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-rw-r--r--lld/ELF/OutputSections.cpp22
-rw-r--r--lld/ELF/OutputSections.h3
-rw-r--r--lld/ELF/Target.cpp107
-rw-r--r--lld/ELF/Target.h5
4 files changed, 101 insertions, 36 deletions
diff --git a/lld/ELF/OutputSections.cpp b/lld/ELF/OutputSections.cpp
index 6563b1a61ca..0006ccf3c08 100644
--- a/lld/ELF/OutputSections.cpp
+++ b/lld/ELF/OutputSections.cpp
@@ -150,18 +150,25 @@ template <class ELFT> void PltSection<ELFT>::writeTo(uint8_t *Buf) {
Target->writePltZeroEntry(Buf, Out<ELFT>::GotPlt->getVA(), this->getVA());
Off += Target->getPltZeroEntrySize();
}
- for (const SymbolBody *E : Entries) {
- uint64_t Got = LazyReloc ? Out<ELFT>::GotPlt->getEntryAddr(*E)
- : Out<ELFT>::Got->getEntryAddr(*E);
+ for (std::pair<const SymbolBody *, unsigned> &I : Entries) {
+ const SymbolBody *E = I.first;
+ unsigned RelOff = I.second;
+ uint64_t GotVA =
+ LazyReloc ? Out<ELFT>::GotPlt->getVA() : Out<ELFT>::Got->getVA();
+ uint64_t GotE = LazyReloc ? Out<ELFT>::GotPlt->getEntryAddr(*E)
+ : Out<ELFT>::Got->getEntryAddr(*E);
uint64_t Plt = this->getVA() + Off;
- Target->writePltEntry(Buf + Off, Got, Plt, E->PltIndex);
+ Target->writePltEntry(Buf + Off, GotVA, GotE, Plt, E->PltIndex, RelOff);
Off += Target->getPltEntrySize();
}
}
template <class ELFT> void PltSection<ELFT>::addEntry(SymbolBody *Sym) {
Sym->PltIndex = Entries.size();
- Entries.push_back(Sym);
+ unsigned RelOff = Target->supportsLazyRelocations()
+ ? Out<ELFT>::RelaPlt->getRelocOffset()
+ : Out<ELFT>::RelaDyn->getRelocOffset();
+ Entries.push_back(std::make_pair(Sym, RelOff));
}
template <class ELFT>
@@ -281,6 +288,11 @@ template <class ELFT> void RelocationSection<ELFT>::writeTo(uint8_t *Buf) {
}
}
+template <class ELFT> unsigned RelocationSection<ELFT>::getRelocOffset() {
+ const unsigned EntrySize = IsRela ? sizeof(Elf_Rela) : sizeof(Elf_Rel);
+ return EntrySize * Relocs.size();
+}
+
template <class ELFT> void RelocationSection<ELFT>::finalize() {
this->Header.sh_link = Out<ELFT>::DynSymTab->SectionIndex;
this->Header.sh_size = Relocs.size() * this->Header.sh_entsize;
diff --git a/lld/ELF/OutputSections.h b/lld/ELF/OutputSections.h
index f3266f5640d..27e6b68ab72 100644
--- a/lld/ELF/OutputSections.h
+++ b/lld/ELF/OutputSections.h
@@ -166,7 +166,7 @@ public:
uintX_t getEntryAddr(const SymbolBody &B) const;
private:
- std::vector<const SymbolBody *> Entries;
+ std::vector<std::pair<const SymbolBody *, unsigned>> Entries;
};
template <class ELFT> struct DynamicReloc {
@@ -216,6 +216,7 @@ class RelocationSection final : public OutputSectionBase<ELFT> {
public:
RelocationSection(StringRef Name, bool IsRela);
void addReloc(const DynamicReloc<ELFT> &Reloc) { Relocs.push_back(Reloc); }
+ unsigned getRelocOffset();
void finalize() override;
void writeTo(uint8_t *Buf) override;
bool hasRelocs() const { return !Relocs.empty(); }
diff --git a/lld/ELF/Target.cpp b/lld/ELF/Target.cpp
index 78e5df6561b..bad344b0bc3 100644
--- a/lld/ELF/Target.cpp
+++ b/lld/ELF/Target.cpp
@@ -46,13 +46,15 @@ namespace {
class X86TargetInfo final : public TargetInfo {
public:
X86TargetInfo();
+ void writeGotPltHeaderEntries(uint8_t *Buf) const override;
unsigned getDynReloc(unsigned Type) const override;
bool isTlsDynReloc(unsigned Type) const override;
void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const override;
void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
uint64_t PltEntryAddr) const override;
- void writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr, int32_t Index) const override;
+ void writePltEntry(uint8_t *Buf, uint64_t GotAddr, uint64_t GotEntryAddr,
+ uint64_t PltEntryAddr, int32_t Index,
+ unsigned RelOff) const override;
bool relocNeedsCopy(uint32_t Type, const SymbolBody &S) const override;
bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const override;
bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const override;
@@ -69,8 +71,9 @@ public:
void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const override;
void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
uint64_t PltEntryAddr) const override;
- void writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr, int32_t Index) const override;
