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-rw-r--r--ELF/InputSection.cpp459
1 files changed, 271 insertions, 188 deletions
diff --git a/ELF/InputSection.cpp b/ELF/InputSection.cpp
index 54fb57cf9888a..839bff7011eb8 100644
--- a/ELF/InputSection.cpp
+++ b/ELF/InputSection.cpp
@@ -21,7 +21,6 @@
#include "Thunks.h"
#include "lld/Common/ErrorHandler.h"
#include "lld/Common/Memory.h"
-#include "llvm/Object/Decompressor.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Compression.h"
#include "llvm/Support/Endian.h"
@@ -64,11 +63,11 @@ InputSectionBase::InputSectionBase(InputFile *File, uint64_t Flags,
StringRef Name, Kind SectionKind)
: SectionBase(SectionKind, Name, Flags, Entsize, Alignment, Type, Info,
Link),
- File(File), Data(Data) {
+ File(File), RawData(Data) {
// In order to reduce memory allocation, we assume that mergeable
// sections are smaller than 4 GiB, which is not an unreasonable
// assumption as of 2017.
- if (SectionKind == SectionBase::Merge && Data.size() > UINT32_MAX)
+ if (SectionKind == SectionBase::Merge && RawData.size() > UINT32_MAX)
error(toString(this) + ": section too large");
NumRelocations = 0;
@@ -80,6 +79,17 @@ InputSectionBase::InputSectionBase(InputFile *File, uint64_t Flags,
if (!isPowerOf2_64(V))
fatal(toString(File) + ": section sh_addralign is not a power of 2");
this->Alignment = V;
+
+ // In ELF, each section can be compressed by zlib, and if compressed,
+ // section name may be mangled by appending "z" (e.g. ".zdebug_info").
+ // If that's the case, demangle section name so that we can handle a
+ // section as if it weren't compressed.
+ if ((Flags & SHF_COMPRESSED) || Name.startswith(".zdebug")) {
+ if (!zlib::isAvailable())
+ error(toString(File) + ": contains a compressed section, " +
+ "but zlib is not available");
+ parseCompressedHeader();
+ }
}
// Drop SHF_GROUP bit unless we are producing a re-linkable object file.
@@ -128,13 +138,25 @@ InputSectionBase::InputSectionBase(ObjFile<ELFT> &File,
size_t InputSectionBase::getSize() const {
if (auto *S = dyn_cast<SyntheticSection>(this))
return S->getSize();
+ if (UncompressedSize >= 0)
+ return UncompressedSize;
+ return RawData.size();
+}
+
+void InputSectionBase::uncompress() const {
+ size_t Size = UncompressedSize;
+ UncompressedBuf.reset(new char[Size]);
- return Data.size();
+ if (Error E =
+ zlib::uncompress(toStringRef(RawData), UncompressedBuf.get(), Size))
+ fatal(toString(this) +
+ ": uncompress failed: " + llvm::toString(std::move(E)));
+ RawData = makeArrayRef((uint8_t *)UncompressedBuf.get(), Size);
}
uint64_t InputSectionBase::getOffsetInFile() const {
const uint8_t *FileStart = (const uint8_t *)File->MB.getBufferStart();
- const uint8_t *SecStart = Data.begin();
+ const uint8_t *SecStart = data().begin();
return SecStart - FileStart;
}
@@ -180,34 +202,70 @@ OutputSection *SectionBase::getOutputSection() {
return Sec ? Sec->getParent() : nullptr;
}
-// Decompress section contents if required. Note that this function
-// is called from parallelForEach, so it must be thread-safe.
-void InputSectionBase::maybeDecompress() {
- if (DecompressBuf)
- return;
- if (!(Flags & SHF_COMPRESSED) && !Name.startswith(".zdebug"))
- return;
+// When a section is compressed, `RawData` consists with a header followed
+// by zlib-compressed data. This function parses a header to initialize
+// `UncompressedSize` member and remove the header from `RawData`.
+void InputSectionBase::parseCompressedHeader() {
+ typedef typename ELF64LE::Chdr Chdr64;
+ typedef typename ELF32LE::Chdr Chdr32;
- // Decompress a section.
