[PATCH] D29996: [DeadStoreElimination] Check function modref behavior before considering memory clobbered

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This revision was automatically updated to reflect the committed changes.
Closed by commit rL296625: [DeadStoreElimination] Check function modref behavior before considering memory… (authored by igor.laevsky).

Changed prior to commit:
  https://reviews.llvm.org/D29996?vs=88565&id=90177#toc

Repository:
  rL LLVM

https://reviews.llvm.org/D29996

Files:
  llvm/trunk/lib/Transforms/Scalar/DeadStoreElimination.cpp
  llvm/trunk/test/Transforms/DeadStoreElimination/operand-bundles.ll


Index: llvm/trunk/test/Transforms/DeadStoreElimination/operand-bundles.ll
===================================================================
--- llvm/trunk/test/Transforms/DeadStoreElimination/operand-bundles.ll
+++ llvm/trunk/test/Transforms/DeadStoreElimination/operand-bundles.ll
@@ -41,3 +41,15 @@
   store i64 0, i64* %s
   ret void
 }
+
+declare noalias i8* @calloc(i64, i64)
+
+define void @test4() {
+; CHECK-LABEL: @test4
+  %local_obj = call i8* @calloc(i64 1, i64 4)
+  call void @foo() ["deopt" (i8* %local_obj)]
+  store i8 0, i8* %local_obj, align 4
+  ; CHECK-NOT: store i8 0, i8* %local_obj, align 4
+  call void @bar(i8* nocapture %local_obj)
+  ret void
+}
Index: llvm/trunk/lib/Transforms/Scalar/DeadStoreElimination.cpp
===================================================================
--- llvm/trunk/lib/Transforms/Scalar/DeadStoreElimination.cpp
+++ llvm/trunk/lib/Transforms/Scalar/DeadStoreElimination.cpp
@@ -551,7 +551,7 @@
       Instruction *I = &*BI;
       if (I->mayWriteToMemory() && I != SecondI) {
         auto Res = AA->getModRefInfo(I, MemLoc);
-        if (Res != MRI_NoModRef)
+        if (Res & MRI_Mod)
           return false;
       }
     }


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