 will always work, but perform poorly. + * + * DATASTART is the beginning of the data segment. + * On UNIX systems, the collector will scan the area between DATASTART + * and DATAEND for root pointers. + * + * DATAEND, if not &end. + * + * ALIGN_DOUBLE of GC_malloc should return blocks aligned to twice + * the pointer size. + * + * STACKBOTTOM is the cool end of the stack, which is usually the + * highest address in the stack. + * Under PCR or OS/2, we have other ways of finding thread stacks. + * For each machine, the following should: + * 1) define STACK_GROWS_UP if the stack grows toward higher addresses, and + * 2) define exactly one of + * STACKBOTTOM (should be defined to be an expression) + * HEURISTIC1 + * HEURISTIC2 + * If either of the last two macros are defined, then STACKBOTTOM is computed + * during collector startup using one of the following two heuristics: + * HEURISTIC1: Take an address inside GC_init's frame, and round it up to + * the next multiple of STACK_GRAN. + * HEURISTIC2: Take an address inside GC_init's frame, increment it repeatedly + * in small steps (decrement if STACK_GROWS_UP), and read the value + * at each location. Remember the value when the first + * Segmentation violation or Bus error is signalled. Round that + * to the nearest plausible page boundary, and use that instead + * of STACKBOTTOM. + * + * If no expression for STACKBOTTOM can be found, and neither of the above + * heuristics are usable, the collector can still be used with all of the above + * undefined, provided one of the following is done: + * 1) GC_mark_roots can be changed to somehow mark from the correct stack(s) + * without reference to STACKBOTTOM. This is appropriate for use in + * conjunction with thread packages, since there will be multiple stacks. + * (Allocating thread stacks in the heap, and treating them as ordinary + * heap data objects is also possible as a last resort. However, this is + * likely to introduce significant amounts of excess storage retention + * unless the dead parts of the thread stacks are periodically cleared.) + * 2) Client code may set GC_stackbottom before calling any GC_ routines. + * If the author of the client code controls the main program, this is + * easily accomplished by introducing a new main program, setting + * GC_stackbottom to the address of a local variable, and then calling + * the original main program. The new main program would read something + * like: + * + * # include "gc_private.h" + * + * main(argc, argv, envp) + * int argc; + * char **argv, **envp; + * { + * int dummy; + * + * GC_stackbottom = (ptr_t)(&dummy); + * return(real_main(argc, argv, envp)); + * } + * + * + * Each architecture may also define the style of virtual dirty bit + * implementation to be used: + * MPROTECT_VDB: Write protect the heap and catch faults. + * PROC_VDB: Use the SVR4 /proc primitives to read dirty bits. + * + * An architecture may define DYNAMIC_LOADING if dynamic_load.c + * defined GC_register_dynamic_libraries() for the architecture. + */ + + +# define STACK_GRAN 0x1000000 +# ifdef M68K +# define MACH_TYPE "M68K" +# define ALIGNMENT 2 +# ifdef OPENBSD +# define OS_TYPE "OPENBSD" +# define HEURISTIC2 + extern char etext; +# define DATASTART ((ptr_t)(&etext)) +# endif +# ifdef NETBSD +# define OS_TYPE "NETBSD" +# define HEURISTIC2 + extern char etext; +# define DATASTART ((ptr_t)(&etext)) +# endif +# ifdef LINUX +# define OS_TYPE "LINUX" +# define STACKBOTTOM ((ptr_t)0xf0000000) +# define MPROTECT_VDB +# ifdef __ELF__ +# define DYNAMIC_LOADING + extern char **__environ; +# define DATASTART ((ptr_t)(&__environ)) + /* hideous kludge: __environ is the first */ + /* word in crt0.o, and delimits the start */ + /* of the data segment, no matter which */ + /* ld options were passed through. */ + /* We could use _etext instead, but that */ + /* would include .rodata, which may */ + /* contain large read-only data tables */ + /* that we'd rather not scan. */ + extern int _end; +# define DATAEND (&_end) +# else + extern