commit 3314a104c61be44ae45a9cad839d096e8c6b05ef
author Nick Lewycky <nicholas@mxc.ca> Fri Jul 11 08:16:26 2008 +0000
committer Nick Lewycky <nicholas@mxc.ca> Fri Jul 11 08:16:26 2008 +0000
tree ff57cc2fe727883edce2e13171bffb42499a24b0
parent e98bef9ef4d3eaefce668a638b1974d7dfae4d8d

Document 'mask' in this calculation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53454 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Scalar/InstructionCombining.cpp

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 3152510..5864a62 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -5498,6 +5498,7 @@
         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(