diff options
| author | _ov4 <ov4@ov4.org> | 2026-10-19 13:21:24 +0000 |
|---|---|---|
| committer | _ov4 <ov4@ov4.org> | 2026-10-19 13:21:24 +0000 |
| commit | f01cafc0ead695e8c5280e5e4a942b24e1922e13 (patch) | |
| tree | 431d4063f5ab5d78e44db4b02f0747f7b3b94432 /tools | |
| parent | 2157f7e4043a0742cac19d3ae62f6b836c14516f (diff) | |
refactor(driver): isolate MinGW JIT compatibility support
Move COFF normalization, jump stubs and SEH registration behind two
internal entry points. Keep runtime bindings in the embedded runner,
remove redundant conditions and document the upstream requirements.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/driver/EmbeddedRunner.cc | 335 | ||||
| -rw-r--r-- | tools/driver/MinGWCOFF.h | 138 | ||||
| -rw-r--r-- | tools/driver/MinGWJIT.cc | 447 | ||||
| -rw-r--r-- | tools/driver/MinGWJIT.h | 25 |
4 files changed, 476 insertions, 469 deletions
diff --git a/tools/driver/EmbeddedRunner.cc b/tools/driver/EmbeddedRunner.cc index 49375e1..587d664 100644 --- a/tools/driver/EmbeddedRunner.cc +++ b/tools/driver/EmbeddedRunner.cc @@ -1,11 +1,11 @@ #include "EmbeddedRunner.h" +#include "MinGWJIT.h" #include "NativeCompiler.h" #include "llvm/Object/ObjectFile.h" #include "cps/CodeGen.h" #include "llvm/ExecutionEngine/Orc/AbsoluteSymbols.h" #include "llvm/ExecutionEngine/Orc/ExecutionUtils.h" #include "llvm/ExecutionEngine/Orc/LLJIT.h" -#include "llvm/ExecutionEngine/Orc/ObjectFileInterface.h" #include "llvm/ExecutionEngine/Orc/ObjectLinkingLayer.h" #include "llvm/ExecutionEngine/Orc/ThreadSafeModule.h" #include "llvm/Support/Error.h" @@ -17,323 +17,12 @@ #include <cxxabi.h> #include <typeinfo> #include <unwind.h> -#if defined(_WIN32) && defined(__x86_64__) -#ifndef NOMINMAX -#define NOMINMAX -#endif -#include <algorithm> -#include <cstring> -#include <limits> -#include "llvm/ExecutionEngine/JITLink/JITLink.h" -#include "llvm/ExecutionEngine/JITLink/x86_64.h" -#include "llvm/ExecutionEngine/Orc/LinkGraphLinkingLayer.h" -#include "llvm/ExecutionEngine/Orc/Shared/WrapperFunctionUtils.h" -#include "llvm/Support/Endian.h" -#include "MinGWCOFF.h" -// Windows IMAGE_* macros conflict with LLVM COFF enums and inline helpers. -// Parse all LLVM COFF declarations and helpers before introducing those macros. -#include <windows.h> -#endif #ifdef __MINGW32__ #include <io.h> #endif namespace { -#if defined(_WIN32) && defined(__x86_64__) -// In-process COFF/SEH support for the MinGW x86_64 JIT. -// -// The full upstream COFFPlatform starts the VC runtime loading machinery, -// which does not apply to the current MinGW build. This plugin provides only -// the linking and registration pieces needed for in-process execution: -// a per-graph __ImageBase shared by relocations and SEH registration, -// JITLink stubs for external direct branches and GNU personalities in .xdata, -// and RtlAddFunctionTable/RtlDeleteFunctionTable via JITLink allocation -// actions. Exception propagation still uses the existing C++ ABI, LLVM -// exception instructions and platform unwinder. - -static constexpr llvm::StringLiteral COFFSEHTableSection = "$__cpsc_seh"; - -static llvm::Error addCOFFJumpStubs(llvm::jitlink::LinkGraph &G) { - using namespace llvm; - using namespace llvm::jitlink; - using namespace llvm::jitlink::x86_64; - GOTTableManager GOT(G); - PLTTableManager PLT(G, GOT); - // Creating a stub may add sections/blocks. Visit only the original blocks. - std::vector<Block *> Blocks(G.blocks().begin(), G.blocks().end()); - for (auto *B : Blocks) { - bool Executable = (B->getSection().getMemProt() & orc::MemProt::Exec) != - orc::MemProt::None; - for (auto &E : B->edges()) { - Symbol &Target = E.getTarget(); - if (!Target.isExternal()) - continue; - bool Personality = false; - if (isCOFFUnwindSection(B->getSection().getName(), ".xdata") && - Target.hasName()) { - StringRef Name = *Target.getName(); - Personality = Name == "__gxx_personality_seh0" || - Name == "__gxx_personality_sj0" || - Name == "__gxx_personality_v0"; - } - // COFF's private PCRel32 kind is lowered only in PreFixup. - // Use its name rather than confusing it with x86_64::PCRel32. - // Only E8/E9 direct branches with a plain symbol target need a - // jump stub; RIP-relative data and indirect calls must stay intact. - bool DirectBranch = false; - if (Executable && !B->isZeroFill() && E.getAddend() == 0 && - StringRef(G.getEdgeKindName(E.getKind())) == "PCRel32") { - auto Content = B->getContent(); - size_t Offset = E.getOffset(); - if (Offset > 0 && Offset <= Content.size() && - Content.size() - Offset >= 4) { - unsigned char Opcode = Content[Offset - 1]; - DirectBranch = Opcode == 0xe8 || Opcode == 0xe9; - } - } - if (Personality || DirectBranch) - E.setTarget(PLT.getEntryForTarget(G, Target)); - } - } - return Error::success(); -} - -static llvm::Error registerSEHTable(llvm::orc::ExecutorAddrRange TableRange, - llvm::orc::ExecutorAddr ImageBase) { - using llvm::make_error; - using llvm::StringError; - using llvm::inconvertibleErrorCode; - size_t Size = TableRange.size(); - if (Size == 0 || ImageBase.isNull()) - return make_error<StringError>("invalid embedded SEH function table", - inconvertibleErrorCode()); - if (Size % sizeof(RUNTIME_FUNCTION)) - return make_error<StringError>("invalid embedded SEH function table", - inconvertibleErrorCode()); - uint64_t Count64 = Size / sizeof(RUNTIME_FUNCTION); - if (Count64 == 0 || Count64 > static_cast<uint64_t>(std::numeric_limits<DWORD>::max())) - return make_error<StringError>("invalid embedded SEH function table", - inconvertibleErrorCode()); - auto *Table = TableRange.Start.toPtr<const RUNTIME_FUNCTION *>(); - DWORD PrevBegin = 0; - for (uint64_t I = 0; I < Count64; ++I) { - DWORD Begin = llvm::support::endian::read32le( - reinterpret_cast<const char *>(Table + I) + 0); - DWORD End = llvm::support::endian::read32le( - reinterpret_cast<const char *>(Table + I) + 4); - if (!(Begin < End)) - return make_error<StringError>("invalid embedded SEH function table", - inconvertibleErrorCode()); - if (I > 0 && !(PrevBegin < Begin)) - return make_error<StringError>("invalid embedded SEH function table", - inconvertibleErrorCode()); - PrevBegin = Begin; - } - auto *MutableTable = const_cast<PRUNTIME_FUNCTION>(Table); - DWORD Count = static_cast<DWORD>(Count64); - DWORD64 Base = static_cast<DWORD64>(ImageBase.getValue()); - if (!RtlAddFunctionTable(MutableTable, Count, Base)) - return make_error<StringError>("cannot register embedded SEH function table", - inconvertibleErrorCode()); - return llvm::Error::success(); -} - -static llvm::Error deregisterSEHTable(llvm::orc::ExecutorAddrRange TableRange, - llvm::orc::ExecutorAddr ImageBase) { - (void)ImageBase; - auto *Table = TableRange.Start.toPtr<PRUNTIME_FUNCTION>(); - if (TableRange.size() == 0 || !Table) - return llvm::Error::success(); - RtlDeleteFunctionTable(Table); - return llvm::Error::success(); -} - -extern "C" llvm::orc::shared::CWrapperFunctionBuffer -cps_register_seh_table_alloc_action(const char *ArgData, size_t ArgSize) { - using namespace llvm::orc::shared; - return WrapperFunction<SPSError(SPSExecutorAddrRange, SPSExecutorAddr)>::handle( - ArgData, ArgSize, registerSEHTable) - .release(); -} - -extern "C" llvm::orc::shared::CWrapperFunctionBuffer -cps_deregister_seh_table_alloc_action(const char *ArgData, size_t ArgSize) { - using namespace llvm::orc::shared; - return WrapperFunction<SPSError(SPSExecutorAddrRange, SPSExecutorAddr)>::handle( - ArgData, ArgSize, deregisterSEHTable) - .release(); -} - -class MinGWSEHRegistrationPlugin final - : public llvm::orc::LinkGraphLinkingLayer::Plugin { -public: - void modifyPassConfig(llvm::orc::MaterializationResponsibility &MR, - llvm::jitlink::LinkGraph &G, - llvm::jitlink::PassConfiguration &Config) override { - using namespace llvm; - using namespace llvm::orc; - using namespace llvm::jitlink; - const Triple &TT = G.getTargetTriple(); - if (!TT.isOSBinFormatCOFF() || TT.getArch() != Triple::x86_64) - return; - - // SEH table liveness relies on the COFF backend's default - // SEHFrameKeepAlivePass(".pdata"), which keeps .pdata alive from its - // referenced function/unwind blocks. Normalized .pdata$/.xdata$ - // sections are kept alive by their associative COMDAT code edges. - // COFF unwind tables address the personality by 32-bit RVA, so it - // must live near JIT code. Retarget .xdata personality references - // to this graph's anonymous pointer jump stubs; the stub pointer - // itself uses a 64-bit relocation to reach the far host runtime. - // External direct calls/jumps from user objects also need nearby - // stubs: their PCRel32 displacement cannot reach a distant CRT DLL. - // The same target reuses the same stub, including personality uses. - Config.PostPrunePasses.push_back(addCOFFJumpStubs); - - // Tables sharing an image base have overlapping lookup ranges in the - // Windows unwinder. Reserve one table for all retained .pdata sections - // in this graph, then fill and sort its entries after relocations. - Config.PostPrunePasses.push_back([](LinkGraph &G) -> Error { - size_t Size = 0; - for (auto &Sec : G.sections()) { - if (!isCOFFUnwindSection(Sec.getName(), ".pdata")) - continue; - for (auto *B : Sec.blocks()) { - if (B->isZeroFill() || B->getSize() % sizeof(RUNTIME_FUNCTION)) - return make_error<JITLinkError>( - "invalid embedded SEH function table"); - Size += B->getSize(); - } - } - if (Size) { - auto &Sec = G.createSection(COFFSEHTableSection, MemProt::Read); - G.createMutableContentBlock(Sec, Size, ExecutorAddr(), - alignof(RUNTIME_FUNCTION), 0); - } - return Error::success(); - }); - - // COFF unwind tables use 32-bit image-relative addresses, so the - // image base must sit at or below the lowest JIT address. Alias the - // external __ImageBase to the lowest defined block once addresses - // are final; a trailing zero block would push RVAs negative. - Config.PostAllocationPasses.push_back([](LinkGraph &G) -> Error { - // A graph-local alias never collides at materialization time, - // no matter how many graphs define the same base name. - if (G.findDefinedSymbolByName(G.intern("__ImageBase"))) - return Error::success(); - auto *ImageBaseExt = - G.findExternalSymbolByName(G.intern("__ImageBase")); - if (!ImageBaseExt) - return Error::success(); - jitlink::Block *Low = nullptr; - for (auto &Sec : G.sections()) { - for (auto *B : Sec.blocks()) { - if (!Low || B->getAddress() < Low->getAddress()) - Low = B; - } - } - if (!Low) - return make_error<JITLinkError>( - "missing embedded __ImageBase content"); - G.makeDefined(*ImageBaseExt, *Low, 0, 8, Linkage::Strong, - Scope::Local, true); - return Error::success(); - }); - - // Copy fixed-up entries into one sorted, allocation-owned table. - // Register it once per graph, with deregistration on link failure or - // teardown before the table and its code are released. - Config.PostFixupPasses.push_back( - [](LinkGraph &G) -> Error { - using namespace llvm::orc::shared; - auto *TableSec = G.findSectionByName(COFFSEHTableSection); - if (!TableSec) - return Error::success(); - auto *Table = *TableSec->blocks().begin(); - std::vector<RUNTIME_FUNCTION> Entries; - Entries.reserve(Table->getSize() / sizeof(RUNTIME_FUNCTION)); - for (auto &Sec : G.sections()) { - if (!isCOFFUnwindSection(Sec.getName(), ".pdata")) - continue; - for (auto *B : Sec.blocks()) { - size_t Start = Entries.size(); - Entries.resize(Start + B->getSize() / sizeof(RUNTIME_FUNCTION)); - if (B->getSize()) - std::memcpy(Entries.data() + Start, B->getContent().data(), - B->getSize()); - } - } - std::sort(Entries.begin(), Entries.end(), - [](const RUNTIME_FUNCTION &L, const RUNTIME_FUNCTION &R) { - return L.BeginAddress < R.BeginAddress; - }); - std::memcpy(Table->getAlreadyMutableContent().data(), Entries.data(), - Table->getSize()); - ExecutorAddrRange TableRange(Table->getAddress(), Table->getSize()); - auto *ImageBaseSym = - G.findDefinedSymbolByName(G.intern("__ImageBase")); - if (!ImageBaseSym) - return make_error<JITLinkError>( - "missing embedded __ImageBase for SEH registration"); - ExecutorAddr ImageBase = ImageBaseSym->getAddress(); - if (ImageBase.isNull()) - return make_error<JITLinkError>("invalid embedded SEH image base"); - auto RegisterAction = - WrapperFunctionCall::Create<SPSArgList<SPSExecutorAddrRange, - SPSExecutorAddr>>( - ExecutorAddr::fromPtr(&cps_register_seh_table_alloc_action), - TableRange, ImageBase); - if (!RegisterAction) - return RegisterAction.takeError(); - auto DeregisterAction = - WrapperFunctionCall::Create<SPSArgList<SPSExecutorAddrRange, - SPSExecutorAddr>>( - ExecutorAddr::fromPtr(&cps_deregister_seh_table_alloc_action), - TableRange, ImageBase); - if (!DeregisterAction) - return DeregisterAction.takeError(); - G.allocActions().push_back( - {std::move(*RegisterAction), std::move(*DeregisterAction)}); - return Error::success(); - }); - (void)MR; - } - - llvm::Error notifyFailed(llvm::orc::MaterializationResponsibility &) override { - return llvm::Error::success(); - } - - llvm::Error notifyRemovingResources(llvm::orc::JITDylib &, - llvm::orc::ResourceKey) override { - return llvm::Error::success(); - } - - void notifyTransferringResources(llvm::orc::JITDylib &, - llvm::orc::ResourceKey, - llvm::orc::ResourceKey) override {} -}; - -// Both user objects and lazily extracted runtime archive members pass through -// this layer, before JITLink builds their graphs or runs plugin passes. -class MinGWObjectLinkingLayer final : public llvm::orc::ObjectLinkingLayer { -public: - using ObjectLinkingLayer::ObjectLinkingLayer; - - void emit(std::unique_ptr<llvm::orc::MaterializationResponsibility> R, - std::unique_ptr<llvm::MemoryBuffer> O) override { - auto Normalized = normalizeMinGWObject(std::move(O)); - if (!Normalized) { - getExecutionSession().reportError(Normalized.takeError()); - R->failMaterialization(); - return; - } - ObjectLinkingLayer::emit(std::move(R), std::move(*Normalized)); - } -}; -#endif - // Embedded JITLink object layer. Created before LLJIT takes ownership so // runEmbedded keeps only the execution flow. COFF flags stay conditional on // the object format; other formats use LLVM defaults. @@ -341,21 +30,15 @@ static std::unique_ptr<llvm::orc::ObjectLinkingLayer> createEmbeddedObjectLayer(llvm::orc::ExecutionSession &ES, llvm::jitlink::JITLinkMemoryManager &MM, const llvm::Triple &TT) { - std::unique_ptr<llvm::orc::ObjectLinkingLayer> Layer; #if defined(_WIN32) && defined(__x86_64__) if (TT.isOSBinFormatCOFF() && TT.getArch() == llvm::Triple::x86_64) - Layer = std::make_unique<MinGWObjectLinkingLayer>(ES, MM); - else + return createMinGWObjectLinkingLayer(ES, MM); #endif - Layer = std::make_unique<llvm::orc::ObjectLinkingLayer>(ES, MM); + auto Layer = std::make_unique<llvm::orc::ObjectLinkingLayer>(ES, MM); if (TT.isOSBinFormatCOFF()) { Layer->setOverrideObjectFlagsWithResponsibilityFlags(true); Layer->setAutoClaimResponsibilityForObjectSymbols(true); } -#if defined(_WIN32) && defined(__x86_64__) - if (TT.isOSBinFormatCOFF() && TT.getArch() == llvm::Triple::x86_64) - Layer->addPlugin(std::make_shared<MinGWSEHRegistrationPlugin>()); -#endif