Fix collection of objects referenced only from GC_mark_stack_X variables

* include/private/gc_pmark.h (mse): Move to gc_priv.h (as used by
GC_mark_stack_limit, GC_mark_stack_top, GC_mark_stack).
* include/private/gc_pmark.h (GC_mark_stack_limit, GC_mark_stack_top,
GC_mark_stack): Remove variable declaration.
* include/private/gc_priv.h (_GC_arrays): Add _mark_stack,
_mark_stack_limit, _mark_stack_top fields.
* include/private/gc_priv.h (GC_mark_stack_limit, GC_mark_stack_top,
GC_mark_stack): Define macro (redirecting to the corresponding field
of GC_arrays).
* mark.c (GC_mark_stack, GC_mark_stack_limit, GC_mark_stack_top):
Remove variable; move comment to gc_priv.h.
* mark.c (GC_push_marked1, GC_push_marked2, GC_push_marked4): Undefine
GC_mark_stack_top and GC_mark_stack_limit macros (before redefining
them to local variables) at function start, redefine them back to the
corresponding field of GC_arrays at function exit.

diff --git a/include/private/gc_pmark.h b/include/private/gc_pmark.h
index 3aa67a9b6c3f182923e07feed17917e1ecfd1201..7e302d20d2749f840bd0988986472c7ccb64f0ab 100644 (file)
--- a/include/private/gc_pmark.h
+++ b/include/private/gc_pmark.h
@@ -69,24 +69,8 @@ GC_EXTERN unsigned GC_n_mark_procs;
 /* Number of mark stack entries to discard on overflow. */
 #define GC_MARK_STACK_DISCARDS (INITIAL_MARK_STACK_SIZE/8)
 
-typedef struct GC_ms_entry {
-    ptr_t mse_start;    /* First word of object, word aligned.  */
-    GC_word mse_descr;  /* Descriptor; low order two bits are tags,     */
-                        /* as described in gc_mark.h.                   */
-} mse;
-
 GC_EXTERN size_t GC_mark_stack_size;
 
-GC_EXTERN mse * GC_mark_stack_limit;
-
-#ifdef PARALLEL_MARK
-  GC_EXTERN mse * volatile GC_mark_stack_top;
-#else
-  GC_EXTERN mse * GC_mark_stack_top;
-#endif
-
-GC_EXTERN mse * GC_mark_stack;
-
 #ifdef PARALLEL_MARK
     /*
      * Allow multiple threads to participate in the marking process.

diff --git a/include/private/gc_priv.h b/include/private/gc_priv.h
index f0e6cffa2fcf91372c8c92c52801dbffa23e2c3e..3fdb68743bc6d14d4251b9a22a23ccf5d6f20efc 100644 (file)
--- a/include/private/gc_priv.h
+++ b/include/private/gc_priv.h
@@ -965,6 +965,12 @@ struct roots {
 # endif
 #endif /* !MAX_HEAP_SECTS */
 
+typedef struct GC_ms_entry {
+    ptr_t mse_start;    /* First word of object, word aligned.  */
+    word mse_descr;     /* Descriptor; low order two bits are tags,     */
+                        /* as described in gc_mark.h.                   */
+} mse;
+
 /* Lists of all heap blocks and free lists      */
 /* as well as other random data structures      */
 /* that should not be scanned by the            */
@@ -1033,6 +1039,17 @@ struct _GC_arrays {
   ptr_t _scratch_last_end_ptr;
         /* Used by headers.c, and can easily appear to point to */
         /* heap.                                                */
+  mse *_mark_stack;
+        /* Limits of stack for GC_mark routine.  All ranges     */
+        /* between GC_mark_stack (incl.) and GC_mark_stack_top  */
+        /* (incl.) still need to be marked from.                */
+  mse *_mark_stack_limit;
+# ifdef PARALLEL_MARK
+    mse *volatile _mark_stack_top;
+        /* Updated only with mark lock held, but read asynchronously.   */
+# else
+    mse *_mark_stack_top;
+# endif
   GC_mark_proc _mark_procs[MAX_MARK_PROCS];
         /* Table of user-defined mark procedures.  There is     */
         /* a small number of these, which can be referenced     */
@@ -1182,6 +1199,9 @@ GC_API_PRIV GC_FAR struct _GC_arrays GC_arrays;
 #define GC_large_allocd_bytes GC_arrays._large_allocd_bytes
 #define GC_large_free_bytes GC_arrays._large_free_bytes
 #define GC_last_heap_addr GC_arrays._last_heap_addr
+#define GC_mark_stack GC_arrays._mark_stack
+#define GC_mark_stack_limit GC_arrays._mark_stack_limit
+#define GC_mark_stack_top GC_arrays._mark_stack_top
 #define GC_mark_procs GC_arrays._mark_procs
 #define GC_max_heapsize GC_arrays._max_heapsize
 #define GC_max_large_allocd_bytes GC_arrays._max_large_allocd_bytes

diff --git a/mark.c b/mark.c
index d47f4550e56cf866f31d1df1ec24cd65b431a929..825c9c86ce93ecaa2ac5b7d34aedf4e52eb7d1ef 100644 (file)
--- a/mark.c
+++ b/mark.c
@@ -96,30 +96,18 @@ GC_INNER unsigned GC_n_kinds = GC_N_KINDS_INITIAL_VALUE;
                 /* grow dynamically.                                    */
 # endif
 
