[llvm-commits] [llvm] r125265 - in /llvm/trunk: lib/Transforms/InstCombine/InstCombineAndOrXor.cpp test/Transforms/InstCombine/sub.ll
Chris Lattner
sabre at nondot.org
Wed Feb 9 21:17:27 PST 2011
Author: lattner
Date: Wed Feb 9 23:17:27 2011
New Revision: 125265
URL: http://llvm.org/viewvc/llvm-project?rev=125265&view=rev
Log:
more cleanups, notably bitcast isn't used for "signed to unsigned type
conversions". :)
Modified:
llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
llvm/trunk/test/Transforms/InstCombine/sub.ll
Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp?rev=125265&r1=125264&r2=125265&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp Wed Feb 9 23:17:27 2011
@@ -703,9 +703,9 @@
// whole construct
if (!MCst->isZero())
return 0;
- Value* newOr1 = Builder->CreateOr(B, D);
- Value* newOr2 = ConstantExpr::getOr(CCst, ECst);
- Value* newAnd = Builder->CreateAnd(A, newOr1);
+ Value *newOr1 = Builder->CreateOr(B, D);
+ Value *newOr2 = ConstantExpr::getOr(CCst, ECst);
+ Value *newAnd = Builder->CreateAnd(A, newOr1);
return Builder->CreateICmp(NEWCC, newAnd, newOr2);
}
return 0;
@@ -729,12 +729,9 @@
}
}
- {
- // handle (roughly):
- // (icmp eq (A & B), C) & (icmp eq (A & D), E)
- Value* fold = foldLogOpOfMaskedICmps(LHS, RHS, ICmpInst::ICMP_EQ, Builder);
- if (fold) return fold;
- }
+ // handle (roughly): (icmp eq (A & B), C) & (icmp eq (A & D), E)
+ if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, ICmpInst::ICMP_EQ, Builder))
+ return V;
// This only handles icmp of constants: (icmp1 A, C1) & (icmp2 B, C2).
Value *Val = LHS->getOperand(0), *Val2 = RHS->getOperand(0);
@@ -997,7 +994,6 @@
if (ConstantInt *AndRHS = dyn_cast<ConstantInt>(Op1)) {
const APInt &AndRHSMask = AndRHS->getValue();
- APInt NotAndRHS(~AndRHSMask);
// Optimize a variety of ((val OP C1) & C2) combinations...
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0)) {
@@ -1006,10 +1002,11 @@
switch (Op0I->getOpcode()) {
default: break;
case Instruction::Xor:
- case Instruction::Or:
+ case Instruction::Or: {
// If the mask is only needed on one incoming arm, push it up.
if (!Op0I->hasOneUse()) break;
+ APInt NotAndRHS(~AndRHSMask);
if (MaskedValueIsZero(Op0LHS, NotAndRHS)) {
// Not masking anything out for the LHS, move to RHS.
Value *NewRHS = Builder->CreateAnd(Op0RHS, AndRHS,
@@ -1025,6 +1022,7 @@
}
break;
+ }
case Instruction::Add:
// ((A & N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == AndRHS.
// ((A | N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == 0
@@ -1044,14 +1042,12 @@
// (A - N) & AndRHS -> -N & AndRHS iff A&AndRHS==0 and AndRHS
// has 1's for all bits that the subtraction with A might affect.
- if (Op0I->hasOneUse()) {
+ if (Op0I->hasOneUse() && !match(Op0LHS, m_Zero())) {
uint32_t BitWidth = AndRHSMask.getBitWidth();
uint32_t Zeros = AndRHSMask.countLeadingZeros();
APInt Mask = APInt::getLowBitsSet(BitWidth, BitWidth - Zeros);
- ConstantInt *A = dyn_cast<ConstantInt>(Op0LHS);
- if (!(A && A->isZero()) && // avoid infinite recursion.
