paolosev created this revision. paolosev added reviewers: jasonmolenda, clayborg. paolosev added projects: LLDB, LLVM. Herald added subscribers: llvm-commits, lldb-commits, sunfish, aheejin, jgravelle-google, sbc100, aprantl, mgorny, dschuff.
Current versions of Clang emit (partial) DWARF debug information in WebAssembly modules and we can leverage this debug information to give LLDB the ability to do source-level debugging of Wasm code that runs in a WebAssembly engine. A way to do this could be to use the remote debugging functionalities provided by LLDB via the GDB-remote protocol. Remote debugging can indeed be useful not only to connect a debugger to a process running on a remote machine, but also to connect the debugger to a managed VM or script engine that runs locally, provided that the engine implements a GDB-remote stub that offers the ability to access the engine runtime internal state. To make this work, the GDB-remote protocol would need to be extended with a few Wasm-specific custom query commands, used to access aspects of the Wasm engine state (like the Wasm memory, Wasm local and global variables, and so on). Furthermore, the DWARF format would need to be enriched with a few Wasm-specific extensions, here detailed: https://yurydelendik.github.io/webassembly-dwarf. This CL only introduces classes ObjectFileWasm, SymbolVendorWasm and DynamicLoaderWasmDYLD as a first step to enable LLDB debugging of WebAssembly targets. In more detail: - Class **ObjectFileWasm** represents a WebAssembly module loaded in the debuggee process. It knows how to parse Wasm module and store the Code section and the DWARF-specific sections. - Class **SymbolVendorWasm** takes care of DWARF data for a ObjectFileWasm, which can be either embedded in the modules, or stripped into a separate Wasm module which only contains DWARF sections. - In WebAssembly, linear memory is disjointed from code space. The VM can load multiple instances of a module, which logically share the same code. Class **DynamicLoaderWasmDYLD** manages the mapping of Wasm code address in the debuggee address space. Repository: rG LLVM Github Monorepo https://reviews.llvm.org/D71575 Files: lldb/include/lldb/Utility/ArchSpec.h lldb/source/API/SystemInitializerFull.cpp lldb/source/Plugins/DynamicLoader/CMakeLists.txt lldb/source/Plugins/DynamicLoader/WASM-DYLD/CMakeLists.txt lldb/source/Plugins/DynamicLoader/WASM-DYLD/DynamicLoaderWasmDYLD.cpp lldb/source/Plugins/DynamicLoader/WASM-DYLD/DynamicLoaderWasmDYLD.h lldb/source/Plugins/ObjectFile/CMakeLists.txt lldb/source/Plugins/ObjectFile/WASM/CMakeLists.txt lldb/source/Plugins/ObjectFile/WASM/ObjectFileWasm.cpp lldb/source/Plugins/ObjectFile/WASM/ObjectFileWasm.h lldb/source/Plugins/SymbolVendor/CMakeLists.txt lldb/source/Plugins/SymbolVendor/WASM/CMakeLists.txt lldb/source/Plugins/SymbolVendor/WASM/SymbolVendorWasm.cpp lldb/source/Plugins/SymbolVendor/WASM/SymbolVendorWasm.h lldb/source/Utility/ArchSpec.cpp lldb/unittests/ObjectFile/CMakeLists.txt lldb/unittests/ObjectFile/WASM/CMakeLists.txt lldb/unittests/ObjectFile/WASM/TestObjectFileWasm.cpp llvm/include/llvm/BinaryFormat/ELF.h
Index: llvm/include/llvm/BinaryFormat/ELF.h =================================================================== --- llvm/include/llvm/BinaryFormat/ELF.h +++ llvm/include/llvm/BinaryFormat/ELF.h @@ -311,6 +311,7 @@ EM_RISCV = 243, // RISC-V EM_LANAI = 244, // Lanai 32-bit processor EM_BPF = 247, // Linux kernel bpf virtual machine + EM_WASM = 248, // WebAssembly }; // Object file classes. Index: lldb/unittests/ObjectFile/WASM/TestObjectFileWasm.cpp =================================================================== --- /dev/null +++ lldb/unittests/ObjectFile/WASM/TestObjectFileWasm.cpp @@ -0,0 +1,282 @@ +//===-- TestObjectFileWasm.cpp -----------------------------------*- C++ +//-*-===// +// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "gtest/gtest.h" + +#include "Plugins/ObjectFile/WASM/ObjectFileWasm.h" +#include "Plugins/Platform/gdb-server/PlatformRemoteGDBServer.h" +#include "TestingSupport/TestUtilities.h" + +#include "lldb/Core/Debugger.h" +#include "lldb/Core/Module.h" +#include "lldb/Core/ModuleSpec.h" +#include "lldb/Core/Section.h" +#include "lldb/Host/FileSystem.h" +#include "lldb/Host/HostInfo.h" +#include "lldb/Target/Platform.h" +#include "lldb/Target/Target.h" +#include "lldb/Utility/ArchSpec.h" +#include "lldb/Utility/Reproducer.h" +#include "llvm/Testing/Support/Error.h" + +using namespace lldb_private; +using namespace lldb_private::repro; +using namespace lldb; + +class ObjectFileWasmTest : public testing::Test { +public: + void SetUp() override { + llvm::cantFail(Reproducer::Initialize(ReproducerMode::Off, llvm::None)); + FileSystem::Initialize(); + HostInfo::Initialize(); + wasm::ObjectFileWasm::Initialize(); + } + + void TearDown() override { + wasm::ObjectFileWasm::Terminate(); + HostInfo::Terminate(); + FileSystem::Terminate(); + Reproducer::Terminate(); + } +}; + +TEST_F(ObjectFileWasmTest, SectionsResolveConsistently) { + auto ExpectedFile = TestFile::fromYaml(R"( +--- !WASM +FileHeader: + Version: 0x00000001 +Sections: + - Type: TYPE + Signatures: + - Index: 0 + ParamTypes: + - I32 + ReturnTypes: + - I32 + - Type: FUNCTION + FunctionTypes: [ 0 ] + - Type: TABLE + Tables: + - ElemType: FUNCREF + Limits: + Flags: [ HAS_MAX ] + Initial: 0x00000001 + Maximum: 0x00000001 + - Type: MEMORY + Memories: + - Initial: 0x00000002 + - Type: GLOBAL + Globals: + - Index: 0 + Type: I32 + Mutable: true + InitExpr: + Opcode: I32_CONST + Value: 66560 + - Type: EXPORT + Exports: + - Name: memory + Kind: MEMORY + Index: 0 + - Name: square + Kind: FUNCTION + Index: 0 + - Type: CODE + Functions: + - Index: 0 + Locals: + - Type: I32 + Count: 6 + Body: 238080808000210141102102200120026B21032003200036020C200328020C2104200328020C2105200420056C210620060F0B + - Type: CUSTOM + Name: name + FunctionNames: + - Index: 0 + Name: square + - Type: CUSTOM + Name: producers + Languages: + - Name: C99 + Version: '' + Tools: + - Name: clang + Version: '10.0.0' + - Type: CUSTOM + Name: external_debug_info + Payload: 0F7371756172655F73796D2E7761736D +... +)"); + + ASSERT_THAT_EXPECTED(ExpectedFile, llvm::Succeeded()); + + ArchSpec arch("wasm32-unknown-unknown-wasm"); + Platform::SetHostPlatform( + platform_gdb_server::PlatformRemoteGDBServer::CreateInstance(true, + &arch)); + + DebuggerSP debugger_sp = Debugger::CreateInstance(); + ASSERT_TRUE(debugger_sp); + + TargetSP target_sp; + PlatformSP platform_sp; + Status error = debugger_sp->GetTargetList().CreateTarget( + *debugger_sp, "", arch, eLoadDependentsNo, platform_sp, target_sp); + ASSERT_TRUE(target_sp); + ASSERT_TRUE(target_sp->GetArchitecture().IsValid()); + ASSERT_TRUE(platform_sp); + + ModuleSpec