- Decompressor Dec = check(Decompressor::create(Name, toStringRef(Data),
- Config->IsLE, Config->Is64));
+ // Old-style header
+ if (Name.startswith(".zdebug")) {
+ if (!toStringRef(RawData).startswith("ZLIB")) {
+ error(toString(this) + ": corrupted compressed section header");
+ return;
+ }
+ RawData = RawData.slice(4);
- size_t Size = Dec.getDecompressedSize();
- DecompressBuf.reset(new char[Size + Name.size()]());
- if (Error E = Dec.decompress({DecompressBuf.get(), Size}))
- fatal(toString(this) +
- ": decompress failed: " + llvm::toString(std::move(E)));
+ if (RawData.size() < 8) {
+ error(toString(this) + ": corrupted compressed section header");
+ return;
+ }
+
+ UncompressedSize = read64be(RawData.data());
+ RawData = RawData.slice(8);
+
+ // Restore the original section name.
+ // (e.g. ".zdebug_info" -> ".debug_info")
+ Name = Saver.save("." + Name.substr(2));
+ return;
+ }
- Data = makeArrayRef((uint8_t *)DecompressBuf.get(), Size);
+ assert(Flags & SHF_COMPRESSED);
Flags &= ~(uint64_t)SHF_COMPRESSED;
- // A section name may have been altered if compressed. If that's
- // the case, restore the original name. (i.e. ".zdebug_" -> ".debug_")
- if (Name.startswith(".zdebug")) {
- DecompressBuf[Size] = '.';
- memcpy(&DecompressBuf[Size + 1], Name.data() + 2, Name.size() - 2);
- Name = StringRef(&DecompressBuf[Size], Name.size() - 1);
+ // New-style 64-bit header
+ if (Config->Is64) {
+ if (RawData.size() < sizeof(Chdr64)) {
+ error(toString(this) + ": corrupted compressed section");
+ return;
+ }
+
+ auto *Hdr = reinterpret_cast<const Chdr64 *>(RawData.data());
+ if (Hdr->ch_type != ELFCOMPRESS_ZLIB) {
+ error(toString(this) + ": unsupported compression type");
+ return;
+ }
+
+ UncompressedSize = Hdr->ch_size;
+ RawData = RawData.slice(sizeof(*Hdr));
+ return;
}
+
+ // New-style 32-bit header
+ if (RawData.size() < sizeof(Chdr32)) {
+ error(toString(this) + ": corrupted compressed section");
+ return;
+ }
+
+ auto *Hdr = reinterpret_cast<const Chdr32 *>(RawData.data());
+ if (Hdr->ch_type != ELFCOMPRESS_ZLIB) {
+ error(toString(this) + ": unsupported compression type");
+ return;
+ }
+
+ UncompressedSize = Hdr->ch_size;
+ RawData = RawData.slice(sizeof(*Hdr));
}
InputSection *InputSectionBase::getLinkOrderDep() const {
@@ -230,14 +288,17 @@ Defined *InputSectionBase::getEnclosingFunction(uint64_t Offset) {
// Returns a source location string. Used to construct an error message.
template <class ELFT>
std::string InputSectionBase::getLocation(uint64_t Offset) {
+ std::string SecAndOffset = (Name + "+0x" + utohexstr(Offset)).str();
+
// We don't have file for synthetic sections.
if (getFile<ELFT>() == nullptr)
- return (Config->OutputFile + ":(" + Name + "+0x" + utohexstr(Offset) + ")")
+ return (Config->OutputFile + ":(" + SecAndOffset + ")")
.str();
// First check if we can get desired values from debugging information.
if (Optional<DILineInfo> Info = getFile<ELFT>()->getDILineInfo(this, Offset))
- return Info->FileName + ":" + std::to_string(Info->Line);
+ return Info->FileName + ":" + std::to_string(Info->Line) + ":(" +
+ SecAndOffset + ")";
// File->SourceFile contains STT_FILE symbol that contains a
// source file name. If it's missing, we use an object file name.
@@ -246,10 +307,10 @@ std::string InputSectionBase::getLocation(uint64_t Offset) {
SrcFile = toString(File);
if (Defined *D = getEnclosingFunction<ELFT>(Offset))
- return SrcFile + ":(function " + toString(*D) + ")";
+ return SrcFile + ":(function " + toString(*D) + ": " + SecAndOffset + ")";
// If there's no symbol, print out the offset in the section.
- return (SrcFile + ":(" + Name + "+0x" + utohexstr(Offset) + ")").str();
+ return (SrcFile + ":(" + SecAndOffset + ")");
}
// This function is intended to be used for constructing an error message.
@@ -259,9 +320,6 @@ std::string InputSectionBase::getLocation(uint64_t Offset) {
//
// Returns an empty string if there's no way to get line info.
std::string InputSectionBase::getSrcMsg(const Symbol &Sym, uint64_t Offset) {
- // Synthetic sections don't have input files.