int etext; +# define DATASTART ((ptr_t)((((word) (&etext)) + 0xfff) & ~0xfff)) +# endif +# endif +# ifdef SUNOS4 +# define OS_TYPE "SUNOS4" + extern char etext; +# define DATASTART ((ptr_t)((((word) (&etext)) + 0x1ffff) & ~0x1ffff)) +# define HEURISTIC1 /* differs */ +# define DYNAMIC_LOADING +# endif +# ifdef HP +# define OS_TYPE "HP" + extern char etext; +# define DATASTART ((ptr_t)((((word) (&etext)) + 0xfff) & ~0xfff)) +# define STACKBOTTOM ((ptr_t) 0xffeffffc) + /* empirically determined. seems to work. */ +# include <unistd.h> +# define GETPAGESIZE() sysconf(_SC_PAGE_SIZE) +# endif +# ifdef SYSV +# define OS_TYPE "SYSV" + extern etext; +# define DATASTART ((ptr_t)((((word) (&etext)) + 0x3fffff) \ + & ~0x3fffff) \ + +((word)&etext & 0x1fff)) + /* This only works for shared-text binaries with magic number 0413. + The other sorts of SysV binaries put the data at the end of the text, + in which case the default of &etext would work. Unfortunately, + handling both would require having the magic-number available. + -- Parag + */ +# define STACKBOTTOM ((ptr_t)0xFFFFFFFE) + /* The stack starts at the top of memory, but */ + /* 0x0 cannot be used as setjump_test complains */ + /* that the stack direction is incorrect. Two */ + /* bytes down from 0x0 should be safe enough. */ + /* --Parag */ +# include <sys/mmu.h> +# define GETPAGESIZE() PAGESIZE /* Is this still right? */ +# endif +# ifdef AMIGA +# define OS_TYPE "AMIGA" + /* STACKBOTTOM and DATASTART handled specially */ + /* in os_dep.c */ +# define DATAEND /* not needed */ +# define GETPAGESIZE() 4096 +# endif +# ifdef MACOS +# ifndef __LOWMEM__ +# include <LowMem.h> +# endif +# define OS_TYPE "MACOS" + /* see os_dep.c for details of global data segments. */ +# define STACKBOTTOM ((ptr_t) LMGetCurStackBase()) +# define DATAEND /* not needed */ +# define GETPAGESIZE() 4096 +# endif +# ifdef NEXT +# define OS_TYPE "NEXT" +# define DATASTART ((ptr_t) get_etext()) +# define STACKBOTTOM ((ptr_t) 0x4000000) +# define DATAEND /* not needed */ +# endif +# endif + +# ifdef POWERPC +# define MACH_TYPE "POWERPC" +# ifdef MACOS +# define ALIGNMENT 2 /* Still necessary? Could it be 4? */ +# ifndef __LOWMEM__ +# include <LowMem.h> +# endif +# define OS_TYPE "MACOS" + /* see os_dep.c for details of global data segments. */ +# define STACKBOTTOM ((ptr_t) LMGetCurStackBase()) +# define DATAEND /* not needed */ +# endif +# ifdef LINUX +# define ALIGNMENT 4 /* Guess. Can someone verify? */ + /* This was 2, but that didn't sound right. */ +# define OS_TYPE "LINUX" +# define HEURISTIC1 +# undef STACK_GRAN +# define STACK_GRAN 0x10000000 + /* Stack usually starts at 0x80000000 */ +# define DATASTART GC_data_start + extern int _end; +# define DATAEND (&_end) +# endif +# ifdef MACOSX +# define ALIGNMENT 4 +# define OS_TYPE "MACOSX" +# define DATASTART ((ptr_t) get_etext()) +# define STACKBOTTOM ((ptr_t) 0xc0000000) +# define DATAEND /* not needed */ +# endif +# endif + +# ifdef VAX +# define MACH_TYPE "VAX" +# define ALIGNMENT 4 /* Pointers are longword aligned by 4.2 C compiler */ + extern char etext; +# define DATASTART ((ptr_t)(&etext)) +# ifdef BSD +# define OS_TYPE "BSD" +# define HEURISTIC1 + /* HEURISTIC2 may be OK, but it's hard to test. */ +# endif +# ifdef ULTRIX +# define OS_TYPE "ULTRIX" +# define STACKBOTTOM ((ptr_t) 0x7fffc800) +# endif +# endif + +# ifdef RT +# define MACH_TYPE "RT" +# define ALIGNMENT 4 +# define DATASTART ((ptr_t) 0x10000000) +# define STACKBOTTOM ((ptr_t) 0x1fffd800) +# endif + +# ifdef SPARC +# define MACH_TYPE "SPARC" +# define ALIGNMENT 4 /* Required by hardware */ +# define ALIGN_DOUBLE + extern int etext; +# ifdef SUNOS5 +# define OS_TYPE "SUNOS5" + extern int _etext; + extern int _end; + extern char * GC_SysVGetDataStart(); +# define DATASTART (ptr_t)GC_SysVGetDataStart(0x10000, &_etext) +# define DATAEND (&_end) +# ifndef USE_MMAP +# define USE_MMAP +# endif +# ifdef USE_MMAP +# define HEAP_START (ptr_t)0x40000000 +# else +# define HEAP_START DATAEND +# endif +# define PROC_VDB +/* HEURISTIC1 reportedly no longer works under 2.7. Thus we */ +/* switched to HEURISTIC2, eventhough it creates some debugging */ +/* issues. */ +# define HEURISTIC2 +# include <unistd.h> +# define GETPAGESIZE() sysconf(_SC_PAGESIZE) + /* getpagesize() appeared to be missing from at least one */ + /* Solaris 5.4 installation. Weird. */ +# define DYNAMIC_LOADING +# endif +# ifdef SUNOS4 +# define OS_TYPE "SUNOS4" + /* [If you have a weak stomach, don't read this.] */ + /* We would like to use: */ +/* # define DATASTART ((ptr_t)((((word) (&etext)) + 0x1fff) & ~0x1fff)) */ + /* This fails occasionally, due to an ancient, but very */ + /* persistent ld bug. &etext is set 32 bytes too high. */ + /* We instead read the text segment size from the a.out */ + /* header, which happens to be mapped into our address space */ + /* at the start of the text segment. The detective work here */ + /* was done by Robert Ehrlich, Manuel Serrano, and Bernard */ + /* Serpette of INRIA. */ + /* This assumes ZMAGIC, i.e. demand-loadable executables. */ +# define TEXTSTART 0x2000 +# define DATASTART ((ptr_t)(*(int *)(TEXTSTART+0x4)+TEXTSTART)) +# define MPROTECT_VDB +# define HEURISTIC1 +# define DYNAMIC_LOADING +# endif +# ifdef DRSNX +# define CPP_WORDSZ 32 +# define OS_TYPE "DRSNX" + extern char * GC_SysVGetDataStart(); + extern int etext; +# define DATASTART (ptr_t)GC_SysVGetDataStart(0x10000, &etext) +# define MPROTECT_VDB +# define STACKBOTTOM ((ptr_t) 0xdfff0000) +# define DYNAMIC_LOADING +# endif +# ifdef LINUX +# define OS_TYPE "LINUX" +# ifdef __ELF__ +# define DATASTART GC_data_start +# define DYNAMIC_LOADING +# else + Linux Sparc non elf ? +# endif + extern int _end; +# define DATAEND (&_end) +# define SVR4 +# define STACKBOTTOM ((ptr_t) 0xf0000000) +# endif +# ifdef OPENBSD +# define OS_TYPE "OPENBSD" +# define STACKBOTTOM ((ptr_t) 0xf8000000) +# define DATASTART ((ptr_t)(&etext)) +# endif +# endif + +# ifdef I386 +# define MACH_TYPE "I386" +# define ALIGNMENT 4 /* Appears to hold for all "32 bit" compilers */ + /* except Borland. The -a4 option fixes */ + /* Borland. */ + /* Ivan Demakov: For Watcom the option is -zp4. */ +# ifndef SMALL_CONFIG +# define ALIGN_DOUBLE /* Not strictly necessary, but may give speed */ + /* improvement on Pentiums. */ +# endif +# ifdef SEQUENT +# define OS_TYPE "SEQUENT" + extern int etext; +# define DATASTART ((ptr_t)((((word) (&etext)) + 0xfff) & ~0xfff)) +# define STACKBOTTOM ((ptr_t) 0x3ffff000) +# endif +# ifdef SUNOS5 +# define OS_TYPE "SUNOS5" + extern int etext, _start; + extern char * GC_SysVGetDataStart(); +# define DATASTART GC_SysVGetDataStart(0x1000, &etext) +# define STACKBOTTOM ((ptr_t)(&_start)) +/** At least in Solaris 2.5, PROC_VDB gives wrong values for dirty bits. */ +/*# define PROC_VDB*/ +# define DYNAMIC_LOADING +# ifndef USE_MMAP +# define USE_MMAP +# endif +# ifdef USE_MMAP +# define HEAP_START (ptr_t)0x40000000 +# else +# define HEAP_START DATAEND +# endif +# endif +# ifdef SCO +# define OS_TYPE "SCO" + extern int etext; +# define DATASTART ((ptr_t)((((word) (&etext)) + 0x3fffff) \ + & ~0x3fffff) \ + +((word)&etext & 0xfff)) +# define STACKBOTTOM ((ptr_t) 0x7ffffffc) +# endif +# ifdef SCO_ELF +# define OS_TYPE "SCO_ELF" + extern int etext; +# define DATASTART ((ptr_t)(&etext)) +# define STACKBOTTOM ((ptr_t) 0x08048000) +# define DYNAMIC_LOADING +# define ELF_CLASS ELFCLASS32 +# endif +# ifdef LINUX +# define OS_TYPE "LINUX" +# define HEURISTIC1 +# undef STACK_GRAN +# define STACK_GRAN 0x10000000 + /* STACKBOTTOM is usually 0xc0000000, but this changes with */ + /* different kernel configurations. In particular, systems */ + /* with 2GB physical memory will usually move the user */ + /* address space limit, and hence initial SP to 0x80000000. */ +# if !defined(LINUX_THREADS) || !defined(REDIRECT_MALLOC) +# define MPROTECT_VDB +# else + /* We seem to get random errors in incremental mode, */ + /* possibly because Linux threads is itself a malloc client */ + /* and can't deal with the signals. */ +# endif +# ifdef __ELF__ +# define DYNAMIC_LOADING +# ifdef UNDEFINED /* includes ro data */ + extern int _etext; +# define DATASTART ((ptr_t)((((word) (&_etext)) + 0xfff) & ~0xfff)) +# endif +# include <features.h> +# if defined(__GLIBC__) && __GLIBC__ >= 2 + extern int __data_start; +# define DATASTART ((ptr_t)(&__data_start)) +# else + extern char **__environ; +# define DATASTART ((ptr_t)(&__environ)) + /* hideous kludge: __environ is the first */ + /* word in crt0.o, and delimits the start */ + /* of the data segment, no matter which */ + /* ld options were passed through. */ + /* We could use _etext instead, but that */ + /* would include .rodata, which may */ + /* contain large read-only data tables */ + /* that we'd rather not scan. */ +# endif + extern int _end; +# define DATAEND (&_end) +# else + extern int etext; +# define DATASTART ((ptr_t)((((word) (&etext)) + 0xfff) & ~0xfff)) +# endif +# endif +# ifdef CYGWIN32 +# define OS_TYPE "CYGWIN32" + extern int _data_start__; + extern int _data_end__; + extern int _bss_start__; + extern int _bss_end__; + /* For binutils 2.9.1, we have */ + /* DATASTART = _data_start__ */ + /* DATAEND = _bss_end__ */ + /* whereas for some earlier versions it was */ + /* DATASTART = _bss_start__ */ + /* DATAEND = _data_end__ */ + /* To get it right for both, we take the */ + /* minumum/maximum of the two. */ +# define MAX(x,y) ((x) > (y) ? (x) : (y)) +# define MIN(x,y) ((x) < (y) ? (x) : (y)) +# define DATASTART ((ptr_t) MIN(&_data_start__, &_bss_start__)) +# define DATAEND ((ptr_t) MAX(&_data_end__, &_bss_end__)) +# undef STACK_GRAN +# define STACK_GRAN 0x10000 +# define HEURISTIC1 +# endif +# ifdef OS2 +# define OS_TYPE "OS2" + /* STACKBOTTOM and DATASTART are handled specially in */ + /* os_dep.c. OS2 actually has the right */ + /* system call! */ +# define DATAEND /* not needed */ +# endif +# ifdef MSWIN32 +# define OS_TYPE "MSWIN32" + /* STACKBOTTOM and DATASTART are handled specially in */ + /* os_dep.c. */ +# ifndef __WATCOMC__ +# define MPROTECT_VDB +# endif +# define DATAEND /* not needed */ +# endif +# ifdef DJGPP +# define OS_TYPE "DJGPP" +# include "stubinfo.h" + extern int etext; + extern int _stklen; + extern int __djgpp_stack_limit; +# define DATASTART ((ptr_t)((((word) (&etext)) + 0x1ff) & ~0x1ff)) +/* # define STACKBOTTOM ((ptr_t)((word) _stubinfo + _stubinfo->size \ + + _stklen)) */ +# define STACKBOTTOM ((ptr_t)((word) __djgpp_stack_limit + _stklen)) + /* This may not be right. */ +# endif +# ifdef OPENBSD +# define OS_TYPE "OPENBSD" +# endif +# ifdef FREEBSD +# define OS_TYPE "FREEBSD" +# define MPROTECT_VDB +# endif +# ifdef NETBSD +# define OS_TYPE "NETBSD" +# endif +# ifdef THREE86BSD +# define OS_TYPE "THREE86BSD" +# endif +# ifdef BSDI +# define OS_TYPE "BSDI" +# endif +# if defined(OPENBSD) || defined(FREEBSD) || defined(NETBSD) \ + || defined(THREE86BSD) || defined(BSDI) +# define HEURISTIC2 + extern char etext; +# define DATASTART ((ptr_t)(&etext)) +# endif +# ifdef NEXT +# define OS_TYPE "NEXT" +# define DATASTART ((ptr_t) get_etext()) +# define STACKBOTTOM ((ptr_t)0xc0000000) +# define DATAEND /* not needed */ +# endif +# ifdef DOS4GW +# define OS_TYPE "DOS4GW" + extern long __nullarea; + extern char _end; + extern char *_STACKTOP; + /* Depending on calling conventions Watcom C either precedes + or does not precedes with undescore names of C-variables. + Make sure startup code variables always have the same names. */ + #pragma aux __nullarea "*"; + #pragma aux _end "*"; +# define STACKBOTTOM ((ptr_t) _STACKTOP) + /* confused? me too. */ +# define DATASTART ((ptr_t) &__nullarea) +# define DATAEND ((ptr_t) &_end) +# endif +# endif + +# ifdef NS32K +# define MACH_TYPE "NS32K" +# define ALIGNMENT 4 + extern char **environ; +# define DATASTART ((ptr_t)(&environ)) + /* hideous kludge: environ is the first */ + /* word in crt0.o, and delimits the start */ + /* of the data segment, no matter which */ + /* ld options were passed through. */ +# define STACKBOTTOM ((ptr_t) 0xfffff000) /* for