[clang] Unwrap CountAttributed for debug info (PR #86017)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-clang-codegen

@llvm/pr-subscribers-clang

Author: Yeoul Na (rapidsna)

<details>
<summary>Changes</summary>

Fix crash caused by 3eb9ff30959a670559bcba03d149d4c51bf7c9c9

---
Full diff: https://github.com/llvm/llvm-project/pull/86017.diff


2 Files Affected:

- (modified) clang/lib/CodeGen/CGDebugInfo.cpp (+3) 
- (added) clang/test/CodeGen/attr-counted-by-debug-info.c (+18) 


``````````diff
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 07ecaa81c47d84..7453ed14aef414 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -3463,6 +3463,9 @@ static QualType UnwrapTypeForDebugInfo(QualType T, const ASTContext &C) {
     case Type::BTFTagAttributed:
       T = cast<BTFTagAttributedType>(T)->getWrappedType();
       break;
+    case Type::CountAttributed:
+      T = cast<CountAttributedType>(T)->desugar();
+      break;
     case Type::Elaborated:
       T = cast<ElaboratedType>(T)->getNamedType();
       break;
diff --git a/clang/test/CodeGen/attr-counted-by-debug-info.c b/clang/test/CodeGen/attr-counted-by-debug-info.c
new file mode 100644
index 00000000000000..f3e7897e12d667
--- /dev/null
+++ b/clang/test/CodeGen/attr-counted-by-debug-info.c
@@ -0,0 +1,18 @@
+// RUN: %clang -emit-llvm -DCOUNTED_BY -S -g %s -o - | FileCheck %s
+// RUN: %clang -emit-llvm -S -g %s -o - | FileCheck %s
+
+#ifdef COUNTED_BY
+#define __counted_by(member)    __attribute__((__counted_by__(member)))
+#else
+#define __counted_by(member)
+#endif
+
+struct {
+  int num_counters;
+  long value[] __counted_by(num_counters);
+} agent_send_response_port_num;
+
+// CHECK: !DICompositeType(tag: DW_TAG_array_type, baseType: ![[BT:.*]], elements: ![[ELEMENTS:.*]])
+// ![[BT]] = !DIBasicType(name: "long", size: 64, encoding: DW_ATE_signed)
+// ![[ELEMENTS]] = !{![[COUNT]]}
+// ![[COUNT]] = !DISubrange(count: -1)
\ No newline at end of file

``````````

</details>


https://github.com/llvm/llvm-project/pull/86017