Document 'mask' in this calculation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53454 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nick Lewycky 2008-07-11 08:16:26 +00:00
parent 569d8f7087
commit 7d9843fc37

View File

@ -5498,6 +5498,7 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) {
case Instruction::Mul:
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op0I->getOperand(1))) {
// a * Cst icmp eq/ne b * Cst --> a & Mask icmp b & Mask
// Mask = -1 >> count-trailing-zeros(Cst).
if (!CI->isZero() && !CI->isOne()) {
const APInt &AP = CI->getValue();
ConstantInt *Mask = ConstantInt::get(