Encore */ +# endif + +# ifdef MIPS +# define MACH_TYPE "MIPS" +# ifndef IRIX5 +# define DATASTART (ptr_t)0x10000000 + /* Could probably be slightly higher since */ + /* startup code allocates lots of stuff. */ +# else + extern int _fdata; +# define DATASTART ((ptr_t)(&_fdata)) +# ifdef USE_MMAP +# define HEAP_START (ptr_t)0x30000000 +# else +# define HEAP_START DATASTART +# endif + /* Lowest plausible heap address. */ + /* In the MMAP case, we map there. */ + /* In either case it is used to identify */ + /* heap sections so they're not */ + /* considered as roots. */ +# endif /* IRIX5 */ +# define HEURISTIC2 +/* # define STACKBOTTOM ((ptr_t)0x7fff8000) sometimes also works. */ +# ifdef ULTRIX +# define OS_TYPE "ULTRIX" +# define ALIGNMENT 4 +# endif +# ifdef RISCOS +# define OS_TYPE "RISCOS" +# define ALIGNMENT 4 /* Required by hardware */ +# endif +# ifdef IRIX5 +# define OS_TYPE "IRIX5" +# define MPROTECT_VDB +# ifdef _MIPS_SZPTR +# define CPP_WORDSZ _MIPS_SZPTR +# define ALIGNMENT (_MIPS_SZPTR/8) +# if CPP_WORDSZ != 64 +# define ALIGN_DOUBLE +# endif +# else +# define ALIGNMENT 4 +# define ALIGN_DOUBLE +# endif +# define DYNAMIC_LOADING +# endif +# endif + +# ifdef RS6000 +# define MACH_TYPE "RS6000" +# define ALIGNMENT 4 +# define DATASTART ((ptr_t)0x20000000) + extern int errno; +# define STACKBOTTOM ((ptr_t)((ulong)&errno)) +# define DYNAMIC_LOADING + /* For really old versions of AIX, this may have to be removed. */ +# endif + +# ifdef HP_PA +# define MACH_TYPE "HP_PA" +# define ALIGNMENT 4 +# define ALIGN_DOUBLE + extern int __data_start; +# define DATASTART ((ptr_t)(&__data_start)) +# if 0 + /* The following appears to work for 7xx systems running HP/UX */ + /* 9.xx Furthermore, it might result in much faster */ + /* collections than HEURISTIC2, which may involve scanning */ + /* segments that directly precede the stack. It is not the */ + /* default, since it may not work on older machine/OS */ + /* combinations. (Thanks to Raymond X.T. Nijssen for uncovering */ + /* this.) */ +# define STACKBOTTOM ((ptr_t) 0x7b033000) /* from /etc/conf/h/param.h */ +# else +# define HEURISTIC2 +# endif +# define STACK_GROWS_UP +# define DYNAMIC_LOADING +# include <unistd.h> +# define GETPAGESIZE() sysconf(_SC_PAGE_SIZE) + /* They misspelled the Posix macro? */ +# endif + +# ifdef ALPHA +# define MACH_TYPE "ALPHA" +# define ALIGNMENT 8 +# ifdef OSF1 +# define OS_TYPE "OSF1" +# define DATASTART ((ptr_t) 0x140000000) + extern _end; +# define DATAEND ((ptr_t) &_end) +# define HEURISTIC2 + /* Normally HEURISTIC2 is too conervative, since */ + /* the text segment immediately follows the stack. */ + /* Hence we give an upper pound. */ + extern int __start; +# define HEURISTIC2_LIMIT ((ptr_t)((word)(&__start) & ~(getpagesize()-1))) +# define CPP_WORDSZ 64 +# define MPROTECT_VDB +# define DYNAMIC_LOADING +# endif +# ifdef LINUX +# define OS_TYPE "LINUX" +# define CPP_WORDSZ 64 +# define STACKBOTTOM ((ptr_t) 0x120000000) +# ifdef __ELF__ +# if 0 + /* __data_start apparently disappeared in some recent releases. */ + extern int __data_start; +# define DATASTART &__data_start +# endif +# define DATASTART GC_data_start +# define DYNAMIC_LOADING +# else +# define DATASTART ((ptr_t) 0x140000000) +# endif + extern int _end; +# define DATAEND (&_end) +# define MPROTECT_VDB + /* Has only been superficially tested. May not */ + /* work on all versions. */ +# endif +# endif + +# ifdef M88K +# define MACH_TYPE "M88K" +# define ALIGNMENT 4 +# define ALIGN_DOUBLE + extern int etext; +# ifdef CX_UX +# define OS_TYPE "CX_UX" +# define DATASTART ((((word)&etext + 0x3fffff) & ~0x3fffff) + 0x10000) +# endif +# ifdef DGUX +# define OS_TYPE "DGUX" + extern char * GC_SysVGetDataStart(); +# define DATASTART (ptr_t)GC_SysVGetDataStart(0x10000, &etext) +# endif +# define STACKBOTTOM ((char*)0xf0000000) /* determined empirically */ +# endif + +# ifdef S370 +# define MACH_TYPE "S370" +# define OS_TYPE "UTS4" +# define ALIGNMENT 4 /* Required by hardware */ + extern int etext; + extern int _etext; + extern int _end; + extern char * GC_SysVGetDataStart(); +# define DATASTART (ptr_t)GC_SysVGetDataStart(0x10000, &_etext) +# define DATAEND (&_end) +# define HEURISTIC2 +# endif + +# ifndef STACK_GROWS_UP +# define STACK_GROWS_DOWN +# endif + +# ifndef CPP_WORDSZ +# define CPP_WORDSZ 32 +# endif + +# ifndef OS_TYPE +# define OS_TYPE "" +# endif + +# ifndef DATAEND + extern int end; +# define DATAEND (&end) +# endif + +# if defined(SVR4) && !defined(GETPAGESIZE) +# include <unistd.h> +# define GETPAGESIZE() sysconf(_SC_PAGESIZE) +# endif + +# ifndef GETPAGESIZE +# if defined(SUNOS5) || defined(IRIX5) +# include <unistd.h> +# endif +# define GETPAGESIZE() getpagesize() +# endif + +# if defined(SUNOS5) || defined(DRSNX) || defined(UTS4) + /* OS has SVR4 generic features. Probably others also qualify. */ +# define SVR4 +# endif + +# if defined(SUNOS5) || defined(DRSNX) + /* OS has SUNOS5 style semi-undocumented interface to dynamic */ + /* loader. */ +# define SUNOS5DL + /* OS has SUNOS5 style signal handlers. */ +# define SUNOS5SIGS +# endif + +# if CPP_WORDSZ != 32 && CPP_WORDSZ != 64 + -> bad word size +# endif + +# ifdef PCR +# undef DYNAMIC_LOADING +# undef STACKBOTTOM +# undef HEURISTIC1 +# undef HEURISTIC2 +# undef PROC_VDB +# undef MPROTECT_VDB +# define PCR_VDB +# endif + +# ifdef SRC_M3 +/* Postponed for now. */ +# undef PROC_VDB +# undef MPROTECT_VDB +# endif + +# ifdef SMALL_CONFIG +/* Presumably not worth the space it takes. */ +# undef PROC_VDB +# undef MPROTECT_VDB +# endif + +# ifdef USE_MUNMAP +# undef MPROTECT_VDB /* Can't deal with address space holes. */ +# endif + +# if !defined(PCR_VDB) && !defined(PROC_VDB) && !defined(MPROTECT_VDB) +# define DEFAULT_VDB +# endif + +# if defined(_SOLARIS_PTHREADS) && !defined(SOLARIS_THREADS) +# define SOLARIS_THREADS +# endif +# if defined(IRIX_THREADS) && !defined(IRIX5) +--> inconsistent configuration +# endif +# if defined(IRIX_JDK_THREADS) && !defined(IRIX5) +--> inconsistent configuration +# endif +# if defined(LINUX_THREADS) && !defined(LINUX) +--> inconsistent configuration +# endif +# if defined(SOLARIS_THREADS) && !defined(SUNOS5) +--> inconsistent configuration +# endif +# if defined(PCR) || defined(SRC_M3) || \ + defined(SOLARIS_THREADS) || defined(WIN32_THREADS) || \ + defined(IRIX_THREADS) || defined(LINUX_THREADS) || \ + defined(IRIX_JDK_THREADS) +# define THREADS +# endif + +# if defined(HP_PA) || defined(M88K) || defined(POWERPC) \ + || (defined(I386) && defined(OS2)) || defined(UTS4) || defined(LINT) + /* Use setjmp based hack to mark from callee-save registers. */ +# define USE_GENERIC_PUSH_REGS +# endif +# if defined(SPARC) && !defined(LINUX) +# define SAVE_CALL_CHAIN +# define ASM_CLEAR_CODE /* Stack clearing is crucial, and we */ + /* include assembly code to do it well. */ +# endif + +# endif diff --git a/gc/include/weakpointer.h b/gc/include/weakpointer.h new file mode 100644 index 0000000..84906b0 --- /dev/null +++ b/gc/include/weakpointer.h @@ -0,0 +1,221 @@ +#ifndef _weakpointer_h_ +#define _weakpointer_h_ + +/**************************************************************************** + +WeakPointer and CleanUp + + Copyright (c) 1991 by Xerox Corporation. All rights reserved. + + THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED + OR IMPLIED. ANY USE IS AT YOUR OWN RISK. + + Permission is hereby granted to copy this code for any purpose, + provided the above notices are retained on all copies. + + Last modified on Mon Jul 17 18:16:01 PDT 1995 by ellis + +****************************************************************************/ + +/**************************************************************************** + +WeakPointer + +A weak pointer is a pointer to a heap-allocated object that doesn't +prevent the object from being garbage collected. Weak pointers can be +used to track which objects haven't yet been reclaimed by the +collector. A weak pointer is deactivated when the collector discovers +its referent object is unreachable by normal pointers (reachability +and deactivation are defined more precisely below). A deactivated weak +pointer remains deactivated forever. + +****************************************************************************/ + + +template< class T > class WeakPointer { +public: + +WeakPointer( T* t = 0 ) + /* Constructs a weak pointer for *t. t may be null. It is an error + if t is non-null and *t is not a collected object. */ + {impl = _WeakPointer_New( t );} + +T* Pointer() + /* wp.Pointer() returns a pointer to the referent object of wp or + null if wp has been deactivated (because its referent object + has been discovered unreachable by the collector). */ + {return (T*) _WeakPointer_Pointer( this->impl );} + +int operator==( WeakPointer< T > wp2 ) + /* Given weak pointers wp1 and wp2, if wp1 == wp2, then wp1 and + wp2 refer to the same object. If wp1 != wp2, then either wp1 + and wp2 don't refer to the same object, or if they do, one or + both of them has been deactivated. (Note: If objects t1 and t2 + are never made reachable by their clean-up functions, then + WeakPointer<T>(t1) == WeakPointer<T>(t2) if and only t1 == t2.) */ + {return _WeakPointer_Equal( this->impl, wp2.impl );} + +int Hash() + /* Returns a hash code suitable for use by multiplicative- and + division-based hash tables. If wp1 == wp2, then wp1.Hash() == + wp2.Hash(). */ + {return _WeakPointer_Hash( this->impl );} + +private: +void* impl; +}; + +/***************************************************************************** + +CleanUp + +A garbage-collected object can have an associated clean-up function +that will be invoked some time after the collector discovers the +object is unreachable via normal pointers. Clean-up functions can be +used to release resources such as open-file handles or window handles +when their containing objects become unreachable. If a C++ object has +a non-empty explicit destructor (i.e. it contains programmer-written +code), the destructor will be automatically registered as the object's +initial clean-up function. + +There is no guarantee that the collector will detect every unreachable +object (though it will find almost all of them). Clients should not +rely on clean-up to cause some action to occur immediately -- clean-up +is only a mechanism for improving resource usage. + +Every object with a clean-up function also has a clean-up queue. When +the collector finds the object is unreachable, it enqueues it on its +queue. The clean-up function is applied when the object is removed +from the queue. By default, objects are enqueued on the garbage +collector's queue, and the collector removes all objects from its +queue after each collection. If a client supplies another queue for +objects, it is his responsibility to remove objects (and cause their +functions to be called) by polling it periodically. + +Clean-up queues allow clean-up functions accessing global data to +synchronize with the main program. Garbage collection can occur at any +time, and clean-ups invoked by the collector might access data in an +inconsistent state. A client can control this by defining an explicit +queue for objects and polling it at safe points. + +The following definitions are used by the specification below: + +Given a pointer t to a collected object, the base object BO(t) is the +value returned by new when it created the object. (Because of multiple +inheritance, t and BO(t) may not be the same address.) + +A weak pointer wp references an object *t if BO(wp.Pointer()) == +BO(t). + +***************************************************************************/ + +template< class T, class Data > class CleanUp { +public: + +static void Set( T* t, void c( Data* d, T* t ), Data* d = 0 ) + /* Sets the clean-up function of object BO(t) to be <c, d>, + replacing any previously defined clean-up function for BO(t); c + and d can be null, but t cannot. Sets the clean-up queue for + BO(t) to be the collector's queue. When t is removed from its + clean-up queue, its clean-up will be applied by calling