- if (!File)
- return "";
return File->getSrcMsg(Sym, *this, Offset);
}
@@ -275,9 +333,6 @@ std::string InputSectionBase::getSrcMsg(const Symbol &Sym, uint64_t Offset) {
//
// path/to/foo.o:(function bar) in archive path/to/bar.a
std::string InputSectionBase::getObjMsg(uint64_t Off) {
- // Synthetic sections don't have input files.
- if (!File)
- return ("<internal>:(" + Name + "+0x" + utohexstr(Off) + ")").str();
std::string Filename = File->getName();
std::string Archive;
@@ -362,7 +417,7 @@ void InputSection::copyRelocations(uint8_t *Buf, ArrayRef<RelTy> Rels) {
// Output section VA is zero for -r, so r_offset is an offset within the
// section, but for --emit-relocs it is an virtual address.
P->r_offset = Sec->getVA(Rel.r_offset);
- P->setSymbolAndType(InX::SymTab->getSymbolIndex(&Sym), Type,
+ P->setSymbolAndType(In.SymTab->getSymbolIndex(&Sym), Type,
Config->IsMips64EL);
if (Sym.Type == STT_SECTION) {
@@ -380,14 +435,14 @@ void InputSection::copyRelocations(uint8_t *Buf, ArrayRef<RelTy> Rels) {
error("STT_SECTION symbol should be defined");
continue;
}
- SectionBase *Section = D->Section;
- if (Section == &InputSection::Discarded) {
+ SectionBase *Section = D->Section->Repl;
+ if (!Section->Live) {
P->setSymbolAndType(0, 0, false);
continue;
}
int64_t Addend = getAddend<ELFT>(Rel);
- const uint8_t *BufLoc = Sec->Data.begin() + Rel.r_offset;
+ const uint8_t *BufLoc = Sec->data().begin() + Rel.r_offset;
if (!RelTy::IsRela)
Addend = Target->getImplicitAddend(BufLoc, Type);
@@ -487,6 +542,62 @@ static uint64_t getARMStaticBase(const Symbol &Sym) {
return OS->PtLoad->FirstSec->Addr;
}
+// For R_RISCV_PC_INDIRECT (R_RISCV_PCREL_LO12_{I,S}), the symbol actually
+// points the corresponding R_RISCV_PCREL_HI20 relocation, and the target VA
+// is calculated using PCREL_HI20's symbol.
+//
+// This function returns the R_RISCV_PCREL_HI20 relocation from
+// R_RISCV_PCREL_LO12's symbol and addend.
+static Relocation *getRISCVPCRelHi20(const Symbol *Sym, uint64_t Addend) {
+ const Defined *D = cast<Defined>(Sym);
+ InputSection *IS = cast<InputSection>(D->Section);
+
+ if (Addend != 0)
+ warn("Non-zero addend in R_RISCV_PCREL_LO12 relocation to " +
+ IS->getObjMsg(D->Value) + " is ignored");
+
+ // Relocations are sorted by offset, so we can use std::equal_range to do
+ // binary search.
+ auto Range = std::equal_range(IS->Relocations.begin(), IS->Relocations.end(),
+ D->Value, RelocationOffsetComparator{});
+ for (auto It = std::get<0>(Range); It != std::get<1>(Range); ++It)
+ if (isRelExprOneOf<R_PC>(It->Expr))
+ return &*It;
+
+ error("R_RISCV_PCREL_LO12 relocation points to " + IS->getObjMsg(D->Value) +
+ " without an associated R_RISCV_PCREL_HI20 relocation");
+ return nullptr;
+}
+
+// A TLS symbol's virtual address is relative to the TLS segment. Add a
+// target-specific adjustment to produce a thread-pointer-relative offset.
+static int64_t getTlsTpOffset() {
+ switch (Config->EMachine) {
+ case EM_ARM:
+ case EM_AARCH64:
+ // Variant 1. The thread pointer points to a TCB with a fixed 2-word size,
+ // followed by a variable amount of alignment padding, followed by the TLS
+ // segment.
+ //
+ // NB: While the ARM/AArch64 ABI formally has a 2-word TCB size, lld
+ // effectively increases the TCB size to 8 words for Android compatibility.
+ // It accomplishes this by increasing the segment's alignment.
+ return alignTo(Config->Wordsize * 2, Out::TlsPhdr->p_align);
+ case EM_386:
+ case EM_X86_64:
+ // Variant 2. The TLS segment is located just before the thread pointer.
