compute-runtime/shared/source/compiler_interface/linker.cpp

504 lines
24 KiB
C++

/*
* Copyright (C) 2019-2022 Intel Corporation
*
* SPDX-License-Identifier: MIT
*
*/
#include "shared/source/compiler_interface/linker.h"
#include "shared/source/command_stream/command_stream_receiver.h"
#include "shared/source/compiler_interface/linker.inl"
#include "shared/source/device/device.h"
#include "shared/source/device_binary_format/elf/zebin_elf.h"
#include "shared/source/helpers/blit_commands_helper.h"
#include "shared/source/helpers/debug_helpers.h"
#include "shared/source/helpers/hw_helper.h"
#include "shared/source/helpers/ptr_math.h"
#include "shared/source/kernel/implicit_args.h"
#include "shared/source/kernel/kernel_descriptor.h"
#include "shared/source/memory_manager/graphics_allocation.h"
#include "shared/source/memory_manager/memory_manager.h"
#include "RelocationInfo.h"
#include <sstream>
namespace NEO {
SegmentType LinkerInput::getSegmentForSection(ConstStringRef name) {
if (name == NEO::Elf::SectionsNamesZebin::dataConst || name == NEO::Elf::SectionsNamesZebin::dataGlobalConst) {
return NEO::SegmentType::GlobalConstants;
} else if (name == NEO::Elf::SectionsNamesZebin::dataGlobal) {
return NEO::SegmentType::GlobalVariables;
} else if (name == NEO::Elf::SectionsNamesZebin::dataConstString) {
return NEO::SegmentType::GlobalStrings;
} else if (name.startsWith(NEO::Elf::SpecialSectionNames::text.data())) {
return NEO::SegmentType::Instructions;
}
return NEO::SegmentType::Unknown;
}
bool LinkerInput::decodeGlobalVariablesSymbolTable(const void *data, uint32_t numEntries) {
auto symbolEntryIt = reinterpret_cast<const vISA::GenSymEntry *>(data);
auto symbolEntryEnd = symbolEntryIt + numEntries;
symbols.reserve(symbols.size() + numEntries);
for (; symbolEntryIt != symbolEntryEnd; ++symbolEntryIt) {
DEBUG_BREAK_IF(symbols.count(symbolEntryIt->s_name) > 0);
SymbolInfo &symbolInfo = symbols[symbolEntryIt->s_name];
symbolInfo.offset = symbolEntryIt->s_offset;
symbolInfo.size = symbolEntryIt->s_size;
switch (symbolEntryIt->s_type) {
default:
DEBUG_BREAK_IF(true);
this->valid = false;
return false;
case vISA::S_GLOBAL_VAR:
symbolInfo.segment = SegmentType::GlobalVariables;
traits.exportsGlobalVariables = true;
break;
case vISA::S_GLOBAL_VAR_CONST:
symbolInfo.segment = SegmentType::GlobalConstants;
traits.exportsGlobalConstants = true;
break;
}
}
return true;
}
bool LinkerInput::decodeExportedFunctionsSymbolTable(const void *data, uint32_t numEntries, uint32_t instructionsSegmentId) {
auto symbolEntryIt = reinterpret_cast<const vISA::GenSymEntry *>(data);
auto symbolEntryEnd = symbolEntryIt + numEntries;
symbols.reserve(symbols.size() + numEntries);
for (; symbolEntryIt != symbolEntryEnd; ++symbolEntryIt) {
SymbolInfo &symbolInfo = symbols[symbolEntryIt->s_name];
symbolInfo.offset = symbolEntryIt->s_offset;
symbolInfo.size = symbolEntryIt->s_size;
switch (symbolEntryIt->s_type) {
default:
DEBUG_BREAK_IF(true);
this->valid = false;
return false;
case vISA::S_UNDEF:
if (this->undefinedSymbolsAllowed) {
symbols.erase(symbolEntryIt->s_name);
break;
} else {
DEBUG_BREAK_IF(true);
this->valid = false;
return false;
}
case vISA::S_GLOBAL_VAR:
symbolInfo.segment = SegmentType::GlobalVariables;
traits.exportsGlobalVariables = true;
break;
case vISA::S_GLOBAL_VAR_CONST:
symbolInfo.segment = SegmentType::GlobalConstants;
traits.exportsGlobalConstants = true;
