Daily bump.
[official-gcc.git] / libsanitizer / sanitizer_common / sanitizer_allocator.cc
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1 //===-- sanitizer_allocator.cc --------------------------------------------===//
2 //
3 // This file is distributed under the University of Illinois Open Source
4 // License. See LICENSE.TXT for details.
5 //
6 //===----------------------------------------------------------------------===//
7 //
8 // This file is shared between AddressSanitizer and ThreadSanitizer
9 // run-time libraries.
10 // This allocator is used inside run-times.
11 //===----------------------------------------------------------------------===//
12 #include "sanitizer_allocator.h"
13 #include "sanitizer_allocator_internal.h"
14 #include "sanitizer_common.h"
15 #include "sanitizer_flags.h"
17 namespace __sanitizer {
19 // ThreadSanitizer for Go uses libc malloc/free.
20 #if defined(SANITIZER_GO) || defined(SANITIZER_USE_MALLOC)
21 # if SANITIZER_LINUX && !SANITIZER_ANDROID
22 extern "C" void *__libc_malloc(uptr size);
23 extern "C" void __libc_free(void *ptr);
24 # define LIBC_MALLOC __libc_malloc
25 # define LIBC_FREE __libc_free
26 # else
27 # include <stdlib.h>
28 # define LIBC_MALLOC malloc
29 # define LIBC_FREE free
30 # endif
32 static void *RawInternalAlloc(uptr size, InternalAllocatorCache *cache) {
33 (void)cache;
34 return LIBC_MALLOC(size);
37 static void RawInternalFree(void *ptr, InternalAllocatorCache *cache) {
38 (void)cache;
39 LIBC_FREE(ptr);
42 InternalAllocator *internal_allocator() {
43 return 0;
46 #else // SANITIZER_GO
48 static ALIGNED(64) char internal_alloc_placeholder[sizeof(InternalAllocator)];
49 static atomic_uint8_t internal_allocator_initialized;
50 static StaticSpinMutex internal_alloc_init_mu;
52 static InternalAllocatorCache internal_allocator_cache;
53 static StaticSpinMutex internal_allocator_cache_mu;
55 InternalAllocator *internal_allocator() {
56 InternalAllocator *internal_allocator_instance =
57 reinterpret_cast<InternalAllocator *>(&internal_alloc_placeholder);
58 if (atomic_load(&internal_allocator_initialized, memory_order_acquire) == 0) {
59 SpinMutexLock l(&internal_alloc_init_mu);
60 if (atomic_load(&internal_allocator_initialized, memory_order_relaxed) ==
61 0) {
62 internal_allocator_instance->Init();
63 atomic_store(&internal_allocator_initialized, 1, memory_order_release);
66 return internal_allocator_instance;
69 static void *RawInternalAlloc(uptr size, InternalAllocatorCache *cache) {
70 if (cache == 0) {
71 SpinMutexLock l(&internal_allocator_cache_mu);
72 return internal_allocator()->Allocate(&internal_allocator_cache, size, 8,
73 false);
75 return internal_allocator()->Allocate(cache, size, 8, false);
78 static void RawInternalFree(void *ptr, InternalAllocatorCache *cache) {
79 if (cache == 0) {
80 SpinMutexLock l(&internal_allocator_cache_mu);
81 return internal_allocator()->Deallocate(&internal_allocator_cache, ptr);
83 internal_allocator()->Deallocate(cache, ptr);
86 #endif // SANITIZER_GO
88 const u64 kBlockMagic = 0x6A6CB03ABCEBC041ull;
90 void *InternalAlloc(uptr size, InternalAllocatorCache *cache) {
91 if (size + sizeof(u64) < size)
92 return 0;
93 void *p = RawInternalAlloc(size + sizeof(u64), cache);
94 if (p == 0)
95 return 0;
96 ((u64*)p)[0] = kBlockMagic;
97 return (char*)p + sizeof(u64);
100 void InternalFree(void *addr, InternalAllocatorCache *cache) {
101 if (addr == 0)
102 return;
103 addr = (char*)addr - sizeof(u64);
104 CHECK_EQ(kBlockMagic, ((u64*)addr)[0]);
105 ((u64*)addr)[0] = 0;
106 RawInternalFree(addr, cache);
109 // LowLevelAllocator
110 static LowLevelAllocateCallback low_level_alloc_callback;
112 void *LowLevelAllocator::Allocate(uptr size) {
113 // Align allocation size.
114 size = RoundUpTo(size, 8);
115 if (allocated_end_ - allocated_current_ < (sptr)size) {
116 uptr size_to_allocate = Max(size, GetPageSizeCached());
117 allocated_current_ =
118 (char*)MmapOrDie(size_to_allocate, __func__);
119 allocated_end_ = allocated_current_ + size_to_allocate;
120 if (low_level_alloc_callback) {
121 low_level_alloc_callback((uptr)allocated_current_,
122 size_to_allocate);
125 CHECK(allocated_end_ - allocated_current_ >= (sptr)size);
126 void *res = allocated_current_;
127 allocated_current_ += size;
128 return res;
131 void SetLowLevelAllocateCallback(LowLevelAllocateCallback callback) {
132 low_level_alloc_callback = callback;
135 bool CallocShouldReturnNullDueToOverflow(uptr size, uptr n) {
136 if (!size) return false;
137 uptr max = (uptr)-1L;
138 return (max / size) < n;
141 void *AllocatorReturnNull() {
142 if (common_flags()->allocator_may_return_null)
143 return 0;
144 Report("%s's allocator is terminating the process instead of returning 0\n",
145 SanitizerToolName);
146 Report("If you don't like this behavior set allocator_may_return_null=1\n");
147 CHECK(0);
148 return 0;
151 } // namespace __sanitizer