+ return -Out::TlsPhdr->p_memsz;
+ case EM_PPC64:
+ // The thread pointer points to a fixed offset from the start of the
+ // executable's TLS segment. An offset of 0x7000 allows a signed 16-bit
+ // offset to reach 0x1000 of TCB/thread-library data and 0xf000 of the
+ // program's TLS segment.
+ return -0x7000;
+ default:
+ llvm_unreachable("unhandled Config->EMachine");
+ }
+}
+
static uint64_t getRelocTargetVA(const InputFile *File, RelType Type, int64_t A,
uint64_t P, const Symbol &Sym, RelExpr Expr) {
switch (Expr) {
@@ -501,38 +612,37 @@ static uint64_t getRelocTargetVA(const InputFile *File, RelType Type, int64_t A,
case R_ARM_SBREL:
return Sym.getVA(A) - getARMStaticBase(Sym);
case R_GOT:
+ case R_GOT_PLT:
case R_RELAX_TLS_GD_TO_IE_ABS:
return Sym.getGotVA() + A;
case R_GOTONLY_PC:
- return InX::Got->getVA() + A - P;
+ return In.Got->getVA() + A - P;
case R_GOTONLY_PC_FROM_END:
- return InX::Got->getVA() + A - P + InX::Got->getSize();
+ return In.Got->getVA() + A - P + In.Got->getSize();
case R_GOTREL:
- return Sym.getVA(A) - InX::Got->getVA();
+ return Sym.getVA(A) - In.Got->getVA();
case R_GOTREL_FROM_END:
- return Sym.getVA(A) - InX::Got->getVA() - InX::Got->getSize();
+ return Sym.getVA(A) - In.Got->getVA() - In.Got->getSize();
case R_GOT_FROM_END:
case R_RELAX_TLS_GD_TO_IE_END:
- return Sym.getGotOffset() + A - InX::Got->getSize();
+ return Sym.getGotOffset() + A - In.Got->getSize();
case R_TLSLD_GOT_OFF:
case R_GOT_OFF:
case R_RELAX_TLS_GD_TO_IE_GOT_OFF:
return Sym.getGotOffset() + A;
- case R_GOT_PAGE_PC:
- case R_RELAX_TLS_GD_TO_IE_PAGE_PC:
+ case R_AARCH64_GOT_PAGE_PC:
+ case R_AARCH64_GOT_PAGE_PC_PLT:
+ case R_AARCH64_RELAX_TLS_GD_TO_IE_PAGE_PC:
return getAArch64Page(Sym.getGotVA() + A) - getAArch64Page(P);
case R_GOT_PC:
case R_RELAX_TLS_GD_TO_IE:
return Sym.getGotVA() + A - P;
- case R_HINT:
- case R_NONE:
- case R_TLSDESC_CALL:
- case R_TLSLD_HINT:
- llvm_unreachable("cannot relocate hint relocs");
+ case R_HEXAGON_GOT:
+ return Sym.getGotVA() - In.GotPlt->getVA();
case R_MIPS_GOTREL:
- return Sym.getVA(A) - InX::MipsGot->getGp(File);
+ return Sym.getVA(A) - In.MipsGot->getGp(File);
case R_MIPS_GOT_GP:
- return InX::MipsGot->getGp(File) + A;
+ return In.MipsGot->getGp(File) + A;
case R_MIPS_GOT_GP_PC: {
// R_MIPS_LO16 expression has R_MIPS_GOT_GP_PC type iif the target
// is _gp_disp symbol. In that case we should use the following
@@ -541,7 +651,7 @@ static uint64_t getRelocTargetVA(const InputFile *File, RelType Type, int64_t A,
// microMIPS variants of these relocations use slightly different
// expressions: AHL + GP - P + 3 for %lo() and AHL + GP - P - 1 for %hi()
// to correctly handle less-sugnificant bit of the microMIPS symbol.
- uint64_t V = InX::MipsGot->getGp(File) + A - P;
+ uint64_t V = In.MipsGot->getGp(File) + A - P;
if (Type == R_MIPS_LO16 || Type == R_MICROMIPS_LO16)
V += 4;
if (Type == R_MICROMIPS_LO16 || Type == R_MICROMIPS_HI16)
@@ -552,31 +662,34 @@ static uint64_t getRelocTargetVA(const InputFile *File, RelType Type, int64_t A,
// If relocation against MIPS local symbol requires GOT entry, this entry
// should be initialized by 'page address'. This address is high 16-bits
// of sum the symbol's value and the addend.
