Fix a variant of PR6112 found by thinking about it: when doing

RAUW of a global variable with a local variable in function F,
if function local metadata M in function G was using the global
then M would become function-local to both F and G, which is not
allowed.  See the testcase for an example.  Fixed by detecting
this situation and zapping the metadata operand when it occurs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103007 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 12 insertions, 4 deletions

diff --git a/test/Transforms/GlobalOpt/metadata.ll b/test/Transforms/GlobalOpt/metadata.ll
index a09ba72..d5521bf 100644
--- a/test/Transforms/GlobalOpt/metadata.ll
+++ b/test/Transforms/GlobalOpt/metadata.ll
@@ -1,7 +1,8 @@
 ; RUN: opt -S -globalopt < %s | FileCheck %s
 
 ; PR6112 - When globalopt does RAUW(@G, %G), the metadata reference should drop
-; to null.
+; to null.  Function local metadata that references @G from a different function
+; to that containing %G should likewise drop to null.
 @G = internal global i8** null
 
 define i32 @main(i32 %argc, i8** %argv) {
@@ -11,9 +12,16 @@ define i32 @main(i32 %argc, i8** %argv) {
   ret i32 0
 }
 
-!named = !{!0}
+define void @foo(i32 %x) {
+  call void @llvm.dbg.value(metadata !{i8*** @G, i32 %x}, i64 0, metadata !1)
+; CHECK: call void @llvm.dbg.value(metadata !{null, i32 %x}, i64 0, metadata !1)
+  ret void
+}
 
-; CHECK: !0 = metadata !{null}
-!0 = metadata !{i8*** @G}
+declare void @llvm.dbg.value(metadata, i64, metadata) nounwind readnone
 
+!named = !{!0}
 
+!0 = metadata !{i8*** @G}
+; CHECK: !0 = metadata !{null}
+!1 = metadata !{i8* null}