diff options
Diffstat (limited to 'ELF/Target.h')
| -rw-r--r-- | ELF/Target.h | 231 |
1 files changed, 116 insertions, 115 deletions
diff --git a/ELF/Target.h b/ELF/Target.h index 685ad05ecd66..effa6001f6d9 100644 --- a/ELF/Target.h +++ b/ELF/Target.h @@ -1,9 +1,8 @@ //===- Target.h -------------------------------------------------*- C++ -*-===// // -// The LLVM Linker -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. +// 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 // //===----------------------------------------------------------------------===// @@ -17,7 +16,7 @@ #include <array> namespace lld { -std::string toString(elf::RelType Type); +std::string toString(elf::RelType type); namespace elf { class Defined; @@ -27,36 +26,39 @@ class Symbol; class TargetInfo { public: virtual uint32_t calcEFlags() const { return 0; } - virtual RelType getDynRel(RelType Type) const { return Type; } - virtual void writeGotPltHeader(uint8_t *Buf) const {} - virtual void writeGotHeader(uint8_t *Buf) const {} - virtual void writeGotPlt(uint8_t *Buf, const Symbol &S) const {}; - virtual void writeIgotPlt(uint8_t *Buf, const Symbol &S) const; - virtual int64_t getImplicitAddend(const uint8_t *Buf, RelType Type) const; + virtual RelExpr getRelExpr(RelType type, const Symbol &s, + const uint8_t *loc) const = 0; + virtual RelType getDynRel(RelType type) const { return 0; } + virtual void writeGotPltHeader(uint8_t *buf) const {} + virtual void writeGotHeader(uint8_t *buf) const {} + virtual void writeGotPlt(uint8_t *buf, const Symbol &s) const {}; + virtual void writeIgotPlt(uint8_t *buf, const Symbol &s) const; + virtual int64_t getImplicitAddend(const uint8_t *buf, RelType type) const; + virtual int getTlsGdRelaxSkip(RelType type) const { return 1; } // If lazy binding is supported, the first entry of the PLT has code // to call the dynamic linker to resolve PLT entries the first time // they are called. This function writes that code. - virtual void writePltHeader(uint8_t *Buf) const {} + virtual void writePltHeader(uint8_t *buf) const {} - virtual void writePlt(uint8_t *Buf, uint64_t GotEntryAddr, - uint64_t PltEntryAddr, int32_t Index, - unsigned RelOff) const {} - virtual void addPltHeaderSymbols(InputSection &IS) const {} - virtual void addPltSymbols(InputSection &IS, uint64_t Off) const {} + virtual void writePlt(uint8_t *buf, uint64_t gotEntryAddr, + uint64_t pltEntryAddr, int32_t index, + unsigned relOff) const {} + virtual void addPltHeaderSymbols(InputSection &isec) const {} + virtual void addPltSymbols(InputSection &isec, uint64_t off) const {} // Returns true if a relocation only uses the low bits of a value such that // all those bits are in the same page. For example, if the relocation // only uses the low 12 bits in a system with 4k pages. If this is true, the // bits will always have the same value at runtime and we don't have to emit // a dynamic relocation. - virtual bool usesOnlyLowPageBits(RelType Type) const; + virtual bool usesOnlyLowPageBits(RelType type) const; // Decide whether a Thunk is needed for the relocation from File // targeting S. - virtual bool needsThunk(RelExpr Expr, RelType RelocType, - const InputFile *File, uint64_t BranchAddr, - const Symbol &S) const; + virtual bool needsThunk(RelExpr expr, RelType relocType, + const InputFile *file, uint64_t branchAddr, + const Symbol &s) const; // On systems with range extensions we place collections of Thunks at // regular spacings that enable the majority of branches reach the Thunks. @@ -68,77 +70,71 @@ public: // to do the right thing. See https://gcc.gnu.org/wiki/SplitStacks. // The symbols st_other