- return InX::MipsGot->getVA() +
- InX::MipsGot->getPageEntryOffset(File, Sym, A) -
- InX::MipsGot->getGp(File);
+ return In.MipsGot->getVA() + In.MipsGot->getPageEntryOffset(File, Sym, A) -
+ In.MipsGot->getGp(File);
case R_MIPS_GOT_OFF:
case R_MIPS_GOT_OFF32:
// In case of MIPS if a GOT relocation has non-zero addend this addend
// should be applied to the GOT entry content not to the GOT entry offset.
// That is why we use separate expression type.
- return InX::MipsGot->getVA() +
- InX::MipsGot->getSymEntryOffset(File, Sym, A) -
- InX::MipsGot->getGp(File);
+ return In.MipsGot->getVA() + In.MipsGot->getSymEntryOffset(File, Sym, A) -
+ In.MipsGot->getGp(File);
case R_MIPS_TLSGD:
- return InX::MipsGot->getVA() + InX::MipsGot->getGlobalDynOffset(File, Sym) -
- InX::MipsGot->getGp(File);
+ return In.MipsGot->getVA() + In.MipsGot->getGlobalDynOffset(File, Sym) -
+ In.MipsGot->getGp(File);
case R_MIPS_TLSLD:
- return InX::MipsGot->getVA() + InX::MipsGot->getTlsIndexOffset(File) -
- InX::MipsGot->getGp(File);
- case R_PAGE_PC:
- case R_PLT_PAGE_PC: {
- uint64_t Dest;
- if (Sym.isUndefWeak())
- Dest = getAArch64Page(A);
- else
- Dest = getAArch64Page(Sym.getVA(A));
- return Dest - getAArch64Page(P);
+ return In.MipsGot->getVA() + In.MipsGot->getTlsIndexOffset(File) -
+ In.MipsGot->getGp(File);
+ case R_AARCH64_PAGE_PC: {
+ uint64_t Val = Sym.isUndefWeak() ? P + A : Sym.getVA(A);
+ return getAArch64Page(Val) - getAArch64Page(P);
+ }
+ case R_AARCH64_PLT_PAGE_PC: {
+ uint64_t Val = Sym.isUndefWeak() ? P + A : Sym.getPltVA() + A;
+ return getAArch64Page(Val) - getAArch64Page(P);
+ }
+ case R_RISCV_PC_INDIRECT: {
+ if (const Relocation *HiRel = getRISCVPCRelHi20(&Sym, A))
+ return getRelocTargetVA(File, HiRel->Type, HiRel->Addend, Sym.getVA(),
+ *HiRel->Sym, HiRel->Expr);
+ return 0;
}
case R_PC: {
uint64_t Dest;
@@ -608,16 +721,12 @@ static uint64_t getRelocTargetVA(const InputFile *File, RelType Type, int64_t A,
return 0;
// PPC64 V2 ABI describes two entry points to a function. The global entry
- // point sets up the TOC base pointer. When calling a local function, the
- // call should branch to the local entry point rather than the global entry
- // point. Section 3.4.1 describes using the 3 most significant bits of the
- // st_other field to find out how many instructions there are between the
- // local and global entry point.
- uint8_t StOther = (Sym.StOther >> 5) & 7;
- if (StOther == 0 || StOther == 1)
- return SymVA - P;
-
- return SymVA - P + (1LL << StOther);
+ // point is used for calls where the caller and callee (may) have different
+ // TOC base pointers and r2 needs to be modified to hold the TOC base for
+ // the callee. For local calls the caller and callee share the same
+ // TOC base and so the TOC pointer initialization code should be skipped by
+ // branching to the local entry point.
+ return SymVA - P + getPPC64GlobalEntryToLocalEntryOffset(Sym.StOther);
}
case R_PPC_TOC:
return getPPC64TocBase() + A;
@@ -634,48 +743,32 @@ static uint64_t getRelocTargetVA(const InputFile *File, RelType Type, int64_t A,
// statically to zero.
if (Sym.isTls() && Sym.isUndefWeak())
return 0;
-
- // For TLS variant 1 the TCB is a fixed size, whereas for TLS variant 2 the
- // TCB is on unspecified size and content. Targets that implement variant 1
- // should set TcbSize.
- if (Target->TcbSize) {
- // PPC64 V2 ABI has the thread pointer offset into the middle of the TLS
- // storage area by TlsTpOffset for efficient addressing TCB and up to
- // 4KB – 8 B of other thread library information (placed before the TCB).