return Layer; } @@ -459,8 +142,6 @@ static llvm::Error defineRuntimeSymbols(llvm::orc::LLJIT &J) { // msvcrt DLL only exports __iob_func, so bind the host's shim directly. Symbols[Intern("__acrt_iob_func")] = ExecutorSymbolDef::fromPtr(&__acrt_iob_func); -#endif -#ifdef _WIN32 // The JIT-generated main references __main on MinGW; provide a no-op so // the host CRT is not initialized a second time. Symbols[Intern("__main")] = @@ -481,15 +162,7 @@ static llvm::Error loadCxxRuntime(llvm::orc::LLJIT &J) { for (auto &Archive : Archives) { llvm::orc::StaticLibraryDefinitionGenerator::GetObjectFileInterface GetInterface; #if defined(_WIN32) && defined(__x86_64__) - // Match the normalized object that MinGWObjectLinkingLayer::emit links. - GetInterface = [](llvm::orc::ExecutionSession &ES, llvm::MemoryBufferRef Ref) - -> llvm::Expected<llvm::orc::MaterializationUnit::Interface> { - auto Normalized = normalizeMinGWObject( - llvm::MemoryBuffer::getMemBuffer(Ref, false)); - if (!Normalized) - return Normalized.takeError(); - return llvm::orc::getObjectFileInterface(ES, (*Normalized)->getMemBufferRef()); - }; + GetInterface = getMinGWObjectFileInterface; #endif auto Generator = llvm::orc::StaticLibraryDefinitionGenerator::Create( J.getObjLinkingLayer(), std::move(Archive), diff --git a/tools/driver/MinGWCOFF.h b/tools/driver/MinGWCOFF.h deleted file mode 100644 index 555dcc8..0000000 --- a/tools/driver/MinGWCOFF.h +++ /dev/null @@ -1,138 +0,0 @@ -#ifndef CPSC_DRIVER_MINGWCOFF_H -#define CPSC_DRIVER_MINGWCOFF_H - -#include "llvm/ADT/DenseSet.h" -#include "llvm/ADT/SmallVector.h" -#include "llvm/ADT/StringMap.h" -#include "llvm/Object/COFF.h" -#include "llvm/Support/MemoryBuffer.h" -#include <cstddef> -#include <cstring> - -namespace { - -inline bool isCOFFUnwindSection(llvm::StringRef Name, llvm::StringRef Base) { - return Name == Base || (Name.starts_with(Base) && - Name.drop_front(Base.size()).starts_with("$")); -} - -// MinGW emits .xdata$foo/.pdata$foo as SELECT_ANY without an external -// COMDAT symbol. JITLink waits for that symbol and never creates the section -// symbol used by relocations. Express their implicit association with .text$foo -// as ordinary associative COMDATs in a private copy of the object instead. -inline llvm::Expected<std::unique_ptr<llvm::MemoryBuffer>> -normalizeMinGWObject(std::unique_ptr<llvm::MemoryBuffer> Buffer) { - using namespace llvm; - auto Object = object::ObjectFile::createObjectFile(Buffer->getMemBufferRef()); - if (!Object) - return Object.takeError(); - auto *COFF = dyn_cast<object::COFFObjectFile>(Object->get()); - if (!COFF || COFF->getMachine() != COFF::IMAGE_FILE_MACHINE_AMD64) - return std::move(Buffer); - - StringMap<int32_t> CodeSections; - DenseSet<int32_t> ExternalSections; - for (const auto &Section : COFF->sections()) { - auto Name = Section.getName(); - if (!Name) - return Name.takeError(); - if (Name->starts_with(".text$") && - (COFF->getCOFFSection(Section)->Characteristics & - COFF::IMAGE_SCN_LNK_COMDAT)) - CodeSections[*Name] = COFF->getSectionID(Section); - } - for (const auto &Symbol : COFF->symbols()) { - auto Sym = COFF->getCOFFSymbol(Symbol); - if (Sym.isExternal() && Sym.getSectionNumber() > 0) - ExternalSections.insert(Sym.getSectionNumber()); - } - - struct Association { size_t Offset; int32_t Parent; }; - SmallVector<Association, 16> Associations; - SmallVector<size_t, 2> PureVirtualReferences; - SmallVector<size_t, 2> PureVirtualFallbacks; - for (const auto &Symbol : COFF->symbols()) { - auto Sym = COFF->getCOFFSymbol(Symbol); - if (auto *Weak = Sym.getWeakExternal()) { - auto Name = Symbol.getName(); - if (!Name) - return Name.takeError(); - if (*Name == "__cxa_pure_virtual" && - Weak->Characteristics == COFF::IMAGE_WEAK_EXTERN_SEARCH_NOLIBRARY) { - auto Fallback = COFF->getSymbol(Weak->TagIndex); - if (!Fallback) - return Fallback.takeError(); - if (Fallback->isAbsolute() && Fallback->getValue() == 0) { - size_t Offset = reinterpret_cast<const char *>(Sym.getRawPtr()) - - Buffer->getBufferStart(); - Offset += Sym.isBigObj() - ? offsetof(object::coff_symbol32, StorageClass) - : offsetof(object::coff_symbol16, StorageClass); - PureVirtualReferences.push_back(Offset); - size_t FallbackOffset = - reinterpret_cast<const char *>(Fallback->getRawPtr()) - - Buffer->getBufferStart(); - FallbackOffset += Fallback->isBigObj() - ? offsetof(object::coff_symbol32, StorageClass) - : offsetof(object::coff_symbol16, StorageClass); - PureVirtualFallbacks.push_back(FallbackOffset); - } - } - } - auto *Def = Sym.getSectionDefinition(); - if (!Def || Def->Selection != COFF::IMAGE_COMDAT_SELECT_ANY || - Sym.getSectionNumber() <= 0 || - ExternalSections.contains(Sym.getSectionNumber())) - continue; - auto Section = COFF->getSection(Sym.getSectionNumber()); - if (!Section) - return Section.takeError(); - if (!