flags are needed on PowerPC64 for determining the // offset to the split-stack prologue. - virtual bool adjustPrologueForCrossSplitStack(uint8_t *Loc, uint8_t *End, - uint8_t StOther) const; + virtual bool adjustPrologueForCrossSplitStack(uint8_t *loc, uint8_t *end, + uint8_t stOther) const; - // Return true if we can reach Dst from Src with Relocation RelocType - virtual bool inBranchRange(RelType Type, uint64_t Src, - uint64_t Dst) const; - virtual RelExpr getRelExpr(RelType Type, const Symbol &S, - const uint8_t *Loc) const = 0; + // Return true if we can reach dst from src with RelType type. + virtual bool inBranchRange(RelType type, uint64_t src, + uint64_t dst) const; - virtual void relocateOne(uint8_t *Loc, RelType Type, uint64_t Val) const = 0; + virtual void relocateOne(uint8_t *loc, RelType type, uint64_t val) const = 0; virtual ~TargetInfo(); - unsigned TlsGdRelaxSkip = 1; - unsigned PageSize = 4096; - unsigned DefaultMaxPageSize = 4096; + unsigned defaultCommonPageSize = 4096; + unsigned defaultMaxPageSize = 4096; - uint64_t getImageBase(); + uint64_t getImageBase() const; - // Offset of _GLOBAL_OFFSET_TABLE_ from base of .got or .got.plt section. - uint64_t GotBaseSymOff = 0; // True if _GLOBAL_OFFSET_TABLE_ is relative to .got.plt, false if .got. - bool GotBaseSymInGotPlt = true; + bool gotBaseSymInGotPlt = true; - RelType CopyRel; - RelType GotRel; - RelType NoneRel; - RelType PltRel; - RelType RelativeRel; - RelType IRelativeRel; - RelType TlsDescRel; - RelType TlsGotRel; - RelType TlsModuleIndexRel; - RelType TlsOffsetRel; - unsigned GotEntrySize = 0; - unsigned GotPltEntrySize = 0; - unsigned PltEntrySize; - unsigned PltHeaderSize; + RelType copyRel; + RelType gotRel; + RelType noneRel; + RelType pltRel; + RelType relativeRel; + RelType iRelativeRel; + RelType symbolicRel; + RelType tlsDescRel; + RelType tlsGotRel; + RelType tlsModuleIndexRel; + RelType tlsOffsetRel; + unsigned pltEntrySize; + unsigned pltHeaderSize; // At least on x86_64 positions 1 and 2 are used by the first plt entry // to support lazy loading. - unsigned GotPltHeaderEntriesNum = 3; + unsigned gotPltHeaderEntriesNum = 3; // On PPC ELF V2 abi, the first entry in the .got is the .TOC. - unsigned GotHeaderEntriesNum = 0; + unsigned gotHeaderEntriesNum = 0; - bool NeedsThunks = false; + bool needsThunks = false; // A 4-byte field corresponding to one or more trap instructions, used to pad // executable OutputSections. - std::array<uint8_t, 4> TrapInstr; + std::array<uint8_t, 4> trapInstr; // If a target needs to rewrite calls to __morestack to instead call // __morestack_non_split when a split-stack enabled caller calls a // non-split-stack callee this will return true. Otherwise returns false. - bool NeedsMoreStackNonSplit = true; + bool needsMoreStackNonSplit = true; - virtual RelExpr adjustRelaxExpr(RelType Type, const uint8_t *Data, - RelExpr Expr) const; - virtual void relaxGot(uint8_t *Loc, uint64_t Val) const; - virtual void relaxTlsGdToIe(uint8_t *Loc, RelType Type, uint64_t Val) const; - virtual void relaxTlsGdToLe(uint8_t *Loc, RelType Type, uint64_t Val) const; - virtual void relaxTlsIeToLe(uint8_t *Loc, RelType Type, uint64_t Val) const; - virtual void relaxTlsLdToLe(uint8_t *Loc, RelType Type, uint64_t Val) const; + virtual RelExpr adjustRelaxExpr(RelType type, const uint8_t *data, + RelExpr expr) const; + virtual void relaxGot(uint8_t *loc, RelType type, uint64_t val) const; + virtual void relaxTlsGdToIe(uint8_t *loc, RelType type, uint64_t val) const; + virtual void relaxTlsGdToLe(uint8_t *loc, RelType type, uint64_t val) const; + virtual void relaxTlsIeToLe(uint8_t *loc, RelType type, uint64_t val) const; + virtual void relaxTlsLdToLe(uint8_t *loc, RelType type, uint64_t val) const; protected: // On FreeBSD x86_64 the first page cannot be mmaped. // On Linux that is controled by vm.mmap_min_addr. At least on some x86_64 // installs that is 65536, so the first 15 pages cannot be used. // Given that, the smallest value that can be used in here is 0x10000. - uint64_t DefaultImageBase = 0x10000; + uint64_t defaultImageBase = 0x10000; }; TargetInfo *getAArch64TargetInfo(); @@ -151,108 +147,113 @@ TargetInfo *getPPC64TargetInfo(); TargetInfo *getPPCTargetInfo(); TargetInfo *getRISCVTargetInfo(); TargetInfo *getSPARCV9TargetInfo(); -TargetInfo *getX32TargetInfo(); TargetInfo *getX86TargetInfo(); TargetInfo *getX86_64TargetInfo(); template <class ELFT> TargetInfo *getMipsTargetInfo(); struct ErrorPlace { - InputSectionBase *IS; - std::string Loc; + InputSectionBase *isec; + std::string loc; }; // Returns input section and corresponding source string for the given location. -ErrorPlace getErrorPlace(const uint8_t *Loc); +ErrorPlace getErrorPlace(const uint8_t *loc); -static inline std::string getErrorLocation(const uint8_t *Loc) { - return getErrorPlace(Loc).Loc; +static inline std::string getErrorLocation(const uint8_t *loc) { + return getErrorPlace(loc).loc; } -// In the PowerPC64 Elf V2 abi a function can have 2 entry points. The first is -// a global entry point (GEP) which typically is used to intiailzie the TOC +void writePPC32GlinkSection(uint8_t *buf, size_t numEntries); + +bool tryRelaxPPC64TocIndirection(RelType type, const Relocation &rel, + uint8_t *bufLoc); +unsigned getPPCDFormOp(unsigned secondaryOp); + +// In the PowerPC64 Elf V2 abi a function can have 2 entry points. The first +// is a global entry point (GEP) which typically is used to initialize the TOC // pointer in general purpose register 2. The second is a local entry // point (LEP) which bypasses the TOC pointer initialization code. The // offset between GEP and LEP is encoded in a function's st_other flags. // This function will return the offset (in bytes) from the global entry-point // to the local entry-point. -unsigned getPPC64GlobalEntryToLocalEntryOffset(uint8_t StOther); +unsigned getPPC64GlobalEntryToLocalEntryOffset(uint8_t stOther); + +// Returns true if a relocation is a small code model relocation that accesses +// the .toc section. +bool isPPC64SmallCodeModelTocReloc(RelType type); uint64_t getPPC64TocBase(); -uint64_t getAArch64Page(uint64_t Expr); +uint64_t getAArch64Page(uint64_t expr); -extern TargetInfo *Target; +extern const TargetInfo *target; TargetInfo *getTarget(); -template <class ELFT> bool isMipsPIC(const Defined *Sym); +template <class ELFT> bool isMipsPIC(const Defined *sym); -static inline void reportRangeError(uint8_t *Loc, RelType Type, const Twine &V, - int64_t Min, uint64_t Max) { - ErrorPlace ErrPlace = getErrorPlace(Loc); - StringRef Hint; - if (ErrPlace.IS && ErrPlace.IS->Name.startswith(".debug")) - Hint = "; consider recompiling with -fdebug-types-section to reduce size " +static inline void reportRangeError(uint8_t *loc, RelType type, const Twine &v, + int64_t min, uint64_t max) { + ErrorPlace errPlace = getErrorPlace(loc); + StringRef hint; + if (errPlace.isec && errPlace.isec->name.startswith(".debug")) + hint = "; consider recompiling with -fdebug-types-section to reduce size " "of debug sections"; - errorOrWarn(ErrPlace.Loc + "relocation " + lld::toString(Type) + - " out of range: " + V.str() + " is not in [" + Twine(Min).str() + - ", " + Twine(Max).str() + "]" + Hint); -} - -inline unsigned getPltEntryOffset(unsigned