spec{FileSpec(ExpectedFile->name())}; + auto module_sp = std::make_shared<Module>(spec); + + ObjectFile *object_file = module_sp->GetObjectFile(); + ASSERT_NE(object_file, nullptr); + object_file->SetLoadAddress(*target_sp, 4ULL << 32, false); + + UUID uuid = object_file->GetUUID(); + ASSERT_FALSE(uuid.IsValid()); + + ArchSpec arch_spec = object_file->GetArchitecture(); + ASSERT_EQ(llvm::Triple::wasm32, arch_spec.GetTriple().getArch()); + + uint32_t address_size = object_file->GetAddressByteSize(); + ASSERT_EQ(4, address_size); + + SectionList *list = module_sp->GetSectionList(); + ASSERT_NE(nullptr, list); + + auto code_sp = list->FindSectionByName(ConstString("code")); + ASSERT_NE(nullptr, code_sp); + ASSERT_EQ(0, code_sp->GetFileAddress()); +} + +TEST_F(ObjectFileWasmTest, DwarfSectionsResolveConsistently) { + auto ExpectedFile = TestFile::fromYaml(R"( +--- !WASM +FileHeader: + Version: 0x00000001 +Sections: + - Type: TYPE + Signatures: + - Index: 0 + ParamTypes: + - I32 + ReturnTypes: + - I32 + - Type: FUNCTION + FunctionTypes: [ 0 ] + - Type: TABLE + Tables: + - ElemType: FUNCREF + Limits: + Flags: [ HAS_MAX ] + Initial: 0x00000001 + Maximum: 0x00000001 + - Type: MEMORY + Memories: + - Initial: 0x00000002 + - Type: GLOBAL + Globals: + - Index: 0 + Type: I32 + Mutable: true + InitExpr: + Opcode: I32_CONST + Value: 66560 + - Type: EXPORT + Exports: + - Name: memory + Kind: MEMORY + Index: 0 + - Name: square + Kind: FUNCTION + Index: 0 + - Type: CODE + Functions: + - Index: 0 + Locals: + - Type: I32 + Count: 6 + Body: 238080808000210141102102200120026B21032003200036020C200328020C2104200328020C2105200420056C210620060F0B + - Type: CUSTOM + Name: .debug_info + Payload: 4C0000000400000000000401000000000C005D00000000000000750000000200000036000000020200000036000000960000000101480000000302230CA100000001014800000000049D000000050400 + - Type: CUSTOM + Name: .debug_abbrev + Payload: 011101250E1305030E10171B0E110112060000022E0111011206030E3A0B3B0B271949133F1900000305000218030E3A0B3B0B49130000042400030E3E0B0B0B000000 + - Type: CUSTOM + Name: .debug_line + Payload: 5100000004002F000000010101FB0E0D000101010100000001000001673A5C746573745C73717561726500007371756172652E6300010000000005020200000001050C0A08BB051406740512740505740204000101 + - Type: CUSTOM + Name: .debug_str + Payload: 636C616E672076657273696F6E2031302E302E302028473A2F4C4C564D31302F6C6C766D2D70726F6A6563742F636C616E6720393338313731623361643737336433366133313362336366626164633730623234323565636133662900673A5C746573745C7371756172655C7371756172652E6300473A5C4C4C564D31305C6C6C766D2D70726F6A6563745C64656275675F7836340073717561726500696E740076616C756500 + - Type: CUSTOM + Name: name + FunctionNames: + - Index: 0 + Name: square + - Type: CUSTOM + Name: producers + Languages: + - Name: C99 + Version: '' + Tools: + - Name: clang + Version: '10.0.0' +... +)"); + + ASSERT_THAT_EXPECTED(ExpectedFile, llvm::Succeeded()); + + ArchSpec arch("wasm32-unknown-unknown-wasm"); + Platform::SetHostPlatform( + platform_gdb_server::PlatformRemoteGDBServer::CreateInstance(true, + &arch)); + + DebuggerSP debugger_sp = Debugger::CreateInstance(); + ASSERT_TRUE(debugger_sp); + + TargetSP target_sp; + PlatformSP platform_sp; + Status error = debugger_sp->GetTargetList().CreateTarget( + *debugger_sp, "", arch, eLoadDependentsNo, platform_sp, target_sp); + ASSERT_TRUE(target_sp); + ASSERT_TRUE(target_sp->GetArchitecture().IsValid()); + ASSERT_TRUE(platform_sp); + + ModuleSpec spec{FileSpec(ExpectedFile->name())}; + auto module_sp = std::make_shared<Module>(spec); + + ObjectFile *object_file = module_sp->GetObjectFile(); + ASSERT_NE(object_file, nullptr); + object_file->SetLoadAddress(*target_sp, 4ULL << 32, false); + + SectionList *list = module_sp->GetSectionList(); + ASSERT_NE(nullptr, list); + + auto code_sp = list->FindSectionByName(ConstString("code")); + ASSERT_NE(nullptr, code_sp); + ASSERT_EQ(0, code_sp->GetFileAddress()); + + auto debug_info_sp = list->FindSectionByName(ConstString(".debug_info")); + ASSERT_NE(nullptr, debug_info_sp); + ASSERT_GT(4ULL << 32, debug_info_sp->GetFileAddress()); + + auto debug_abbrev_sp = list->FindSectionByName(ConstString(".debug_abbrev")); + ASSERT_NE(nullptr, debug_abbrev_sp); + ASSERT_GT(4ULL << 32, debug_abbrev_sp->GetFileAddress()); + + auto debug_line_sp = list->FindSectionByName(ConstString(".debug_line")); + ASSERT_NE(nullptr, debug_line_sp); + ASSERT_GT(4ULL << 32, debug_line_sp->GetFileAddress()); + + auto debug_str_sp = list->FindSectionByName(ConstString(".debug_str")); + ASSERT_NE(nullptr, debug_str_sp); + ASSERT_GT(4ULL << 32, debug_str_sp->GetFileAddress()); +} Index: lldb/unittests/ObjectFile/WASM/CMakeLists.txt =================================================================== --- /dev/null +++ lldb/unittests/ObjectFile/WASM/CMakeLists.txt @@ -0,0 +1,11 @@ +add_lldb_unittest(ObjectFileWasmTests + TestObjectFileWasm.cpp + + LINK_LIBS + lldbUtilityHelpers + LLVMTestingSupport + lldbPluginObjectFileWasm + lldbPluginPlatformGDB + lldbPluginProcessGDBRemote + ) + Index: lldb/unittests/ObjectFile/CMakeLists.txt =================================================================== --- lldb/unittests/ObjectFile/CMakeLists.txt +++ lldb/unittests/ObjectFile/CMakeLists.txt @@ -1,3 +1,4 @@ add_subdirectory(Breakpad) add_subdirectory(ELF) add_subdirectory(PECOFF) +add_subdirectory(WASM) Index: lldb/source/Utility/ArchSpec.cpp =================================================================== --- lldb/source/Utility/ArchSpec.cpp +++ lldb/source/Utility/ArchSpec.cpp @@ -103,10 +103,10 @@ ArchSpec::eCore_arm_arm64, "arm64"}, {eByteOrderLittle, 8, 4, 4, llvm::Triple::aarch64, ArchSpec::eCore_arm_armv8, "armv8"}, - {eByteOrderLittle, 4, 2, 4, llvm::Triple::arm, - ArchSpec::eCore_arm_armv8l, "armv8l"}, + {eByteOrderLittle, 4, 2, 4, llvm::Triple::arm, ArchSpec::eCore_arm_armv8l, + "armv8l"}, {eByteOrderLittle, 4, 4, 4, llvm::Triple::aarch64_32, - ArchSpec::eCore_arm_arm64_32, "arm64_32"}, + ArchSpec::eCore_arm_arm64_32, "arm64_32"}, {eByteOrderLittle, 8, 4, 4, llvm::Triple::aarch64, ArchSpec::eCore_arm_aarch64, "aarch64"}, @@ -220,8 +220,10 @@ ArchSpec::eCore_uknownMach32, "unknown-mach-32"}, {eByteOrderLittle, 8, 4, 4, llvm::Triple::UnknownArch, ArchSpec::eCore_uknownMach64, "unknown-mach-64"}, - {eByteOrderLittle, 4, 2, 4, llvm::Triple::arc, ArchSpec::eCore_arc, "arc"} -}; + {eByteOrderLittle, 4, 2, 4, llvm::Triple::arc, ArchSpec::eCore_arc, "arc"}, + + {eByteOrderLittle, 4, 1, 4, llvm::Triple::wasm32, ArchSpec::eCore_wasm32, + "wasm32"}}; // Ensure that we have an entry in the g_core_definitions for each core. If you // comment out an entry above, you will need to comment out the corresponding @@ -448,7 +450,9 @@ {ArchSpec::eCore_hexagon_generic, llvm::ELF::EM_HEXAGON, LLDB_INVALID_CPUTYPE, 