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Remove redunant optimizations from InstCombine, instead call the appropriate functions from SimplifyInstruction 

llvm-svn: 169941
This commit is contained in:
Michael Ilseman 2012-12-12 00:28:32 +00:00
parent bb6f691b01
commit d5787be5ba
2 changed files with 9 additions and 30 deletions
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22
llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
View File

@ -351,18 +351,8 @@ Instruction *InstCombiner::visitFAdd(BinaryOperator &I) {
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
if (Constant *RHSC = dyn_cast<Constant>(RHS)) {
// X + 0 --> X
if (ConstantFP *CFP = dyn_cast<ConstantFP>(RHSC)) {
if (CFP->isExactlyValue(ConstantFP::getNegativeZero
(I.getType())->getValueAPF()))
return ReplaceInstUsesWith(I, LHS);
}
if (isa<PHINode>(LHS))
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
}
if (Value *V = SimplifyFAddInst(LHS, RHS, I.getFastMathFlags(), TD))
return ReplaceInstUsesWith(I, V);
// -A + B --> B - A
// -A + -B --> -(A + B)
@ -374,11 +364,6 @@ Instruction *InstCombiner::visitFAdd(BinaryOperator &I) {
if (Value *V = dyn_castFNegVal(RHS))
return BinaryOperator::CreateFSub(LHS, V);
// Check for X+0.0. Simplify it to X if we know X is not -0.0.
if (ConstantFP *CFP = dyn_cast<ConstantFP>(RHS))
if (CFP->getValueAPF().isPosZero() && CannotBeNegativeZero(LHS))
return ReplaceInstUsesWith(I, LHS);
// Check for (fadd double (sitofp x), y), see if we can merge this into an
// integer add followed by a promotion.
if (SIToFPInst *LHSConv = dyn_cast<SIToFPInst>(LHS)) {
@ -653,6 +638,9 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
Instruction *InstCombiner::visitFSub(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
if (Value *V = SimplifyFSubInst(Op0, Op1, I.getFastMathFlags(), TD))
return ReplaceInstUsesWith(I, V);
// If this is a 'B = x-(-A)', change to B = x+A...
if (Value *V = dyn_castFNegVal(Op1))
return BinaryOperator::CreateFAdd(Op0, V);

17
llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
View File

@ -296,20 +296,11 @@ Instruction *InstCombiner::visitFMul(BinaryOperator &I) {
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
// Simplify mul instructions with a constant RHS.
if (Constant *Op1C = dyn_cast<Constant>(Op1)) {
if (ConstantFP *Op1F = dyn_cast<ConstantFP>(Op1C)) {
// "In IEEE floating point, x*1 is not equivalent to x for nans. However,
// ANSI says we can drop signals, so we can do this anyway." (from GCC)
if (Op1F->isExactlyValue(1.0))
return ReplaceInstUsesWith(I, Op0); // Eliminate 'fmul double %X, 1.0'
} else if (ConstantDataVector *Op1V = dyn_cast<ConstantDataVector>(Op1C)) {
// As above, vector X*splat(1.0) -> X in all defined cases.
if (ConstantFP *F = dyn_cast_or_null<ConstantFP>(Op1V->getSplatValue()))
if (F->isExactlyValue(1.0))
return ReplaceInstUsesWith(I, Op0);
}
if (Value *V = SimplifyFMulInst(Op0, Op1, I.getFastMathFlags(), TD))
return ReplaceInstUsesWith(I, V);
// Simplify mul instructions with a constant RHS.
if (isa<Constant>(Op1)) {
// Try to fold constant mul into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
if (Instruction *R = FoldOpIntoSelect(I, SI))