Update to NSPR 4.10.2.

nspr/lib/ds/plarena.h

 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #ifndef plarena_h___
 #define plarena_h___
 /*
  * Lifetime-based fast allocation, inspired by much prior art, including
  * "Fast Allocation and Deallocation of Memory Based on Object Lifetimes"
@@ skipping 40 matching lines @@
     PLArena     first;          /* first arena in pool list */
     PLArena     *current;       /* arena from which to allocate space */
     PRUint32    arenasize;      /* net exact size of a new arena */
     PRUword     mask;           /* alignment mask (power-of-2 - 1) */
 #ifdef PL_ARENAMETER
     PLArenaStats stats;
 #endif
 };
 
 /*
+ * WARNING: The PL_MAKE_MEM_ macros are for internal use by NSPR. Do NOT use
+ * them in your code.
+ *
+ * NOTE: Valgrind support to be added.
+ *
+ * The PL_MAKE_MEM_ macros are modeled after the MOZ_MAKE_MEM_ macros in
+ * Mozilla's mfbt/MemoryChecking.h. Only AddressSanitizer is supported now.
+ *
+ * Provides a common interface to the ASan (AddressSanitizer) and Valgrind
+ * functions used to mark memory in certain ways. In detail, the following
+ * three macros are provided:
+ *
+ *   PL_MAKE_MEM_NOACCESS  - Mark memory as unsafe to access (e.g. freed)
+ *   PL_MAKE_MEM_UNDEFINED - Mark memory as accessible, with content undefined
+ *   PL_MAKE_MEM_DEFINED - Mark memory as accessible, with content defined
+ *
+ * With Valgrind in use, these directly map to the three respective Valgrind
+ * macros. With ASan in use, the NOACCESS macro maps to poisoning the memory,
+ * while the UNDEFINED/DEFINED macros unpoison memory.
+ *
+ * With no memory checker available, all macros expand to the empty statement.
+ */
+
+/* WARNING: PL_SANITIZE_ADDRESS is for internal use by this header. Do NOT
+ * define or test this macro in your code.
+ */
+#if defined(__has_feature)
+#if __has_feature(address_sanitizer)
+#define PL_SANITIZE_ADDRESS 1
+#endif
+#elif defined(__SANITIZE_ADDRESS__)
+#define PL_SANITIZE_ADDRESS 1
+#endif
+
+#if defined(PL_SANITIZE_ADDRESS)
+
+/* These definitions are usually provided through the
+ * sanitizer/asan_interface.h header installed by ASan.
+ * See https://code.google.com/p/address-sanitizer/wiki/ManualPoisoning
+ */
+
+void __asan_poison_memory_region(void const volatile *addr, size_t size);
+void __asan_unpoison_memory_region(void const volatile *addr, size_t size);
+
+#define PL_MAKE_MEM_NOACCESS(addr, size) \
+    __asan_poison_memory_region((addr), (size))
+
+#define PL_MAKE_MEM_UNDEFINED(addr, size) \
+    __asan_unpoison_memory_region((addr), (size))
+
+#define PL_MAKE_MEM_DEFINED(addr, size) \
+    __asan_unpoison_memory_region((addr), (size))
+
+#else
+
+#define PL_MAKE_MEM_NOACCESS(addr, size)
+#define PL_MAKE_MEM_UNDEFINED(addr, size)
+#define PL_MAKE_MEM_DEFINED(addr, size)
+
+#endif
+
+/*
  * If the including .c file uses only one power-of-2 alignment, it may define
  * PL_ARENA_CONST_ALIGN_MASK to the alignment mask and save a few instructions
  * per ALLOCATE and GROW.
  */
 #ifdef PL_ARENA_CONST_ALIGN_MASK
 #define PL_ARENA_ALIGN(pool, n) (((PRUword)(n) + PL_ARENA_CONST_ALIGN_MASK) \
                                 & ~PL_ARENA_CONST_ALIGN_MASK)
 
 #define PL_INIT_ARENA_POOL(pool, name, size) \
         PL_InitArenaPool(pool, name, size, PL_ARENA_CONST_ALIGN_MASK + 1)
 #else
 #define PL_ARENA_ALIGN(pool, n) (((PRUword)(n) + (pool)->mask) & ~(pool)->mask)
 #endif
 
