Re-apply the infamous r108614, with a fix pointed out by Dirk Steinke.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110036 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson 2010-08-02 09:32:13 +00:00
parent 82fe467ca5
commit 61378363b7
2 changed files with 64 additions and 5 deletions

View File

@ -472,6 +472,22 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
Value *NewOr = Builder->CreateOr(Val, Val2);
return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
}
// (icmp ne (A & C1), 0) & (icmp ne (A & C2), 0) -->
// (icmp eq (A & (C1|C2)), (C1|C2)) where C1 and C2 are non-zero POT
if (LHSCC == ICmpInst::ICMP_NE && LHSCst->isZero()) {
Value *Op1 = 0, *Op2 = 0;
ConstantInt *CI1 = 0, *CI2 = 0;
if (match(LHS->getOperand(0), m_And(m_Value(Op1), m_ConstantInt(CI1))) &&
match(RHS->getOperand(0), m_And(m_Value(Op2), m_ConstantInt(CI2)))) {
if (Op1 == Op2 && !CI1->isZero() && !CI2->isZero() &&
CI1->getValue().isPowerOf2() && CI2->getValue().isPowerOf2()) {
Constant *ConstOr = ConstantExpr::getOr(CI1, CI2);
Value *NewAnd = Builder->CreateAnd(Op1, ConstOr);
return Builder->CreateICmp(ICmpInst::ICMP_EQ, NewAnd, ConstOr);
}
}
}
}
// From here on, we only handle:
@ -1151,11 +1167,28 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
if (LHSCst == 0 || RHSCst == 0) return 0;
// (icmp ne A, 0) | (icmp ne B, 0) --> (icmp ne (A|B), 0)
if (LHSCst == RHSCst && LHSCC == RHSCC &&
LHSCC == ICmpInst::ICMP_NE && LHSCst->isZero()) {
Value *NewOr = Builder->CreateOr(Val, Val2);
return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
if (LHSCst == RHSCst && LHSCC == RHSCC) {
// (icmp ne A, 0) | (icmp ne B, 0) --> (icmp ne (A|B), 0)
if (LHSCC == ICmpInst::ICMP_NE && LHSCst->isZero()) {
Value *NewOr = Builder->CreateOr(Val, Val2);
return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
}
// (icmp eq (A & C1), 0) | (icmp eq (A & C2), 0) -->
// (icmp ne (A & (C1|C2)), (C1|C2)) where C1 and C2 are non-zero POT
if (LHSCC == ICmpInst::ICMP_EQ && LHSCst->isZero()) {
Value *Op1 = 0, *Op2 = 0;
ConstantInt *CI1 = 0, *CI2 = 0;
if (match(LHS->getOperand(0), m_And(m_Value(Op1), m_ConstantInt(CI1))) &&
match(RHS->getOperand(0), m_And(m_Value(Op2), m_ConstantInt(CI2)))) {
if (Op1 == Op2 && !CI1->isZero() && !CI2->isZero() &&
CI1->getValue().isPowerOf2() && CI2->getValue().isPowerOf2()) {
Constant *ConstOr = ConstantExpr::getOr(CI1, CI2);
Value *NewAnd = Builder->CreateAnd(Op1, ConstOr);
return Builder->CreateICmp(ICmpInst::ICMP_NE, NewAnd, ConstOr);
}
}
}
}
// From here on, we only handle:

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@ -0,0 +1,26 @@
; This test makes sure that these instructions are properly eliminated.
;
; RUN: opt < %s -instcombine -S | \
; RUN: not grep {tobool}
; END.
define i32 @main(i32 %argc, i8** %argv) nounwind ssp {
entry:
%and = and i32 %argc, 1 ; <i32> [#uses=1]
%tobool = icmp ne i32 %and, 0 ; <i1> [#uses=1]
%and2 = and i32 %argc, 2 ; <i32> [#uses=1]
%tobool3 = icmp ne i32 %and2, 0 ; <i1> [#uses=1]
%or.cond = and i1 %tobool, %tobool3 ; <i1> [#uses=1]
%retval.0 = select i1 %or.cond, i32 2, i32 1 ; <i32> [#uses=1]
ret i32 %retval.0
}
define i32 @main2(i32 %argc, i8** nocapture %argv) nounwind readnone ssp {
entry:
%and = and i32 %argc, 1 ; <i32> [#uses=1]
%tobool = icmp eq i32 %and, 0 ; <i1> [#uses=1]
%and2 = and i32 %argc, 2 ; <i32> [#uses=1]
%tobool3 = icmp eq i32 %and2, 0 ; <i1> [#uses=1]
%or.cond = or i1 %tobool, %tobool3 ; <i1> [#uses=1]
%storemerge = select i1 %or.cond, i32 0, i32 1 ; <i32> [#uses=1]
ret i32 %storemerge
}