break;
case vISA::S_FUNC:
symbolInfo.segment = SegmentType::Instructions;
traits.exportsFunctions = true;
UNRECOVERABLE_IF((this->exportedFunctionsSegmentId != -1) && (this->exportedFunctionsSegmentId != static_cast<int32_t>(instructionsSegmentId)));
this->exportedFunctionsSegmentId = static_cast<int32_t>(instructionsSegmentId);
break;
}
}
return true;
}
bool LinkerInput::decodeRelocationTable(const void *data, uint32_t numEntries, uint32_t instructionsSegmentId) {
this->traits.requiresPatchingOfInstructionSegments = true;
auto relocEntryIt = reinterpret_cast<const vISA::GenRelocEntry *>(data);
auto relocEntryEnd = relocEntryIt + numEntries;
if (instructionsSegmentId >= relocations.size()) {
static_assert(std::is_nothrow_move_constructible<decltype(relocations[0])>::value, "");
relocations.resize(instructionsSegmentId + 1);
}
auto &outRelocInfo = relocations[instructionsSegmentId];
outRelocInfo.reserve(numEntries);
for (; relocEntryIt != relocEntryEnd; ++relocEntryIt) {
RelocationInfo relocInfo{};
relocInfo.offset = relocEntryIt->r_offset;
relocInfo.symbolName = relocEntryIt->r_symbol;
relocInfo.relocationSegment = SegmentType::Instructions;
switch (relocEntryIt->r_type) {
default:
DEBUG_BREAK_IF(true);
this->valid = false;
return false;
case vISA::R_SYM_ADDR:
relocInfo.type = RelocationInfo::Type::Address;
break;
case vISA::R_SYM_ADDR_32:
relocInfo.type = RelocationInfo::Type::AddressLow;
break;
case vISA::R_SYM_ADDR_32_HI:
relocInfo.type = RelocationInfo::Type::AddressHigh;
break;
case vISA::R_PER_THREAD_PAYLOAD_OFFSET_32:
relocInfo.type = RelocationInfo::Type::PerThreadPayloadOffset;
break;
}
outRelocInfo.push_back(std::move(relocInfo));
}
return true;
}
void LinkerInput::addDataRelocationInfo(const RelocationInfo &relocationInfo) {
DEBUG_BREAK_IF((relocationInfo.relocationSegment != SegmentType::GlobalConstants) && (relocationInfo.relocationSegment != SegmentType::GlobalVariables));
this->traits.requiresPatchingOfGlobalVariablesBuffer |= (relocationInfo.relocationSegment == SegmentType::GlobalVariables);
this->traits.requiresPatchingOfGlobalConstantsBuffer |= (relocationInfo.relocationSegment == SegmentType::GlobalConstants);
this->dataRelocations.push_back(relocationInfo);
}
void LinkerInput::addElfTextSegmentRelocation(RelocationInfo relocationInfo, uint32_t instructionsSegmentId) {
this->traits.requiresPatchingOfInstructionSegments = true;
if (instructionsSegmentId >= relocations.size()) {
static_assert(std::is_nothrow_move_constructible<decltype(relocations[0])>::value, "");
relocations.resize(instructionsSegmentId + 1);
}
auto &outRelocInfo = relocations[instructionsSegmentId];
relocationInfo.relocationSegment = SegmentType::Instructions;
outRelocInfo.push_back(std::move(relocationInfo));
}
void LinkerInput::decodeElfSymbolTableAndRelocations(Elf::Elf<Elf::EI_CLASS_64> &elf, const SectionNameToSegmentIdMap &nameToSegmentId) {
for (auto &reloc : elf.getRelocations()) {
NEO::LinkerInput::RelocationInfo relocationInfo;
relocationInfo.offset = reloc.offset;
relocationInfo.symbolName = reloc.symbolName;
switch (reloc.relocType) {
case uint32_t(Elf::RELOCATION_X8664_TYPE::R_X8664_64):
relocationInfo.type = NEO::LinkerInput::RelocationInfo::Type::Address;
break;
case uint32_t(Elf::RELOCATION_X8664_TYPE::R_X8664_32):
relocationInfo.type = NEO::LinkerInput::RelocationInfo::Type::AddressLow;
break;
default: // Zebin relocation type