- // Subtracting this offset will get the address of the first TLS block.
- if (Target->TlsTpOffset)
- return Sym.getVA(A) - Target->TlsTpOffset;
-
- // If thread pointer is not offset into the middle, the first thing in the
- // TLS storage area is the TCB. Add the TcbSize to get the address of the
- // first TLS block.
- return Sym.getVA(A) + alignTo(Target->TcbSize, Out::TlsPhdr->p_align);
- }
- return Sym.getVA(A) - Out::TlsPhdr->p_memsz;
+ return Sym.getVA(A) + getTlsTpOffset();
case R_RELAX_TLS_GD_TO_LE_NEG:
case R_NEG_TLS:
return Out::TlsPhdr->p_memsz - Sym.getVA(A);
case R_SIZE:
return Sym.getSize() + A;
case R_TLSDESC:
- return InX::Got->getGlobalDynAddr(Sym) + A;
- case R_TLSDESC_PAGE:
- return getAArch64Page(InX::Got->getGlobalDynAddr(Sym) + A) -
+ return In.Got->getGlobalDynAddr(Sym) + A;
+ case R_AARCH64_TLSDESC_PAGE:
+ return getAArch64Page(In.Got->getGlobalDynAddr(Sym) + A) -
getAArch64Page(P);
case R_TLSGD_GOT:
- return InX::Got->getGlobalDynOffset(Sym) + A;
+ return In.Got->getGlobalDynOffset(Sym) + A;
case R_TLSGD_GOT_FROM_END:
- return InX::Got->getGlobalDynOffset(Sym) + A - InX::Got->getSize();
+ return In.Got->getGlobalDynOffset(Sym) + A - In.Got->getSize();
case R_TLSGD_PC:
- return InX::Got->getGlobalDynAddr(Sym) + A - P;
+ return In.Got->getGlobalDynAddr(Sym) + A - P;
case R_TLSLD_GOT_FROM_END:
- return InX::Got->getTlsIndexOff() + A - InX::Got->getSize();
+ return In.Got->getTlsIndexOff() + A - In.Got->getSize();
case R_TLSLD_GOT:
- return InX::Got->getTlsIndexOff() + A;
+ return In.Got->getTlsIndexOff() + A;
case R_TLSLD_PC:
- return InX::Got->getTlsIndexVA() + A - P;
+ return In.Got->getTlsIndexVA() + A - P;
+ default:
+ llvm_unreachable("invalid expression");
}
- llvm_unreachable("Invalid expression");
}
// This function applies relocations to sections without SHF_ALLOC bit.
@@ -808,10 +901,10 @@ void InputSectionBase::relocateAlloc(uint8_t *Buf, uint8_t *BufEnd) {
case R_RELAX_TLS_GD_TO_LE_NEG:
Target->relaxTlsGdToLe(BufLoc, Type, TargetVA);
break;
+ case R_AARCH64_RELAX_TLS_GD_TO_IE_PAGE_PC:
case R_RELAX_TLS_GD_TO_IE:
case R_RELAX_TLS_GD_TO_IE_ABS:
case R_RELAX_TLS_GD_TO_IE_GOT_OFF:
- case R_RELAX_TLS_GD_TO_IE_PAGE_PC:
case R_RELAX_TLS_GD_TO_IE_END:
Target->relaxTlsGdToIe(BufLoc, Type, TargetVA);
break;
@@ -848,16 +941,20 @@ static void switchMorestackCallsToMorestackNonSplit(
// __morestack inside that function should be switched to
// __morestack_non_split.
Symbol *MoreStackNonSplit = Symtab->find("__morestack_non_split");
+ if (!MoreStackNonSplit) {
+ error("Mixing split-stack objects requires a definition of "
+ "__morestack_non_split");
+ return;
+ }
// Sort both collections to compare addresses efficiently.
