Handle "if ((x|y) != 0)" for ints like we do for bools. Fixes missed

optimization opportunity pointed out by Chris Lattner.

llvm-svn: 31118
This commit is contained in:
Nick Lewycky 2006-10-22 21:36:41 +00:00
parent 76dd3bb34a
commit 2c734f3fc1
2 changed files with 34 additions and 10 deletions

View File

@ -334,32 +334,35 @@ namespace {
if (V1 == ConstantBool::getFalse())
add(Opcode, BO->getOperand(0), BO->getOperand(1), true);
break;
case Instruction::And:
if (V1 == ConstantBool::getTrue()) {
case Instruction::And: {
ConstantIntegral *CI = dyn_cast<ConstantIntegral>(V1);
if (CI && CI->isAllOnesValue()) {
add(Opcode, V1, BO->getOperand(0), false);
add(Opcode, V1, BO->getOperand(1), false);
}
break;
case Instruction::Or:
if (V1 == ConstantBool::getFalse()) {
} break;
case Instruction::Or: {
ConstantIntegral *CI = dyn_cast<ConstantIntegral>(V1);
if (CI && CI->isNullValue()) {
add(Opcode, V1, BO->getOperand(0), false);
add(Opcode, V1, BO->getOperand(1), false);
}
break;
case Instruction::Xor:
if (V1 == ConstantBool::getTrue()) {
} break;
case Instruction::Xor: {
ConstantIntegral *CI = dyn_cast<ConstantIntegral>(V1);
if (CI->isAllOnesValue()) {
if (BO->getOperand(0) == V1)
add(Opcode, ConstantBool::getFalse(), BO->getOperand(1), false);
if (BO->getOperand(1) == V1)
add(Opcode, ConstantBool::getFalse(), BO->getOperand(0), false);
}
if (V1 == ConstantBool::getFalse()) {
if (CI->isNullValue()) {
if (BO->getOperand(0) == ConstantBool::getTrue())
add(Opcode, ConstantBool::getTrue(), BO->getOperand(1), false);
if (BO->getOperand(1) == ConstantBool::getTrue())
add(Opcode, ConstantBool::getTrue(), BO->getOperand(0), false);
}
break;
} break;
default:
break;
}

View File

@ -0,0 +1,21 @@
; RUN: llvm-as < %s | opt -predsimplify -instcombine -simplifycfg | llvm-dis | grep -v declare | not grep fail
int %f(int %x, int %y) {
entry:
%tmp2 = or int %x, %y ; <int> [#uses=1]
%tmp = setne int %tmp2, 0 ; <bool> [#uses=1]
br bool %tmp, label %cond_true, label %return
cond_true: ; preds = %entry
%tmp4 = seteq int %x, 0 ; <bool> [#uses=1]
br bool %tmp4, label %cond_true5, label %return
cond_true5: ; preds = %cond_true
%tmp6 = call int %fail( ) ; <int> [#uses=0]
ret int %tmp6
return: ; preds = %cond_next7
ret int 0
}
declare int %fail()