relocationInfo.type = reloc.relocType < uint32_t(NEO::LinkerInput::RelocationInfo::Type::RelocTypeMax)
? static_cast<NEO::LinkerInput::RelocationInfo::Type>(reloc.relocType)
: NEO::LinkerInput::RelocationInfo::Type::Unknown;
break;
}
auto name = elf.getSectionName(reloc.targetSectionIndex);
ConstStringRef nameRef(name);
if (nameRef.startsWith(NEO::Elf::SectionsNamesZebin::textPrefix.data())) {
auto kernelName = name.substr(static_cast<int>(NEO::Elf::SectionsNamesZebin::textPrefix.length()));
auto segmentIdIter = nameToSegmentId.find(kernelName);
if (segmentIdIter != nameToSegmentId.end()) {
this->addElfTextSegmentRelocation(relocationInfo, segmentIdIter->second);
}
} else if (nameRef.startsWith(NEO::Elf::SpecialSectionNames::data.data())) {
auto symbolSectionName = elf.getSectionName(reloc.symbolSectionIndex);
auto symbolSegment = getSegmentForSection(symbolSectionName);
auto relocationSegment = getSegmentForSection(nameRef);
if (symbolSegment != NEO::SegmentType::Unknown &&
(relocationSegment == NEO::SegmentType::GlobalConstants || relocationSegment == NEO::SegmentType::GlobalVariables)) {
relocationInfo.relocationSegment = relocationSegment;
this->addDataRelocationInfo(relocationInfo);
}
}
}
symbols.reserve(elf.getSymbols().size());
for (auto &symbol : elf.getSymbols()) {
auto bind = elf.extractSymbolBind(symbol);
if (bind == Elf::SYMBOL_TABLE_BIND::STB_GLOBAL) {
SymbolInfo symbolInfo;
symbolInfo.offset = static_cast<uint32_t>(symbol.value);
symbolInfo.size = static_cast<uint32_t>(symbol.size);
auto type = elf.extractSymbolType(symbol);
auto symbolSectionName = elf.getSectionName(symbol.shndx);
auto symbolSegment = getSegmentForSection(symbolSectionName);
switch (type) {
default:
this->valid &= this->undefinedSymbolsAllowed;
DEBUG_BREAK_IF(false == this->undefinedSymbolsAllowed);
continue;
case Elf::SYMBOL_TABLE_TYPE::STT_OBJECT:
symbolInfo.segment = symbolSegment;
traits.exportsGlobalVariables |= symbolSegment == SegmentType::GlobalVariables;
traits.exportsGlobalConstants |= symbolSegment == SegmentType::GlobalConstants;
break;
case Elf::SYMBOL_TABLE_TYPE::STT_FUNC: {
auto kernelName = symbolSectionName.substr(static_cast<int>(NEO::Elf::SectionsNamesZebin::textPrefix.length()));
auto segmentIdIter = nameToSegmentId.find(kernelName);
if (segmentIdIter != nameToSegmentId.end()) {
symbolInfo.segment = SegmentType::Instructions;
traits.exportsFunctions = true;
int32_t instructionsSegmentId = static_cast<int32_t>(segmentIdIter->second);
UNRECOVERABLE_IF((this->exportedFunctionsSegmentId != -1) && (this->exportedFunctionsSegmentId != instructionsSegmentId));
this->exportedFunctionsSegmentId = instructionsSegmentId;
}
} break;
}
symbols.insert({elf.getSymbolName(symbol.name), symbolInfo});
}
}
}
bool Linker::processRelocations(const SegmentInfo &globalVariables, const SegmentInfo &globalConstants, const SegmentInfo &exportedFunctions, const SegmentInfo &globalStrings) {
relocatedSymbols.reserve(data.getSymbols().size());
for (auto &symbol : data.getSymbols()) {
const SegmentInfo *seg = nullptr;
switch (symbol.second.segment) {
default:
DEBUG_BREAK_IF(true);
return false;
case SegmentType::GlobalVariables:
seg = &globalVariables;
break;
case SegmentType::GlobalConstants:
seg = &globalConstants;
break;
case SegmentType::GlobalStrings:
seg = &globalStrings;
break;
case SegmentType::Instructions:
seg = &exportedFunctions;
