[llvm-commits] [llvm] r108429 - in /llvm/trunk/lib/Transforms/InstCombine: InstCombineAndOrXor.cpp InstCombineSelect.cpp
Owen Anderson
resistor at mac.com
Thu Jul 15 10:24:23 PDT 2010
Author: resistor
Date: Thu Jul 15 12:24:23 2010
New Revision: 108429
URL: http://llvm.org/viewvc/llvm-project?rev=108429&view=rev
Log:
Per Chris' suggestion, get rid of the select canonicalization and just add
the corresponding or-icmp-and pattern. This has the added benefit of doing
the matching earlier, and thus being less susceptible to being confused by
earlier transforms.
Modified:
llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
llvm/trunk/lib/Transforms/InstCombine/InstCombineSelect.cpp
Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp?rev=108429&r1=108428&r2=108429&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp Thu Jul 15 12:24:23 2010
@@ -1177,6 +1177,25 @@
return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
}
+ // (icmp eq (A & C1), 0) | (icmp eq (A & C2), 0) -->
+ // (icmp ne (A & (C1|C2)), (C1|C2))
+ if (LHSCC == ICmpInst::ICMP_EQ && LHSCst->isZero()) {
+ Instruction *I1 = dyn_cast<Instruction>(Val);
+ Instruction *I2 = dyn_cast<Instruction>(Val2);
+ if (I1 && I1->getOpcode() == Instruction::And &&
+ I2 && I2->getOpcode() == Instruction::And &&
+ I1->getOperand(0) == I1->getOperand(0)) {
+ ConstantInt *CI1 = dyn_cast<ConstantInt>(I1->getOperand(1));
+ ConstantInt *CI2 = dyn_cast<ConstantInt>(I2->getOperand(1));
+ if (CI1 && !CI1->isZero() && CI2 && !CI2->isZero() &&
+ CI1->getValue().operator&(CI2->getValue()) == 0) {
+ Constant *ConstOr = ConstantExpr::getOr(CI1, CI2);
+ Value *NewAnd = Builder->CreateAnd(I1->getOperand(0), ConstOr);
+ return Builder->CreateICmp(ICmpInst::ICMP_NE, NewAnd, ConstOr);
+ }
+ }
+ }
+
// From here on, we only handle:
// (icmp1 A, C1) | (icmp2 A, C2) --> something simpler.
if (Val != Val2) return 0;
Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineSelect.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineSelect.cpp?rev=108429&r1=108428&r2=108429&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineSelect.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineSelect.cpp Thu Jul 15 12:24:23 2010
@@ -699,34 +699,6 @@
SI.setOperand(2, TrueVal);
return &SI;
}
-
- // select (A == 0 | B == 0), T, F--> select (A != 0 & B != 0), F, T
- // Note: This is a canonicalization rather than an optimization, and is used
- // to expose opportunities to other instcombine transforms.
- Instruction* CondInst = dyn_cast<Instruction>(CondVal);
- if (CondInst && CondInst->hasOneUse() &&
- CondInst->getOpcode() == Instruction::Or) {
- ICmpInst *LHSCmp = dyn_cast<ICmpInst>(CondInst->getOperand(0));
- ICmpInst *RHSCmp = dyn_cast<ICmpInst>(CondInst->getOperand(1));
- if (LHSCmp && LHSCmp->hasOneUse() &&
- LHSCmp->getPredicate() == ICmpInst::ICMP_EQ &&
- RHSCmp && RHSCmp->hasOneUse() &&
- RHSCmp->getPredicate() == ICmpInst::ICMP_EQ) {
- ConstantInt* C1 = dyn_cast<ConstantInt>(LHSCmp->getOperand(1));
- ConstantInt* C2 = dyn_cast<ConstantInt>(RHSCmp->getOperand(1));
- if (C1 && C1->isZero() && C2 && C2->isZero()) {
- LHSCmp->setPredicate(ICmpInst::ICMP_NE);
- RHSCmp->setPredicate(ICmpInst::ICMP_NE);
- Value *And =
- InsertNewInstBefore(BinaryOperator::CreateAnd(LHSCmp, RHSCmp,
- "and."+CondVal->getName()), SI);
- SI.setOperand(0, And);
- SI.setOperand(1, FalseVal);
- SI.setOperand(2, TrueVal);
- return &SI;
- }
- }
- }
return 0;
}
More information about the llvm-commits
mailing list