[DebugInfo][CallSites] Remove decl subprograms from 'retainedTypes:'

After the D70350, the retainedTypes: isn't being used for the purpose
of call site debug info for extern calls, so it is safe to delete it
from IR representation.
We are also adding a test to ensure the subprogram isn't stored within
the retainedTypes: from corresponding DICompileUnit.

Differential Revision: https://reviews.llvm.org/D80369

Author: Djordje Todorovic

clang/lib/CodeGen/CGDebugInfo.cpp

@@ -3900,7 +3900,7 @@ void CGDebugInfo::EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
   if (IsDeclForCallSite)
     Fn->setSubprogram(SP);
 
-  DBuilder.retainType(SP);
+  DBuilder.finalizeSubprogram(SP);
 }
 
 void CGDebugInfo::EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,

clang/test/CodeGen/debug-info-extern-call.c

@@ -1,6 +1,10 @@
 // When entry values are emitted, expect a subprogram for extern decls so that
 // the dwarf generator can describe call site parameters at extern call sites.
 //
+// Initial implementation relied on the 'retainedTypes:' from the corresponding
+// DICompileUnit, so we also ensure that we do not store the extern declaration
+// subprogram into the 'retainedTypes:'.
+//
 // RUN: %clang -g -O2 -target x86_64-none-linux-gnu -S -emit-llvm %s -o - \
 // RUN:   | FileCheck %s -check-prefix=DECLS-FOR-EXTERN
 
@@ -17,6 +21,8 @@
 // RUN: %clang -g -O2 -target x86_64-none-linux-gnu -gsce -S -emit-llvm %s -o - \
 // RUN:   | FileCheck %s -check-prefix=NO-DECLS-FOR-EXTERN
 
+// DECLS-FOR-EXTERN-NOT: !DICompileUnit({{.*}}retainedTypes: ![[RETTYPES:[0-9]+]]
+// DECLS-FOR-EXTERN-NOT: ![[RETTYPES]] = !{
 // DECLS-FOR-EXTERN: !DISubprogram(name: "fn1"
 // DECLS-FOR-EXTERN-NOT: !DISubprogram(name: "memcmp"
 // DECLS-FOR-EXTERN-NOT: !DISubprogram(name: "__some_reserved_name"

clang/test/Modules/DebugInfoTransitiveImport.m

@@ -12,10 +12,10 @@
 
 // Definition of left:
 // CHECK: !DICompileUnit({{.*}}dwoId:
-// CHECK: ![[LEFT:[0-9]+]] = !DIFile({{.*}}diamond_left.h
 // CHECK: !DIImportedEntity(tag: DW_TAG_imported_declaration,
-// CHECK-SAME:              entity: ![[MODULE:.*]], file: ![[LEFT]], line: 3)
+// CHECK-SAME:              entity: ![[MODULE:.*]], file: ![[LEFT:.*]], line: 3)
 // CHECK: ![[MODULE]] = !DIModule(scope: null, name: "diamond_top"
+// CHECK: ![[LEFT]] = !DIFile({{.*}}diamond_left.h
 
 // Skeleton for top:
 // CHECK: !DICompileUnit({{.*}}splitDebugFilename: {{.*}}diamond_top{{.*}}dwoId:

clang/test/Modules/ModuleDebugInfo.cpp

@@ -51,15 +51,6 @@
 // CHECK-SAME:             )
 // CHECK: !DIEnumerator(name: "e5", value: 5, isUnsigned: true)
 
-// CHECK: !DIDerivedType(tag: DW_TAG_typedef, name: "B",
-// no mangled name here yet.
-
-// This type is anchored by a function parameter.
-// CHECK: !DICompositeType(tag: DW_TAG_class_type, name: "A<void>"
-// CHECK-SAME:             elements:
-// CHECK-SAME:             templateParams:
-// CHECK-SAME:             identifier: "_ZTSN8DebugCXX1AIJvEEE")
-
 // CHECK: !DICompositeType(tag: DW_TAG_structure_type, name: "Struct"
 // CHECK-SAME:             identifier: "_ZTSN8DebugCXX6StructE")
 
@@ -85,6 +76,12 @@
 // CHECK-SAME:             templateParams:
 // CHECK-SAME:             identifier: "_ZTSN8DebugCXX8TemplateIlNS_6traitsIlEEEE")
 
+// This type is anchored by a function parameter.
+// CHECK: !DICompositeType(tag: DW_TAG_class_type, name: "A<void>"
+// CHECK-SAME:             elements:
+// CHECK-SAME:             templateParams:
+// CHECK-SAME:             identifier: "_ZTSN8DebugCXX1AIJvEEE")
+
 // CHECK: !DIDerivedType(tag: DW_TAG_typedef, name: "FloatInstantiation"
 // no mangled name here yet.
 
@@ -93,6 +90,9 @@
 // CHECK-SAME:             flags: DIFlagFwdDecl
 // CHECK-SAME:             identifier: "_ZTSN8DebugCXX8TemplateIfNS_6traitsIfEEEE")
 
+// CHECK: !DIDerivedType(tag: DW_TAG_typedef, name: "B",
+// no mangled name here yet.
+
 // CHECK: !DICompositeType(tag: DW_TAG_structure_type, name: "Virtual"
 // CHECK-SAME:             elements:
 // CHECK-SAME:             identifier: "_ZTS7Virtual")

clang/test/Modules/ModuleDebugInfo.m

@@ -36,19 +36,13 @@
 // CHECK-NOT:              name:
 // CHECK-SAME:             elements:
 
-// CHECK: !DISubprogram(name: "+[ObjCClass classMethod]",
-// CHECK-SAME:          scope: ![[MODULE]],
+// CHECK: !DICompositeType(tag: DW_TAG_structure_type, name: "FwdDecl",
+// CHECK-SAME:             scope: ![[MODULE]],
 
 // CHECK: !DICompositeType(tag: DW_TAG_structure_type, name: "ObjCClass",
 // CHECK-SAME:             scope: ![[MODULE]],
 // CHECK-SAME:             elements
 
-// The forward declaration should not be in the module scope.
-// CHECK: !DICompositeType(tag: DW_TAG_structure_type, name: "OpaqueData", file
-
-// CHECK: !DICompositeType(tag: DW_TAG_structure_type, name: "FwdDecl",
-// CHECK-SAME:             scope: ![[MODULE]],
-
 // CHECK: !DICompositeType(tag: DW_TAG_structure_type, name: "ObjCClassWithPrivateIVars",
 // CHECK-SAME:             scope: ![[MODULE]],
 // CHECK-SAME:             elements
@@ -85,11 +79,8 @@
 // The output order is sublty different for module vs. pch,
 // so these are checked separately:
 //
-// CHECK2: !DISubprogram(name: "+[ObjCClass classMethod]"
-// CHECK2: !DISubprogram(name: "-[ObjCClass instanceMethodWithInt:]"
+// CHECK2: !DICompositeType(tag: DW_TAG_structure_type, name: "FwdDecl",
 // CHECK2: !DICompositeType(tag: DW_TAG_structure_type, name: "ObjCClass",
 // CHECK2: !DIObjCProperty(name: "property",
 // CHECK2: !DIDerivedType(tag: DW_TAG_member, name: "ivar"
-// CHECK2: !DISubprogram(name: "-[Category(Category) categoryMethod]"
-// CHECK2: !DICompositeType(tag: DW_TAG_structure_type, name: "FwdDecl",
 // CHECK2: !DIDerivedType(tag: DW_TAG_typedef, name: "InnerEnum"