Constant propagating byval pointer is safe if function is readonly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82700 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 18 insertions, 2 deletions

diff --git a/test/Transforms/IPConstantProp/2009-09-24-byval-ptr.ll b/test/Transforms/IPConstantProp/2009-09-24-byval-ptr.ll
index 75055d4..f4bab35 100644
--- a/test/Transforms/IPConstantProp/2009-09-24-byval-ptr.ll
+++ b/test/Transforms/IPConstantProp/2009-09-24-byval-ptr.ll
@@ -16,9 +16,25 @@ entry:
 return:                                           ; preds = %entry
   ret void
 }
-define void @unions() nounwind {
+
+define internal i32 @vfu2(%struct.MYstr* byval align 4 %u) nounwind readonly {
+entry:
+  %0 = getelementptr %struct.MYstr* %u, i32 0, i32 1 ; <i32*> [#uses=1]
+  %1 = load i32* %0
+; CHECK: load i32* getelementptr inbounds (%struct.MYstr* @mystr, i32 0, i32 1) ; <i32> [#uses=1]
+  %2 = getelementptr %struct.MYstr* %u, i32 0, i32 0 ; <i8*> [#uses=1]
+  %3 = load i8* %2
+; CHECK: load i8* getelementptr inbounds (%struct.MYstr* @mystr, i32 0, i32 0) ; <i8> [#uses=1]
+  %4 = zext i8 %3 to i32
+  %5 = add i32 %4, %1
+  ret i32 %5
+}
+
+define i32 @unions() nounwind {
 entry:
   call void @vfu1(%struct.MYstr* byval align 4 @mystr) nounwind
-  ret void
+  %result = call i32 @vfu2(%struct.MYstr* byval align 4 @mystr) nounwind
+
+  ret i32 %result
 }