From: Amy Huang <akhuang@google.com>
Date: Wed, 29 May 2019 21:45:34 +0000 (+0000)
Subject: CodeView - add static data members to global variable debug info.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e7fac8a0763b4595c1e8db743697857a93d2bf7d;p=clang

CodeView - add static data members to global variable debug info.

Summary:
Add static data members to IR debug info's list of global variables
so that they are emitted as S_CONSTANT records.

Related to https://bugs.llvm.org/show_bug.cgi?id=41615.

Reviewers: rnk

Subscribers: aprantl, cfe-commits, llvm-commits, thakis

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D62167

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@362038 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index 89c053f4b2..b79169f0a0 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -4361,9 +4361,13 @@ void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD, const APValue &Init) {
     return;
   }
 
-  // Do not emit separate definitions for function local const/statics.
+  llvm::DIScope *DContext = nullptr;
+
+  // Do not emit separate definitions for function local consts.
   if (isa<FunctionDecl>(VD->getDeclContext()))
     return;
+
+  // Emit definition for static members in CodeView.
   VD = cast<ValueDecl>(VD->getCanonicalDecl());
   auto *VarD = cast<VarDecl>(VD);
   if (VarD->isStaticDataMember()) {
@@ -4375,10 +4379,16 @@ void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD, const APValue &Init) {
     // through its scope.
     RetainedTypes.push_back(
         CGM.getContext().getRecordType(RD).getAsOpaquePtr());
-    return;
-  }
 
-  llvm::DIScope *DContext = getDeclContextDescriptor(VD);
+    if (!CGM.getCodeGenOpts().EmitCodeView)
+      return;
+
+    // Use the global scope for static members.
+    DContext = getContextDescriptor(
+        cast<Decl>(CGM.getContext().getTranslationUnitDecl()), TheCU);
+  } else {
+    DContext = getDeclContextDescriptor(VD);
+  }
 
   auto &GV = DeclCache[VD];
   if (GV)
diff --git a/test/CodeGenCXX/debug-info-static-member.cpp b/test/CodeGenCXX/debug-info-static-member.cpp
index 702d1f87e7..8ad86843f4 100644
--- a/test/CodeGenCXX/debug-info-static-member.cpp
+++ b/test/CodeGenCXX/debug-info-static-member.cpp
@@ -1,6 +1,7 @@
 // RUN: %clangxx -target x86_64-unknown-unknown -g %s -emit-llvm -S -o - | FileCheck %s
 // RUN: %clangxx -target x86_64-unknown-unknown -g -std=c++98 %s -emit-llvm -S -o - | FileCheck %s
 // RUN: %clangxx -target x86_64-unknown-unknown -g -std=c++11 %s -emit-llvm -S -o - | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-windows-msvc -gcodeview -debug-info-kind=limited %s -emit-llvm -o - | FileCheck --check-prefix MSVC %s
 // PR14471
 
 // CHECK: @_ZN1C1aE = dso_local global i32 4, align 4, !dbg [[A:![0-9]+]]
@@ -35,6 +36,7 @@ public:
 // CHECK: [[A]] = !DIGlobalVariableExpression(var: [[AV:.*]], expr: !DIExpression())
 // CHECK: [[AV]] = distinct !DIGlobalVariable(name: "a",
 // CHECK-SAME:                                declaration: ![[DECL_A:[0-9]+]])
+// MSVC: distinct !DIGlobalVariable(name: "a"
 //
 // CHECK: !DICompositeType(tag: DW_TAG_enumeration_type, name: "X"{{.*}}, identifier: "_ZTS1X")
 // CHECK: !DICompositeType(tag: DW_TAG_structure_type, name: "anon_static_decl_struct"
@@ -48,6 +50,7 @@ int C::a = 4;
 // CHECK: [[B]] = !DIGlobalVariableExpression(var: [[BV:.*]], expr: !DIExpression())
 // CHECK: [[BV]] = distinct !DIGlobalVariable(name: "b",
 // CHECK-SAME:                                declaration: ![[DECL_B:[0-9]+]])
+// MSVC: distinct !DIGlobalVariable(name: "b"
 // CHECK: ![[DECL_B]] = !DIDerivedType(tag: DW_TAG_member, name: "b"
 // CHECK-NOT:                                 size:
 // CHECK-NOT:                                 align:
@@ -95,6 +98,7 @@ int C::a = 4;
 int C::b = 2;
 // CHECK: [[C]] = !DIGlobalVariableExpression(var: [[CV:.*]], expr: !DIExpression())
 // CHECK: [[CV]] = distinct !DIGlobalVariable(name: "c", {{.*}} declaration: ![[DECL_C]])
+// MSVC: distinct !DIGlobalVariable(name: "c"
 int C::c = 1;
 
 int main()
@@ -114,11 +118,18 @@ struct anon_static_decl_struct {
 };
 }
 
-
 int ref() {
   return anon_static_decl_struct::anon_static_decl_var;
 }
 
+// In MSVC, static data members should be emitted as global variables when used.
+// MSVC: !DIGlobalVariableExpression(var: [[ANON_STATIC_DECL:![0-9]+]],
+// MSVC-SAME: !DIExpression(DW_OP_constu, 117, DW_OP_stack_value)
+// MSVC: [[ANON_STATIC_DECL]] = distinct !DIGlobalVariable(name: "anon_static_decl_var"
+// MSVC: !DIGlobalVariableExpression(var: [[STATIC_DECL_TEMPL:![0-9]+]]
+// MSVC-SAME: !DIExpression(DW_OP_constu, 7, DW_OP_stack_value)
+// MSVC: [[STATIC_DECL_TEMPL]] = distinct !DIGlobalVariable(name: "static_decl_templ_var"
+
 template<typename T>
 struct static_decl_templ {
   static const int static_decl_templ_var = 7;