diff --git a/llvm/include/llvm/BinaryFormat/Wasm.h b/llvm/include/llvm/BinaryFormat/Wasm.h --- a/llvm/include/llvm/BinaryFormat/Wasm.h +++ b/llvm/include/llvm/BinaryFormat/Wasm.h @@ -330,6 +330,8 @@ enum : unsigned { WASM_COMDAT_DATA = 0x0, WASM_COMDAT_FUNCTION = 0x1, + // GLOBAL, EVENT, and TABLE are in here but LLVM doesn't use them yet. + WASM_COMDAT_SECTION = 0x5, }; // Kind codes used in the custom "linking" section in the WASM_SYMBOL_TABLE diff --git a/llvm/include/llvm/Object/Wasm.h b/llvm/include/llvm/Object/Wasm.h --- a/llvm/include/llvm/Object/Wasm.h +++ b/llvm/include/llvm/Object/Wasm.h @@ -108,6 +108,7 @@ uint32_t Type = 0; // Section type (See below) uint32_t Offset = 0; // Offset with in the file StringRef Name; // Section name (User-defined sections only) + uint32_t Comdat = UINT32_MAX; // From the "comdat info" section ArrayRef Content; // Section content std::vector Relocations; // Relocations for this section }; diff --git a/llvm/lib/MC/MCContext.cpp b/llvm/lib/MC/MCContext.cpp --- a/llvm/lib/MC/MCContext.cpp +++ b/llvm/lib/MC/MCContext.cpp @@ -644,7 +644,7 @@ StringRef CachedName = Entry.first.SectionName; - MCSymbol *Begin = createSymbol(CachedName, false, false); + MCSymbol *Begin = createSymbol(CachedName, true, false); cast(Begin)->setType(wasm::WASM_SYMBOL_TYPE_SECTION); MCSectionWasm *Result = new (WasmAllocator.Allocate()) diff --git a/llvm/lib/MC/MCObjectFileInfo.cpp b/llvm/lib/MC/MCObjectFileInfo.cpp --- a/llvm/lib/MC/MCObjectFileInfo.cpp +++ b/llvm/lib/MC/MCObjectFileInfo.cpp @@ -974,9 +974,6 @@ return Ctx->getELFSection(Name, ELF::SHT_PROGBITS, ELF::SHF_GROUP, 0, utostr(Hash)); case Triple::Wasm: - // FIXME: When using dwarf 5, the .debug_info section is used for type units - // but that section already exists, so attempting to get it as a comdate - // section triggers an assert. return Ctx->getWasmSection(Name, SectionKind::getMetadata(), utostr(Hash), MCContext::GenericSectionID); case Triple::MachO: diff --git a/llvm/lib/MC/WasmObjectWriter.cpp b/llvm/lib/MC/WasmObjectWriter.cpp --- a/llvm/lib/MC/WasmObjectWriter.cpp +++ b/llvm/lib/MC/WasmObjectWriter.cpp @@ -1421,6 +1421,16 @@ continue; } + // Custom sections can also belong to COMDAT groups. In this case the + // decriptor's "index" field is the section index (in the final object + // file), but that is not known until after layout, so it must be fixed up + // later + if (const MCSymbolWasm *C = Section.getGroup()) { + Comdats[C->getName()].emplace_back( + WasmComdatEntry{wasm::WASM_COMDAT_SECTION, + static_cast(CustomSections.size())}); + } + CustomSections.emplace_back(Name, &Section); } } @@ -1799,9 +1809,17 @@ DataSectionIndex = writeDataSection(Layout); } - for (auto &CustomSection : CustomSections) { - writeCustomSection(CustomSection, Asm, Layout); + // The Sections in the COMDAT list have placeholder indices (their index among + // custom sections, rather than among all sections). Fix them up here. + for (auto &Group : Comdats) { + for (auto &Entry : Group.second) { + if (Entry.Kind == wasm::WASM_COMDAT_SECTION) { + Entry.Index += SectionCount; + } + } } + for (auto &CustomSection : CustomSections) + writeCustomSection(CustomSection, Asm, Layout); if (Mode != DwoMode::DwoOnly) { writeLinkingMetaDataSection(SymbolInfos, InitFuncs, Comdats); diff --git a/llvm/lib/Object/WasmObjectFile.cpp b/llvm/lib/Object/WasmObjectFile.cpp --- a/llvm/lib/Object/WasmObjectFile.cpp +++ b/llvm/lib/Object/WasmObjectFile.cpp @@ -745,6 +745,15 @@ object_error::parse_failed); getDefinedFunction(Index).Comdat = ComdatIndex; break; + case wasm::WASM_COMDAT_SECTION: + if (Index >= Sections.size()) + return make_error( + "COMDAT section index out of range", object_error::parse_failed); + if (Sections[Index].Type != wasm::WASM_SEC_CUSTOM) + return make_error( + "Non-custom section in a COMDAT", object_error::parse_failed); + Sections[Index].Comdat = ComdatIndex; + break; } } } diff --git a/llvm/lib/ObjectYAML/WasmYAML.cpp b/llvm/lib/ObjectYAML/WasmYAML.cpp --- a/llvm/lib/ObjectYAML/WasmYAML.cpp +++ b/llvm/lib/ObjectYAML/WasmYAML.cpp @@ -472,6 +472,7 @@ #define ECase(X) IO.enumCase(Kind, #X, wasm::WASM_COMDAT_##X); ECase(FUNCTION); ECase(DATA); + ECase(SECTION); #undef ECase } diff --git a/llvm/test/DebugInfo/WebAssembly/dwarf-headers.ll b/llvm/test/DebugInfo/WebAssembly/dwarf-headers.ll --- a/llvm/test/DebugInfo/WebAssembly/dwarf-headers.ll +++ b/llvm/test/DebugInfo/WebAssembly/dwarf-headers.ll @@ -8,17 +8,15 @@ ; RUN: | llvm-dwarfdump -v - | FileCheck %s --check-prefix=O-4 ; RUN: llvm-dwarfdump -v %t.dwo | FileCheck %s --check-prefix=DWO-4 -; TODO: enable testing for dwarf v5 with type units -; (See the FIXME in MCObjectFileInfo::getDwarfComdatSection) -; RU N: llc -dwarf-version=5 -generate-type-units \ -; RU N: -filetype=obj -O0 -mtriple= < %s \ -; RU N: | llvm-dwarfdump -v - | FileCheck %s --check-prefix=SINGLE-5 - -; RU N: llc -split-dwarf-file=foo.dwo -split-dwarf-output=%t.dwo \ -; RU N: -dwarf-version=5 -generate-type-units \ -; RU N: -filetype=obj -O0 -mtriple= < %s \ -; RU N: | llvm-dwarfdump -v - | FileCheck %s --check-prefix=O-5 -; RU N: llvm-dwarfdump -v %t.dwo | FileCheck %s --check-prefix=DWO-5 +; RUN: llc -dwarf-version=5 -generate-type-units \ +; RUN: -filetype=obj -O0 -mtriple= < %s \ +; RUN: | llvm-dwarfdump -v - | FileCheck %s --check-prefix=SINGLE-5 + +; RUN: llc -split-dwarf-file=foo.dwo -split-dwarf-output=%t.dwo \ +; RUN: -dwarf-version=5 -generate-type-units \ +; RUN: -filetype=obj -O0 -mtriple= < %s \ +; RUN: | llvm-dwarfdump -v - | FileCheck %s --check-prefix=O-5 +; RUN: llvm-dwarfdump -v %t.dwo | FileCheck %s --check-prefix=DWO-5 ; This test is derived from test/CodeGen/X86/dwarf-headers.ll diff --git a/llvm/test/MC/WebAssembly/comdat-sections.ll b/llvm/test/MC/WebAssembly/comdat-sections.ll new file mode 100644 --- /dev/null +++ b/llvm/test/MC/WebAssembly/comdat-sections.ll @@ -0,0 +1,37 @@ +; RUN: llc -dwarf-version=4 -generate-type-units \ +; RUN: -filetype=obj -O0 -mtriple=wasm32-unknown-unknown < %s \ +; RUN: | obj2yaml | FileCheck %s + + +; CHECK: Comdats: +; CHECK: - Name: '4721183873463917179' +; CHECK: Entries: +; CHECK: - Kind: SECTION +; CHECK: Index: 3 + +; ModuleID = 't.cpp' +source_filename = "t.cpp" +target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128" +target triple = "wasm32-unknown-unknown-wasm" + +%struct.S = type { i32 } + +@s = global %struct.S zeroinitializer, align 4, !dbg !0 + +!llvm.dbg.cu = !{!2} +!llvm.module.flags = !{!10, !11} +!llvm.ident = !{!12} + +!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) +!1 = distinct !DIGlobalVariable(name: "s", scope: !2, file: !3, line: 5, type: !6, isLocal: false, isDefinition: true) +!2 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !3, producer: "clang version 5.0.0 (trunk 295942)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5) +!3 = !DIFile(filename: "t.cpp", directory: "/home/probinson/projects/scratch") +!4 = !{} +!5 = !{!0} +!6 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "S", file: !3, line: 1, size: 32, elements: !7, identifier: "_ZTS1S") +!7 = !{!8} +!8 = !DIDerivedType(tag: DW_TAG_member, name: "s1", scope: !6, file: !3, line: 2, baseType: !9, size: 32) +!9 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!10 = !{i32 2, !"Dwarf Version", i32 4} +!11 = !{i32 2, !"Debug Info Version", i32 3} +!12 = !{!"clang version 5.0.0 (trunk 295942)"} diff --git a/llvm/tools/obj2yaml/wasm2yaml.cpp b/llvm/tools/obj2yaml/wasm2yaml.cpp --- a/llvm/tools/obj2yaml/wasm2yaml.cpp +++ b/llvm/tools/obj2yaml/wasm2yaml.cpp @@ -107,6 +107,14 @@ } SegmentIndex++; } + uint32_t SectionIndex = 0; + for (const auto &Sec : Obj.sections()) { + const WasmSection &WasmSec = Obj.getWasmSection(Sec); + if (WasmSec.Comdat != UINT32_MAX) + LinkingSec->Comdats[WasmSec.Comdat].Entries.emplace_back( + WasmYAML::ComdatEntry{wasm::WASM_COMDAT_SECTION, SectionIndex}); + SectionIndex++; + } uint32_t SymbolIndex = 0; for (const wasm::WasmSymbolInfo &Symbol : Obj.linkingData().SymbolTable) {