Idx) { - return Target->PltHeaderSize + Target->PltEntrySize * Idx; + errorOrWarn(errPlace.loc + "relocation " + lld::toString(type) + + " out of range: " + v.str() + " is not in [" + Twine(min).str() + + ", " + Twine(max).str() + "]" + hint); } // Make sure that V can be represented as an N bit signed integer. -inline void checkInt(uint8_t *Loc, int64_t V, int N, RelType Type) { - if (V != llvm::SignExtend64(V, N)) - reportRangeError(Loc, Type, Twine(V), llvm::minIntN(N), llvm::maxIntN(N)); +inline void checkInt(uint8_t *loc, int64_t v, int n, RelType type) { + if (v != llvm::SignExtend64(v, n)) + reportRangeError(loc, type, Twine(v), llvm::minIntN(n), llvm::maxIntN(n)); } // Make sure that V can be represented as an N bit unsigned integer. -inline void checkUInt(uint8_t *Loc, uint64_t V, int N, RelType Type) { - if ((V >> N) != 0) - reportRangeError(Loc, Type, Twine(V), 0, llvm::maxUIntN(N)); +inline void checkUInt(uint8_t *loc, uint64_t v, int n, RelType type) { + if ((v >> n) != 0) + reportRangeError(loc, type, Twine(v), 0, llvm::maxUIntN(n)); } // Make sure that V can be represented as an N bit signed or unsigned integer. -inline void checkIntUInt(uint8_t *Loc, uint64_t V, int N, RelType Type) { +inline void checkIntUInt(uint8_t *loc, uint64_t v, int n, RelType type) { // For the error message we should cast V to a signed integer so that error // messages show a small negative value rather than an extremely large one - if (V != (uint64_t)llvm::SignExtend64(V, N) && (V >> N) != 0) - reportRangeError(Loc, Type, Twine((int64_t)V), llvm::minIntN(N), - llvm::maxIntN(N)); + if (v != (uint64_t)llvm::SignExtend64(v, n) && (v >> n) != 0) + reportRangeError(loc, type, Twine((int64_t)v), llvm::minIntN(n), + llvm::maxUIntN(n)); } -inline void checkAlignment(uint8_t *Loc, uint64_t V, int N, RelType Type) { - if ((V & (N - 1)) != 0) - error(getErrorLocation(Loc) + "improper alignment for relocation " + - lld::toString(Type) + ": 0x" + llvm::utohexstr(V) + - " is not aligned to " + Twine(N) + " bytes"); +inline void checkAlignment(uint8_t *loc, uint64_t v, int n, RelType type) { + if ((v & (n - 1)) != 0) + error(getErrorLocation(loc) + "improper alignment for relocation " + + lld::toString(type) + ": 0x" + llvm::utohexstr(v) + + " is not aligned to " + Twine(n) + " bytes"); } // Endianness-aware read/write. -inline uint16_t read16(const void *P) { - return llvm::support::endian::read16(P, Config->Endianness); +inline uint16_t read16(const void *p) { + return llvm::support::endian::read16(p, config->endianness); } -inline uint32_t read32(const void *P) { - return llvm::support::endian::read32(P, Config->Endianness); +inline uint32_t read32(const void *p) { + return llvm::support::endian::read32(p, config->endianness); } -inline uint64_t read64(const void *P) { - return llvm::support::endian::read64(P, Config->Endianness); +inline uint64_t read64(const void *p) { + return llvm::support::endian::read64(p, config->endianness); } -inline void write16(void *P, uint16_t V) { - llvm::support::endian::write16(P, V, Config->Endianness); +inline void write16(void *p, uint16_t v) { + llvm::support::endian::write16(p, v, config->endianness); } -inline void write32(void *P, uint32_t V) { - llvm::support::endian::write32(P, V, Config->Endianness); +inline void write32(void *p, uint32_t v) { + llvm::support::endian::write32(p, v, config->endianness); } -inline void write64(void *P, uint64_t V) { - llvm::support::endian::write64(P, V, Config->Endianness); +inline void write64(void *p, uint64_t v) { + llvm::support::endian::write64(p, v, config->endianness); } } // namespace elf } // namespace lld |
