From b278eba445ac227c82f9000a7709d7172e716ad5 Mon Sep 17 00:00:00 2001 From: Esme-Yi Date: Mon, 26 Jul 2021 03:47:02 +0000 Subject: [PATCH] [Debug-Info][llvm-dwarfdump] Don't use DW_FORM_data4/8 to encode the constants for DW_AT_data_member_location. Summary: In DWARF v3, DW_FORM_data4/8 in DW_AT_data_member_location are interpreted as location list pointers. Interpreting constants as pointers is not expected, so we use DW_FORM_udata to encode the constants. Reviewed By: probinson Differential Revision: https://reviews.llvm.org/D105687 --- lib/CodeGen/AsmPrinter/DwarfUnit.cpp | 15 ++++++-- test/DebugInfo/MSP430/dwarf-basics.ll | 2 +- .../PowerPC/data_member_location_dwarf3.ll | 36 +++++++++++++++++++ 3 files changed, 49 insertions(+), 4 deletions(-) create mode 100644 test/DebugInfo/PowerPC/data_member_location_dwarf3.ll diff --git a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp index 5c6dd43b816..344d30fad34 100644 --- a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp @@ -1618,9 +1618,18 @@ DIE &DwarfUnit::constructMemberDIE(DIE &Buffer, const DIDerivedType *DT) { addUInt(*MemLocationDie, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst); addUInt(*MemLocationDie, dwarf::DW_FORM_udata, OffsetInBytes); addBlock(MemberDie, dwarf::DW_AT_data_member_location, MemLocationDie); - } else if (!IsBitfield || DD->useDWARF2Bitfields()) - addUInt(MemberDie, dwarf::DW_AT_data_member_location, None, - OffsetInBytes); + } else if (!IsBitfield || DD->useDWARF2Bitfields()) { + // In DWARF v3, DW_FORM_data4/8 in DW_AT_data_member_location are + // interpreted as location-list pointers. Interpreting constants as + // pointers is not expected, so we use DW_FORM_udata to encode the + // constants here. + if (DD->getDwarfVersion() == 3) + addUInt(MemberDie, dwarf::DW_AT_data_member_location, + dwarf::DW_FORM_udata, OffsetInBytes); + else + addUInt(MemberDie, dwarf::DW_AT_data_member_location, None, + OffsetInBytes); + } } if (DT->isProtected()) diff --git a/test/DebugInfo/MSP430/dwarf-basics.ll b/test/DebugInfo/MSP430/dwarf-basics.ll index c446247eacf..d3244720f81 100644 --- a/test/DebugInfo/MSP430/dwarf-basics.ll +++ b/test/DebugInfo/MSP430/dwarf-basics.ll @@ -84,7 +84,7 @@ ; CHECK: DW_AT_type (0x{{.*}} "*") ; CHECK: DW_AT_decl_file ("/tmp{{[/\\]}}dwarf-basics.c") ; CHECK: DW_AT_decl_line (2) -; CHECK: DW_AT_data_member_location (0x00) +; CHECK: DW_AT_data_member_location (0) ; CHECK: NULL diff --git a/test/DebugInfo/PowerPC/data_member_location_dwarf3.ll b/test/DebugInfo/PowerPC/data_member_location_dwarf3.ll new file mode 100644 index 00000000000..090f6d5577f --- /dev/null +++ b/test/DebugInfo/PowerPC/data_member_location_dwarf3.ll @@ -0,0 +1,36 @@ +; RUN: llc -mtriple=powerpc64le-unknown-linux-gnu -dwarf-version=3 -O0 -o - -filetype=obj < %s | \ +; RUN: llvm-dwarfdump -v -debug-info -name g -| FileCheck %s + +; CHECK: DW_AT_name [DW_FORM_strp] {{.*}} "g" +; CHECK: DW_AT_data_member_location [DW_FORM_udata] (65536) + +; ModuleID = '1.cpp' +source_filename = "1.cpp" + +%struct.e = type { [65536 x i8], i8 } + +@E = dso_local local_unnamed_addr global %struct.e zeroinitializer, align 1, !dbg !0 + +!llvm.dbg.cu = !{!2} +!llvm.module.flags = !{!14, !15, !16, !17} +!llvm.ident = !{!18} + +!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) +!1 = distinct !DIGlobalVariable(name: "E", scope: !2, file: !3, line: 5, type: !6, isLocal: false, isDefinition: true) +!2 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !3, producer: "clang version 13.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5, splitDebugInlining: false, nameTableKind: None) +!3 = !DIFile(filename: "1.cpp", directory: "/tmp") +!4 = !{} +!5 = !{!0} +!6 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "e", file: !3, line: 1, size: 524296, flags: DIFlagTypePassByValue, elements: !7, identifier: "_ZTS1e") +!7 = !{!8, !13} +!8 = !DIDerivedType(tag: DW_TAG_member, name: "f", scope: !6, file: !3, line: 2, baseType: !9, size: 524288) +!9 = !DICompositeType(tag: DW_TAG_array_type, baseType: !10, size: 524288, elements: !11) +!10 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_unsigned_char) +!11 = !{!12} +!12 = !DISubrange(count: 65536) +!13 = !DIDerivedType(tag: DW_TAG_member, name: "g", scope: !6, file: !3, line: 3, baseType: !10, size: 8, offset: 524288) +!14 = !{i32 7, !"Dwarf Version", i32 3} +!15 = !{i32 2, !"Debug Info Version", i32 3} +!16 = !{i32 1, !"wchar_size", i32 4} +!17 = !{i32 7, !"uwtable", i32 1} +!18 = !{!"clang version 13.0.0"}