diff --git a/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp b/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
--- a/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
+++ b/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
@@ -1579,8 +1579,14 @@
     // Treat byval or inalloca arguments the same as Allocas, stores to them are
     // dead at the end of the function.
     for (Argument &AI : F.args())
-      if (AI.hasPassPointeeByValueAttr())
-        State.InvisibleToCallerBeforeRet.insert(&AI);
+      if (AI.hasPassPointeeByValueAttr()) {
+        // Pointers marked as byval cannot be accessed even if the function
+        // exits through an exception.
+        if (AI.hasByValAttr())
+          State.InvisibleToCallerBeforeRet.insert(&AI);
+        State.InvisibleToCallerAfterRet.insert(&AI);
+      }
+
     return State;
   }
 
diff --git a/llvm/test/Transforms/DeadStoreElimination/MSSA/simple-todo.ll b/llvm/test/Transforms/DeadStoreElimination/MSSA/simple-todo.ll
--- a/llvm/test/Transforms/DeadStoreElimination/MSSA/simple-todo.ll
+++ b/llvm/test/Transforms/DeadStoreElimination/MSSA/simple-todo.ll
@@ -10,37 +10,6 @@
 declare void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32) nounwind
 declare void @llvm.init.trampoline(i8*, i8*, i8*)
 
-; Test for byval handling.
-%struct.x = type { i32, i32, i32, i32 }
-define void @test9(%struct.x* byval  %a) nounwind  {
-; CHECK-LABEL: @test9(
-; CHECK-NEXT:    ret void
-;
-  %tmp2 = getelementptr %struct.x, %struct.x* %a, i32 0, i32 0
-  store i32 1, i32* %tmp2, align 4
-  ret void
-}
-
-; Test for inalloca handling.
-define void @test9_2(%struct.x* inalloca  %a) nounwind  {
-; CHECK-LABEL: @test9_2(
-; CHECK-NEXT:    ret void
-;
-  %tmp2 = getelementptr %struct.x, %struct.x* %a, i32 0, i32 0
-  store i32 1, i32* %tmp2, align 4
-  ret void
-}
-
-; Test for preallocated handling.
-define void @test9_3(%struct.x* preallocated(%struct.x)  %a) nounwind  {
-; CHECK-LABEL: @test9_3(
-; CHECK-NEXT:    ret void
-;
-  %tmp2 = getelementptr %struct.x, %struct.x* %a, i32 0, i32 0
-  store i32 1, i32* %tmp2, align 4
-  ret void
-}
-
 ; DSE should delete the dead trampoline.
 declare void @test11f()
 define void @test11() {
@@ -57,17 +26,6 @@
 declare noalias i8* @malloc(i32)
 declare noalias i8* @calloc(i32, i32)
 
-define void @test22(i1 %i, i32 %k, i32 %m) nounwind {
-; CHECK-LABEL: @test22(
-; CHECK-NEXT:    ret void
-;
-  %k.addr = alloca i32
-  %m.addr = alloca i32
-  %k.addr.m.addr = select i1 %i, i32* %k.addr, i32* %m.addr
-  store i32 0, i32* %k.addr.m.addr, align 4
-  ret void
-}
-
 declare void @unknown_func()
 
 ; Remove redundant store if loaded value is in another block inside a loop.
diff --git a/llvm/test/Transforms/DeadStoreElimination/MSSA/simple.ll b/llvm/test/Transforms/DeadStoreElimination/MSSA/simple.ll
--- a/llvm/test/Transforms/DeadStoreElimination/MSSA/simple.ll
+++ b/llvm/test/Transforms/DeadStoreElimination/MSSA/simple.ll
@@ -23,6 +23,7 @@
 ; PR8677
 @g = global i32 1
 
+
 define i32 @test3(i32* %g_addr) nounwind {
 ; CHECK-LABEL: @test3(
 ; CHECK-NEXT:    [[G_VALUE:%.*]] = load i32, i32* [[G_ADDR:%.*]], align 4
@@ -136,6 +137,37 @@
 
 }
 
+; Test for byval handling.
+%struct.x = type { i32, i32, i32, i32 }
+define void @test9(%struct.x* byval  %a) nounwind  {
+; CHECK-LABEL: @test9(
+; CHECK-NEXT:    ret void
+;
+  %tmp2 = getelementptr %struct.x, %struct.x* %a, i32 0, i32 0
+  store i32 1, i32* %tmp2, align 4
+  ret void
+}
+
+; Test for inalloca handling.
+define void @test9_2(%struct.x* inalloca  %a) nounwind  {
+; CHECK-LABEL: @test9_2(
+; CHECK-NEXT:    ret void
+;
+  %tmp2 = getelementptr %struct.x, %struct.x* %a, i32 0, i32 0
+  store i32 1, i32* %tmp2, align 4
+  ret void
+}
+
+; Test for preallocated handling.
+define void @test9_3(%struct.x* preallocated(%struct.x)  %a) nounwind  {
+; CHECK-LABEL: @test9_3(
+; CHECK-NEXT:    ret void
+;
+  %tmp2 = getelementptr %struct.x, %struct.x* %a, i32 0, i32 0
+  store i32 1, i32* %tmp2, align 4
+  ret void
+}
+
 ; va_arg has fuzzy dependence, the store shouldn't be zapped.
 define double @test10(i8* %X) {
 ; CHECK-LABEL: @test10(
@@ -223,6 +255,17 @@
   ret void
 }
 
+define void @test22(i1 %i, i32 %k, i32 %m) nounwind {
+; CHECK-LABEL: @test22(
+; CHECK-NEXT:    ret void
+;
+  %k.addr = alloca i32
+  %m.addr = alloca i32
+  %k.addr.m.addr = select i1 %i, i32* %k.addr, i32* %m.addr
+  store i32 0, i32* %k.addr.m.addr, align 4
+  ret void
+}
+
 ; The store here is not dead because the byval call reads it.
 declare void @test19f({i32}* byval align 4 %P)