llvm-project/lld/ELF/Config.h

334 lines
9.9 KiB
C++

//===- Config.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 LLD_ELF_CONFIG_H
#define LLD_ELF_CONFIG_H
#include "lld/Common/ErrorHandler.h"
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/BinaryFormat/ELF.h"
#include "llvm/Support/CachePruning.h"
#include "llvm/Support/CodeGen.h"
#include "llvm/Support/Endian.h"
#include <atomic>
#include <vector>
namespace lld {
namespace elf {
class InputFile;
class InputSectionBase;
enum ELFKind {
ELFNoneKind,
ELF32LEKind,
ELF32BEKind,
ELF64LEKind,
ELF64BEKind
};
// For --build-id.
enum class BuildIdKind { None, Fast, Md5, Sha1, Hexstring, Uuid };
// For --discard-{all,locals,none}.
enum class DiscardPolicy { Default, All, Locals, None };
// For --icf={none,safe,all}.
enum class ICFLevel { None, Safe, All };
// For --strip-{all,debug}.
enum class StripPolicy { None, All, Debug };
// For --unresolved-symbols.
enum class UnresolvedPolicy { ReportError, Warn, Ignore };
// For --orphan-handling.
enum class OrphanHandlingPolicy { Place, Warn, Error };
// For --sort-section and linkerscript sorting rules.
enum class SortSectionPolicy { Default, None, Alignment, Name, Priority };
// For --target2
enum class Target2Policy { Abs, Rel, GotRel };
// For tracking ARM Float Argument PCS
enum class ARMVFPArgKind { Default, Base, VFP, ToolChain };
// For -z noseparate-code, -z separate-code and -z separate-loadable-segments.
enum class SeparateSegmentKind { None, Code, Loadable };
// For -z *stack
enum class GnuStackKind { None, Exec, NoExec };
struct SymbolVersion {
llvm::StringRef name;
bool isExternCpp;
bool hasWildcard;
};
// This struct contains symbols version definition that
// can be found in version script if it is used for link.
struct VersionDefinition {
llvm::StringRef name;
uint16_t id;
std::vector<SymbolVersion> patterns;
};
// This struct contains the global configuration for the linker.
// Most fields are direct mapping from the command line options
// and such fields have the same name as the corresponding options.
// Most fields are initialized by the driver.
struct Configuration {
uint8_t osabi = 0;
uint32_t andFeatures = 0;
llvm::CachePruningPolicy thinLTOCachePolicy;
llvm::StringMap<uint64_t> sectionStartMap;
llvm::StringRef chroot;
llvm::StringRef dynamicLinker;
llvm::StringRef dwoDir;
llvm::StringRef entry;
llvm::StringRef emulation;
llvm::StringRef fini;
llvm::StringRef init;
llvm::StringRef ltoAAPipeline;
llvm::StringRef ltoCSProfileFile;
llvm::StringRef ltoNewPmPasses;
llvm::StringRef ltoObjPath;
llvm::StringRef ltoSampleProfile;
llvm::StringRef mapFile;
llvm::StringRef outputFile;
llvm::StringRef optRemarksFilename;
llvm::StringRef optRemarksPasses;
llvm::StringRef optRemarksFormat;
llvm::StringRef progName;
llvm::StringRef printSymbolOrder;
llvm::StringRef soName;
llvm::StringRef sysroot;
llvm::StringRef thinLTOCacheDir;
llvm::StringRef thinLTOIndexOnlyArg;
std::pair<llvm::StringRef, llvm::StringRef> thinLTOObjectSuffixReplace;
std::pair<llvm::StringRef, llvm::StringRef> thinLTOPrefixReplace;
std::string rpath;
std::vector<VersionDefinition> versionDefinitions;
std::vector<llvm::StringRef> auxiliaryList;
std::vector<llvm::StringRef> filterList;
std::vector<llvm::StringRef> searchPaths;
std::vector<llvm::StringRef> symbolOrderingFile;
std::vector<llvm::StringRef> undefined;
std::vector<SymbolVersion> dynamicList;
std::vector<uint8_t> buildIdVector;
llvm::MapVector<std::pair<const InputSectionBase *, const InputSectionBase *>,
uint64_t>
callGraphProfile;
bool allowMultipleDefinition;
bool allowShlibUndefined;
bool androidPackDynRelocs;
bool armHasBlx = false;
bool armHasMovtMovw = false;
bool armJ1J2BranchEncoding = false;
bool asNeeded = false;
bool bsymbolic;
bool bsymbolicFunctions;
bool callGraphProfileSort;
bool checkSections;
bool compressDebugSections;
bool cref;
bool defineCommon;
bool demangle = true;
bool dependentLibraries;
bool disableVerify;
bool ehFrameHdr;
bool emitLLVM;
bool emitRelocs;
bool enableNewDtags;
bool executeOnly;
bool exportDynamic;
bool fixCortexA53Errata843419;
bool fixCortexA8;
bool forceBTI;
bool formatBinary = false;
bool requireCET;
bool gcSections;
bool gdbIndex;
bool gnuHash = false;
bool gnuUnique;
bool hasDynamicList = false;
bool hasDynSymTab;
bool ignoreDataAddressEquality;
bool ignoreFunctionAddressEquality;
bool ltoCSProfileGenerate;
bool ltoDebugPassManager;
bool ltoNewPassManager;
bool mergeArmExidx;
bool mipsN32Abi = false;
bool mmapOutputFile;
bool nmagic;
bool noinhibitExec;
bool nostdlib;
bool oFormatBinary;
bool omagic;
bool optRemarksWithHotness;
bool pacPlt;
bool picThunk;
bool pie;
