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

This reverts commit r320499 again to resolve the problem with the
sanitizers bbots.

llvm-svn: 320501

2 files changed, 4 insertions, 51 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
index fbbdfaa04dd..01fc1528681 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
@@ -1339,10 +1339,10 @@ static bool equivalentAddressValues(Value *A, Value *B) {
 /// Converts store (bitcast (load (bitcast (select ...)))) to
 /// store (load (select ...)), where select is minmax:
 /// select ((cmp load V1, load V2), V1, V2).
-static bool removeBitcastsFromLoadStoreOnMinMax(InstCombiner &IC,
-                                                StoreInst &SI) {
+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;
@@ -1354,26 +1354,9 @@ static bool removeBitcastsFromLoadStoreOnMinMax(InstCombiner &IC,
   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 *USI = cast<StoreInst>(UI);
-    IC.Builder.SetInsertPoint(USI);
-    combineStoreToNewValue(IC, *USI, NewLI);
-    if (USI != &SI)
-      IC.eraseInstFromFunction(*cast<Instruction>(UI));
-  }
-  IC.Worklist.Remove(LI);
+  combineStoreToNewValue(IC, SI, NewLI);
   return true;
 }
 
diff --git a/llvm/test/Transforms/InstCombine/multiple-uses-load-bitcast-select.ll b/llvm/test/Transforms/InstCombine/multiple-uses-load-bitcast-select.ll
deleted file mode 100644
index 28509df6d2f..00000000000
--- a/llvm/test/Transforms/InstCombine/multiple-uses-load-bitcast-select.ll
+++ /dev/null
@@ -1,30 +0,0 @@
-; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -instcombine -S -data-layout="E-m:e-i1:8:16-i8:8:16-i64:64-f128:64-v128:64-a:8:16-n32:64" | FileCheck %s
-
-define void @PR35618(i64* %st1, double* %st2) {
-; CHECK-LABEL: @PR35618(
-; CHECK-NEXT:    [[Y1:%.*]] = alloca double, align 8
-; CHECK-NEXT:    [[Z1:%.*]] = alloca double, align 8
-; CHECK-NEXT:    [[LD1:%.*]] = load double, double* [[Y1]], align 8
-; CHECK-NEXT:    [[LD2:%.*]] = load double, double* [[Z1]], align 8
-; CHECK-NEXT:    [[TMP10:%.*]] = fcmp olt double [[LD1]], [[LD2]]
-; CHECK-NEXT:    [[TMP121:%.*]] = select i1 [[TMP10]], double [[LD1]], double [[LD2]]
-; CHECK-NEXT:    [[TMP1:%.*]] = bitcast i64* [[ST1:%.*]] to double*
-; CHECK-NEXT:    store double [[TMP121]], double* [[TMP1]], align 8
-; CHECK-NEXT:    store double [[TMP121]], double* [[ST2:%.*]], align 8
-; CHECK-NEXT:    ret void
-;
-  %y1 = alloca double
-  %z1 = alloca double
-  %ld1 = load double, double* %y1
-  %ld2 = load double, double* %z1
-  %tmp10 = fcmp olt double %ld1, %ld2
-  %sel = select i1 %tmp10, double* %y1, double* %z1
-  %tmp11 = bitcast double* %sel to i64*
-  %tmp12 = load i64, i64* %tmp11
-  store i64 %tmp12, i64* %st1
-  %bc = bitcast double* %st2 to i64*
-  store i64 %tmp12, i64* %bc
-  ret void
-}
-