Revert "[InstCombine] Fix PR35618: Instcombine hangs on single minmax load bitcast."

This reverts commit r320488 because of the failed asan buildbots..

llvm-svn: 320490

1 files changed, 4 insertions, 20 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
index 27adcade8f1..01fc1528681 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
@@ -1341,7 +1341,8 @@ static bool equivalentAddressValues(Value *A, Value *B) {
 /// select ((cmp load V1, load V2), V1, V2).
 bool removeBitcastsFromLoadStoreOnMinMax(InstCombiner &IC, StoreInst &SI) {
   // bitcast?
-  if (!match(SI.getPointerOperand(), m_BitCast(m_Value())))
+  Value *StoreAddr;
+  if (!match(SI.getPointerOperand(), m_BitCast(m_Value(StoreAddr))))
     return false;
   // load? integer?
   Value *LoadAddr;
@@ -1353,26 +1354,9 @@ bool removeBitcastsFromLoadStoreOnMinMax(InstCombiner &IC, StoreInst &SI) {
   if (!isMinMaxWithLoads(LoadAddr))
     return false;
 
-  if (!all_of(LI->users(), [LI, LoadAddr](User *U) {
-        auto *SI = dyn_cast<StoreInst>(U);
-        return SI && SI->getPointerOperand() != LI &&
-               peekThroughBitcast(SI->getPointerOperand()) != LoadAddr &&
-               !SI->getPointerOperand()->isSwiftError();
-      }))
-    return false;
-
-  IC.Builder.SetInsertPoint(LI);
   LoadInst *NewLI = combineLoadToNewType(
       IC, *LI, LoadAddr->getType()->getPointerElementType());
-  // Replace all the stores with stores of the newly loaded value.
-  for (auto *UI : LI->users()) {
-    auto *SI = cast<StoreInst>(UI);
-    IC.Builder.SetInsertPoint(SI);
-    combineStoreToNewValue(IC, *SI, NewLI);
-    IC.eraseInstFromFunction(*SI);
-  }
-  IC.replaceInstUsesWith(*LI, UndefValue::get(LI->getType()));
-  IC.eraseInstFromFunction(*LI);
+  combineStoreToNewValue(IC, SI, NewLI);
   return true;
 }
 
@@ -1401,7 +1385,7 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) {
     return eraseInstFromFunction(SI);
 
   if (removeBitcastsFromLoadStoreOnMinMax(*this, SI))
-    return nullptr;
+    return eraseInstFromFunction(SI);
 
   // Replace GEP indices if possible.
   if (Instruction *NewGEPI = replaceGEPIdxWithZero(*this, Ptr, SI)) {