reapply r101364, which has been backed out in r101368

with a fix

rotate CallInst operands, i.e. move callee to the back
of the operand array

the motivation for this patch are laid out in my mail to llvm-commits:
more efficient access to operands and callee, faster callgraph-construction,
smaller compiler binary

llvm-svn: 101397

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
index 836bda36937..e50d0bce8fa 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
@@ -404,7 +404,7 @@ Instruction *InstCombiner::visitLShr(BinaryOperator &I) {
           isPowerOf2_32(BitWidth) && Log2_32(BitWidth) == Op1C->getZExtValue()){
         bool isCtPop = II->getIntrinsicID() == Intrinsic::ctpop;
         Constant *RHS = ConstantInt::getSigned(Op0->getType(), isCtPop ? -1:0);
-        Value *Cmp = Builder->CreateICmpEQ(II->getOperand(1), RHS);
+        Value *Cmp = Builder->CreateICmpEQ(II->getOperand(0), RHS);
         return new ZExtInst(Cmp, II->getType());
       }
     }