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Commit 1d9d6451 by James Price
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Insert __msan_unposion for masked/scattered stores

Fixes more MSan LLVM JIT false positives. Change-Id: I0579e2cc71b089424fe168cc60fed63c4b431f91 Bug: b/140204746 Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/44708 Presubmit-Ready: James Price <jrprice@google.com> Reviewed-by: 's avatarNicolas Capens <nicolascapens@google.com> Kokoro-Result: kokoro <noreply+kokoro@google.com> Tested-by: 's avatarJames Price <jrprice@google.com>
parent 60727de1
Showing with 62 additions and 4 deletions
src/Reactor/LLVMReactor.cpp
......@@ -459,10 +459,39 @@ void createScatter(llvm::Value *base, llvm::Value *val, llvm::Value *offsets, ll
auto i8Base = jit->builder->CreatePointerCast(base, i8PtrTy);
auto i8Ptrs = jit->builder->CreateGEP(i8Base, offsets);
auto elPtrs = jit->builder->CreatePointerCast(i8Ptrs, elPtrVecTy);
auto i8Mask = jit->builder->CreateIntCast(mask, ::llvm::VectorType::get(i1Ty, numEls), false); // vec<int, int, ...> -> vec<bool, bool, ...>
auto i1Mask = jit->builder->CreateIntCast(mask, ::llvm::VectorType::get(i1Ty, numEls), false); // vec<int, int, ...> -> vec<bool, bool, ...>
auto align = ::llvm::ConstantInt::get(i32Ty, alignment);
auto func = ::llvm::Intrinsic::getDeclaration(jit->module.get(), llvm::Intrinsic::masked_scatter, { elVecTy, elPtrVecTy });
jit->builder->CreateCall(func, { val, elPtrs, align, i8Mask });
jit->builder->CreateCall(func, { val, elPtrs, align, i1Mask });
#if __has_feature(memory_sanitizer)
// Mark memory writes as initialized by calling __msan_unpoison
{
// void __msan_unpoison(const volatile void *a, size_t size)
auto voidTy = ::llvm::Type::getVoidTy(jit->context);
auto voidPtrTy = voidTy->getPointerTo();
auto sizetTy = ::llvm::IntegerType::get(jit->context, sizeof(size_t) * 8);
auto funcTy = ::llvm::FunctionType::get(voidTy, { voidPtrTy, sizetTy }, false);
auto func = jit->module->getOrInsertFunction("__msan_unpoison", funcTy);
auto size = jit->module->getDataLayout().getTypeStoreSize(elTy);
for(unsigned i = 0; i < numEls; i++)
{
// Check mask for this element
auto idx = ::llvm::ConstantInt::get(i32Ty, i);
auto thenBlock = ::llvm::BasicBlock::Create(jit->context, "", jit->function);
auto mergeBlock = ::llvm::BasicBlock::Create(jit->context, "", jit->function);
jit->builder->CreateCondBr(jit->builder->CreateExtractElement(i1Mask, idx), thenBlock, mergeBlock);
jit->builder->SetInsertPoint(thenBlock);
// Insert __msan_unpoison call in conditional block
auto elPtr = jit->builder->CreateExtractElement(elPtrs, idx);
jit->builder->CreateCall(func, { jit->builder->CreatePointerCast(elPtr, voidPtrTy),
::llvm::ConstantInt::get(sizetTy, size) });
jit->builder->CreateBr(mergeBlock);
jit->builder->SetInsertPoint(mergeBlock);
}
}
#endif
}
} // namespace
......@@ -1165,10 +1194,39 @@ void Nucleus::createMaskedStore(Value *ptr, Value *val, Value *mask, unsigned in
auto i32Ty = ::llvm::Type::getInt32Ty(jit->context);
auto elVecTy = V(val)->getType();
auto elVecPtrTy = elVecTy->getPointerTo();
auto i8Mask = jit->builder->CreateIntCast(V(mask), ::llvm::VectorType::get(i1Ty, numEls), false); // vec<int, int, ...> -> vec<bool, bool, ...>
auto i1Mask = jit->builder->CreateIntCast(V(mask), ::llvm::VectorType::get(i1Ty, numEls), false); // vec<int, int, ...> -> vec<bool, bool, ...>
auto align = ::llvm::ConstantInt::get(i32Ty, alignment);
auto func = ::llvm::Intrinsic::getDeclaration(jit->module.get(), llvm::Intrinsic::masked_store, { elVecTy, elVecPtrTy });
jit->builder->CreateCall(func, { V(val), V(ptr), align, i8Mask });
jit->builder->CreateCall(func, { V(val), V(ptr), align, i1Mask });
#if __has_feature(memory_sanitizer)
// Mark memory writes as initialized by calling __msan_unpoison
{
// void __msan_unpoison(const volatile void *a, size_t size)
auto voidTy = ::llvm::Type::getVoidTy(jit->context);
auto voidPtrTy = voidTy->getPointerTo();
auto sizetTy = ::llvm::IntegerType::get(jit->context, sizeof(size_t) * 8);
auto funcTy = ::llvm::FunctionType::get(voidTy, { voidPtrTy, sizetTy }, false);
auto func = jit->module->getOrInsertFunction("__msan_unpoison", funcTy);
auto size = jit->module->getDataLayout().getTypeStoreSize(llvm::cast<llvm::VectorType>(elVecTy)->getElementType());
for(unsigned i = 0; i < numEls; i++)
{
// Check mask for this element
auto idx = ::llvm::ConstantInt::get(i32Ty, i);
auto thenBlock = ::llvm::BasicBlock::Create(jit->context, "", jit->function);
auto mergeBlock = ::llvm::BasicBlock::Create(jit->context, "", jit->function);
jit->builder->CreateCondBr(jit->builder->CreateExtractElement(i1Mask, idx), thenBlock, mergeBlock);
jit->builder->SetInsertPoint(thenBlock);
// Insert __msan_unpoison call in conditional block
auto elPtr = jit->builder->CreateGEP(V(ptr), idx);
jit->builder->CreateCall(func, { jit->builder->CreatePointerCast(elPtr, voidPtrTy),
::llvm::ConstantInt::get(sizetTy, size) });
jit->builder->CreateBr(mergeBlock);
jit->builder->SetInsertPoint(mergeBlock);
}
}
#endif
}
RValue<Float4> Gather(RValue<Pointer<Float>> base, RValue<Int4> offsets, RValue<Int4> mask, unsigned int alignment, bool zeroMaskedLanes /* = false */)
......
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