((*Section)->Characteristics & COFF::IMAGE_SCN_LNK_COMDAT)) - continue; - auto Name = COFF->getSectionName(*Section); - if (!Name) - return Name.takeError(); - if (!Name->starts_with(".xdata$") && !Name->starts_with(".pdata$")) - continue; - std::string CodeName = (".text$" + Name->drop_front(7)).str(); - auto Parent = CodeSections.find(CodeName); - if (Parent == CodeSections.end()) - return make_error<StringError>( - "missing MinGW unwind code section '" + CodeName + "' in '" + - Buffer->getBufferIdentifier().str() + "'", - inconvertibleErrorCode()); - Associations.push_back({static_cast<size_t>( - reinterpret_cast<const char *>(Def) - - Buffer->getBufferStart()), - Parent->second}); - } - if (Associations.empty() && PureVirtualReferences.empty()) - return std::move(Buffer); - - auto Copy = WritableMemoryBuffer::getNewUninitMemBuffer( - Buffer->getBufferSize(), Buffer->getBufferIdentifier()); - std::memcpy(Copy->getBufferStart(), Buffer->getBufferStart(), - Buffer->getBufferSize()); - for (const auto &A : Associations) { - auto *Def = reinterpret_cast<object::coff_aux_section_definition *>( - Copy->getBufferStart() + A.Offset); - Def->Selection = COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE; - Def->NumberLowPart = A.Parent & 0xffff; - Def->NumberHighPart = static_cast<uint32_t>(A.Parent) >> 16; - } - // JITLink cannot alias a weak external to an absolute-zero fallback. - // The runner always supplies the host's __cxa_pure_virtual, so this known - // optional ABI reference can be an ordinary external. Keep its auxiliary - // entry count intact so the remaining symbol indices do not move. - for (size_t Offset : PureVirtualReferences) - Copy->getBufferStart()[Offset] = COFF::IMAGE_SYM_CLASS_EXTERNAL; - // Only the now-unused weak auxiliary record references the fallback. - // Keep it local so archive interfaces do not advertise a global definition. - for (size_t Offset : PureVirtualFallbacks) - Copy->getBufferStart()[Offset] = COFF::IMAGE_SYM_CLASS_STATIC; - return std::unique_ptr<MemoryBuffer>(std::move(Copy)); -} - -} // namespace - -#endif diff --git a/tools/driver/MinGWJIT.cc b/tools/driver/MinGWJIT.cc new file mode 100644 index 0000000..7886b80 --- /dev/null +++ b/tools/driver/MinGWJIT.cc @@ -0,0 +1,447 @@ +#include "MinGWJIT.h" + +#if defined(_WIN32) && defined(__x86_64__) +#ifndef NOMINMAX +#define NOMINMAX +#endif +#include "llvm/ADT/DenseSet.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/StringMap.h" +#include "llvm/ExecutionEngine/JITLink/JITLink.h" +#include "llvm/ExecutionEngine/JITLink/x86_64.h" +#include "llvm/ExecutionEngine/Orc/ObjectFileInterface.h" +#include "llvm/ExecutionEngine/Orc/ObjectLinkingLayer.h" +#include "llvm/ExecutionEngine/Orc/Shared/WrapperFunctionUtils.h" +#include "llvm/Object/COFF.h" +#include "llvm/Support/Endian.h" +#include "llvm/Support/MemoryBuffer.h" +#include <algorithm> +#include <cstddef> +#include <cstring> +#include <limits> +#include <vector> + +namespace { + +bool isCOFFUnwindSection(llvm::StringRef Name, llvm::StringRef Base) { + return Name == Base || (Name.starts_with(Base) && + Name.drop_front(Base.size()).starts_with("$")); +} + +// MinGW emits .xdata$foo/.pdata$foo as SELECT_ANY without an external +// COMDAT symbol. JITLink waits for that symbol and never creates the section +// symbol used by relocations. Express their implicit association with .text$foo +// as ordinary associative COMDATs in a private copy of the object instead. +llvm::Expected<std::unique_ptr<llvm::MemoryBuffer>> +normalizeMinGWObject(std::unique_ptr<llvm::MemoryBuffer> Buffer) { + using namespace llvm; + auto Object = object::ObjectFile::createObjectFile(Buffer->getMemBufferRef()); + if (!Object) + return Object.takeError(); + auto *COFF = dyn_cast<object::COFFObjectFile>(Object->get()); + if (!COFF || COFF->getMachine() != COFF::IMAGE_FILE_MACHINE_AMD64) + return std::move(Buffer); + + StringMap<int32_t> CodeSections; + DenseSet<int32_t> ExternalSections; + for (const auto &Section : COFF->sections()) { + auto Name = Section.getName(); + if (!Name) + return Name.takeError(); + if (Name->starts_with(".text$") && + (COFF->getCOFFSection(Section)->Characteristics & + COFF::IMAGE_SCN_LNK_COMDAT)) + CodeSections[*Name] = COFF->getSectionID(Section); + } + for (const auto &Symbol : COFF->symbols()) { + auto Sym = COFF->getCOFFSymbol(Symbol); + if (Sym.isExternal() && Sym.getSectionNumber() > 0) + ExternalSections.insert(Sym.getSectionNumber()); + } + + struct Association { size_t Offset; int32_t Parent; }; + SmallVector<Association, 16> Associations; + SmallVector<size_t, 2> PureVirtualReferences; + SmallVector<size_t, 2> PureVirtualFallbacks; + for (const auto &Symbol : COFF->symbols()) { + auto Sym = COFF->getCOFFSymbol(Symbol); + if (auto *Weak = Sym.getWeakExternal()) { + auto Name = Symbol.getName(); + if (!Name) + return Name.takeError(); + if (*Name == "__cxa_pure_virtual" && + Weak->Characteristics == COFF::IMAGE_WEAK_EXTERN_SEARCH_NOLIBRARY) { + auto Fallback = COFF->getSymbol(Weak->TagIndex); + if (!Fallback) + return Fallback.takeError(); + if (Fallback->isAbsolute() && Fallback->getValue() == 0) { + size_t Offset = reinterpret_cast<const char *>(Sym.getRawPtr()) - + Buffer->getBufferStart(); + Offset += Sym.isBigObj() + ? offsetof(object::coff_symbol32, StorageClass) + : offsetof(object::coff_symbol16, StorageClass); + PureVirtualReferences.push_back(Offset); + size_t FallbackOffset = + reinterpret_cast<const char *>(Fallback->getRawPtr()) - + Buffer->getBufferStart(); + FallbackOffset += Fallback->isBigObj() + ? offsetof(object::coff_symbol32, StorageClass) + : offsetof(object::coff_symbol16, StorageClass); + PureVirtualFallbacks.push_back(FallbackOffset); + } + } + } + auto *Def = Sym.getSectionDefinition(); + if (!Def || Def->Selection != COFF::IMAGE_COMDAT_SELECT_ANY || + Sym.getSectionNumber() <= 0 || + ExternalSections.contains(Sym.getSectionNumber())) + continue; + auto Section = COFF->getSection(Sym.getSectionNumber()); + if (!Section) + return Section.takeError(); + if (!((*Section)->Characteristics & COFF::IMAGE_SCN_LNK_COMDAT)) + continue; + auto Name = COFF->getSectionName(*Section); + if (!Name) + return Name.takeError(); + if (!Name->starts_with(".xdata$") && !Name->starts_with(".pdata$")) + continue; + std::string CodeName = (".text$" + Name->drop_front(7)).str(); + auto Parent = CodeSections.find(CodeName); + if (Parent == CodeSections.end()) + return make_error<StringError>( + "missing MinGW unwind code section '" + CodeName + "' in '" + + Buffer->getBufferIdentifier().str() + "'", + inconvertibleErrorCode()); + Associations.push_back({static_cast<size_t>( + reinterpret_cast<const char *>(Def) - + Buffer->getBufferStart()), + Parent->second}); + } + if (Associations.empty() && PureVirtualReferences.empty()) + return std::move(Buffer); + + auto Copy = WritableMemoryBuffer::getNewUninitMemBuffer( + Buffer->getBufferSize(), Buffer->getBufferIdentifier()); + std::memcpy(Copy->getBufferStart(), Buffer->getBufferStart(), + Buffer->getBufferSize()); + for (const auto &A : Associations) { + auto *Def = reinterpret_cast<object::coff_aux_section_definition *>( + Copy->getBufferStart() + A.Offset); + Def->Selection = COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE; + Def->NumberLowPart = A.Parent & 0xffff; + Def->NumberHighPart = static_cast<uint32_t>(A.Parent) >> 16; + } + // JITLink cannot alias a weak external to an absolute-zero fallback. + // The runner always supplies the host's __cxa_pure_virtual, so this known + // optional ABI reference can be an ordinary external. Keep its auxiliary + // entry count intact so the remaining symbol indices do not move. + for (size_t Offset : PureVirtualReferences) + Copy->getBufferStart()[Offset] = COFF::IMAGE_SYM_CLASS_EXTERNAL; + // Only the now-unused weak auxiliary record references the fallback. + // Keep it local so archive interfaces do not advertise a global definition. + for (size_t Offset : PureVirtualFallbacks) + Copy->getBufferStart()[Offset] = COFF::IMAGE_SYM_CLASS_STATIC; + return std::unique_ptr<MemoryBuffer>(std::move(Copy)); +} + +} // namespace + +// Parse LLVM COFF helpers and normalization before Windows IMAGE_* macros. +#include <windows.h> + +namespace { + +// Keep MinGW's GNU C++ ABI while registering COFF unwind tables with Windows. +// Full ORC COFFPlatform setup loads the VC runtime, which this build does not use. +static constexpr llvm::StringLiteral COFFSEHTableSection = "$__cpsc_seh"; + +static llvm::Error addCOFFJumpStubs(llvm::jitlink::LinkGraph &G) { + using namespace llvm; + using namespace llvm::jitlink; + using namespace llvm::jitlink::x86_64; + GOTTableManager GOT(G); + PLTTableManager PLT(G, GOT); + // Creating a stub may add sections/blocks. Visit only the original blocks. + std::vector<Block *> Blocks(G.blocks().begin(), G.blocks().end()); + for (auto *B : Blocks) { + bool Executable = (B->getSection().getMemProt() & orc::MemProt::Exec) != + orc::MemProt::None; + for (auto &E : B->edges()) { + Symbol &Target = E.getTarget(); + if (!Target.isExternal()) + continue; + bool Personality = false; + if (isCOFFUnwindSection(B->getSection().getName(), ".xdata") && + Target.hasName()) { + StringRef Name = *Target.getName(); + Personality = Name == "__gxx_personality_seh0" || + Name == "__gxx_personality_sj0" || + Name == "__gxx_personality_v0"; + } + // COFF's private PCRel32 kind is lowered only in PreFixup. + // Use its name rather than confusing it with x86_64::PCRel32. + // Only E8/E9 direct branches with a plain symbol target need a + // jump stub; RIP-relative data and indirect calls must stay intact. + bool DirectBranch = false; + if (Executable && !B->isZeroFill() && E.getAddend() == 0 && + StringRef(G.getEdgeKindName(E.getKind())) == "PCRel32") { + auto Content = B->getContent(); + size_t Offset = E.getOffset(); + if (Offset > 0 && Offset <= Content.size() && + Content.size() - Offset >= 4) { + unsigned char Opcode = Content[Offset - 1]; + DirectBranch = Opcode == 0xe8 || Opcode == 0xe9; + } + } + if (Personality || DirectBranch) + E.setTarget(PLT.getEntryForTarget(G, Target)); + } + } + return Error::success(); +} + +static llvm::Error registerSEHTable(llvm::orc::ExecutorAddrRange TableRange, + llvm::orc::ExecutorAddr