Rename variables to be consistent (CST -> Cst). No functional change intended.

llvm-svn: 196161
This commit is contained in:
Kay Tiong Khoo 2013-12-02 22:11:56 +00:00
parent 85fdef8bea
commit 14489a85ab

View File

@ -1078,17 +1078,17 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
}
break;
case Instruction::Xor: // (icmp pred (xor X, XorCST), CI)
if (ConstantInt *XorCST = dyn_cast<ConstantInt>(LHSI->getOperand(1))) {
case Instruction::Xor: // (icmp pred (xor X, XorCst), CI)
if (ConstantInt *XorCst = dyn_cast<ConstantInt>(LHSI->getOperand(1))) {
// If this is a comparison that tests the signbit (X < 0) or (x > -1),
// fold the xor.
if ((ICI.getPredicate() == ICmpInst::ICMP_SLT && RHSV == 0) ||
(ICI.getPredicate() == ICmpInst::ICMP_SGT && RHSV.isAllOnesValue())) {
Value *CompareVal = LHSI->getOperand(0);
// If the sign bit of the XorCST is not set, there is no change to
// If the sign bit of the XorCst is not set, there is no change to
// the operation, just stop using the Xor.
if (!XorCST->isNegative()) {
if (!XorCst->isNegative()) {
ICI.setOperand(0, CompareVal);
Worklist.Add(LHSI);
return &ICI;
@ -1110,8 +1110,8 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
if (LHSI->hasOneUse()) {
// (icmp u/s (xor A SignBit), C) -> (icmp s/u A, (xor C SignBit))
if (!ICI.isEquality() && XorCST->getValue().isSignBit()) {
const APInt &SignBit = XorCST->getValue();
if (!ICI.isEquality() && XorCst->getValue().isSignBit()) {
const APInt &SignBit = XorCst->getValue();
ICmpInst::Predicate Pred = ICI.isSigned()
? ICI.getUnsignedPredicate()
: ICI.getSignedPredicate();
@ -1120,8 +1120,8 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
}
// (icmp u/s (xor A ~SignBit), C) -> (icmp s/u (xor C ~SignBit), A)
if (!ICI.isEquality() && XorCST->isMaxValue(true)) {
const APInt &NotSignBit = XorCST->getValue();
if (!ICI.isEquality() && XorCst->isMaxValue(true)) {
const APInt &NotSignBit = XorCst->getValue();
ICmpInst::Predicate Pred = ICI.isSigned()
? ICI.getUnsignedPredicate()
: ICI.getSignedPredicate();
@ -1134,20 +1134,20 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
// (icmp ugt (xor X, C), ~C) -> (icmp ult X, C)
// iff -C is a power of 2
if (ICI.getPredicate() == ICmpInst::ICMP_UGT &&
XorCST->getValue() == ~RHSV && (RHSV + 1).isPowerOf2())
return new ICmpInst(ICmpInst::ICMP_ULT, LHSI->getOperand(0), XorCST);
XorCst->getValue() == ~RHSV && (RHSV + 1).isPowerOf2())
return new ICmpInst(ICmpInst::ICMP_ULT, LHSI->getOperand(0), XorCst);
// (icmp ult (xor X, C), -C) -> (icmp uge X, C)
// iff -C is a power of 2
if (ICI.getPredicate() == ICmpInst::ICMP_ULT &&
XorCST->getValue() == -RHSV && RHSV.isPowerOf2())
return new ICmpInst(ICmpInst::ICMP_UGE, LHSI->getOperand(0), XorCST);
XorCst->getValue() == -RHSV && RHSV.isPowerOf2())
return new ICmpInst(ICmpInst::ICMP_UGE, LHSI->getOperand(0), XorCst);
}
break;
case Instruction::And: // (icmp pred (and X, AndCST), RHS)
case Instruction::And: // (icmp pred (and X, AndCst), RHS)
if (LHSI->hasOneUse() && isa<ConstantInt>(LHSI->getOperand(1)) &&
LHSI->getOperand(0)->hasOneUse()) {
ConstantInt *AndCST = cast<ConstantInt>(LHSI->getOperand(1));
ConstantInt *AndCst = cast<ConstantInt>(LHSI->getOperand(1));
// If the LHS is an AND of a truncating cast, we can widen the
// and/compare to be the input width without changing the value
@ -1158,10 +1158,10 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
// Extending a relational comparison when we're checking the sign