0xFFFFFFFFu, 0xFFFFFFFFu}, // HEXAGON {ArchSpec::eCore_arc, llvm::ELF::EM_ARC_COMPACT2, LLDB_INVALID_CPUTYPE, - 0xFFFFFFFFu, 0xFFFFFFFFu }, // ARC + 0xFFFFFFFFu, 0xFFFFFFFFu}, // ARC + {ArchSpec::eCore_wasm32, llvm::ELF::EM_WASM, LLDB_INVALID_CPUTYPE, + 0xFFFFFFFFu, 0xFFFFFFFFu}, // WebAssembly 32bit }; static const ArchDefinition g_elf_arch_def = { Index: lldb/source/Plugins/SymbolVendor/WASM/SymbolVendorWasm.h =================================================================== --- /dev/null +++ lldb/source/Plugins/SymbolVendor/WASM/SymbolVendorWasm.h @@ -0,0 +1,36 @@ +//===-- SymbolVendorWasm.h ---------------------------------------*- C++ +//-*-===// SymbolVendorWasm +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#ifndef liblldb_SymbolVendorWasm_h_ +#define liblldb_SymbolVendorWasm_h_ + +#include "lldb/Symbol/SymbolVendor.h" +#include "lldb/lldb-private.h" + +class SymbolVendorWasm : public lldb_private::SymbolVendor { +public: + SymbolVendorWasm(const lldb::ModuleSP &module_sp); + + static void Initialize(); + static void Terminate(); + static lldb_private::ConstString GetPluginNameStatic(); + static const char *GetPluginDescriptionStatic(); + + static lldb_private::SymbolVendor * + CreateInstance(const lldb::ModuleSP &module_sp, + lldb_private::Stream *feedback_strm); + + // PluginInterface protocol + lldb_private::ConstString GetPluginName() override; + uint32_t GetPluginVersion() override; + +private: + DISALLOW_COPY_AND_ASSIGN(SymbolVendorWasm); +}; + +#endif // liblldb_SymbolVendorWasm_h_ Index: lldb/source/Plugins/SymbolVendor/WASM/SymbolVendorWasm.cpp =================================================================== --- /dev/null +++ lldb/source/Plugins/SymbolVendor/WASM/SymbolVendorWasm.cpp @@ -0,0 +1,135 @@ +//===-- SymbolVendorWasm.cpp ----------------------------------*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "SymbolVendorWasm.h" + +#include <string.h> + +#include "lldb/Core/Module.h" +#include "lldb/Core/ModuleSpec.h" +#include "lldb/Core/PluginManager.h" +#include "lldb/Core/Section.h" +#include "lldb/Host/Host.h" +#include "lldb/Symbol/LocateSymbolFile.h" +#include "lldb/Symbol/ObjectFile.h" +#include "lldb/Target/Target.h" +#include "lldb/Utility/StreamString.h" +#include "lldb/Utility/Timer.h" + +using namespace lldb; +using namespace lldb_private; + +// SymbolVendorWasm constructor +SymbolVendorWasm::SymbolVendorWasm(const lldb::ModuleSP &module_sp) + : SymbolVendor(module_sp) {} + +void SymbolVendorWasm::Initialize() { + PluginManager::RegisterPlugin(GetPluginNameStatic(), + GetPluginDescriptionStatic(), CreateInstance); +} + +void SymbolVendorWasm::Terminate() { + PluginManager::UnregisterPlugin(CreateInstance); +} + +lldb_private::ConstString SymbolVendorWasm::GetPluginNameStatic() { + static ConstString g_name("WASM"); + return g_name; +} + +const char *SymbolVendorWasm::GetPluginDescriptionStatic() { + return "Symbol vendor for WASM that looks for dwo files that match " + "executables."; +} + +// CreateInstance +// +// Platforms can register a callback to use when creating symbol vendors to +// allow for complex debug information file setups, and to also allow for +// finding separate debug information files. +SymbolVendor * +SymbolVendorWasm::CreateInstance(const lldb::ModuleSP &module_sp, + lldb_private::Stream *feedback_strm) { + if (!module_sp) + return nullptr; + + ObjectFile *obj_file = module_sp->GetObjectFile(); + if (!obj_file) + return nullptr; + + // If the main object file already contains debug info, then we are done. + if (obj_file->GetSectionList()->FindSectionByType( + lldb::eSectionTypeDWARFDebugInfo, true)) + return nullptr; + + static Timer::Category func_cat(LLVM_PRETTY_FUNCTION); + Timer scoped_timer(func_cat, "SymbolVendorWasm::CreateInstance (module = %s)", + module_sp->GetFileSpec().GetPath().c_str()); + + ModuleSpec module_spec; + module_spec.GetFileSpec() = obj_file->GetFileSpec(); + + const FileSpec fspec = module_sp->GetSymbolFileFileSpec(); + + FileSystem::Instance().Resolve(module_spec.GetFileSpec()); + module_spec.GetSymbolFileSpec() = fspec; + module_spec.GetUUID() = obj_file->GetUUID(); + FileSpecList search_paths = Target::GetDefaultDebugFileSearchPaths(); + FileSpec sym_fspec = + Symbols::LocateExecutableSymbolFile(module_spec, search_paths); + if (!sym_fspec) + return nullptr; + + DataBufferSP sym_file_data_sp; + lldb::offset_t sym_file_data_offset = 0; + ObjectFileSP sym_objfile_sp = ObjectFile::FindPlugin( + module_sp, &sym_fspec, 0, FileSystem::Instance().GetByteSize(sym_fspec), + sym_file_data_sp, sym_file_data_offset); + if (!sym_objfile_sp) + return nullptr; + + // This objfile is for debugging purposes. + sym_objfile_sp->SetType(ObjectFile::eTypeDebugInfo); + + SymbolVendorWasm *symbol_vendor = new SymbolVendorWasm(module_sp); + + // Get the module unified section list and add our debug sections to + // that. + SectionList *module_section_list = module_sp->GetSectionList(); + SectionList *objfile_section_list = sym_objfile_sp->GetSectionList(); + + static const SectionType g_sections[] = { + eSectionTypeDWARFDebugAbbrev, eSectionTypeDWARFDebugAddr, + eSectionTypeDWARFDebugAranges, eSectionTypeDWARFDebugCuIndex, + eSectionTypeDWARFDebugFrame, eSectionTypeDWARFDebugInfo, + eSectionTypeDWARFDebugLine, eSectionTypeDWARFDebugLoc, + eSectionTypeDWARFDebugMacInfo, eSectionTypeDWARFDebugPubNames, + eSectionTypeDWARFDebugPubTypes, eSectionTypeDWARFDebugRanges, + eSectionTypeDWARFDebugStr, eSectionTypeDWARFDebugStrOffsets, + eSectionTypeELFSymbolTable, eSectionTypeDWARFGNUDebugAltLink, + }; + for (SectionType section_type : g_sections) { + if (SectionSP section_sp = + objfile_section_list->FindSectionByType(section_type, true)) { + if (SectionSP module_section_sp = + module_section_list->FindSectionByType(section_type, true)) + module_section_list->ReplaceSection(module_section_sp->GetID(), + section_sp); + else + module_section_list->AddSection(section_sp); + } + } + + symbol_vendor->AddSymbolFileRepresentation(sym_objfile_sp); + return symbol_vendor; +} + +// PluginInterface protocol +ConstString SymbolVendorWasm::GetPluginName() { return GetPluginNameStatic(); } + +uint32_t SymbolVendorWasm::GetPluginVersion() { return 1; } Index: lldb/source/Plugins/SymbolVendor/WASM/CMakeLists.txt =================================================================== --- /dev/null +++ lldb/source/Plugins/SymbolVendor/WASM/CMakeLists.txt @@ -0,0 +1,9 @@ +add_lldb_library(lldbPluginSymbolVendorWasm PLUGIN + SymbolVendorWasm.cpp + + LINK_LIBS + lldbCore + lldbHost + lldbSymbol + lldbPluginObjectFileWasm + ) Index: lldb/source/Plugins/SymbolVendor/CMakeLists.txt =================================================================== --- lldb/source/Plugins/SymbolVendor/CMakeLists.txt +++ lldb/source/Plugins/SymbolVendor/CMakeLists.txt @@ -3,3 +3,4 @@ endif() add_subdirectory(ELF) +add_subdirectory(WASM) Index: lldb/source/Plugins/ObjectFile/WASM/ObjectFileWasm.h =================================================================== --- /dev/null +++ lldb/source/Plugins/ObjectFile/WASM/ObjectFileWasm.h @@ -0,0 +1,135 @@ +//===-- ObjectFileWasm.h ---------------------------------- -*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#ifndef LLDB_PLUGINS_OBJECTFILE_WASM_OBJECTFILEWASM_H +#define LLDB_PLUGINS_OBJECTFILE_WASM_OBJECTFILEWASM_H + +#include "lldb/Symbol/ObjectFile.h" +#include "lldb/Utility/ArchSpec.h" + +namespace lldb_private { +namespace wasm { + +class ObjectFileWasm : public ObjectFile { +public: + // Static Functions + static void Initialize(); + static void Terminate(); + + static ConstString GetPluginNameStatic(); + static const char *GetPluginDescriptionStatic() { + return "WebAssembly object file reader."; + } + + static ObjectFile * + CreateInstance(const lldb::ModuleSP &module_sp, lldb::DataBufferSP &data_sp, + lldb::offset_t data_offset, const FileSpec *file, + lldb::offset_t file_offset, lldb::offset_t length); + + static ObjectFile *CreateMemoryInstance(const lldb::ModuleSP &module_sp, + lldb::DataBufferSP &data_sp, + const lldb::ProcessSP &process_sp, + lldb::addr_t header_addr); + + static size_t GetModuleSpecifications(const FileSpec &file, + lldb::DataBufferSP &data_sp, + lldb::offset_t data_offset, + lldb::offset_t file_offset, + lldb::offset_t length, + ModuleSpecList &specs); + + // PluginInterface protocol + ConstString GetPluginName() override { return GetPluginNameStatic(); } + + uint32_t GetPluginVersion() override { return 1; } + + // ObjectFile Protocol. + + bool ParseHeader() override; + + lldb::ByteOrder GetByteOrder() const override { + return m_arch.GetByteOrder(); + } + + bool IsExecutable() const override { return false; } + + uint32_t GetAddressByteSize() const override { + return m_arch.GetAddressByteSize(); + } + + AddressClass GetAddressClass(lldb::addr_t file_addr) override { + return AddressClass::eInvalid; + } + + Symtab *GetSymtab() override; + + bool IsStripped() override { return true; } + + void CreateSections(SectionList &unified_section_list) override; + + void Dump(Stream *s) override; + + ArchSpec GetArchitecture() override { return m_arch; } + + UUID GetUUID() override { return m_uuid; } + + uint32_t GetDependentModules(FileSpecList &files) override { return 0; } + + Type CalculateType() override { return eTypeExecutable; } + + Strata CalculateStrata() override { return eStrataUser; } + + bool SetLoadAddress(lldb_private::Target &target, lldb::addr_t value, + bool value_is_offset) override; + + lldb_private::Address GetBaseAddress() override { + return Address(m_memory_addr + m_code_section_offset); + } + +private: + ObjectFileWasm(const lldb::ModuleSP &module_sp, lldb::DataBufferSP &data_sp, + lldb::offset_t data_offset, const FileSpec *file, + lldb::offset_t offset, lldb::offset_t length); + ObjectFileWasm(const lldb::ModuleSP &module_sp, + lldb::DataBufferSP &header_data_sp, + const lldb::ProcessSP &process_sp, lldb::addr_t header_addr); + + static bool GetVaruint7(DataExtractor §ion_header_data, + lldb::offset_t *offset_ptr, uint8_t *result); + static bool GetVaruint32(DataExtractor §ion_header_data, + lldb::offset_t *offset_ptr, uint32_t *result); + + bool DecodeNextSection(lldb::offset_t *offset_ptr); + bool DecodeSections(lldb::addr_t load_address); + + DataExtractor ReadImageData(uint64_t offset, size_t size); + + typedef struct section_info { + lldb::offset_t offset; + uint32_t size; + uint32_t id; + std::string name; + } section_info_t; + + void DumpSectionHeader(Stream *s, const section_info_t &sh); + void DumpSectionHeaders(Stream *s); + + typedef std::vector<section_info_t> SectionInfoColl; + typedef SectionInfoColl::iterator SectionInfoCollIter; + typedef SectionInfoColl::const_iterator SectionInfoCollConstIter; + SectionInfoColl m_sect_infos; + + ArchSpec m_arch; + UUID m_uuid; + ConstString m_symbols_url; + uint32_t m_code_section_offset; +}; + +} // namespace wasm +} // namespace lldb_private +#endif // LLDB_PLUGINS_OBJECTFILE_WASM_OBJECTFILEWASM_H Index: lldb/source/Plugins/ObjectFile/WASM/ObjectFileWasm.cpp =================================================================== --- /dev/null +++ lldb/source/Plugins/ObjectFile/WASM/ObjectFileWasm.cpp @@ -0,0 +1,486 @@ +//===-- ObjectFileWasm.cpp -------------------------------- -*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "Plugins/ObjectFile/WASM/ObjectFileWasm.h" +#include "lldb/Core/Module.h" +#include "lldb/Core/ModuleSpec.h" +#include "lldb/Core/PluginManager.h" +#include "lldb/Core/Section.h" +#include "lldb/Target/Process.h" +#include "lldb/Target/SectionLoadList.h" +#include "lldb/Target/Target.h" +#include "lldb/Utility/DataBufferHeap.h" +#include "llvm/ADT/ArrayRef.h" +#include "llvm/BinaryFormat/Wasm.h" + +using namespace lldb; +using namespace lldb_private; +using namespace lldb_private::wasm; + +static const uint32_t kWasmHeaderSize = + sizeof(llvm::wasm::WasmMagic) + sizeof(llvm::wasm::WasmVersion); + +bool ValidateModuleHeader(const DataBufferSP &data_sp) { + if (data_sp && data_sp->GetByteSize() > kWasmHeaderSize) { + + const char *magic = reinterpret_cast<const char *>(data_sp->GetBytes()); + if (strncmp(magic, llvm::wasm::WasmMagic, sizeof(llvm::wasm::WasmMagic)) != + 0) { + return false; + } + + const uint32_t *version = reinterpret_cast<const uint32_t *>( + data_sp->GetBytes() + sizeof(llvm::wasm::WasmMagic)); + return *version == llvm::wasm::WasmVersion; + } + return false; +} + +void ObjectFileWasm::Initialize() { + PluginManager::RegisterPlugin(GetPluginNameStatic(), + GetPluginDescriptionStatic(), CreateInstance, + CreateMemoryInstance, GetModuleSpecifications); +} + +void ObjectFileWasm::Terminate() { + PluginManager::UnregisterPlugin(CreateInstance); +} + +ConstString ObjectFileWasm::GetPluginNameStatic() { + static ConstString g_name("wasm"); + return g_name; +} + +ObjectFile * +ObjectFileWasm::CreateInstance(const ModuleSP &module_sp, DataBufferSP &data_sp, + offset_t data_offset, const FileSpec *file, + offset_t file_offset, offset_t length) { + if (!data_sp) { + data_sp = MapFileData(*file, length, file_offset); + if (!data_sp) { + return nullptr; + } + data_offset = 0; + } + + assert(data_sp); + if (!ValidateModuleHeader(data_sp)) { + return nullptr; + } + + // Update the data to contain the entire file if it doesn't already + if (data_sp->GetByteSize() < length) { + data_sp = MapFileData(*file, length, file_offset); + if (!data_sp) { + return nullptr; + } + data_offset = 0; + } + + std::unique_ptr<ObjectFileWasm> objfile_up(new