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[asan] inline PoisonShadow in FakeStack to get ~10% speedup 

llvm-svn: 190660
This commit is contained in:
Kostya Serebryany 2013-09-13 05:57:58 +00:00
parent 21a916b6db
commit 77caab4d7b
1 changed files with 20 additions and 2 deletions
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22
compiler-rt/lib/asan/asan_fake_stack.cc
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@ -17,6 +17,24 @@
namespace __asan {
static const u64 kMagic1 = kAsanStackAfterReturnMagic;
static const u64 kMagic2 = (kMagic1 << 8) | kMagic1;
static const u64 kMagic4 = (kMagic2 << 16) | kMagic2;
static const u64 kMagic8 = (kMagic4 << 32) | kMagic4;
// For small size classes inline PoisonShadow for better performance.
ALWAYS_INLINE void SetShadow(uptr ptr, uptr size, uptr class_id, u64 magic) {
CHECK_EQ(SHADOW_SCALE, 3); // This code expects SHADOW_SCALE=3.
u64 *shadow = reinterpret_cast<u64*>(MemToShadow(ptr));
if (class_id <= 6) {
for (uptr i = 0; i < (1 << class_id); i++)
shadow[i] = magic;
} else {
// The size class is too big, it's cheaper to poison only size bytes.
PoisonShadow(ptr, size, magic);
}
}
void FakeStack::PoisonAll(u8 magic) {
PoisonShadow(reinterpret_cast<uptr>(this), RequiredSize(stack_size_log()),
magic);
@ -111,7 +129,7 @@ ALWAYS_INLINE uptr OnMalloc(uptr class_id, uptr size, uptr real_stack) {
if (!fs) return real_stack;
FakeFrame *ff = fs->Allocate(fs->stack_size_log(), class_id, real_stack);
uptr ptr = reinterpret_cast<uptr>(ff);
PoisonShadow(ptr, size, 0);
SetShadow(ptr, size, class_id, 0);
return ptr;
}
@ -123,7 +141,7 @@ ALWAYS_INLINE void OnFree(uptr ptr, uptr class_id, uptr size, uptr real_stack) {
FakeStack *fs = t->fake_stack();
FakeFrame *ff = reinterpret_cast<FakeFrame *>(ptr);
fs->Deallocate(ff, fs->stack_size_log(), class_id, real_stack);
PoisonShadow(ptr, size, kAsanStackAfterReturnMagic);
SetShadow(ptr, size, class_id, kMagic8);
}
} // namespace __asan