performance: get rid of repeated dereferencing of use_iterator by caching its result
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100550 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/ScalarReplAggregates.cpp b/lib/Transforms/Scalar/ScalarReplAggregates.cpp
index 6211beb..061042a 100644
--- a/lib/Transforms/Scalar/ScalarReplAggregates.cpp
+++ b/lib/Transforms/Scalar/ScalarReplAggregates.cpp
@@ -1702,18 +1702,20 @@
static bool isOnlyCopiedFromConstantGlobal(Value *V, Instruction *&TheCopy,
bool isOffset) {
for (Value::use_iterator UI = V->use_begin(), E = V->use_end(); UI!=E; ++UI) {
- if (LoadInst *LI = dyn_cast<LoadInst>(*UI))
+ User *U = cast<Instruction>(*UI);
+
+ if (LoadInst *LI = dyn_cast<LoadInst>(U))
// Ignore non-volatile loads, they are always ok.
if (!LI->isVolatile())
continue;
- if (BitCastInst *BCI = dyn_cast<BitCastInst>(*UI)) {
+ if (BitCastInst *BCI = dyn_cast<BitCastInst>(U)) {
// If uses of the bitcast are ok, we are ok.
if (!isOnlyCopiedFromConstantGlobal(BCI, TheCopy, isOffset))
return false;
continue;
}
- if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(*UI)) {
+ if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(U)) {
// If the GEP has all zero indices, it doesn't offset the pointer. If it
// doesn't, it does.
if (!isOnlyCopiedFromConstantGlobal(GEP, TheCopy,
@@ -1724,7 +1726,7 @@
// If this is isn't our memcpy/memmove, reject it as something we can't
// handle.
- if (!isa<MemTransferInst>(*UI))
+ if (!isa<MemTransferInst>(U))
return false;
// If we already have seen a copy, reject the second one.
@@ -1737,7 +1739,7 @@
// If the memintrinsic isn't using the alloca as the dest, reject it.
if (UI.getOperandNo() != 1) return false;
- MemIntrinsic *MI = cast<MemIntrinsic>(*UI);
+ MemIntrinsic *MI = cast<MemIntrinsic>(U);
// If the source of the memcpy/move is not a constant global, reject it.
if (!PointsToConstantGlobal(MI->getOperand(2)))