break;
}
uintptr_t gpuAddress = seg->gpuAddress + symbol.second.offset;
if (symbol.second.offset + symbol.second.size > seg->segmentSize) {
DEBUG_BREAK_IF(true);
return false;
}
relocatedSymbols[symbol.first] = {symbol.second, gpuAddress};
}
return true;
}
uint32_t addressSizeInBytes(LinkerInput::RelocationInfo::Type relocationtype) {
return (relocationtype == LinkerInput::RelocationInfo::Type::Address) ? sizeof(uintptr_t) : sizeof(uint32_t);
}
void Linker::patchAddress(void *relocAddress, const Linker::RelocatedSymbol &symbol, const Linker::RelocationInfo &relocation) {
uint64_t gpuAddressAs64bit = static_cast<uint64_t>(symbol.gpuAddress);
switch (relocation.type) {
default:
UNRECOVERABLE_IF(RelocationInfo::Type::Address != relocation.type);
*reinterpret_cast<uintptr_t *>(relocAddress) = symbol.gpuAddress;
break;
case RelocationInfo::Type::AddressLow:
*reinterpret_cast<uint32_t *>(relocAddress) = static_cast<uint32_t>(gpuAddressAs64bit & 0xffffffff);
break;
case RelocationInfo::Type::AddressHigh:
*reinterpret_cast<uint32_t *>(relocAddress) = static_cast<uint32_t>((gpuAddressAs64bit >> 32) & 0xffffffff);
break;
}
}
void Linker::patchInstructionsSegments(const std::vector<PatchableSegment> &instructionsSegments, std::vector<UnresolvedExternal> &outUnresolvedExternals) {
if (false == data.getTraits().requiresPatchingOfInstructionSegments) {
return;
}
UNRECOVERABLE_IF(data.getRelocationsInInstructionSegments().size() > instructionsSegments.size());
auto segIt = instructionsSegments.begin();
uint32_t segId = 0u;
for (auto relocsIt = data.getRelocationsInInstructionSegments().begin(), relocsEnd = data.getRelocationsInInstructionSegments().end();
relocsIt != relocsEnd; ++relocsIt, ++segIt, ++segId) {
auto &thisSegmentRelocs = *relocsIt;
const PatchableSegment &instSeg = *segIt;
for (const auto &relocation : thisSegmentRelocs) {
if (shouldIgnoreRelocation(relocation)) {
continue;
}
UNRECOVERABLE_IF(nullptr == instSeg.hostPointer);
auto relocAddress = ptrOffset(instSeg.hostPointer, static_cast<uintptr_t>(relocation.offset));
if (relocation.symbolName == implicitArgsRelocationSymbolName) {
pImplicitArgsRelocationAddresses.insert({segId, reinterpret_cast<uint32_t *>(relocAddress)});
continue;
}
auto symbolIt = relocatedSymbols.find(relocation.symbolName);
bool invalidOffset = relocation.offset + addressSizeInBytes(relocation.type) > instSeg.segmentSize;
bool unresolvedExternal = (symbolIt == relocatedSymbols.end());
DEBUG_BREAK_IF(invalidOffset);
if (invalidOffset || unresolvedExternal) {
uint32_t segId = static_cast<uint32_t>(segIt - instructionsSegments.begin());
outUnresolvedExternals.push_back(UnresolvedExternal{relocation, segId, invalidOffset});
continue;
}
patchAddress(relocAddress, symbolIt->second, relocation);
}
}
}
void Linker::patchDataSegments(const SegmentInfo &globalVariablesSegInfo, const SegmentInfo &globalConstantsSegInfo,
GraphicsAllocation *globalVariablesSeg, GraphicsAllocation *globalConstantsSeg,
std::vector<UnresolvedExternal> &outUnresolvedExternals, Device *pDevice,
const void *constantsInitData, const void *variablesInitData) {
for (const auto &relocation : data.getDataRelocations()) {
auto symbolIt = relocatedSymbols.find(relocation.symbolName);
if (symbolIt == relocatedSymbols.end()) {
outUnresolvedExternals.push_back(UnresolvedExternal{relocation});
continue;
}
uint64_t srcGpuAddressAs64Bit = symbolIt->second.gpuAddress;