-/*
- * Limits of stack for GC_mark routine.
- * All ranges between GC_mark_stack(incl.) and GC_mark_stack_top(incl.) still
- * need to be marked from.
- */
-
 STATIC word GC_n_rescuing_pages = 0;
                                 /* Number of dirty pages we marked from */
                                 /* excludes ptrfree pages, etc.         */
 
-GC_INNER mse * GC_mark_stack = NULL;
-GC_INNER mse * GC_mark_stack_limit = NULL;
 GC_INNER size_t GC_mark_stack_size = 0;
 
 #ifdef PARALLEL_MARK
-  GC_INNER mse * volatile GC_mark_stack_top = NULL;
-        /* Updated only with mark lock held, but read asynchronously.   */
   STATIC volatile AO_t GC_first_nonempty = 0;
         /* Lowest entry on mark stack   */
         /* that may be nonempty.        */
         /* Updated only by initiating   */
         /* thread.                      */
-#else
-  GC_INNER mse * GC_mark_stack_top = NULL;
 #endif
 
 GC_INNER mark_state_t GC_mark_state = MS_NONE;
@@ -1586,6 +1574,9 @@ STATIC void GC_push_marked1(struct hblk *h, hdr *hhdr)
     ptr_t least_ha = GC_least_plausible_heap_addr;
     mse * mark_stack_top = GC_mark_stack_top;
     mse * mark_stack_limit = GC_mark_stack_limit;
+
+#   undef GC_mark_stack_top
+#   undef GC_mark_stack_limit
 #   define GC_mark_stack_top mark_stack_top
 #   define GC_mark_stack_limit mark_stack_limit
 #   define GC_greatest_plausible_heap_addr greatest_ha
@@ -1612,7 +1603,8 @@ STATIC void GC_push_marked1(struct hblk *h, hdr *hhdr)
 #   undef GC_least_plausible_heap_addr
 #   undef GC_mark_stack_top
 #   undef GC_mark_stack_limit
-
+#   define GC_mark_stack_limit GC_arrays._mark_stack_limit
+#   define GC_mark_stack_top GC_arrays._mark_stack_top
     GC_mark_stack_top = mark_stack_top;
 }
 
@@ -1634,6 +1626,8 @@ STATIC void GC_push_marked2(struct hblk *h, hdr *hhdr)
     mse * mark_stack_top = GC_mark_stack_top;
     mse * mark_stack_limit = GC_mark_stack_limit;
 
+#   undef GC_mark_stack_top
+#   undef GC_mark_stack_limit
 #   define GC_mark_stack_top mark_stack_top
 #   define GC_mark_stack_limit mark_stack_limit
 #   define GC_greatest_plausible_heap_addr greatest_ha
@@ -1661,7 +1655,8 @@ STATIC void GC_push_marked2(struct hblk *h, hdr *hhdr)
 #   undef GC_least_plausible_heap_addr
 #   undef GC_mark_stack_top
 #   undef GC_mark_stack_limit
-
+#   define GC_mark_stack_limit GC_arrays._mark_stack_limit
+#   define GC_mark_stack_top GC_arrays._mark_stack_top
     GC_mark_stack_top = mark_stack_top;
 }
 
@@ -1682,6 +1677,9 @@ STATIC void GC_push_marked4(struct hblk *h, hdr *hhdr)
     ptr_t least_ha = GC_least_plausible_heap_addr;
     mse * mark_stack_top = GC_mark_stack_top;
     mse * mark_stack_limit = GC_mark_stack_limit;
+
+#   undef GC_mark_stack_top
+#   undef GC_mark_stack_limit
 #   define GC_mark_stack_top mark_stack_top
 #   define GC_mark_stack_limit mark_stack_limit
 #   define GC_greatest_plausible_heap_addr greatest_ha
@@ -1710,6 +1708,8 @@ STATIC void GC_push_marked4(struct hblk *h, hdr *hhdr)
 #   undef GC_least_plausible_heap_addr
 #   undef GC_mark_stack_top
 #   undef GC_mark_stack_limit
+#   define GC_mark_stack_limit GC_arrays._mark_stack_limit
+#   define GC_mark_stack_top GC_arrays._mark_stack_top
     GC_mark_stack_top = mark_stack_top;
 }