Add support for DW_AT_export_symbols for anonymous structs

Summary:
We add support for DW_AT_export_symbols to detect anonymous struct on top of the heuristics implemented in D66175
This should allow us to differentiate anonymous structs and unnamed structs.
We also fix TestTypeList.py which was incorrectly detecting an unnamed struct as an anonymous struct.

Differential Revision: https://reviews.llvm.org/D68961

2 files changed, 96 insertions, 0 deletions

diff --git a/lldb/test/Shell/SymbolFile/DWARF/anon_class_w_and_wo_export_symbols.ll b/lldb/test/Shell/SymbolFile/DWARF/anon_class_w_and_wo_export_symbols.ll
new file mode 100644
index 00000000000..b0a9f229505
--- /dev/null
+++ b/lldb/test/Shell/SymbolFile/DWARF/anon_class_w_and_wo_export_symbols.ll
@@ -0,0 +1,77 @@
+; This test verifies that we do the right thing with DIFlagExportSymbols which is the new
+; behavioir and without the DIFlagExportSymbols which is the old behavior for the given
+; definitions below.
+;
+;```
+; struct A{
+;   struct {
+;    int x;
+;   };
+;   struct {
+;    int y;
+;   };
+;   struct {
+;    int z;
+;   } unnamed;
+; } a;
+;```
+;
+; RUN: %clang++ -g -c -o %t.o %s
+; RUN: lldb-test symbols -dump-clang-ast %t.o | FileCheck %s
+; RUN: llvm-dwarfdump %t.o | FileCheck %s --check-prefix DWARFDUMP
+
+%struct.A = type { %struct.anon, %struct.anon.0, %struct.anon.1 }
+%struct.anon = type { i32 }
+%struct.anon.0 = type { i32 }
+%struct.anon.1 = type { i32 }
+
+@a = global %struct.A zeroinitializer, align 4, !dbg !0
+
+!llvm.module.flags = !{!21, !22}
+!llvm.dbg.cu = !{!2}
+!llvm.ident = !{!23}
+
+!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
+!1 = distinct !DIGlobalVariable(name: "a", scope: !2, file: !3, line: 11, type: !6, isLocal: false, isDefinition: true)
+!2 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !3, producer: "clang version 10.0.0", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5, nameTableKind: None)
+!3 = !DIFile(filename: "anon_old_new.cpp", directory: "/dir")
+!4 = !{}
+!5 = !{!0}
+!6 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "A", file: !3, line: 1, size: 96, flags: DIFlagTypePassByValue, elements: !7, identifier: "_ZTS1A")
+; CHECK: struct A definition
+!7 = !{!8, !13, !17}
+!8 = !DIDerivedType(tag: DW_TAG_member, scope: !6, file: !3, line: 2, baseType: !9, size: 32)
+!9 = distinct !DICompositeType(tag: DW_TAG_structure_type, scope: !6, file: !3, line: 2, size: 32, flags: DIFlagExportSymbols | DIFlagTypePassByValue, elements: !10, identifier: "_ZTSN1AUt_E")
+; Correctly identify an anonymous class with DIFlagExportSymbols
+; CHECK: struct definition
+; CHECK: DefinitionData is_anonymous pass_in_registers aggregate standard_layout trivially_copyable pod trivial literal
+!10 = !{!11}
+!11 = !DIDerivedType(tag: DW_TAG_member, name: "x", scope: !9, file: !3, line: 3, baseType: !12, size: 32)
+!12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!13 = !DIDerivedType(tag: DW_TAG_member, scope: !6, file: !3, line: 5, baseType: !14, size: 32, offset: 32)
+!14 = distinct !DICompositeType(tag: DW_TAG_structure_type, scope: !6, file: !3, line: 5, size: 32, flags: DIFlagTypePassByValue, elements: !15, identifier: "_ZTSN1AUt0_E")
+; Correctly identify an anonymous class without DIFlagExportSymbols
+; This works b/c we have additional checks when we fields to A.
+; CHECK: struct definition
+; CHECK: DefinitionData is_anonymous pass_in_registers aggregate standard_layout trivially_copyable pod trivial literal
+!15 = !{!16}
+!16 = !DIDerivedType(tag: DW_TAG_member, name: "y", scope: !14, file: !3, line: 6, baseType: !12, size: 32)
+!17 = !DIDerivedType(tag: DW_TAG_member, name: "unnamed", scope: !6, file: !3, line: 10, baseType: !18, size: 32, offset: 64)
+!18 = distinct !DICompositeType(tag: DW_TAG_structure_type, scope: !6, file: !3, line: 8, size: 32, flags: DIFlagTypePassByValue, elements: !19, identifier: "_ZTSN1AUt1_E")
+; Correctly identify an unamed class
+; CHECK: struct definition
+; CHECK: DefinitionData pass_in_registers aggregate standard_layout trivially_copyable pod trivial literal
+!19 = !{!20}
+!20 = !DIDerivedType(tag: DW_TAG_member, name: "z", scope: !18, file: !3, line: 9, baseType: !12, size: 32)
+!21 = !{i32 2, !"Dwarf Version", i32 4}
+!22 = !{i32 2, !"Debug Info Version", i32 3}
+!23 = !{!"clang version 10.0.0"}
+
+; DWARFDUMP: DW_TAG_structure_type
+; DWARFDUMP: DW_AT_name	("A")
+;
+; DWARFDUMP: DW_TAG_structure_type
+; DWARFDUMP: DW_AT_export_symbols	(true)
+;
+; DWARFDUMP: DW_TAG_structure_type
+; DWARFDUMP-NOT: DW_AT_export_symbols   (true)
diff --git a/lldb/test/Shell/SymbolFile/DWARF/clang-ast-from-dwarf-unamed-and-anon-structs.cpp b/lldb/test/Shell/SymbolFile/DWARF/clang-ast-from-dwarf-unamed-and-anon-structs.cpp
new file mode 100644
index 00000000000..f1254fe3b1b
--- /dev/null
+++ b/lldb/test/Shell/SymbolFile/DWARF/clang-ast-from-dwarf-unamed-and-anon-structs.cpp
@@ -0,0 +1,19 @@
+// Test to verify we are corectly generating anonymous flags when parsing
+// anonymous class and unnamed structs from DWARF to the a clang AST node.
+
+// RUN: %clang++ -g -c -o %t.o %s
+// RUN: lldb-test symbols -dump-clang-ast %t.o | FileCheck %s
+
+struct A {
+  struct {
+    int x;
+  };
+  struct {
+    int y;
+  } C;
+} a;
+
+// CHECK: A::(anonymous struct)
+// CHECK: |-DefinitionData is_anonymous pass_in_registers aggregate standard_layout trivially_copyable pod trivial literal
+// CHECK: A::(anonymous struct)
+// CHECK: |-DefinitionData pass_in_registers aggregate standard_layout trivially_copyable pod trivial literal