DebugInfo: Add support for 'nodebug' attribute on typedefs and alias templates
Seems like a logical extension to me - and of interest because it might
help reduce the debug info size of libc++ by applying this attribute to
type traits that have a disproportionate debug info cost compared to the
benefit (& possibly harm/confusion) they cause users.
llvm-svn: 362856
diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
index c20a565..9e2d5c6 100644
--- a/clang/include/clang/Basic/Attr.td
+++ b/clang/include/clang/Basic/Attr.td
@@ -1434,7 +1434,7 @@
def NoDebug : InheritableAttr {
let Spellings = [GCC<"nodebug">];
- let Subjects = SubjectList<[FunctionLike, ObjCMethod, NonParmVar]>;
+ let Subjects = SubjectList<[TypedefName, FunctionLike, ObjCMethod, NonParmVar]>;
let Documentation = [NoDebugDocs];
}
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index a297025..549056d 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -1091,15 +1091,18 @@
assert(Ty->isTypeAlias());
llvm::DIType *Src = getOrCreateType(Ty->getAliasedType(), Unit);
+ auto *AliasDecl =
+ cast<TypeAliasTemplateDecl>(Ty->getTemplateName().getAsTemplateDecl())
+ ->getTemplatedDecl();
+
+ if (AliasDecl->hasAttr<NoDebugAttr>())
+ return Src;
+
SmallString<128> NS;
llvm::raw_svector_ostream OS(NS);
Ty->getTemplateName().print(OS, getPrintingPolicy(), /*qualified*/ false);
printTemplateArgumentList(OS, Ty->template_arguments(), getPrintingPolicy());
- auto *AliasDecl =
- cast<TypeAliasTemplateDecl>(Ty->getTemplateName().getAsTemplateDecl())
- ->getTemplatedDecl();
-
SourceLocation Loc = AliasDecl->getLocation();
return DBuilder.createTypedef(Src, OS.str(), getOrCreateFile(Loc),
getLineNumber(Loc),
@@ -1108,15 +1111,20 @@
llvm::DIType *CGDebugInfo::CreateType(const TypedefType *Ty,
llvm::DIFile *Unit) {
+ llvm::DIType *Underlying =
+ getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit);
+
+ if (Ty->getDecl()->hasAttr<NoDebugAttr>())
+ return Underlying;
+
// We don't set size information, but do specify where the typedef was
// declared.
SourceLocation Loc = Ty->getDecl()->getLocation();
// Typedefs are derived from some other type.
- return DBuilder.createTypedef(
- getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit),
- Ty->getDecl()->getName(), getOrCreateFile(Loc), getLineNumber(Loc),
- getDeclContextDescriptor(Ty->getDecl()));
+ return DBuilder.createTypedef(Underlying, Ty->getDecl()->getName(),
+ getOrCreateFile(Loc), getLineNumber(Loc),
+ getDeclContextDescriptor(Ty->getDecl()));
}
static unsigned getDwarfCC(CallingConv CC) {
diff --git a/clang/test/CodeGenCXX/debug-info-nodebug.cpp b/clang/test/CodeGenCXX/debug-info-nodebug.cpp
index 9f140ef..1962b8c 100644
--- a/clang/test/CodeGenCXX/debug-info-nodebug.cpp
+++ b/clang/test/CodeGenCXX/debug-info-nodebug.cpp
@@ -1,5 +1,5 @@
-// RUN: %clang_cc1 -DSETNODEBUG=0 -emit-llvm -debug-info-kind=limited %s -o - | FileCheck %s --check-prefix=YESINFO
-// RUN: %clang_cc1 -DSETNODEBUG=1 -emit-llvm -debug-info-kind=limited %s -o - | FileCheck %s --check-prefix=NOINFO
+// RUN: %clang_cc1 -DSETNODEBUG=0 -emit-llvm -std=c++14 -debug-info-kind=limited %s -o - | FileCheck %s --check-prefix=YESINFO
+// RUN: %clang_cc1 -DSETNODEBUG=1 -emit-llvm -std=c++14 -debug-info-kind=limited %s -o - | FileCheck %s --check-prefix=NOINFO
#if SETNODEBUG
#define NODEBUG __attribute__((nodebug))
@@ -53,3 +53,15 @@
// NOINFO-NOT: !DIGlobalVariable(name: "static_local"
// YESINFO-DAG: !DILocalVariable(name: "normal_local"
// NOINFO-NOT: !DILocalVariable(name: "normal_local"
+
+template <typename T>
+using y NODEBUG = int;
+void func5() {
+ NODEBUG typedef int x;
+ x a;
+ y<int> b;
+}
+// YESINFO-DAG: !DIDerivedType(tag: DW_TAG_typedef, name: "x"
+// NOINFO-NOT: !DIDerivedType(tag: DW_TAG_typedef, name: "x"
+// YESINFO-DAG: !DIDerivedType(tag: DW_TAG_typedef, name: "y<int>"
+// NOINFO-NOT: !DIDerivedType(tag: DW_TAG_typedef, name: "y<int>"
diff --git a/clang/test/Misc/pragma-attribute-supported-attributes-list.test b/clang/test/Misc/pragma-attribute-supported-attributes-list.test
index 6e07e8e..aa71e0b 100644
--- a/clang/test/Misc/pragma-attribute-supported-attributes-list.test
+++ b/clang/test/Misc/pragma-attribute-supported-attributes-list.test
@@ -72,7 +72,7 @@
// CHECK-NEXT: NSConsumesSelf (SubjectMatchRule_objc_method)
// CHECK-NEXT: Naked (SubjectMatchRule_function)
// CHECK-NEXT: NoCommon (SubjectMatchRule_variable)
-// CHECK-NEXT: NoDebug (SubjectMatchRule_hasType_functionType, SubjectMatchRule_objc_method, SubjectMatchRule_variable_not_is_parameter)
+// CHECK-NEXT: NoDebug (SubjectMatchRule_type_alias, SubjectMatchRule_hasType_functionType, SubjectMatchRule_objc_method, SubjectMatchRule_variable_not_is_parameter)
// CHECK-NEXT: NoDestroy (SubjectMatchRule_variable)
// CHECK-NEXT: NoDuplicate (SubjectMatchRule_function)
// CHECK-NEXT: NoEscape (SubjectMatchRule_variable_is_parameter)
diff --git a/clang/test/Sema/attr-nodebug.c b/clang/test/Sema/attr-nodebug.c
index 3557784..3ae894a 100644
--- a/clang/test/Sema/attr-nodebug.c
+++ b/clang/test/Sema/attr-nodebug.c
@@ -2,7 +2,7 @@
int a __attribute__((nodebug));
-void b(int p __attribute__((nodebug))) { // expected-warning {{'nodebug' attribute only applies to functions, function pointers, Objective-C methods, and variables}}
+void b(int p __attribute__((nodebug))) { // expected-warning {{'nodebug' attribute only applies to typedefs, functions, function pointers, Objective-C methods, and variables}}
int b __attribute__((nodebug));
}