- llvm::sort(MorestackCalls.begin(), MorestackCalls.end(),
- [](const Relocation *L, const Relocation *R) {
- return L->Offset < R->Offset;
- });
+ llvm::sort(MorestackCalls, [](const Relocation *L, const Relocation *R) {
+ return L->Offset < R->Offset;
+ });
std::vector<Defined *> Functions(Prologues.begin(), Prologues.end());
- llvm::sort(
- Functions.begin(), Functions.end(),
- [](const Defined *L, const Defined *R) { return L->Value < R->Value; });
+ llvm::sort(Functions, [](const Defined *L, const Defined *R) {
+ return L->Value < R->Value;
+ });
auto It = MorestackCalls.begin();
for (Defined *F : Functions) {
@@ -872,8 +969,8 @@ static void switchMorestackCallsToMorestackNonSplit(
}
}
-static bool enclosingPrologueAdjusted(uint64_t Offset,
- const DenseSet<Defined *> &Prologues) {
+static bool enclosingPrologueAttempted(uint64_t Offset,
+ const DenseSet<Defined *> &Prologues) {
for (Defined *F : Prologues)
if (F->Value <= Offset && Offset < F->Value + F->Size)
return true;
@@ -889,7 +986,7 @@ void InputSectionBase::adjustSplitStackFunctionPrologues(uint8_t *Buf,
uint8_t *End) {
if (!getFile<ELFT>()->SplitStack)
return;
- DenseSet<Defined *> AdjustedPrologues;
+ DenseSet<Defined *> Prologues;
std::vector<Relocation *> MorestackCalls;
for (Relocation &Rel : Relocations) {
@@ -898,15 +995,9 @@ void InputSectionBase::adjustSplitStackFunctionPrologues(uint8_t *Buf,
if (Rel.Sym->isLocal())
continue;
- Defined *D = dyn_cast<Defined>(Rel.Sym);
- // A reference to an undefined symbol was an error, and should not
- // have gotten to this point.
- if (!D)
- continue;
-
// Ignore calls into the split-stack api.
- if (D->getName().startswith("__morestack")) {
- if (D->getName().equals("__morestack"))
+ if (Rel.Sym->getName().startswith("__morestack")) {
+ if (Rel.Sym->getName().equals("__morestack"))
MorestackCalls.push_back(&Rel);
continue;
}
@@ -914,24 +1005,36 @@ void InputSectionBase::adjustSplitStackFunctionPrologues(uint8_t *Buf,
// A relocation to non-function isn't relevant. Sometimes
// __morestack is not marked as a function, so this check comes
// after the name check.
- if (D->Type != STT_FUNC)
+ if (Rel.Sym->Type != STT_FUNC)
continue;
- if (enclosingPrologueAdjusted(Rel.Offset, AdjustedPrologues))
+ // If the callee's-file was compiled with split stack, nothing to do. In
+ // this context, a "Defined" symbol is one "defined by the binary currently
+ // being produced". So an "undefined" symbol might be provided by a shared
+ // library. It is not possible to tell how such symbols were compiled, so be
+ // conservative.
+ if (Defined *D = dyn_cast<Defined>(Rel.Sym))
+ if (InputSection *IS = cast_or_null<InputSection>(D->Section))
+ if (!IS || !IS->getFile<ELFT>() || IS->getFile<ELFT>()->SplitStack)
+ continue;
+
+ if (enclosingPrologueAttempted(Rel.Offset, Prologues))
continue;
if (Defined *F = getEnclosingFunction<ELFT>(Rel.Offset)) {
- if (Target->adjustPrologueForCrossSplitStack(Buf + F->Value, End)) {
- AdjustedPrologues.insert(F);
+ Prologues.insert(F);
+ if (Target->adjustPrologueForCrossSplitStack(Buf + getOffset(F->Value),
+ End, F->StOther))
continue;
- }
+ if (!getFile<ELFT>()->SomeNoSplitStack)
+ error(lld::toString(this) + ": " + F->getName() +
+ " (with -fsplit-stack) calls " + Rel.Sym->getName() +
+ " (without -fsplit-stack), but couldn't adjust its prologue");
}
- if (!getFile<ELFT>()->SomeNoSplitStack)
- error("function call at " + getErrorLocation(Buf + Rel.Offset) +
- "crosses a split-stack boundary, but unable " +
- "to adjust the enclosing function's prologue");
}
- switchMorestackCallsToMorestackNonSplit(AdjustedPrologues, MorestackCalls);
+
+ if (Target->NeedsMoreStackNonSplit)
+ switchMorestackCallsToMorestackNonSplit(Prologues, MorestackCalls);
}
template <class ELFT> void InputSection::writeTo(uint8_t *Buf) {
@@ -960,10 +1063,23 @@ template <class ELFT> void InputSection::writeTo(uint8_t *Buf) {
return;
}
+ // If this is a compressed section, uncompress section contents directly
+ // to the buffer.