GraphicsAllocation *dst = nullptr;
const void *initData = nullptr;
if (SegmentType::GlobalVariables == relocation.relocationSegment) {
dst = globalVariablesSeg;
initData = variablesInitData;
} else if (SegmentType::GlobalConstants == relocation.relocationSegment) {
dst = globalConstantsSeg;
initData = constantsInitData;
} else {
outUnresolvedExternals.push_back(UnresolvedExternal{relocation});
continue;
}
UNRECOVERABLE_IF(nullptr == dst);
auto relocType = (LinkerInput::Traits::PointerSize::Ptr32bit == data.getTraits().pointerSize) ? RelocationInfo::Type::AddressLow : relocation.type;
bool invalidOffset = relocation.offset + addressSizeInBytes(relocType) > dst->getUnderlyingBufferSize();
DEBUG_BREAK_IF(invalidOffset);
if (invalidOffset) {
outUnresolvedExternals.push_back(UnresolvedExternal{relocation});
continue;
}
uint64_t incrementValue = 0U;
switch (relocType) {
default:
UNRECOVERABLE_IF(RelocationInfo::Type::Address != relocType);
incrementValue = srcGpuAddressAs64Bit;
patchIncrement<uint64_t>(pDevice, dst, static_cast<size_t>(relocation.offset), initData, incrementValue);
break;
case RelocationInfo::Type::AddressLow:
incrementValue = srcGpuAddressAs64Bit & 0xffffffff;
patchIncrement<uint32_t>(pDevice, dst, static_cast<size_t>(relocation.offset), initData, incrementValue);
break;
case RelocationInfo::Type::AddressHigh:
incrementValue = (srcGpuAddressAs64Bit >> 32) & 0xffffffff;
patchIncrement<uint32_t>(pDevice, dst, static_cast<size_t>(relocation.offset), initData, incrementValue);
break;
}
}
}
std::string constructLinkerErrorMessage(const Linker::UnresolvedExternals &unresolvedExternals, const std::vector<std::string> &instructionsSegmentsNames) {
std::stringstream errorStream;
if (unresolvedExternals.size() == 0) {
errorStream << "Internal linker error";
} else {
for (const auto &unresExtern : unresolvedExternals) {
if (unresExtern.internalError) {
errorStream << "error : internal linker error while handling symbol ";
} else {
errorStream << "error : unresolved external symbol ";
}
if (unresExtern.unresolvedRelocation.relocationSegment == NEO::SegmentType::Instructions) {
errorStream << unresExtern.unresolvedRelocation.symbolName << " at offset " << unresExtern.unresolvedRelocation.offset
<< " in instructions segment #" << unresExtern.instructionsSegmentId;
if (instructionsSegmentsNames.size() > unresExtern.instructionsSegmentId) {
errorStream << " (aka " << instructionsSegmentsNames[unresExtern.instructionsSegmentId] << ")";
}
} else {
errorStream << " symbol #" << unresExtern.unresolvedRelocation.symbolName << " at offset " << unresExtern.unresolvedRelocation.offset
<< " in data segment #" << asString(unresExtern.unresolvedRelocation.relocationSegment);
}
errorStream << "\n";
}
}
return errorStream.str();
}
std::string constructRelocationsDebugMessage(const Linker::RelocatedSymbolsMap &relocatedSymbols) {
if (relocatedSymbols.empty()) {
return "";
}
std::stringstream stream;
stream << "Relocations debug informations :\n";
for (const auto &symbol : relocatedSymbols) {
stream << " * \"" << symbol.first << "\" [" << symbol.second.symbol.size << " bytes]";
stream << " " << asString(symbol.second.symbol.segment) << "_SEGMENT@" << symbol.second.symbol.offset;
stream << " -> " << std::hex << std::showbase << symbol.second.gpuAddress << " GPUVA" << std::dec;
stream << "\n";
}
return stream.str();
}
