Updates from 0.2.1 into 0.2.1-inu-1.5release-0-2-1-inu-1-5

1 files changed, 145 insertions, 0 deletions

diff --git a/gc/include/gc_mark.h b/gc/include/gc_mark.h
new file mode 100644
index 0000000..0856d16
--- /dev/null
+++ b/gc/include/gc_mark.h
@@ -0,0 +1,145 @@
+/*
+ * Copyright (c) 1991-1994 by Xerox Corporation.  All rights reserved.
+ * Copyright (c) 2001 by Hewlett-Packard Company. 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 contains interfaces to the GC marker that are likely to be useful to
+ * clients that provide detailed heap layout information to the collector.
+ * This interface should not be used by normal C or C++ clients.
+ * It will be useful to runtimes for other languages.
+ * 
+ * Note that this file is not "namespace-clean", i.e. it introduces names
+ * not prefixed with GC_, which may collide with the client's names.  It
+ * should be included only in those few places that directly provide
+ * information to the collector.
+ */
+#ifndef GC_MARK_H
+# define GC_MARK_H
+
+# ifndef GC_H
+#   include "gc.h"
+# endif
+
+/* A client supplied mark procedure.  Returns new mark stack pointer.	*/
+/* Primary effect should be to push new entries on the mark stack.	*/
+/* Mark stack pointer values are passed and returned explicitly.	*/
+/* Global variables decribing mark stack are not necessarily valid.	*/
+/* (This usually saves a few cycles by keeping things in registers.)	*/
+/* Assumed to scan about GC_PROC_BYTES on average.  If it needs to do	*/
+/* much more work than that, it should do it in smaller pieces by	*/
+/* pushing itself back on the mark stack.				*/
+/* Note that it should always do some work (defined as marking some	*/
+/* objects) before pushing more than one entry on the mark stack.	*/
+/* This is required to ensure termination in the event of mark stack	*/
+/* overflows.								*/
+/* This procedure is always called with at least one empty entry on the */
+/* mark stack.								*/
+/* Currently we require that mark procedures look for pointers in a	*/
+/* subset of the places the conservative marker would.  It must be safe	*/
+/* to invoke the normal mark procedure instead.				*/
+/* WARNING: Such a mark procedure may be invoked on an unused object    */
+/* residing on a free list.  Such objects are cleared, except for a	*/
+/* free list link field in the first word.  Thus mark procedures may	*/
+/* not count on the presence of a type descriptor, and must handle this	*/
+/* case correctly somehow.						*/
+# define GC_PROC_BYTES 100
+struct GC_ms_entry;
+typedef struct GC_ms_entry * (*GC_mark_proc) GC_PROTO((
+		GC_word * addr, struct GC_ms_entry * mark_stack_ptr,
+		struct GC_ms_entry * mark_stack_limit, GC_word env));
+
+# define GC_LOG_MAX_MARK_PROCS 6
+# define GC_MAX_MARK_PROCS (1 << GC_LOG_MAX_MARK_PROCS)
+
+/* In a few cases it's necessary to assign statically known indices to	*/
+/* certain mark procs.  Thus we reserve a few for well known clients.	*/
+/* (This is necessary if mark descriptors are compiler generated.)	*/
+#define GC_RESERVED_MARK_PROCS 8
+#   define GC_GCJ_RESERVED_MARK_PROC_INDEX 0
+
+/* Object descriptors on mark stack or in objects.  Low order two	*/
+/* bits are tags distinguishing among the following 4 possibilities	*/
+/* for the high order 30 bits.						*/
+#define GC_DS_TAG_BITS 2
+#define GC_DS_TAGS   ((1 << GC_DS_TAG_BITS) - 1)
+#define GC_DS_LENGTH 0	/* The entire word is a length in bytes that	*/
+			/* must be a multiple of 4.			*/
+#define GC_DS_BITMAP 1	/* 30 (62) bits are a bitmap describing pointer	*/
+			/* fields.  The msb is 1 iff the first word	*/
+			/* is a pointer.				*/
+			/* (This unconventional ordering sometimes	*/
+			/* makes the marker slightly faster.)		*/
+			/* Zeroes indicate definite nonpointers.  Ones	*/
+			/* indicate possible pointers.			*/
+			/* Only usable if pointers are word aligned.	*/
+#define GC_DS_PROC   2
+			/* The objects referenced by this object can be */
+			/* pushed on the mark stack by invoking		*/
+			/* PROC(descr).  ENV(descr) is passed as the	*/
+			/* last argument.				*/
+#   define GC_MAKE_PROC(proc_index, env) \
+	    (((((env) << GC_LOG_MAX_MARK_PROCS) \
+	       | (proc_index)) << GC_DS_TAG_BITS) | GC_DS_PROC)
+#define GC_DS_PER_OBJECT 3  /* The real descriptor is at the		*/
+			/* byte displacement from the beginning of the	*/
+			/* object given by descr & ~DS_TAGS		*/
+			/* If the descriptor is negative, the real	*/
+			/* descriptor is at (*<object_start>) -		*/
+			/* (descr & ~DS_TAGS) - GC_INDIR_PER_OBJ_BIAS	*/
+			/* The latter alternative can be used if each	*/
+			/* object contains a type descriptor in the	*/
+			/* first word.					*/
+			/* Note that in multithreaded environments	*/
+			/* per object descriptors maust be located in	*/
+			/* either the first two or last two words of	*/
+			/* the object, since only those are guaranteed	*/
+			/* to be cleared while the allocation lock is	*/
+			/* held.					*/
+#define GC_INDIR_PER_OBJ_BIAS 0x10
+			
+extern GC_PTR GC_least_plausible_heap_addr;
+extern GC_PTR GC_greatest_plausible_heap_addr;
+			/* Bounds on the heap.  Guaranteed valid	*/
+			/* Likely to include future heap expansion.	*/
+
+/* Handle nested references in a custom mark procedure.			*/
+/* Check if obj is a valid object. If so, ensure that it is marked.	*/
+/* If it was not previously marked, push its contents onto the mark 	*/
+/* stack for future scanning.  The object will then be scanned using	*/
+/* its mark descriptor.  						*/
+/* Returns the new mark stack pointer.					*/
+/* Handles mark stack overflows correctly.				*/
+/* Since this marks first, it makes progress even if there are mark	*/
+/* stack overflows.							*/
+/* Src is the address of the pointer to obj, which is used only		*/
+/* for back pointer-based heap debugging.				*/
+/* It is strongly recommended that most objects be handled without mark	*/
+/* procedures, e.g. with bitmap descriptors, and that mark procedures	*/
+/* be reserved for exceptional cases.  That will ensure that 		*/
+/* performance of this call is not extremely performance critical.	*/
+/* (Otherwise we would need to inline GC_mark_and_push completely,	*/
+/* which would tie the client code to a fixed colllector version.)	*/
+struct GC_ms_entry *GC_mark_and_push
+		GC_PROTO((GC_PTR obj,
+			  struct GC_ms_entry * mark_stack_ptr,
+		          struct GC_ms_entry * mark_stack_limit, GC_PTR *src));
+
+#define GC_MARK_AND_PUSH(obj, msp, lim, src) \
+	(((GC_word)obj >= (GC_word)GC_least_plausible_heap_addr && \
+	  (GC_word)obj <= (GC_word)GC_greatest_plausible_heap_addr)? \
+	  GC_mark_and_push(obj, msp, lim, src) : \
+	  msp)
+
+#endif  /* GC_MARK_H */
+