if (!Origin) {
Origin = OpOrigin;
} else {
- Value *FlatShadow = MSV->convertToShadowTyNoVec(OpShadow, IRB);
- Value *Cond = IRB.CreateICmpNE(FlatShadow,
- MSV->getCleanShadow(FlatShadow));
- Origin = IRB.CreateSelect(Cond, OpOrigin, Origin);
+ Constant *ConstOrigin = dyn_cast<Constant>(OpOrigin);
+ // No point in adding something that might result in 0 origin value.
+ if (!ConstOrigin || !ConstOrigin->isNullValue()) {
+ Value *FlatShadow = MSV->convertToShadowTyNoVec(OpShadow, IRB);
+ Value *Cond =
+ IRB.CreateICmpNE(FlatShadow, MSV->getCleanShadow(FlatShadow));
+ Origin = IRB.CreateSelect(Cond, OpOrigin, Origin);
+ }
}
}
return *this;
SC.Done(&I);
}
+ // \brief Handle multiplication by constant.
+ //
+ // Handle a special case of multiplication by constant that may have one or
+ // more zeros in the lower bits. This makes corresponding number of lower bits
+ // of the result zero as well. We model it by shifting the other operand
+ // shadow left by the required number of bits. Effectively, we transform
+ // (X * (A * 2**B)) to ((X << B) * A) and instrument (X << B) as (Sx << B).
+ // We use multiplication by 2**N instead of shift to cover the case of
+ // multiplication by 0, which may occur in some elements of a vector operand.
+ void handleMulByConstant(BinaryOperator &I, Constant *ConstArg,
+ Value *OtherArg) {
+ Constant *ShadowMul;
+ Type *Ty = ConstArg->getType();
+ if (Ty->isVectorTy()) {
+ unsigned NumElements = Ty->getVectorNumElements();
+ Type *EltTy = Ty->getSequentialElementType();
+ SmallVector<Constant *, 16> Elements;
+ for (unsigned Idx = 0; Idx < NumElements; ++Idx) {
+ ConstantInt *Elt =
+ dyn_cast<ConstantInt>(ConstArg->getAggregateElement(Idx));
+ APInt V = Elt->getValue();
+ APInt V2 = APInt(V.getBitWidth(), 1) << V.countTrailingZeros();
+ Elements.push_back(ConstantInt::get(EltTy, V2));
+ }
+ ShadowMul = ConstantVector::get(Elements);
+ } else {
+ ConstantInt *Elt = dyn_cast<ConstantInt>(ConstArg);
+ APInt V = Elt->getValue();
+ APInt V2 = APInt(V.getBitWidth(), 1) << V.countTrailingZeros();
+ ShadowMul = ConstantInt::get(Elt->getType(), V2);
+ }
+
+ IRBuilder<> IRB(&I);
+ setShadow(&I,
+ IRB.CreateMul(getShadow(OtherArg), ShadowMul, "msprop_mul_cst"));
+ setOrigin(&I, getOrigin(OtherArg));
+ }
+
+ void visitMul(BinaryOperator &I) {
+ Constant *constOp0 = dyn_cast<Constant>(I.getOperand(0));
+ Constant *constOp1 = dyn_cast<Constant>(I.getOperand(1));
+ if (constOp0 && !constOp1)
+ handleMulByConstant(I, constOp0, I.getOperand(1));
+ else if (constOp1 && !constOp0)
+ handleMulByConstant(I, constOp1, I.getOperand(0));
+ else
+ handleShadowOr(I);
+ }
+
void visitFAdd(BinaryOperator &I) { handleShadowOr(I); }
void visitFSub(BinaryOperator &I) { handleShadowOr(I); }
void visitFMul(BinaryOperator &I) { handleShadowOr(I); }
void visitAdd(BinaryOperator &I) { handleShadowOr(I); }
void visitSub(BinaryOperator &I) { handleShadowOr(I); }
void visitXor(BinaryOperator &I) { handleShadowOr(I); }
- void visitMul(BinaryOperator &I) { handleShadowOr(I); }
void handleDiv(Instruction &I) {
IRBuilder<> IRB(&I);
setOriginForNaryOp(I);
}
- // \brief Instrument vector shift instrinsic.
+ // \brief Get an X86_MMX-sized vector type.
+ Type *getMMXVectorTy(unsigned EltSizeInBits) {
+ const unsigned X86_MMXSizeInBits = 64;
+ return VectorType::get(IntegerType::get(*MS.C, EltSizeInBits),
+ X86_MMXSizeInBits / EltSizeInBits);
+ }
+
+ // \brief Returns a signed counterpart for an (un)signed-saturate-and-pack
+ // intrinsic.
