Implement a FIXME: if we're going to insert a cast, we might as well only
insert it once!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12955 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 62247e4..f96cd5d 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -2484,7 +2484,21 @@
if (Constant *C = dyn_cast<Constant>(V))
return ConstantExpr::getCast(C, Ty);
else if (Instruction *I = dyn_cast<Instruction>(V)) {
- // FIXME: check to see if there is already a cast!
+ // Check to see if there is already a cast. If there is, use it.
+ for (Value::use_iterator UI = I->use_begin(), E = I->use_end();
+ UI != E; ++UI) {
+ if ((*UI)->getType() == Ty)
+ if (CastInst *CI = dyn_cast<CastInst>(cast<Instruction>(*UI))) {
+ BasicBlock::iterator It = I; ++It;
+ if (It != BasicBlock::iterator(CI)) {
+ // Splice the cast immediately after the operand in question.
+ I->getParent()->getInstList().splice(It,
+ CI->getParent()->getInstList(),
+ CI);
+ }
+ return CI;
+ }
+ }
BasicBlock::iterator IP = I; ++IP;
if (InvokeInst *II = dyn_cast<InvokeInst>(I))
IP = II->getNormalDest()->begin();