X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=blobdiff_plain;f=mono%2Fmetadata%2Fsgen-alloc.c;h=02a1d45bd34dd834bb7c03717fe094fd9ca53bab;hb=2facf4db1f2cc64f9d934ec6ed880765d9ed9074;hp=ffdb0c485528c572ad5d160ceeb7ad31fac4aa4b;hpb=b57fcaa28b7108c701b378a27f772917c225d033;p=mono.git

diff --git a/mono/metadata/sgen-alloc.c b/mono/metadata/sgen-alloc.c
index ffdb0c48552..02a1d45bd34 100644
--- a/mono/metadata/sgen-alloc.c
+++ b/mono/metadata/sgen-alloc.c
@@ -145,6 +145,34 @@ alloc_degraded (MonoVTable *vtable, size_t size, gboolean for_mature)
 	return p;
 }
 
+static void
+zero_tlab_if_necessary (void *p, size_t size)
+{
+	if (nursery_clear_policy == CLEAR_AT_TLAB_CREATION) {
+		memset (p, 0, size);
+	} else {
+		/*
+		 * This function is called for all allocations in
+		 * TLABs.  TLABs originate from fragments, which are
+		 * initialized to be faux arrays.  The remainder of
+		 * the fragments are zeroed out at initialization for
+		 * CLEAR_AT_GC, so here we just need to make sure that
+		 * the array header is zeroed.  Since we don't know
+		 * whether we're called for the start of a fragment or
+		 * for somewhere in between, we zero in any case, just
+		 * to make sure.
+		 */
+
+		if (size >= sizeof (MonoArray))
+			memset (p, 0, sizeof (MonoArray));
+		else {
+			static guint8 zeros [sizeof (MonoArray)];
+
+			SGEN_ASSERT (0, !memcmp (p, zeros, size), "TLAB segment must be zeroed out.");
+		}
+	}
+}
+
 /*
  * Provide a variant that takes just the vtable for small fixed-size objects.
  * The aligned size is already computed and stored in vt->gc_descr.
@@ -273,9 +301,7 @@ mono_gc_alloc_obj_nolock (MonoVTable *vtable, size_t size)
 					g_assert (0);
 				}
 
-				if (nursery_clear_policy == CLEAR_AT_TLAB_CREATION) {
-					memset (p, 0, size);
-				}
+				zero_tlab_if_necessary (p, size);
 			} else {
 				size_t alloc_size = 0;
 				if (TLAB_START)
@@ -304,9 +330,7 @@ mono_gc_alloc_obj_nolock (MonoVTable *vtable, size_t size)
 				TLAB_REAL_END = TLAB_START + alloc_size;
 				TLAB_TEMP_END = TLAB_START + MIN (SGEN_SCAN_START_SIZE, alloc_size);
 
-				if (nursery_clear_policy == CLEAR_AT_TLAB_CREATION) {
-					memset (TLAB_START, 0, alloc_size);
-				}
+				zero_tlab_if_necessary (TLAB_START, alloc_size);
 
 				/* Allocate from the TLAB */
 				p = (void*)TLAB_NEXT;
@@ -361,8 +385,7 @@ mono_gc_try_alloc_obj_nolock (MonoVTable *vtable, size_t size)
 		sgen_set_nursery_scan_start ((char*)p);
 
 		/*FIXME we should use weak memory ops here. Should help specially on x86. */
-		if (nursery_clear_policy == CLEAR_AT_TLAB_CREATION)
-			memset (p, 0, size);
+		zero_tlab_if_necessary (p, size);
 	} else {
 		int available_in_tlab;
 		char *real_end;
@@ -391,8 +414,7 @@ mono_gc_try_alloc_obj_nolock (MonoVTable *vtable, size_t size)
 			if (!p)
 				return NULL;
 
-			if (nursery_clear_policy == CLEAR_AT_TLAB_CREATION)
-				memset (p, 0, size);			
+			zero_tlab_if_necessary (p, size);
 		} else {
 			size_t alloc_size = 0;
 
@@ -408,8 +430,7 @@ mono_gc_try_alloc_obj_nolock (MonoVTable *vtable, size_t size)
 			TLAB_TEMP_END = new_next + MIN (SGEN_SCAN_START_SIZE, alloc_size);
 			sgen_set_nursery_scan_start ((char*)p);
 
-			if (nursery_clear_policy == CLEAR_AT_TLAB_CREATION)
-				memset (new_next, 0, alloc_size);
+			zero_tlab_if_necessary (new_next, alloc_size);
 
 			MONO_GC_NURSERY_TLAB_ALLOC ((mword)new_next, alloc_size);
 		}
@@ -799,7 +820,8 @@ create_allocator (int atype)
 		 * case compare signed to distinguish between them.
 		 */
 		mono_mb_emit_ldarg (mb, 1);
-		mono_mb_emit_ptr (mb, (gpointer) MONO_ARRAY_MAX_INDEX);
+		mono_mb_emit_icon (mb, MONO_ARRAY_MAX_INDEX);
+		mono_mb_emit_byte (mb, CEE_CONV_U);
 		pos = mono_mb_emit_short_branch (mb, CEE_BLE_UN_S);
 
 		mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);