+ Intrinsic::ID getSignedPackIntrinsic(Intrinsic::ID id) {
+ switch (id) {
+ case llvm::Intrinsic::x86_sse2_packsswb_128:
+ case llvm::Intrinsic::x86_sse2_packuswb_128:
+ return llvm::Intrinsic::x86_sse2_packsswb_128;
+
+ case llvm::Intrinsic::x86_sse2_packssdw_128:
+ case llvm::Intrinsic::x86_sse41_packusdw:
+ return llvm::Intrinsic::x86_sse2_packssdw_128;
+
+ case llvm::Intrinsic::x86_avx2_packsswb:
+ case llvm::Intrinsic::x86_avx2_packuswb:
+ return llvm::Intrinsic::x86_avx2_packsswb;
+
+ case llvm::Intrinsic::x86_avx2_packssdw:
+ case llvm::Intrinsic::x86_avx2_packusdw:
+ return llvm::Intrinsic::x86_avx2_packssdw;
+
+ case llvm::Intrinsic::x86_mmx_packsswb:
+ case llvm::Intrinsic::x86_mmx_packuswb:
+ return llvm::Intrinsic::x86_mmx_packsswb;
+
+ case llvm::Intrinsic::x86_mmx_packssdw:
+ return llvm::Intrinsic::x86_mmx_packssdw;
+ default:
+ llvm_unreachable("unexpected intrinsic id");
+ }
+ }
+
+ // \brief Instrument vector pack instrinsic.
//
// This function instruments intrinsics like x86_mmx_packsswb, that
- // packs elements of 2 input vectors into half as much bits with saturation.
- // Shadow is propagated with the same intrinsic applied to
- // sext(Sa != zeroinitializer), sext(Sb != zeroinitializer).
- void handleVectorPackIntrinsic(IntrinsicInst &I) {
+ // packs elements of 2 input vectors into half as many bits with saturation.
+ // Shadow is propagated with the signed variant of the same intrinsic applied
+ // to sext(Sa != zeroinitializer), sext(Sb != zeroinitializer).
+ // EltSizeInBits is used only for x86mmx arguments.
+ void handleVectorPackIntrinsic(IntrinsicInst &I, unsigned EltSizeInBits = 0) {
assert(I.getNumArgOperands() == 2);
+ bool isX86_MMX = I.getOperand(0)->getType()->isX86_MMXTy();
IRBuilder<> IRB(&I);
Value *S1 = getShadow(&I, 0);
Value *S2 = getShadow(&I, 1);
- Type *T = S1->getType();
+ assert(isX86_MMX || S1->getType()->isVectorTy());
+
+ // SExt and ICmpNE below must apply to individual elements of input vectors.
+ // In case of x86mmx arguments, cast them to appropriate vector types and
+ // back.
+ Type *T = isX86_MMX ? getMMXVectorTy(EltSizeInBits) : S1->getType();
+ if (isX86_MMX) {
+ S1 = IRB.CreateBitCast(S1, T);
+ S2 = IRB.CreateBitCast(S2, T);
+ }
Value *S1_ext = IRB.CreateSExt(
IRB.CreateICmpNE(S1, llvm::Constant::getNullValue(T)), T);
Value *S2_ext = IRB.CreateSExt(
IRB.CreateICmpNE(S2, llvm::Constant::getNullValue(T)), T);
- Value *S = IRB.CreateCall2(I.getCalledValue(), S1_ext, S2_ext,
- "_msprop_vector_pack");
+ if (isX86_MMX) {
+ Type *X86_MMXTy = Type::getX86_MMXTy(*MS.C);
+ S1_ext = IRB.CreateBitCast(S1_ext, X86_MMXTy);
+ S2_ext = IRB.CreateBitCast(S2_ext, X86_MMXTy);
+ }
+
+ Function *ShadowFn = Intrinsic::getDeclaration(
+ F.getParent(), getSignedPackIntrinsic(I.getIntrinsicID()));
+
+ Value *S = IRB.CreateCall2(ShadowFn, S1_ext, S2_ext, "_msprop_vector_pack");
+ if (isX86_MMX) S = IRB.CreateBitCast(S, getShadowTy(&I));
setShadow(&I, S);
setOriginForNaryOp(I);
}
case llvm::Intrinsic::x86_avx2_packssdw:
case llvm::Intrinsic::x86_avx2_packuswb:
case llvm::Intrinsic::x86_avx2_packusdw:
+ handleVectorPackIntrinsic(I);
+ break;
+
case llvm::Intrinsic::x86_mmx_packsswb:
- case llvm::Intrinsic::x86_mmx_packssdw:
case llvm::Intrinsic::x86_mmx_packuswb:
- handleVectorPackIntrinsic(I);
+ handleVectorPackIntrinsic(I, 16);
+ break;
+
+ case llvm::Intrinsic::x86_mmx_packssdw:
+ handleVectorPackIntrinsic(I, 32);
break;
default: