Emit debug info for global constants whose address is taken exactly once.

Add a check to the DeclCache before emitting debug info for a
GlobalVariable a second time and just attach the previsously created one to it.

<rdar://problem/26721101>

llvm-svn: 286322

1 files changed, 18 insertions, 0 deletions

diff --git a/clang/test/CodeGen/debug-info-global-constant.c b/clang/test/CodeGen/debug-info-global-constant.c
new file mode 100644
index 00000000000..f214fdcd113
--- /dev/null
+++ b/clang/test/CodeGen/debug-info-global-constant.c
@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -emit-llvm -debug-info-kind=standalone \
+// RUN:      -triple %itanium_abi_triple %s -o - | FileCheck %s
+
+// Debug info for a global constant whose address is taken should be emitted
+// exactly once.
+
+// CHECK: @i = internal constant i32 1, align 4, !dbg ![[I:[0-9]+]]
+// CHECK: ![[I]] = distinct !DIGlobalVariable(name: "i",
+// CHECK-SAME:                                expr: ![[EXPR:[0-9]+]]
+// CHECK: !DICompileUnit({{.*}}globals: ![[GLOBALS:[0-9]+]])
+// CHECK: ![[GLOBALS]] = !{![[I]]}
+// CHECK: ![[EXPR]] = !DIExpression(DW_OP_constu, 1, DW_OP_stack_value)
+static const int i = 1;
+
+void g(const int *, int);
+void f() {
+  g(&i, i);
+}