cache result of operator*

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108146 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/IPO/ArgumentPromotion.cpp b/lib/Transforms/IPO/ArgumentPromotion.cpp
index 89f213e2ac367d43d454bca7ea6905761c6e5a26..28ea079abd360af1791a63875c768919abf6da97 100644 (file)
--- a/lib/Transforms/IPO/ArgumentPromotion.cpp
+++ b/lib/Transforms/IPO/ArgumentPromotion.cpp
@@ -360,19 +360,20 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const {
   IndicesVector Operands;
   for (Value::use_iterator UI = Arg->use_begin(), E = Arg->use_end();
        UI != E; ++UI) {
+    User *U = *UI;
     Operands.clear();
-    if (LoadInst *LI = dyn_cast<LoadInst>(*UI)) {
+    if (LoadInst *LI = dyn_cast<LoadInst>(U)) {
       if (LI->isVolatile()) return false;  // Don't hack volatile loads
       Loads.push_back(LI);
       // Direct loads are equivalent to a GEP with a zero index and then a load.
       Operands.push_back(0);
-    } else if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(*UI)) {
+    } else if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(U)) {
       if (GEP->use_empty()) {
         // Dead GEP's cause trouble later.  Just remove them if we run into
         // them.
         getAnalysis<AliasAnalysis>().deleteValue(GEP);
         GEP->eraseFromParent();
-        // TODO: This runs the above loop over and over again for dead GEPS
+        // TODO: This runs the above loop over and over again for dead GEPs
         // Couldn't we just do increment the UI iterator earlier and erase the
         // use?
         return isSafeToPromoteArgument(Arg, isByVal);
@@ -452,12 +453,14 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const {
     // Now check every path from the entry block to the load for transparency.
     // To do this, we perform a depth first search on the inverse CFG from the
     // loading block.
-    for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
+    for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
+      BasicBlock *P = *PI;
       for (idf_ext_iterator<BasicBlock*, SmallPtrSet<BasicBlock*, 16> >
-             I = idf_ext_begin(*PI, TranspBlocks),
-             E = idf_ext_end(*PI, TranspBlocks); I != E; ++I)
+             I = idf_ext_begin(P, TranspBlocks),
+             E = idf_ext_end(P, TranspBlocks); I != E; ++I)
         if (AA.canBasicBlockModify(**I, Arg, LoadSize))
           return false;
+    }
   }
 
   // If the path from the entry of the function to each load is free of