+ if (UncompressedSize >= 0 && !UncompressedBuf) {
+ size_t Size = UncompressedSize;
+ if (Error E = zlib::uncompress(toStringRef(RawData),
+ (char *)(Buf + OutSecOff), Size))
+ fatal(toString(this) +
+ ": uncompress failed: " + llvm::toString(std::move(E)));
+ uint8_t *BufEnd = Buf + OutSecOff + Size;
+ relocate<ELFT>(Buf, BufEnd);
+ return;
+ }
+
// Copy section contents from source object file to output file
// and then apply relocations.
- memcpy(Buf + OutSecOff, Data.data(), Data.size());
- uint8_t *BufEnd = Buf + OutSecOff + Data.size();
+ memcpy(Buf + OutSecOff, data().data(), data().size());
+ uint8_t *BufEnd = Buf + OutSecOff + data().size();
relocate<ELFT>(Buf, BufEnd);
}
@@ -1014,7 +1130,7 @@ template <class ELFT> void EhInputSection::split() {
template <class ELFT, class RelTy>
void EhInputSection::split(ArrayRef<RelTy> Rels) {
unsigned RelI = 0;
- for (size_t Off = 0, End = Data.size(); Off != End;) {
+ for (size_t Off = 0, End = data().size(); Off != End;) {
size_t Size = readEhRecordSize(this, Off);
Pieces.emplace_back(Off, this, Size, getReloc(Off, Size, Rels, RelI));
// The empty record is the end marker.
@@ -1094,65 +1210,32 @@ void MergeInputSection::splitIntoPieces() {
assert(Pieces.empty());
if (Flags & SHF_STRINGS)
- splitStrings(Data, Entsize);
+ splitStrings(data(), Entsize);
else
- splitNonStrings(Data, Entsize);
-
- OffsetMap.reserve(Pieces.size());
- for (size_t I = 0, E = Pieces.size(); I != E; ++I)
- OffsetMap[Pieces[I].InputOff] = I;
-}
-
-template <class It, class T, class Compare>
-static It fastUpperBound(It First, It Last, const T &Value, Compare Comp) {
- size_t Size = std::distance(First, Last);
- assert(Size != 0);
- while (Size != 1) {
- size_t H = Size / 2;
- const It MI = First + H;
- Size -= H;
- First = Comp(Value, *MI) ? First : First + H;
- }
- return Comp(Value, *First) ? First : First + 1;
-}
-
-// Do binary search to get a section piece at a given input offset.
-static SectionPiece *findSectionPiece(MergeInputSection *Sec, uint64_t Offset) {
- if (Sec->Data.size() <= Offset)
- fatal(toString(Sec) + ": entry is past the end of the section");
-
- // Find the element this offset points to.
- auto I = fastUpperBound(
- Sec->Pieces.begin(), Sec->Pieces.end(), Offset,
- [](const uint64_t &A, const SectionPiece &B) { return A < B.InputOff; });
- --I;
- return &*I;
+ splitNonStrings(data(), Entsize);
}
SectionPiece *MergeInputSection::getSectionPiece(uint64_t Offset) {
- // Find a piece starting at a given offset.
- auto It = OffsetMap.find(Offset);
- if (It != OffsetMap.end())
- return &Pieces[It->second];
+ if (this->data().size() <= Offset)
+ fatal(toString(this) + ": offset is outside the section");
// If Offset is not at beginning of a section piece, it is not in the map.
- // In that case we need to search from the original section piece vector.
- return findSectionPiece(this, Offset);
+ // In that case we need to do a binary search of the original section piece vector.
+ auto It2 =
+ llvm::upper_bound(Pieces, Offset, [](uint64_t Offset, SectionPiece P) {
+ return Offset < P.InputOff;
+ });
+ return &It2[-1];
}
// Returns the offset in an output section for a given input offset.
// Because contents of a mergeable section is not contiguous in output,
// it is not just an addition to a base output offset.
uint64_t MergeInputSection::getParentOffset(uint64_t Offset) const {
- // Find a string starting at a given offset.
- auto It = OffsetMap.find(Offset);
- if (It != OffsetMap.end())
- return Pieces[It->second].OutputOff;
-
// If Offset is not at beginning of a section piece, it is not in the map.
// In that case we need to search from the original section piece vector.
const SectionPiece &Piece =
- *findSectionPiece(const_cast<MergeInputSection *>(this), Offset);
+ *(const_cast<MergeInputSection *>(this)->getSectionPiece (Offset));
uint64_t Addend = Offset - Piece.InputOff;
return Piece.OutputOff + Addend;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-11-04 12:57:32 +0000