commit 0a230e0d985625a3909cb78fd867a3abaf434565
author Benjamin Kramer <benny.kra@googlemail.com> Thu Jul 11 16:05:50 2013 +0000
committer Benjamin Kramer <benny.kra@googlemail.com> Thu Jul 11 16:05:50 2013 +0000
tree 5781d89cdddab939dca31f5f5a62c2a1f825b22f
parent 1b3e3eef1fb51ace32b32e5ca217dacb03333b13

Don't use a potentially expensive shift if all we want is one set bit.

No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186095 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/InstCombine/InstCombineAddSub.cpp

diff --git a/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/lib/Transforms/InstCombine/InstCombineAddSub.cpp
index ac7eac9..03fd35f 100644
--- a/lib/Transforms/InstCombine/InstCombineAddSub.cpp
+++ b/lib/Transforms/InstCombine/InstCombineAddSub.cpp
@@ -876,7 +876,7 @@
       uint32_t BitWidth = cast<IntegerType>(V->getType())->getBitWidth();
       uint32_t CSTVal = CST->getLimitedValue(BitWidth);
       CST = ConstantInt::get(V->getType()->getContext(),
-                             APInt(BitWidth, 1).shl(CSTVal));
+                             APInt::getOneBitSet(BitWidth, CSTVal));
       return I->getOperand(0);
     }
   return 0;