// bit would not work.
if (ICI.isEquality() ||
(!AndCST->isNegative() && RHSV.isNonNegative())) {
(!AndCst->isNegative() && RHSV.isNonNegative())) {
Value *NewAnd =
Builder->CreateAnd(Cast->getOperand(0),
ConstantExpr::getZExt(AndCST, Cast->getSrcTy()));
ConstantExpr::getZExt(AndCst, Cast->getSrcTy()));
NewAnd->takeName(LHSI);
return new ICmpInst(ICI.getPredicate(), NewAnd,
ConstantExpr::getZExt(RHS, Cast->getSrcTy()));
@ -1177,7 +1177,7 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
if (ICI.isEquality() && RHSV.getActiveBits() <= Ty->getBitWidth()) {
Value *NewAnd =
Builder->CreateAnd(Cast->getOperand(0),
ConstantExpr::getTrunc(AndCST, Ty));
ConstantExpr::getTrunc(AndCst, Ty));
NewAnd->takeName(LHSI);
return new ICmpInst(ICI.getPredicate(), NewAnd,
ConstantExpr::getTrunc(RHS, Ty));
@ -1195,7 +1195,7 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
ConstantInt *ShAmt;
ShAmt = Shift ? dyn_cast<ConstantInt>(Shift->getOperand(1)) : 0;
Type *Ty = Shift ? Shift->getType() : 0; // Type of the shift.
Type *AndTy = AndCST->getType(); // Type of the and.
Type *AndTy = AndCst->getType(); // Type of the and.
// We can fold this as long as we can't shift unknown bits
// into the mask. This can happen with signed shift
@ -1215,7 +1215,7 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
uint32_t BitWidth = AndTy->getPrimitiveSizeInBits();
if ((APInt::getHighBitsSet(BitWidth, BitWidth-ShAmtVal) &
AndCST->getValue()) == 0)
AndCst->getValue()) == 0)
CanFold = true;
} else if (ShiftOpcode == Instruction::Shl ||
ShiftOpcode == Instruction::LShr) {
@ -1242,12 +1242,12 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
return ReplaceInstUsesWith(ICI, Builder->getTrue());
} else {
ICI.setOperand(1, NewCst);
Constant *NewAndCST;
Constant *NewAndCst;
if (Shift->getOpcode() == Instruction::Shl)
NewAndCST = ConstantExpr::getLShr(AndCST, ShAmt);
NewAndCst = ConstantExpr::getLShr(AndCst, ShAmt);
else
NewAndCST = ConstantExpr::getShl(AndCST, ShAmt);
LHSI->setOperand(1, NewAndCST);
NewAndCst = ConstantExpr::getShl(AndCst, ShAmt);
LHSI->setOperand(1, NewAndCst);
LHSI->setOperand(0, Shift->getOperand(0));
Worklist.Add(Shift); // Shift is dead.
return &ICI;
@ -1264,10 +1264,10 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
// Compute C << Y.
Value *NS;
if (Shift->getOpcode() == Instruction::LShr) {
NS = Builder->CreateShl(AndCST, Shift->getOperand(1));
NS = Builder->CreateShl(AndCst, Shift->getOperand(1));
} else {
// Insert a logical shift.
NS = Builder->CreateLShr(AndCST, Shift->getOperand(1));
NS = Builder->CreateLShr(AndCst, Shift->getOperand(1));
}
// Compute X & (C << Y).
@ -1278,12 +1278,12 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
return &ICI;
}
// Replace ((X & AndCST) > RHSV) with ((X & AndCST) != 0), if any
// bit set in (X & AndCST) will produce a result greater than RHSV.
// Replace ((X & AndCst) > RHSV) with ((X & AndCst) != 0), if any
// bit set in (X & AndCst) will produce a result greater than RHSV.
if (ICI.getPredicate() == ICmpInst::ICMP_UGT) {
unsigned NTZ = AndCST->getValue().countTrailingZeros();
if ((NTZ < AndCST->getBitWidth()) &&
APInt::getOneBitSet(AndCST->getBitWidth(), NTZ).ugt(RHSV))
unsigned NTZ = AndCst->getValue().countTrailingZeros();
if ((NTZ < AndCst->getBitWidth()) &&
APInt::getOneBitSet(AndCst->getBitWidth(), NTZ).ugt(RHSV))
return new ICmpInst(ICmpInst::ICMP_NE, LHSI,
Constant::getNullValue(RHS->getType()));
}