ImageBase) { + using llvm::make_error; + using llvm::StringError; + using llvm::inconvertibleErrorCode; + size_t Size = TableRange.size(); + if (Size == 0 || ImageBase.isNull() || Size % sizeof(RUNTIME_FUNCTION)) + return make_error<StringError>("invalid embedded SEH function table", + inconvertibleErrorCode()); + uint64_t Count64 = Size / sizeof(RUNTIME_FUNCTION); + if (Count64 > static_cast<uint64_t>(std::numeric_limits<DWORD>::max())) + return make_error<StringError>("invalid embedded SEH function table", + inconvertibleErrorCode()); + auto *Table = TableRange.Start.toPtr<const RUNTIME_FUNCTION *>(); + DWORD PrevBegin = 0; + for (uint64_t I = 0; I < Count64; ++I) { + DWORD Begin = llvm::support::endian::read32le( + reinterpret_cast<const char *>(Table + I) + 0); + DWORD End = llvm::support::endian::read32le( + reinterpret_cast<const char *>(Table + I) + 4); + if (!(Begin < End)) + return make_error<StringError>("invalid embedded SEH function table", + inconvertibleErrorCode()); + if (I > 0 && !(PrevBegin < Begin)) + return make_error<StringError>("invalid embedded SEH function table", + inconvertibleErrorCode()); + PrevBegin = Begin; + } + auto *MutableTable = const_cast<PRUNTIME_FUNCTION>(Table); + DWORD Count = static_cast<DWORD>(Count64); + DWORD64 Base = static_cast<DWORD64>(ImageBase.getValue()); + if (!RtlAddFunctionTable(MutableTable, Count, Base)) + return make_error<StringError>("cannot register embedded SEH function table", + inconvertibleErrorCode()); + return llvm::Error::success(); +} + +static llvm::Error deregisterSEHTable(llvm::orc::ExecutorAddrRange TableRange, + llvm::orc::ExecutorAddr) { + auto *Table = TableRange.Start.toPtr<PRUNTIME_FUNCTION>(); + if (TableRange.size() == 0 || !Table) + return llvm::Error::success(); + RtlDeleteFunctionTable(Table); + return llvm::Error::success(); +} + +extern "C" llvm::orc::shared::CWrapperFunctionBuffer +cps_register_seh_table_alloc_action(const char *ArgData, size_t ArgSize) { + using namespace llvm::orc::shared; + return WrapperFunction<SPSError(SPSExecutorAddrRange, SPSExecutorAddr)>::handle( + ArgData, ArgSize, registerSEHTable) + .release(); +} + +extern "C" llvm::orc::shared::CWrapperFunctionBuffer +cps_deregister_seh_table_alloc_action(const char *ArgData, size_t ArgSize) { + using namespace llvm::orc::shared; + return WrapperFunction<SPSError(SPSExecutorAddrRange, SPSExecutorAddr)>::handle( + ArgData, ArgSize, deregisterSEHTable) + .release(); +} + +class MinGWSEHRegistrationPlugin final + : public llvm::orc::LinkGraphLinkingLayer::Plugin { +public: + void modifyPassConfig(llvm::orc::MaterializationResponsibility &, + llvm::jitlink::LinkGraph &G, + llvm::jitlink::PassConfiguration &Config) override { + using namespace llvm; + using namespace llvm::orc; + using namespace llvm::jitlink; + const Triple &TT = G.getTargetTriple(); + if (!TT.isOSBinFormatCOFF() || TT.getArch() != Triple::x86_64) + return; + + // LLVM's SEHFrameKeepAlivePass retains .pdata; associative COMDATs + // retain the normalized suffixed sections. Nearby jump stubs let + // 32-bit personality RVAs and direct branches reach the host runtime. + Config.PostPrunePasses.push_back(addCOFFJumpStubs); + + // Tables sharing an image base have overlapping lookup ranges in the + // Windows unwinder. Reserve one table for all retained .pdata sections + // in this graph, then fill and sort its entries after relocations. + Config.PostPrunePasses.push_back([](LinkGraph &G) -> Error { + size_t Size = 0; + for (auto &Sec : G.sections()) { + if (!isCOFFUnwindSection(Sec.getName(), ".pdata")) + continue; + for (auto *B : Sec.blocks()) { + if (B->isZeroFill() || B->getSize() % sizeof(RUNTIME_FUNCTION)) + return make_error<JITLinkError>( + "invalid embedded SEH function table"); + Size += B->getSize(); + } + } + if (Size) { + auto &Sec = G.createSection(COFFSEHTableSection, MemProt::Read); + G.createMutableContentBlock(Sec, Size, ExecutorAddr(), + alignof(RUNTIME_FUNCTION), 0); + } + return Error::success(); + }); + + // COFF unwind tables use 32-bit image-relative addresses, so the + // image base must sit at or below the lowest JIT address. Alias the + // external __ImageBase to the lowest defined block once addresses + // are final; a trailing zero block would push RVAs negative. + Config.PostAllocationPasses.push_back([](LinkGraph &G) -> Error { + // A graph-local alias never collides at materialization time, + // no matter how many graphs define the same base name. + if (G.findDefinedSymbolByName(G.intern("__ImageBase"))) + return Error::success(); + auto *ImageBaseExt = + G.findExternalSymbolByName(G.intern("__ImageBase")); + if (!ImageBaseExt) + return Error::success(); + jitlink::Block *Low = nullptr; + for (auto &Sec : G.sections()) { + for (auto *B : Sec.blocks()) { + if (!Low || B->getAddress() < Low->getAddress()) + Low = B; + } + } + if (!Low) + return make_error<JITLinkError>( + "missing embedded __ImageBase content"); + G.makeDefined(*ImageBaseExt, *Low, 0, 8, Linkage::Strong, + Scope::Local, true); + return