- MaskedValueIsZero(Op0LHS, Mask)) {
+ if (MaskedValueIsZero(Op0LHS, Mask)) {
Value *NewNeg = Builder->CreateNeg(Op0RHS);
return BinaryOperator::CreateAnd(NewNeg, AndRHS);
}
@@ -1073,35 +1069,21 @@
if (ConstantInt *Op0CI = dyn_cast<ConstantInt>(Op0I->getOperand(1)))
if (Instruction *Res = OptAndOp(Op0I, Op0CI, AndRHS, I))
return Res;
- } else if (CastInst *CI = dyn_cast<CastInst>(Op0)) {
- // If this is an integer truncation or change from signed-to-unsigned, and
- // if the source is an and/or with immediate, transform it. This
- // frequently occurs for bitfield accesses.
- if (Instruction *CastOp = dyn_cast<Instruction>(CI->getOperand(0))) {
- if ((isa<TruncInst>(CI) || isa<BitCastInst>(CI)) &&
- CastOp->getNumOperands() == 2)
- if (ConstantInt *AndCI =dyn_cast<ConstantInt>(CastOp->getOperand(1))){
- if (CastOp->getOpcode() == Instruction::And) {
- // Change: and (cast (and X, C1) to T), C2
- // into : and (cast X to T), trunc_or_bitcast(C1)&C2
- // This will fold the two constants together, which may allow
- // other simplifications.
- Value *NewCast = Builder->CreateTruncOrBitCast(
- CastOp->getOperand(0), I.getType(),
- CastOp->getName()+".shrunk");
- // trunc_or_bitcast(C1)&C2
- Constant *C3 = ConstantExpr::getTruncOrBitCast(AndCI,I.getType());
- C3 = ConstantExpr::getAnd(C3, AndRHS);
- return BinaryOperator::CreateAnd(NewCast, C3);
- } else if (CastOp->getOpcode() == Instruction::Or) {
- // Change: and (cast (or X, C1) to T), C2
- // into : trunc(C1)&C2 iff trunc(C1)&C2 == C2
- Constant *C3 = ConstantExpr::getTruncOrBitCast(AndCI,I.getType());
- if (ConstantExpr::getAnd(C3, AndRHS) == AndRHS)
- // trunc(C1)&C2
- return ReplaceInstUsesWith(I, AndRHS);
- }
- }
+ }
+
+ // If this is an integer truncation, and if the source is an 'and' with
+ // immediate, transform it. This frequently occurs for bitfield accesses.
+ {
+ Value *X = 0; ConstantInt *YC = 0;
+ if (match(Op0, m_Trunc(m_And(m_Value(X), m_ConstantInt(YC))))) {
+ // Change: and (trunc (and X, YC) to T), C2
+ // into : and (trunc X to T), trunc(YC) & C2
+ // This will fold the two constants together, which may allow
+ // other simplifications.
+ Value *NewCast = Builder->CreateTrunc(X, I.getType(), "and.shrunk");
+ Constant *C3 = ConstantExpr::getTrunc(YC, I.getType());
+ C3 = ConstantExpr::getAnd(C3, AndRHS);
+ return BinaryOperator::CreateAnd(NewCast, C3);
}
}
@@ -1123,7 +1105,7 @@
I.getName()+".demorgan");
return BinaryOperator::CreateNot(Or);
}
-
+
{
Value *A = 0, *B = 0, *C = 0, *D = 0;
// (A|B) & ~(A&B) -> A^B
Modified: llvm/trunk/test/Transforms/InstCombine/sub.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/sub.ll?rev=125265&r1=125264&r2=125265&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/sub.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/sub.ll Wed Feb 9 23:17:27 2011
@@ -40,7 +40,7 @@
%E = sub i32 %A, %D
ret i32 %E
; CHECK: @test5
-; CHECK: %D = sub i32 %C, %B
+; CHECK: %D1 = sub i32 %C, %B
; CHECK: %E = add
; CHECK: ret i32 %E
}
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