 #define PL_ARENA_ALLOCATE(p, pool, nb) \
     PR_BEGIN_MACRO \
         PLArena *_a = (pool)->current; \
         PRUint32 _nb = PL_ARENA_ALIGN(pool, nb); \
         PRUword _p = _a->avail; \
         PRUword _q = _p + _nb; \
-        if (_q > _a->limit) \
+        if (_q > _a->limit) { \
             _p = (PRUword)PL_ArenaAllocate(pool, _nb); \
-        else \
+        } else { \
             _a->avail = _q; \
+        } \
         p = (void *)_p; \
+        PL_MAKE_MEM_UNDEFINED(p, nb); \
         PL_ArenaCountAllocation(pool, nb); \
     PR_END_MACRO
 
 #define PL_ARENA_GROW(p, pool, size, incr) \
     PR_BEGIN_MACRO \
         PLArena *_a = (pool)->current; \
         PRUint32 _incr = PL_ARENA_ALIGN(pool, incr); \
         PRUword _p = _a->avail; \
         PRUword _q = _p + _incr; \
         if (_p == (PRUword)(p) + PL_ARENA_ALIGN(pool, size) && \
             _q <= _a->limit) { \
+            PL_MAKE_MEM_UNDEFINED((unsigned char *)(p) + size, incr); \
             _a->avail = _q; \
             PL_ArenaCountInplaceGrowth(pool, size, incr); \
         } else { \
             p = PL_ArenaGrow(pool, p, size, incr); \
         } \
         PL_ArenaCountGrowth(pool, size, incr); \
     PR_END_MACRO
 
 #define PL_ARENA_MARK(pool) ((void *) (pool)->current->avail)
 #define PR_UPTRDIFF(p,q) ((PRUword)(p) - (PRUword)(q))
 
 #define PL_CLEAR_UNUSED_PATTERN(a, pattern) \
-           (PR_ASSERT((a)->avail <= (a)->limit), \
-           memset((void*)(a)->avail, (pattern), (a)->limit - (a)->avail))
+    PR_BEGIN_MACRO \
+        PR_ASSERT((a)->avail <= (a)->limit); \
+        PL_MAKE_MEM_UNDEFINED((void*)(a)->avail, (a)->limit - (a)->avail); \
+        memset((void*)(a)->avail, (pattern), (a)->limit - (a)->avail); \
+    PR_END_MACRO
 #ifdef DEBUG
 #define PL_FREE_PATTERN 0xDA
 #define PL_CLEAR_UNUSED(a) PL_CLEAR_UNUSED_PATTERN((a), PL_FREE_PATTERN)
-#define PL_CLEAR_ARENA(a)  memset((void*)(a), PL_FREE_PATTERN, \
-                           (a)->limit - (PRUword)(a))
+#define PL_CLEAR_ARENA(a) \
+    PR_BEGIN_MACRO \
+        PL_MAKE_MEM_UNDEFINED((void*)(a), (a)->limit - (PRUword)(a)); \
+        memset((void*)(a), PL_FREE_PATTERN, (a)->limit - (PRUword)(a)); \
+    PR_END_MACRO
 #else
 #define PL_CLEAR_UNUSED(a)
 #define PL_CLEAR_ARENA(a)
 #endif
 
 #define PL_ARENA_RELEASE(pool, mark) \
     PR_BEGIN_MACRO \
         char *_m = (char *)(mark); \
         PLArena *_a = (pool)->current; \
         if (PR_UPTRDIFF(_m, _a->base) <= PR_UPTRDIFF(_a->avail, _a->base)) { \
             _a->avail = (PRUword)PL_ARENA_ALIGN(pool, _m); \
             PL_CLEAR_UNUSED(_a); \
+            PL_MAKE_MEM_NOACCESS((void*)_a->avail, _a->limit - _a->avail); \
             PL_ArenaCountRetract(pool, _m); \
         } else { \
             PL_ArenaRelease(pool, _m); \
         } \
         PL_ArenaCountRelease(pool, _m); \
     PR_END_MACRO
 
 #ifdef PL_ARENAMETER
 #define PL_COUNT_ARENA(pool,op) ((pool)->stats.narenas op)
 #else
@@ skipping 34 matching lines @@
 #define PL_ArenaCountInplaceGrowth(ap, size, incr)      /* nothing */
 #define PL_ArenaCountGrowth(ap, size, incr)             /* nothing */
 #define PL_ArenaCountRelease(ap, mark)                  /* nothing */
 #define PL_ArenaCountRetract(ap, mark)                  /* nothing */
 
 #endif /* !PL_ARENAMETER */
 
 PR_END_EXTERN_C
 
 #endif /* plarena_h___ */