Error::success(); + }); + + // Copy fixed-up entries into one sorted, allocation-owned table. + // Register it once per graph, with deregistration on link failure or + // teardown before the table and its code are released. + Config.PostFixupPasses.push_back( + [](LinkGraph &G) -> Error { + using namespace llvm::orc::shared; + auto *TableSec = G.findSectionByName(COFFSEHTableSection); + if (!TableSec) + return Error::success(); + auto *Table = *TableSec->blocks().begin(); + std::vector<RUNTIME_FUNCTION> Entries; + Entries.reserve(Table->getSize() / sizeof(RUNTIME_FUNCTION)); + for (auto &Sec : G.sections()) { + if (!isCOFFUnwindSection(Sec.getName(), ".pdata")) + continue; + for (auto *B : Sec.blocks()) { + size_t Start = Entries.size(); + Entries.resize(Start + B->getSize() / sizeof(RUNTIME_FUNCTION)); + if (B->getSize()) + std::memcpy(Entries.data() + Start, B->getContent().data(), + B->getSize()); + } + } + std::sort(Entries.begin(), Entries.end(), + [](const RUNTIME_FUNCTION &L, const RUNTIME_FUNCTION &R) { + return L.BeginAddress < R.BeginAddress; + }); + std::memcpy(Table->getAlreadyMutableContent().data(), Entries.data(), + Table->getSize()); + ExecutorAddrRange TableRange(Table->getAddress(), Table->getSize()); + auto *ImageBaseSym = + G.findDefinedSymbolByName(G.intern("__ImageBase")); + if (!ImageBaseSym) + return make_error<JITLinkError>( + "missing embedded __ImageBase for SEH registration"); + ExecutorAddr ImageBase = ImageBaseSym->getAddress(); + if (ImageBase.isNull()) + return make_error<JITLinkError>("invalid embedded SEH image base"); + auto RegisterAction = + WrapperFunctionCall::Create<SPSArgList<SPSExecutorAddrRange, + SPSExecutorAddr>>( + ExecutorAddr::fromPtr(&cps_register_seh_table_alloc_action), + TableRange, ImageBase); + if (!RegisterAction) + return RegisterAction.takeError(); + auto DeregisterAction = + WrapperFunctionCall::Create<SPSArgList<SPSExecutorAddrRange, + SPSExecutorAddr>>( + ExecutorAddr::fromPtr(&cps_deregister_seh_table_alloc_action), + TableRange, ImageBase); + if (!DeregisterAction) + return DeregisterAction.takeError(); + G.allocActions().push_back( + {std::move(*RegisterAction), std::move(*DeregisterAction)}); + return Error::success(); + }); + } + + llvm::Error notifyFailed(llvm::orc::MaterializationResponsibility &) override { + return llvm::Error::success(); + } + + llvm::Error notifyRemovingResources(llvm::orc::JITDylib &, + llvm::orc::ResourceKey) override { + return llvm::Error::success(); + } + + void notifyTransferringResources(llvm::orc::JITDylib &, + llvm::orc::ResourceKey, + llvm::orc::ResourceKey) override {} +}; + +// Both user objects and lazily extracted runtime archive members pass through +// this layer, before JITLink builds their graphs or runs plugin passes. +class MinGWObjectLinkingLayer final : public llvm::orc::ObjectLinkingLayer { +public: + using ObjectLinkingLayer::ObjectLinkingLayer; + + void emit(std::unique_ptr<llvm::orc::MaterializationResponsibility> R, + std::unique_ptr<llvm::MemoryBuffer> O) override { + auto Normalized = normalizeMinGWObject(std::move(O)); + if (!Normalized) { + getExecutionSession().reportError(Normalized.takeError()); + R->failMaterialization(); + return; + } + ObjectLinkingLayer::emit(std::move(R), std::move(*Normalized)); + } +}; + +} // namespace + +std::unique_ptr<llvm::orc::ObjectLinkingLayer> +createMinGWObjectLinkingLayer(llvm::orc::ExecutionSession &ES, + llvm::jitlink::JITLinkMemoryManager &MM) { + auto Layer = std::make_unique<MinGWObjectLinkingLayer>(ES, MM); + Layer->setOverrideObjectFlagsWithResponsibilityFlags(true); + Layer->setAutoClaimResponsibilityForObjectSymbols(true); + Layer->addPlugin(std::make_shared<MinGWSEHRegistrationPlugin>()); + return Layer; +} + +llvm::Expected<llvm::orc::MaterializationUnit::Interface> +getMinGWObjectFileInterface(llvm::orc::ExecutionSession &ES, + llvm::MemoryBufferRef Ref) { + // Archive interfaces must describe the same normalized object emit links. + auto Normalized = normalizeMinGWObject( + llvm::MemoryBuffer::getMemBuffer(Ref, false)); + if (!Normalized) + return Normalized.takeError(); + return llvm::orc::getObjectFileInterface(ES, (*Normalized)->getMemBufferRef()); +} +#endif diff --git a/tools/driver/MinGWJIT.h b/tools/driver/MinGWJIT.h new file mode 100644 index 0000000..8064f0f --- /dev/null +++ b/tools/driver/MinGWJIT.h @@ -0,0 +1,25 @@ +#ifndef CPSC_DRIVER_MINGWJIT_H +#define CPSC_DRIVER_MINGWJIT_H + +#if defined(_WIN32) && defined(__x86_64__) +#include "llvm/ExecutionEngine/Orc/Core.h" +#include "llvm/Support/MemoryBufferRef.h" +#include <memory> + +namespace llvm::jitlink { +class JITLinkMemoryManager; +} +namespace llvm::orc { +class ObjectLinkingLayer; +} + +std::unique_ptr<llvm::orc::ObjectLinkingLayer> +createMinGWObjectLinkingLayer(llvm::orc::ExecutionSession &ES, + llvm::jitlink::JITLinkMemoryManager &MM); + +llvm::Expected<llvm::orc::MaterializationUnit::Interface> +getMinGWObjectFileInterface(llvm::orc::ExecutionSession &ES, + llvm::MemoryBufferRef Ref); +#endif + +#endif |
