Change greater than to greater than or equal so that an identical sized store to...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161857 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Scalar/DeadStoreElimination.cpp b/lib/Transforms/Scalar/DeadStoreElimination.cpp
index dcae458606e9d9241258c494ff83a83b7004ece0..8b1283ff2531ce3f5ee4d41987169fc9b943b210 100644 (file)
--- a/lib/Transforms/Scalar/DeadStoreElimination.cpp
+++ b/lib/Transforms/Scalar/DeadStoreElimination.cpp
@@ -378,7 +378,7 @@ static OverwriteResult isOverwrite(const AliasAnalysis::Location &Later,
   //
   // We have to be careful here as *Off is signed while *.Size is unsigned.
   if (EarlierOff >= LaterOff &&
-      Later.Size > Earlier.Size &&
+      Later.Size >= Earlier.Size &&
       uint64_t(EarlierOff - LaterOff) + Earlier.Size <= Later.Size)
     return OverwriteComplete;
 

diff --git a/test/Transforms/DeadStoreElimination/simple.ll b/test/Transforms/DeadStoreElimination/simple.ll
index ed53ab7e6071e38615fa67574dbf172694f4e2fd..7a8cdd531b55b851d55ad85da804361971d238cc 100644 (file)
--- a/test/Transforms/DeadStoreElimination/simple.ll
+++ b/test/Transforms/DeadStoreElimination/simple.ll
@@ -291,3 +291,22 @@ define noalias i8* @test23() nounwind uwtable ssp {
   %call = call i8* @strdup(i8* %arrayidx) nounwind
   ret i8* %call
 }
+
+; Make sure same sized store to later element is deleted
+; CHECK: @test24
+; CHECK-NOT: store i32 0
+; CHECK-NOT: store i32 0
+; CHECK: store i32 %b
+; CHECK: store i32 %c
+; CHECK: ret void
+define void @test24([2 x i32]* %a, i32 %b, i32 %c) nounwind {
+  %1 = getelementptr inbounds [2 x i32]* %a, i64 0, i64 0
+  store i32 0, i32* %1, align 4
+  %2 = getelementptr inbounds [2 x i32]* %a, i64 0, i64 1
+  store i32 0, i32* %2, align 4
+  %3 = getelementptr inbounds [2 x i32]* %a, i64 0, i64 0
+  store i32 %b, i32* %3, align 4
+  %4 = getelementptr inbounds [2 x i32]* %a, i64 0, i64 1
+  store i32 %c, i32* %4, align 4
+  ret void
+}