bool printGcSections;
bool printIcfSections;
bool relocatable;
bool relrPackDynRelocs;
bool saveTemps;
bool singleRoRx;
bool shared;
bool isStatic = false;
bool sysvHash = false;
bool target1Rel;
bool trace;
bool thinLTOEmitImportsFiles;
bool thinLTOIndexOnly;
bool tocOptimize;
bool undefinedVersion;
bool useAndroidRelrTags = false;
bool warnBackrefs;
bool warnCommon;
bool warnIfuncTextrel;
bool warnMissingEntry;
bool warnSymbolOrdering;
bool writeAddends;
bool zCombreloc;
bool zCopyreloc;
bool zGlobal;
bool zHazardplt;
bool zIfuncNoplt;
bool zInitfirst;
bool zInterpose;
bool zKeepTextSectionPrefix;
bool zNodefaultlib;
bool zNodelete;
bool zNodlopen;
bool zNow;
bool zOrigin;
bool zRelro;
bool zRodynamic;
bool zText;
bool zRetpolineplt;
bool zWxneeded;
DiscardPolicy discard;
GnuStackKind zGnustack;
ICFLevel icf;
OrphanHandlingPolicy orphanHandling;
SortSectionPolicy sortSection;
StripPolicy strip;
UnresolvedPolicy unresolvedSymbols;
Target2Policy target2;
ARMVFPArgKind armVFPArgs = ARMVFPArgKind::Default;
BuildIdKind buildId = BuildIdKind::None;
SeparateSegmentKind zSeparate;
ELFKind ekind = ELFNoneKind;
uint16_t emachine = llvm::ELF::EM_NONE;
llvm::Optional<uint64_t> imageBase;
uint64_t commonPageSize;
uint64_t maxPageSize;
uint64_t mipsGotSize;
uint64_t zStackSize;
unsigned ltoPartitions;
unsigned ltoo;
unsigned optimize;
unsigned thinLTOJobs;
int32_t splitStackAdjustSize;
// The following config options do not directly correspond to any
// particular command line options.
// True if we need to pass through relocations in input files to the
// output file. Usually false because we consume relocations.
bool copyRelocs;
// True if the target is ELF64. False if ELF32.
bool is64;
// True if the target is little-endian. False if big-endian.
bool isLE;
// endianness::little if isLE is true. endianness::big otherwise.
llvm::support::endianness endianness;
// True if the target is the little-endian MIPS64.
//
// The reason why we have this variable only for the MIPS is because
// we use this often. Some ELF headers for MIPS64EL are in a
// mixed-endian (which is horrible and I'd say that's a serious spec
// bug), and we need to know whether we are reading MIPS ELF files or
// not in various places.
//
// (Note that MIPS64EL is not a typo for MIPS64LE. This is the official
// name whatever that means. A fun hypothesis is that "EL" is short for
// little-endian written in the little-endian order, but I don't know
// if that's true.)
bool isMips64EL;
// True if we need to set the DF_STATIC_TLS flag to an output file,
// which works as a hint to the dynamic loader that the file contains
// code compiled with the static TLS model. The thread-local variable
// compiled with the static TLS model is faster but less flexible, and
// it may not be loaded using dlopen().
//
// We set this flag to true when we see a relocation for the static TLS
// model. Once this becomes true, it will never become false.
//
// Since the flag is updated by multi-threaded code, we use std::atomic.
// (Writing to a variable is not considered thread-safe even if the
// variable is boolean and we always set the same value from all threads.)
std::atomic<bool> hasStaticTlsModel{false};
// Holds set of ELF header flags for the target.
uint32_t eflags = 0;
// The ELF spec defines two types of relocation table entries, RELA and
// REL. RELA is a triplet of (offset, info, addend) while REL is a
// tuple of (offset, info). Addends for REL are implicit and read from
// the location where the relocations are applied. So, REL is more
// compact than RELA but requires a bit of more work to process.
//
// (From the linker writer's view, this distinction is not necessary.
// If the ELF had chosen whichever and sticked with it, it would have
// been easier to write code to process relocations, but it's too late
// to change the spec.)
//
// Each ABI defines its relocation type. IsRela is true if target
// uses RELA. As far as we know, all 64-bit ABIs are using RELA. A
// few 32-bit ABIs are using RELA too.
bool isRela;
// True if we are creating position-independent code.
bool isPic;
// 4 for ELF32, 8 for ELF64.
int wordsize;
};
// The only instance of Configuration struct.
extern Configuration *config;
// The first two elements of versionDefinitions represent VER_NDX_LOCAL and
// VER_NDX_GLOBAL. This helper returns other elements.
static inline ArrayRef<VersionDefinition> namedVersionDefs() {
return llvm::makeArrayRef(config->versionDefinitions).slice(2);
}
static inline void errorOrWarn(const Twine &msg) {
if (!config->noinhibitExec)
error(msg);
else
warn(msg);
}
} // namespace elf
} // namespace lld
#endif