ObjectFileWasm( + module_sp, data_sp, data_offset, file, file_offset, length)); + ArchSpec spec = objfile_up->GetArchitecture(); + if (spec && objfile_up->SetModulesArchitecture(spec)) { + return objfile_up.release(); + } + + return nullptr; +} + +ObjectFile *ObjectFileWasm::CreateMemoryInstance(const ModuleSP &module_sp, + DataBufferSP &data_sp, + const ProcessSP &process_sp, + addr_t header_addr) { + if (ValidateModuleHeader(data_sp)) { + std::unique_ptr<ObjectFileWasm> objfile_up( + new ObjectFileWasm(module_sp, data_sp, process_sp, header_addr)); + ArchSpec spec = objfile_up->GetArchitecture(); + if (spec && objfile_up->SetModulesArchitecture(spec)) { + return objfile_up.release(); + } + } + return nullptr; +} + +// static +bool ObjectFileWasm::GetVaruint7(DataExtractor §ion_header_data, + lldb::offset_t *offset_ptr, uint8_t *result) { + lldb::offset_t initial_offset = *offset_ptr; + uint64_t value = section_header_data.GetULEB128(offset_ptr); + if (*offset_ptr == initial_offset || value > 127) { + return false; + } + *result = static_cast<uint8_t>(value); + return true; +} + +// static +bool ObjectFileWasm::GetVaruint32(DataExtractor §ion_header_data, + lldb::offset_t *offset_ptr, + uint32_t *result) { + lldb::offset_t initial_offset = *offset_ptr; + uint64_t value = section_header_data.GetULEB128(offset_ptr); + if (*offset_ptr == initial_offset || value > uint64_t(1) << 32) { + return false; + } + *result = static_cast<uint32_t>(value); + return true; +} + +bool ObjectFileWasm::DecodeNextSection(lldb::offset_t *offset_ptr) { + static ConstString g_sect_name_external_debug_info("external_debug_info"); + + // Buffer sufficient to read a section header and find the pointer to the next + // section. + const uint32_t kBufferSize = 1024; + DataExtractor section_header_data = ReadImageData(*offset_ptr, kBufferSize); + + lldb::offset_t offset = 0; + uint8_t section_id = 0; + uint32_t payload_len = 0; + // Each section consists of: + // - a one-byte section id, + // - the u32 size of the contents, in bytes, + // - the actual contents. + if (GetVaruint7(section_header_data, &offset, §ion_id) && + GetVaruint32(section_header_data, &offset, &payload_len)) { + + if (section_id == 0) { + // Custom sections have the id 0. Their contents consist of a name + // identifying the custom section, followed by an uninterpreted sequence + // of bytes. + // The name is encoded as a vector of UTF-8 codes. + // Vectors are encoded with their u32 length followed by the element + // sequence. + uint32_t name_len = 0; + lldb::offset_t prev_offset = offset; + if (GetVaruint32(section_header_data, &offset, &name_len)) { + uint32_t name_len_uleb_size = offset - prev_offset; + + const uint8_t *name_bytes = + section_header_data.PeekData(offset, name_len); + if (!name_bytes) { + // If a custom section has a name longer than the allocated buffer or + // longer than the data left in the image, ignore this section. + return false; + } + std::string sect_name(reinterpret_cast<const char *>(name_bytes), + name_len); + offset += name_len; + + if (g_sect_name_external_debug_info == sect_name.c_str()) { + // A Wasm file that has external DWARF debug information should + // contains a custom section named "external_debug_info", whose + // payload is an UTF-8 encoded URL string that points to the external + // DWARF file. + uint32_t url_len = 0; + prev_offset = offset; + if (GetVaruint32(section_header_data, &offset, &url_len)) { + uint32_t url_len_uleb_size = offset - prev_offset; + + const uint8_t *url_bytes = + section_header_data.PeekData(offset, url_len); + if (!url_bytes) { + return false; + } + m_symbols_url = + ConstString(reinterpret_cast<const char *>(url_bytes), url_len); + FileSpec file_spec(m_symbols_url.GetStringRef()); + GetModule()->SetSymbolFileFileSpec(FileSpec(file_spec)); + + uint32_t section_length = + payload_len - name_len - name_len_uleb_size - url_len_uleb_size; + offset += section_length; + } + } else { + uint32_t section_length = payload_len - name_len - name_len_uleb_size; + m_sect_infos.push_back(section_info{ + *offset_ptr + offset, section_length, section_id, sect_name}); + offset += section_length; + } + } + } else if (section_id <= llvm::wasm::WASM_SEC_EVENT) { + m_sect_infos.push_back( + section_info{*offset_ptr + offset, payload_len, section_id, ""}); + offset += payload_len; + } else { + // Invalid section id + return false; + } + *offset_ptr += offset; + return true; + } + return false; +} + +bool ObjectFileWasm::DecodeSections(lldb::addr_t load_address) { + lldb::offset_t offset = load_address + kWasmHeaderSize; + while (DecodeNextSection(&offset)) + ; + return true; +} + +size_t ObjectFileWasm::GetModuleSpecifications( + const FileSpec &file, DataBufferSP &data_sp, offset_t data_offset, + offset_t file_offset, offset_t length, ModuleSpecList &specs) { + if (!ValidateModuleHeader(data_sp)) { + return 0; + } + + ModuleSpec spec(file, ArchSpec("wasm32-unknown-unknown-wasm")); + specs.Append(spec); + return 1; +} + +ObjectFileWasm::ObjectFileWasm(const ModuleSP &module_sp, DataBufferSP &data_sp, + offset_t data_offset, const FileSpec *file, + offset_t offset, offset_t length) + : ObjectFile(module_sp, file, offset, length, data_sp, data_offset), + m_arch("wasm32-unknown-unknown-wasm"), m_code_section_offset(0) { + m_data.SetAddressByteSize(4); +} + +ObjectFileWasm::ObjectFileWasm(const lldb::ModuleSP &module_sp, + lldb::DataBufferSP &header_data_sp, + const lldb::ProcessSP &process_sp, + lldb::addr_t header_addr) + : ObjectFile(module_sp, process_sp, header_addr, header_data_sp), + m_arch("wasm32-unknown-unknown-wasm"), m_code_section_offset(0) {} + +bool ObjectFileWasm::ParseHeader() { + // We already parsed the header during initialization. + return true; +} + +Symtab *ObjectFileWasm::GetSymtab() { return nullptr; } + +void ObjectFileWasm::CreateSections(SectionList &unified_section_list) { + static ConstString g_sect_name_dwarf_debug_abbrev(".debug_abbrev"); + static ConstString g_sect_name_dwarf_debug_aranges(".debug_aranges"); + static ConstString g_sect_name_dwarf_debug_frame(".debug_frame"); + static ConstString g_sect_name_dwarf_debug_info(".debug_info"); + static ConstString g_sect_name_dwarf_debug_line(".debug_line"); + static ConstString g_sect_name_dwarf_debug_loc(".debug_loc"); + static ConstString g_sect_name_dwarf_debug_loclists(".debug_loclists"); + static ConstString g_sect_name_dwarf_debug_macinfo(".debug_macinfo"); + static ConstString g_sect_name_dwarf_debug_names(".debug_names"); + static ConstString g_sect_name_dwarf_debug_pubnames(".debug_pubnames"); + static ConstString g_sect_name_dwarf_debug_pubtypes(".debug_pubtypes"); + static ConstString g_sect_name_dwarf_debug_ranges(".debug_ranges"); + static ConstString g_sect_name_dwarf_debug_str(".debug_str"); + static ConstString g_sect_name_dwarf_debug_types(".debug_types"); + static ConstString g_sect_name_dwarf_debug_addr("dwarf-addr"); + static ConstString g_sect_name_dwarf_debug_cuindex("dwarf-cu-index"); + static ConstString g_sect_name_dwarf_debug_macro("dwarf-macro"); + static ConstString g_sect_name_dwarf_debug_stroffsets("dwarf-str-offsets"); + + if (m_sections_up) + return; + + m_sections_up = std::make_unique<SectionList>(); + + if (m_sect_infos.empty()) { + DecodeSections(0); + } + + for (SectionInfoCollConstIter it = m_sect_infos.begin(); + it != m_sect_infos.end(); ++it) { + const section_info §_info = *it; + + SectionType section_type = eSectionTypeInvalid; + + if (llvm::wasm::WASM_SEC_CODE == sect_info.id) + section_type = eSectionTypeCode; + else if (g_sect_name_dwarf_debug_abbrev == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugAbbrev; + else if (g_sect_name_dwarf_debug_aranges == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugAranges; + else if (g_sect_name_dwarf_debug_frame == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugFrame; + else if (g_sect_name_dwarf_debug_info == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugInfo; + else if (g_sect_name_dwarf_debug_line == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugLine; + else if (g_sect_name_dwarf_debug_loc == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugLoc; + else if (g_sect_name_dwarf_debug_loclists == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugLocLists; + else if (g_sect_name_dwarf_debug_macinfo == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugMacInfo; + else if (g_sect_name_dwarf_debug_names == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugNames; + else if (g_sect_name_dwarf_debug_pubnames == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugPubNames; + else if (g_sect_name_dwarf_debug_pubtypes == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugPubTypes; + else if (g_sect_name_dwarf_debug_ranges == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugRanges; + else if (g_sect_name_dwarf_debug_str == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugStr; + else if (g_sect_name_dwarf_debug_types == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugTypes; + else if (g_sect_name_dwarf_debug_addr == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugAddr; + else if (g_sect_name_dwarf_debug_cuindex == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugCuIndex; + else if (g_sect_name_dwarf_debug_macro == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugMacro; + else if (g_sect_name_dwarf_debug_stroffsets == sect_info.name.c_str()) + section_type = eSectionTypeDWARFDebugStrOffsets; + + if (section_type == eSectionTypeCode) { + m_code_section_offset = sect_info.offset & 0xffffffff; + SectionSP section_sp( + new Section(GetModule(), // Module to which this section belongs. + this, // ObjectFile to which this section belongs and + // should read section data from. + section_type, // Section ID. + ConstString("code"), // Section name. + section_type, // Section type. + 0, // sect_info.offset & 0xffffffff, // VM address. + sect_info.size, // VM size in bytes of this section. + 0, // sect_info.offset & 0xffffffff, // Offset of this + // section in the file. + sect_info.size, // Size of the section as found in + // the file. + 0, // Alignment of the section + 0, // Flags for this section. + 1)); // Number of host bytes per target byte + m_sections_up->AddSection(section_sp); + } else if (section_type != eSectionTypeInvalid) { + SectionSP section_sp(new Section( + GetModule(), // Module to which this section belongs. + this, // ObjectFile to which this section belongs and + // should read section data from. + section_type, // Section ID. + ConstString(sect_info.name.c_str()), // Section name. + section_type, // Section type. + sect_info.offset & 0xffffffff, // VM address. + sect_info.size, // VM size in bytes of this section. + sect_info.offset & 0xffffffff, // Offset of this section in the file. + sect_info.size, // Size of the section as found in + // the file. + 0, // Alignment of the section + 0, // Flags for this section. + 1)); // Number of host bytes per target byte + m_sections_up->AddSection(section_sp); + } + } + + for (const auto §ion : *m_sections_up) { + unified_section_list.AddSection(section); + } +} + +// In WebAssembly, linear memory is disjointed from code space. The VM can load +// multiple instances of a module, which logically share the same code. +// We represent a wasm32 code address with 64-bits, like: +// 63 32 31 0 +// +---------------+---------------+ +// + module_id | offset | +// +---------------+---------------+ +// where the lower 32 bits represent a module offset (relative to the module +// start not to the beginning of the code section) and the higher 32 bits +// uniquely identify the module in the WebAssembly VM. +// In other words, we assume that each WebAssembly module is loaded by the +// engine at a 64-bit address that starts at the boundary of 4GB pages, like +// 0x0000000400000000 for module_id == 4. +// These 64-bit addresses will be used to request code ranges for a specific +// module from the WebAssembly engine. + +bool ObjectFileWasm::SetLoadAddress(Target &target, lldb::addr_t load_address, + bool value_is_offset) { + ModuleSP module_sp = GetModule(); + if (module_sp) { + DecodeSections(load_address); + + size_t num_loaded_sections = 0; + SectionList *section_list = GetSectionList(); + if (section_list) { + const size_t num_sections = section_list->GetSize(); + size_t sect_idx = 0; + + for (sect_idx = 0; sect_idx < num_sections; ++sect_idx) { + SectionSP section_sp(section_list->GetSectionAtIndex(sect_idx)); + if (target.GetSectionLoadList().SetSectionLoadAddress( + section_sp, load_address | section_sp->GetFileOffset())) { + ++num_loaded_sections; + } + } + return num_loaded_sections > 0; + } + } + return false; +} + +DataExtractor ObjectFileWasm::ReadImageData(uint64_t offset, size_t size) { + DataExtractor data; + if (m_file) { + if (offset < GetByteSize()) { + size = std::min(size, GetByteSize() - offset); + auto buffer_sp = MapFileData(m_file, size, offset); + return DataExtractor(buffer_sp, GetByteOrder(), GetAddressByteSize()); + } + } else { + ProcessSP process_sp(m_process_wp.lock()); + if (process_sp) { + auto data_up = std::make_unique<DataBufferHeap>(size, 0); + Status readmem_error; + size_t bytes_read = process_sp->ReadMemory( + offset, data_up->GetBytes(), data_up->GetByteSize(), readmem_error); + if (bytes_read > 0) { + DataBufferSP buffer_sp(data_up.release()); + data.SetData(buffer_sp, 0, buffer_sp->GetByteSize()); + } + } + } + return data; +} + +void ObjectFileWasm::Dump(Stream *s) { + ModuleSP module_sp(GetModule()); + if (module_sp) { + std::lock_guard<std::recursive_mutex> guard(module_sp->GetMutex()); + s->Printf("%p: ", static_cast<void *>(this)); + s->Indent(); + s->PutCString("ObjectFileWasm"); + + ArchSpec header_arch = GetArchitecture(); + + *s << ", file = '" << m_file + << "', arch = " << header_arch.GetArchitectureName() << "\n"; + + SectionList *sections = GetSectionList(); + if (sections) { + sections->Dump(s, nullptr, true, UINT32_MAX); + } + s->EOL(); + DumpSectionHeaders(s); + s->EOL(); + } +} + +// Dump a single Wasm section header to the specified output stream. +void ObjectFileWasm::DumpSectionHeader(Stream *s, const section_info_t &sh) { + s->Printf("%-16s 0x%8.8x 0x%8.8x 0x%4.4x\n", sh.name.c_str(), sh.offset, + sh.size, sh.id); +} + +// Dump all of the Wasm section header to the specified output stream. +void ObjectFileWasm::DumpSectionHeaders(Stream *s) { + s->PutCString("Section Headers\n"); + s->PutCString("IDX name addr size id\n"); + s->PutCString("==== ---------------- ---------- ---------- ------\n"); + + uint32_t idx = 0; + SectionInfoCollIter pos, end = m_sect_infos.end(); + for (pos = m_sect_infos.begin(); pos != end; ++pos, ++idx) { + s->Printf("[%2u] ", idx); + ObjectFileWasm::DumpSectionHeader(s, *pos); + } +} Index: lldb/source/Plugins/ObjectFile/WASM/CMakeLists.txt =================================================================== --- /dev/null +++ lldb/source/Plugins/ObjectFile/WASM/CMakeLists.txt @@ -0,0 +1,11 @@ +add_lldb_library(lldbPluginObjectFileWasm PLUGIN + ObjectFileWasm.cpp + + LINK_LIBS + lldbCore + lldbHost + lldbSymbol + lldbUtility + LINK_COMPONENTS + Support + ) Index: lldb/source/Plugins/ObjectFile/CMakeLists.txt =================================================================== --- lldb/source/Plugins/ObjectFile/CMakeLists.txt +++ lldb/source/Plugins/ObjectFile/CMakeLists.txt @@ -3,3 +3,4 @@ add_subdirectory(Mach-O) add_subdirectory(PECOFF) add_subdirectory(JIT) +add_subdirectory(WASM) Index: lldb/source/Plugins/DynamicLoader/WASM-DYLD/DynamicLoaderWasmDYLD.h =================================================================== --- /dev/null +++ lldb/source/Plugins/DynamicLoader/WASM-DYLD/DynamicLoaderWasmDYLD.h @@ -0,0 +1,51 @@ +//===-- DynamicLoaderWasmDYLD.h ------------------------------*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#ifndef liblldb_Plugins_Process_Wasm_DynamicLoaderWasmDYLD_h_ +#define liblldb_Plugins_Process_Wasm_DynamicLoaderWasmDYLD_h_ + +#include "lldb/Target/DynamicLoader.h" +#include "lldb/lldb-forward.h" + +#include <map> + +namespace lldb_private { + +class DynamicLoaderWasmDYLD : public DynamicLoader { +public: + DynamicLoaderWasmDYLD(Process *process); + + ~DynamicLoaderWasmDYLD() override; + + static void Initialize(); + static void Terminate(); + static ConstString GetPluginNameStatic(); + static const char *GetPluginDescriptionStatic(); + + static DynamicLoader *CreateInstance(Process *process, bool force); + + lldb::ModuleSP LoadModuleAtAddress(const lldb_private::FileSpec &file, + lldb::addr_t link_map_addr, + lldb::addr_t base_addr, + bool base_addr_is_offset) override; + void DidAttach() override; + void DidLaunch() override; + Status CanLoadImage() override; + lldb::ThreadPlanSP GetStepThroughTrampolinePlan(Thread &thread, + bool stop) override; + + ConstString GetPluginName() override; + uint32_t GetPluginVersion() override; + +private: + std::map<lldb::ModuleSP, lldb::addr_t> m_loaded_modules; +}; + +} // namespace lldb_private + +#endif // liblldb_Plugins_Process_Wasm_DynamicLoaderWasmDYLD_h_ Index: lldb/source/Plugins/DynamicLoader/WASM-DYLD/DynamicLoaderWasmDYLD.cpp =================================================================== --- /dev/null +++ lldb/source/Plugins/DynamicLoader/WASM-DYLD/DynamicLoaderWasmDYLD.cpp @@ -0,0 +1,177 @@ +//===-- DynamicLoaderWasmDYLD.cpp --------------------------------*- C++ +//-*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "DynamicLoaderWasmDYLD.h" + +#include "lldb/Core/Module.h" +#include "lldb/Core/PluginManager.h" +#include "lldb/Core/Section.h" +#include "lldb/Symbol/ObjectFile.h" +#include "lldb/Target/Process.h" +#include "lldb/Target/RegisterContext.h" +#include "lldb/Target/Target.h" +#include "lldb/Target/ThreadPlanStepInstruction.h" +#include "lldb/Utility/Log.h" +#include "llvm/ADT/Triple.h" + +using namespace lldb; +using namespace lldb_private; + +DynamicLoaderWasmDYLD::DynamicLoaderWasmDYLD(Process *process) + : DynamicLoader(process) {} + +DynamicLoaderWasmDYLD::~DynamicLoaderWasmDYLD() {} + +void DynamicLoaderWasmDYLD::Initialize() { + PluginManager::RegisterPlugin(GetPluginNameStatic(), + GetPluginDescriptionStatic(), CreateInstance); +} + +void DynamicLoaderWasmDYLD::Terminate() {} + +ConstString DynamicLoaderWasmDYLD::GetPluginNameStatic() { + static ConstString g_plugin_name("wasm-dyld"); + return g_plugin_name; +} + +const char *DynamicLoaderWasmDYLD::GetPluginDescriptionStatic() { + return "Dynamic loader plug-in that watches for shared library " + "loads/unloads in WebAssembly engines."; +} + +DynamicLoader *DynamicLoaderWasmDYLD::CreateInstance(Process *process, + bool force) { + bool should_create = force; + if (!should_create) { + const llvm::Triple &triple_ref = + process->GetTarget().GetArchitecture().GetTriple(); + if (triple_ref.getArch() == llvm::Triple::wasm32) + should_create = true; + } + + if (should_create) + return new DynamicLoaderWasmDYLD(process); + + return nullptr; +} + +// In WebAssembly, linear memory is disjointed from code space. The VM can load +// multiple instances of a module, which logically share the same code. +// Currently we only support wasm32, which uses a 32-bit address space for the +// code. +// We represent a code address in LLDB as a 64-bit address with the format: +// 63 32 31 0 +// +---------------+---------------+ +// + module_id | offset | +// +---------------+---------------+ +// where the lower 32 bits represent a module offset (relative to the module +// start not to the beginning of the code section) and the higher 32 bits +// uniquely identify the module in the WebAssembly VM. +// This method should be called for each Wasm module loaded in the debuggee, +// with base_addr = 0x{module_id}|00000000 (for example 0x0000000100000000). + +ModuleSP DynamicLoaderWasmDYLD::LoadModuleAtAddress(const FileSpec &file, + addr_t link_map_addr, + addr_t base_addr, + bool base_addr_is_offset) { + Target &target = m_process->GetTarget(); + ModuleList &modules = target.GetImages(); + ModuleSpec module_spec(file, target.GetArchitecture()); + ModuleSP module_sp; + + if ((module_sp = modules.FindFirstModule(module_spec))) { + UpdateLoadedSections(module_sp, link_map_addr, base_addr, + base_addr_is_offset); + return module_sp; + } + + if ((module_sp = m_process->ReadModuleFromMemory(file, base_addr))) { + UpdateLoadedSections(module_sp, link_map_addr, base_addr, false); + target.GetImages().AppendIfNeeded(module_sp); + } + + return module_sp; +} + +void DynamicLoaderWasmDYLD::DidAttach() { + Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER)); + LLDB_LOGF(log, "DynamicLoaderWasmDYLD::%s()", __FUNCTION__); + + // Ask the process for the list of loaded WebAssembly modules. + auto error = m_process->LoadModules(); + LLDB_LOG_ERROR(log, std::move(error), "Couldn't load modules: {0}"); + + ModuleList loaded_module_list; + const ModuleList &module_list = m_process->GetTarget().GetImages(); + const size_t num_modules = module_list.GetSize(); + for (uint32_t idx = 0; idx < num_modules; ++idx) { + ModuleSP module_sp(module_list.GetModuleAtIndexUnlocked(idx)); + ObjectFile *image_object_file = module_sp->GetObjectFile(); + lldb::addr_t code_load_address = + image_object_file->GetBaseAddress().GetOffset(); + lldb::addr_t image_load_address = + image_object_file->GetBaseAddress().GetOffset() & 0xffffffff00000000; + if (module_sp) { + bool changed = false; + if (image_object_file) { + SectionList *section_list = image_object_file->GetSectionList(); + if (section_list) { + // Fixes the section load address for each section. + const size_t num_sections = section_list->GetSize(); + for (size_t sect_idx = 0; sect_idx < num_sections; ++sect_idx) { + SectionSP section_sp(section_list->GetSectionAtIndex(sect_idx)); + if (section_sp) { + // Code section load address is offsetted by the code section + // offset in the Wasm module. + if (section_sp->GetName() == "code") { + if (m_process->GetTarget().SetSectionLoadAddress( + section_sp, + code_load_address | section_sp->GetFileAddress())) { + changed = true; + } + } else { + if (m_process->GetTarget().SetSectionLoadAddress( + section_sp, + image_load_address | section_sp->GetFileAddress())) { + changed = true; + } + } + } + } + } + } + + if (changed) + loaded_module_list.AppendIfNeeded(module_sp); + } + } + + m_process->GetTarget().ModulesDidLoad(loaded_module_list); +} + +void DynamicLoaderWasmDYLD::DidLaunch() {} + +Status DynamicLoaderWasmDYLD::CanLoadImage() { return Status(); } + +ConstString DynamicLoaderWasmDYLD::GetPluginName() { + return GetPluginNameStatic(); +} + +uint32_t DynamicLoaderWasmDYLD::GetPluginVersion() { return 1; } + +ThreadPlanSP DynamicLoaderWasmDYLD::GetStepThroughTrampolinePlan(Thread &thread, + bool stop) { + auto arch = m_process->GetTarget().GetArchitecture(); + if (arch.GetMachine() != llvm::Triple::wasm32) { + return ThreadPlanSP(); + } + + // TODO(paolosev) - What should we do here? + return ThreadPlanSP(); +} Index: lldb/source/Plugins/DynamicLoader/WASM-DYLD/CMakeLists.txt =================================================================== --- /dev/null +++ lldb/source/Plugins/DynamicLoader/WASM-DYLD/CMakeLists.txt @@ -0,0 +1,9 @@ +add_lldb_library(lldbPluginDynamicLoaderWasmDYLD PLUGIN + DynamicLoaderWasmDYLD.cpp + + LINK_LIBS + lldbCore + lldbTarget + LINK_COMPONENTS + Support + ) Index: lldb/source/Plugins/DynamicLoader/CMakeLists.txt =================================================================== --- lldb/source/Plugins/DynamicLoader/CMakeLists.txt +++ lldb/source/Plugins/DynamicLoader/CMakeLists.txt @@ -4,3 +4,4 @@ add_subdirectory(Static) add_subdirectory(Hexagon-DYLD) add_subdirectory(Windows-DYLD) +add_subdirectory(WASM-DYLD) \ No newline at end of file Index: lldb/source/API/SystemInitializerFull.cpp =================================================================== --- lldb/source/API/SystemInitializerFull.cpp +++ lldb/source/API/SystemInitializerFull.cpp @@ -44,6 +44,7 @@ #include "Plugins/DynamicLoader/MacOSX-DYLD/DynamicLoaderMacOSXDYLD.h" #include "Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.h" #include "Plugins/DynamicLoader/Static/DynamicLoaderStatic.h" +#include "Plugins/DynamicLoader/WASM-DYLD/DynamicLoaderWasmDYLD.h" #include "Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.h" #include "Plugins/Instruction/ARM/EmulateInstructionARM.h" #include "Plugins/Instruction/ARM64/EmulateInstructionARM64.h" @@ -69,6 +70,7 @@ #include "Plugins/ObjectFile/ELF/ObjectFileELF.h" #include "Plugins/ObjectFile/Mach-O/ObjectFileMachO.h" #include "Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.h" +#include "Plugins/ObjectFile/WASM/ObjectFileWasm.h" #include "Plugins/OperatingSystem/Python/OperatingSystemPython.h" #include "Plugins/Platform/Android/PlatformAndroid.h" #include "Plugins/Platform/FreeBSD/PlatformFreeBSD.h" @@ -90,6 +92,7 @@ #include "Plugins/SymbolFile/PDB/SymbolFilePDB.h" #include "Plugins/SymbolFile/Symtab/SymbolFileSymtab.h" #include "Plugins/SymbolVendor/ELF/SymbolVendorELF.h" +#include "Plugins/SymbolVendor/WASM/SymbolVendorWasm.h" #include "Plugins/SystemRuntime/MacOSX/SystemRuntimeMacOSX.h" #include "Plugins/UnwindAssembly/InstEmulation/UnwindAssemblyInstEmulation.h" #include "Plugins/UnwindAssembly/x86/UnwindAssembly-x86.h" @@ -173,6 +176,7 @@ ObjectFileELF::Initialize(); ObjectFileMachO::Initialize(); ObjectFilePECOFF::Initialize(); + wasm::ObjectFileWasm::Initialize(); ObjectContainerBSDArchive::Initialize(); ObjectContainerUniversalMachO::Initialize(); @@ -232,6 +236,7 @@ SymbolFileDWARF::Initialize(); SymbolFilePDB::Initialize(); SymbolFileSymtab::Initialize(); + SymbolVendorWasm::Initialize(); UnwindAssemblyInstEmulation::Initialize(); UnwindAssembly_x86::Initialize(); @@ -280,6 +285,7 @@ DynamicLoaderMacOSXDYLD::Initialize(); DynamicLoaderMacOS::Initialize(); DynamicLoaderPOSIXDYLD::Initialize(); + DynamicLoaderWasmDYLD::Initialize(); DynamicLoaderStatic::Initialize(); DynamicLoaderWindowsDYLD::Initialize(); @@ -324,6 +330,7 @@ ThreadSanitizerRuntime::Terminate(); UndefinedBehaviorSanitizerRuntime::Terminate(); MainThreadCheckerRuntime::Terminate(); + SymbolVendorWasm::Terminate(); SymbolVendorELF::Terminate(); breakpad::SymbolFileBreakpad::Terminate(); SymbolFileDWARF::Terminate(); @@ -372,6 +379,7 @@ DynamicLoaderMacOSXDYLD::Terminate(); DynamicLoaderMacOS::Terminate(); DynamicLoaderPOSIXDYLD::Terminate(); + DynamicLoaderWasmDYLD::Terminate(); DynamicLoaderStatic::Terminate(); DynamicLoaderWindowsDYLD::Terminate(); @@ -396,6 +404,7 @@ ObjectFileELF::Terminate(); ObjectFileMachO::Terminate(); ObjectFilePECOFF::Terminate(); + wasm::ObjectFileWasm::Terminate(); ObjectContainerBSDArchive::Terminate(); ObjectContainerUniversalMachO::Terminate(); Index: lldb/include/lldb/Utility/ArchSpec.h =================================================================== --- lldb/include/lldb/Utility/ArchSpec.h +++ lldb/include/lldb/Utility/ArchSpec.h @@ -188,6 +188,7 @@ eCore_arc, // little endian ARC + eCore_wasm32, kNumCores, kCore_invalid,
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