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Differential D23708

[asan] Fix size of shadow incorrectly calculated in r279178
ClosedPublic

Authored by vitalybuka on Aug 19 2016, 1:41 AM.

Details

Reviewers
eugenis
Commits
rGb81960a6c858: [asan] Fix size of shadow incorrectly calculated in r279178
rL279222: [asan] Fix size of shadow incorrectly calculated in r279178
Summary

r279178 generates 8 times more stores than necessary.

Diff Detail

Repository
rL LLVM

Event Timeline

vitalybuka updated this revision to Diff 68658.Aug 19 2016, 1:41 AM
vitalybuka retitled this revision from to [asan] Fix size of shadow incorrectly calculated in r279178.
vitalybuka updated this object.
vitalybuka added a reviewer: eugenis.
vitalybuka added a subscriber: llvm-commits.
Closed by commit rL279222: [asan] Fix size of shadow incorrectly calculated in r279178 (authored by vitalybuka). · Explain WhyAug 19 2016, 1:41 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
llvm/
trunk/
lib/
Transforms/
Instrumentation/
6 lines
test/
Instrumentation/
AddressSanitizer/
1 line

Diff 68659

llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp

Show First 20 Lines • Show All 2,231 Lines • ▼ Show 20 Lines if (DoStackMalloc) {
Value *Cmp = Value *Cmp =
IRBRet.CreateICmpNE(FakeStack, Constant::getNullValue(IntptrTy)); IRBRet.CreateICmpNE(FakeStack, Constant::getNullValue(IntptrTy));
TerminatorInst *ThenTerm, *ElseTerm; TerminatorInst *ThenTerm, *ElseTerm;
SplitBlockAndInsertIfThenElse(Cmp, Ret, &ThenTerm, &ElseTerm); SplitBlockAndInsertIfThenElse(Cmp, Ret, &ThenTerm, &ElseTerm);
IRBuilder<> IRBPoison(ThenTerm); IRBuilder<> IRBPoison(ThenTerm);
if (StackMallocIdx <= 4) { if (StackMallocIdx <= 4) {
int ClassSize = kMinStackMallocSize << StackMallocIdx; int ClassSize = kMinStackMallocSize << StackMallocIdx;
if ((int)ShadowBytesAfterReturn.size() != ClassSize) { ShadowBytesAfterReturn.resize(ClassSize >> Mapping.Scale,
ShadowBytesAfterReturn.resize(ClassSize,
kAsanStackUseAfterReturnMagic); kAsanStackUseAfterReturnMagic);
}
poisonRedZones(ShadowBytesAfterReturn, IRBPoison, ShadowBase, true); poisonRedZones(ShadowBytesAfterReturn, IRBPoison, ShadowBase, true);
Value *SavedFlagPtrPtr = IRBPoison.CreateAdd( Value *SavedFlagPtrPtr = IRBPoison.CreateAdd(
FakeStack, FakeStack,
ConstantInt::get(IntptrTy, ClassSize - ASan.LongSize / 8)); ConstantInt::get(IntptrTy, ClassSize - ASan.LongSize / 8));
Value *SavedFlagPtr = IRBPoison.CreateLoad( Value *SavedFlagPtr = IRBPoison.CreateLoad(
IRBPoison.CreateIntToPtr(SavedFlagPtrPtr, IntptrPtrTy)); IRBPoison.CreateIntToPtr(SavedFlagPtrPtr, IntptrPtrTy));
IRBPoison.CreateStore( IRBPoison.CreateStore(
Constant::getNullValue(IRBPoison.getInt8Ty()), Constant::getNullValue(IRBPoison.getInt8Ty()),
▲ Show 20 Lines • Show All 149 Lines • Show Last 20 Lines

llvm/trunk/test/Instrumentation/AddressSanitizer/stack-poisoning.ll

Show All 38 Lines; Then Block: poison the entire frame.
; CHECK-UAR: store i64 -723401728380766731 ; CHECK-UAR: store i64 -723401728380766731
; CHECK-UAR: store i64 -723401728380766731 ; CHECK-UAR: store i64 -723401728380766731
; CHECK-UAR: store i64 -723401728380766731 ; CHECK-UAR: store i64 -723401728380766731
; CHECK-UAR: store i64 -723401728380766731 ; CHECK-UAR: store i64 -723401728380766731
; CHECK-UAR: store i64 -723401728380766731 ; CHECK-UAR: store i64 -723401728380766731
; CHECK-UAR: store i64 -723401728380766731 ; CHECK-UAR: store i64 -723401728380766731
; CHECK-UAR: store i64 -723401728380766731 ; CHECK-UAR: store i64 -723401728380766731
; CHECK-UAR: store i64 -723401728380766731 ; CHECK-UAR: store i64 -723401728380766731
; CHECK-UAR-NOT: store i64
; CHECK-UAR: store i8 0 ; CHECK-UAR: store i8 0
; CHECK-UAR-NOT: store ; CHECK-UAR-NOT: store
; CHECK-UAR: label ; CHECK-UAR: label
; Else Block: no UAR frame. Only unpoison the redzones. ; Else Block: no UAR frame. Only unpoison the redzones.
; CHECK-UAR: store i64 0 ; CHECK-UAR: store i64 0
; CHECK-UAR: store i64 0 ; CHECK-UAR: store i64 0
; CHECK-UAR: store i32 0 ; CHECK-UAR: store i32 0
; CHECK-UAR: store i64 0 ; CHECK-UAR: store i64 0
Show All 20 Lines