Revert X + X --> X * 2 optz'n which pessimizes heavily on x86.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51474 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 1a87868..655ca4b 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -2292,22 +2292,14 @@
namespace {
-// AddRHS - Implements: X + X --> X << 1 and X + X --> X * 2 for vectors
+// AddRHS - Implements: X + X --> X << 1
struct AddRHS {
Value *RHS;
AddRHS(Value *rhs) : RHS(rhs) {}
bool shouldApply(Value *LHS) const { return LHS == RHS; }
Instruction *apply(BinaryOperator &Add) const {
- if (Add.getType()->getTypeID() == Type::VectorTyID) {
- const VectorType *VTy = cast<VectorType>(Add.getType());
- ConstantInt *CI = ConstantInt::get(VTy->getElementType(), 2);
- std::vector<Constant*> Elts(VTy->getNumElements(), CI);
- return BinaryOperator::CreateMul(Add.getOperand(0),
- ConstantVector::get(Elts));
- } else {
- return BinaryOperator::CreateShl(Add.getOperand(0),
- ConstantInt::get(Add.getType(), 1));
- }
+ return BinaryOperator::CreateShl(Add.getOperand(0),
+ ConstantInt::get(Add.getType(), 1));
}
};
@@ -2635,8 +2627,8 @@
}
}
- // X + X --> X << 1 and X + X --> X * 2 for vectors
- if (I.getType()->isIntOrIntVector() && I.getType() != Type::Int1Ty) {
+ // X + X --> X
+ if (I.getType()->isInteger() && I.getType() != Type::Int1Ty) {
if (Instruction *Result = AssociativeOpt(I, AddRHS(RHS))) return Result;
if (Instruction *RHSI = dyn_cast<Instruction>(RHS)) {