void Linker::applyDebugDataRelocations(const NEO::Elf::Elf<NEO::Elf::EI_CLASS_64> &decodedElf, ArrayRef<uint8_t> inputOutputElf, const SegmentInfo &text, const SegmentInfo &globalData, const SegmentInfo &constData) {
for (auto &reloc : decodedElf.getDebugInfoRelocations()) {
auto targetSectionName = decodedElf.getSectionName(reloc.targetSectionIndex);
auto sectionName = decodedElf.getSectionName(reloc.symbolSectionIndex);
auto symbolAddress = decodedElf.getSymbolValue(reloc.symbolTableIndex);
if (sectionName == Elf::SpecialSectionNames::text) {
symbolAddress += text.gpuAddress;
} else if (ConstStringRef(sectionName.c_str()).startsWith(Elf::SectionsNamesZebin::dataConst.data())) {
symbolAddress += constData.gpuAddress;
} else if (ConstStringRef(sectionName.c_str()).startsWith(Elf::SectionsNamesZebin::dataGlobal.data())) {
symbolAddress += globalData.gpuAddress;
} else {
// do not offset debug sections
if (!ConstStringRef(sectionName.c_str()).startsWith(Elf::SpecialSectionNames::debug.data())) {
// skip other sections
continue;
}
}
symbolAddress += reloc.addend;
auto targetSectionOffset = decodedElf.sectionHeaders[reloc.targetSectionIndex].header->offset;
auto relocLocation = reinterpret_cast<uint64_t>(inputOutputElf.begin()) + targetSectionOffset + reloc.offset;
if (static_cast<Elf::RELOCATION_X8664_TYPE>(reloc.relocType) == Elf::RELOCATION_X8664_TYPE::R_X8664_64) {
*reinterpret_cast<uint64_t *>(relocLocation) = symbolAddress;
} else if (static_cast<Elf::RELOCATION_X8664_TYPE>(reloc.relocType) == Elf::RELOCATION_X8664_TYPE::R_X8664_32) {
*reinterpret_cast<uint32_t *>(relocLocation) = static_cast<uint32_t>(symbolAddress & uint32_t(-1));
}
}
}
void Linker::resolveImplicitArgs(const KernelDescriptorsT &kernelDescriptors, Device *pDevice) {
for (auto i = 0u; i < kernelDescriptors.size(); i++) {
UNRECOVERABLE_IF(!kernelDescriptors[i]);
KernelDescriptor &kernelDescriptor = *kernelDescriptors[i];
auto pImplicitArgsReloc = pImplicitArgsRelocationAddresses.find(i);
if (pImplicitArgsReloc != pImplicitArgsRelocationAddresses.end()) {
UNRECOVERABLE_IF(!pDevice);
kernelDescriptor.kernelAttributes.flags.requiresImplicitArgs = kernelDescriptor.kernelAttributes.flags.useStackCalls || pDevice->getDebugger() != nullptr;
if (kernelDescriptor.kernelAttributes.flags.requiresImplicitArgs) {
*pImplicitArgsReloc->second = sizeof(ImplicitArgs);
} else {
*pImplicitArgsReloc->second = 0u;
}
}
}
}
void Linker::resolveBuiltins(Device *pDevice, UnresolvedExternals &outUnresolvedExternals, const std::vector<PatchableSegment> &instructionsSegments) {
int vecIndex = static_cast<int>(outUnresolvedExternals.size() - 1u);
for (; vecIndex >= 0; --vecIndex) {
if (outUnresolvedExternals[vecIndex].unresolvedRelocation.symbolName == subDeviceID) {
RelocatedSymbol symbol;
symbol.gpuAddress = static_cast<uintptr_t>(pDevice->getDefaultEngine().commandStreamReceiver->getWorkPartitionAllocationGpuAddress());
auto relocAddress = ptrOffset(instructionsSegments[outUnresolvedExternals[vecIndex].instructionsSegmentId].hostPointer,
static_cast<uintptr_t>(outUnresolvedExternals[vecIndex].unresolvedRelocation.offset));
NEO::Linker::patchAddress(relocAddress, symbol, outUnresolvedExternals[vecIndex].unresolvedRelocation);
outUnresolvedExternals[vecIndex] = outUnresolvedExternals[outUnresolvedExternals.size() - 1u];
outUnresolvedExternals.resize(outUnresolvedExternals.size() - 1u);
}
}
}
} // namespace NEO