c(d, + t). It is an error if *t is not a collected object. */ + {_CleanUp_Set( t, c, d );} + +static void Call( T* t ) + /* Sets the new clean-up function for BO(t) to be null and, if the + old one is non-null, calls it immediately, even if BO(t) is + still reachable. Deactivates any weak pointers to BO(t). */ + {_CleanUp_Call( t );} + +class Queue {public: + Queue() + /* Constructs a new queue. */ + {this->head = _CleanUp_Queue_NewHead();} + + void Set( T* t ) + /* q.Set(t) sets the clean-up queue of BO(t) to be q. */ + {_CleanUp_Queue_Set( this->head, t );} + + int Call() + /* If q is non-empty, q.Call() removes the first object and + calls its clean-up function; does nothing if q is + empty. Returns true if there are more objects in the + queue. */ + {return _CleanUp_Queue_Call( this->head );} + + private: + void* head; + }; +}; + +/********************************************************************** + +Reachability and Clean-up + +An object O is reachable if it can be reached via a non-empty path of +normal pointers from the registers, stacks, global variables, or an +object with a non-null clean-up function (including O itself), +ignoring pointers from an object to itself. + +This definition of reachability ensures that if object B is accessible +from object A (and not vice versa) and if both A and B have clean-up +functions, then A will always be cleaned up before B. Note that as +long as an object with a clean-up function is contained in a cycle of +pointers, it will always be reachable and will never be cleaned up or +collected. + +When the collector finds an unreachable object with a null clean-up +function, it atomically deactivates all weak pointers referencing the +object and recycles its storage. If object B is accessible from object +A via a path of normal pointers, A will be discovered unreachable no +later than B, and a weak pointer to A will be deactivated no later +than a weak pointer to B. + +When the collector finds an unreachable object with a non-null +clean-up function, the collector atomically deactivates all weak +pointers referencing the object, redefines its clean-up function to be +null, and enqueues it on its clean-up queue. The object then becomes +reachable again and remains reachable at least until its clean-up +function executes. + +The clean-up function is assured that its argument is the only +accessible pointer to the object. Nothing prevents the function from +redefining the object's clean-up function or making the object +reachable again (for example, by storing the pointer in a global +variable). + +If the clean-up function does not make its object reachable again and +does not redefine its clean-up function, then the object will be +collected by a subsequent collection (because the object remains +unreachable and now has a null clean-up function). If the clean-up +function does make its object reachable again and a clean-up function +is subsequently redefined for the object, then the new clean-up +function will be invoked the next time the collector finds the object +unreachable. + +Note that a destructor for a collected object cannot safely redefine a +clean-up function for its object, since after the destructor executes, +the object has been destroyed into "raw memory". (In most +implementations, destroying an object mutates its vtbl.) + +Finally, note that calling delete t on a collected object first +deactivates any weak pointers to t and then invokes its clean-up +function (destructor). + +**********************************************************************/ + +extern "C" { + void* _WeakPointer_New( void* t ); + void* _WeakPointer_Pointer( void* wp ); + int _WeakPointer_Equal( void* wp1, void* wp2 ); + int _WeakPointer_Hash( void* wp ); + void _CleanUp_Set( void* t, void (*c)( void* d, void* t ), void* d ); + void _CleanUp_Call( void* t ); + void* _CleanUp_Queue_NewHead (); + void _CleanUp_Queue_Set( void* h, void* t ); + int _CleanUp_Queue_Call( void* h ); +} + +#endif /* _weakpointer_h_ */ + + |