From: Evan Cheng <evan.cheng@apple.com>
Date: Wed, 22 Apr 2009 23:09:16 +0000 (+0000)
Subject: A few more places where the check of use_empty is needed.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a8d4d7fe47460313e6aaf5cbb73d4bc892202988;p=oota-llvm.git

A few more places where the check of use_empty is needed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69842 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/IndVarSimplify.cpp b/lib/Transforms/Scalar/IndVarSimplify.cpp
index b1cde4177bf..1dd84b1816b 100644
--- a/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ b/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -739,6 +739,7 @@ bool IndVarSimplify::runOnLoop(Loop *L, LPPassManager &LPM) {
         // See if we can figure out sext(i+constant) doesn't wrap, so we can
         // use a larger add.  This is common in subscripting.
         if (UInst && UInst->getOpcode()==Instruction::Add &&
+            !UInst->use_empty() &&
             allUsesAreSameTyped(Instruction::SExt, UInst) &&
             isa<ConstantInt>(UInst->getOperand(1)) &&
             NoSignedWrap && LimitVal) {
@@ -771,6 +772,7 @@ bool IndVarSimplify::runOnLoop(Loop *L, LPPassManager &LPM) {
         // Try for sext(i | constant).  This is safe as long as the
         // high bit of the constant is not set.
         if (UInst && UInst->getOpcode()==Instruction::Or &&
+            !UInst->use_empty() &&
             allUsesAreSameTyped(Instruction::SExt, UInst) && NoSignedWrap &&
             isa<ConstantInt>(UInst->getOperand(1))) {
           ConstantInt* RHS = dyn_cast<ConstantInt>(UInst->getOperand(1));
@@ -841,6 +843,7 @@ bool IndVarSimplify::runOnLoop(Loop *L, LPPassManager &LPM) {
           ConstantInt* AddRHS = dyn_cast<ConstantInt>(UInst->getOperand(1));
           Instruction *UInst2 = dyn_cast<Instruction>(UInst->use_begin());
           if (UInst2 && UInst2->getOpcode() == Instruction::And &&
+              !UInst2->use_empty() &&
               allUsesAreSameTyped(Instruction::ZExt, UInst2) &&
               isa<ConstantInt>(UInst2->getOperand(1))) {
             ZExtInst* oldZext = dyn_cast<ZExtInst>(UInst2->use_begin());