+ void writePltEntry(uint8_t *Buf, uint64_t GotAddr, uint64_t GotEntryAddr,
+ uint64_t PltEntryAddr, int32_t Index,
+ unsigned RelOff) const override;
bool relocNeedsCopy(uint32_t Type, const SymbolBody &S) const override;
bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const override;
bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const override;
@@ -96,8 +99,9 @@ public:
void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const override;
void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
uint64_t PltEntryAddr) const override;
- void writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr, int32_t Index) const override;
+ void writePltEntry(uint8_t *Buf, uint64_t GotAddr, uint64_t GotEntryAddr,
+ uint64_t PltEntryAddr, int32_t Index,
+ unsigned RelOff) const override;
bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const override;
bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const override;
void relocateOne(uint8_t *Loc, uint8_t *BufEnd, uint32_t Type, uint64_t P,
@@ -113,8 +117,9 @@ public:
void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const override;
void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
uint64_t PltEntryAddr) const override;
- void writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr, int32_t Index) const override;
+ void writePltEntry(uint8_t *Buf, uint64_t GotAddr, uint64_t GotEntryAddr,
+ uint64_t PltEntryAddr, int32_t Index,
+ unsigned RelOff) const override;
bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const override;
bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const override;
void relocateOne(uint8_t *Loc, uint8_t *BufEnd, uint32_t Type, uint64_t P,
@@ -129,8 +134,9 @@ public:
void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const override;
void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
uint64_t PltEntryAddr) const override;
- void writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr, int32_t Index) const override;
+ void writePltEntry(uint8_t *Buf, uint64_t GotAddr, uint64_t GotEntryAddr,
+ uint64_t PltEntryAddr, int32_t Index,
+ unsigned RelOff) const override;
bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const override;
bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const override;
void relocateOne(uint8_t *Loc, uint8_t *BufEnd, uint32_t Type, uint64_t P,
@@ -195,6 +201,18 @@ X86TargetInfo::X86TargetInfo() {
GotReloc = R_386_GLOB_DAT;
GotRefReloc = R_386_GOT32;
PltReloc = R_386_JUMP_SLOT;
+ LazyRelocations = true;
+ PltEntrySize = 16;
+ PltZeroEntrySize = 16;
+}
+
+void X86TargetInfo::writeGotPltHeaderEntries(uint8_t *Buf) const {
+ write32le(Buf, Out<ELF32LE>::Dynamic->getVA());
+}
+
+void X86TargetInfo::writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const {
+ // Skip 6 bytes of "pushl (GOT+4)"
+ write32le(Buf, Plt + 6);
}
unsigned X86TargetInfo::getDynReloc(unsigned Type) const {
@@ -211,17 +229,44 @@ bool X86TargetInfo::isTlsDynReloc(unsigned Type) const {
return false;
}
-void X86TargetInfo::writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const {}
void X86TargetInfo::writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr) const {}
+ uint64_t PltEntryAddr) const {
+ // Executable files and shared object files have
+ // separate procedure linkage tables.
+ if (Config->Shared) {
+ const uint8_t V[] = {
+ 0xff, 0xb3, 0x04, 0x00, 0x00, 0x00, // pushl 4(%ebx
+ 0xff, 0xa3, 0x08, 0x00, 0x00, 0x00, // jmp *8(%ebx)
+ 0x90, 0x90, 0x90, 0x90 // nop;nop;nop;nop
+ };
+ memcpy(Buf, V, sizeof(V));
+ return;
+ }
-void X86TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr, int32_t Index) const {
- // jmpl *val; nop; nop
- const uint8_t Inst[] = {0xff, 0x25, 0, 0, 0, 0, 0x90, 0x90};
+ const uint8_t PltData[] = {
+ 0xff, 0x35, 0x00, 0x00, 0x00, 0x00, // pushl (GOT+4)
+ 0xff, 0x25, 0x00, 0x00, 0x00, 0x00, // jmp *(GOT+8)
+ 0x90, 0x90, 0x90, 0x90 // nop;nop;nop;nop
+ };
+ memcpy(Buf, PltData, sizeof(PltData));
+ write32le(Buf + 2, GotEntryAddr + 4); // GOT+4
+ write32le(Buf + 8, GotEntryAddr + 8); // GOT+8
+}
+
+void X86TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotAddr,
+ uint64_t GotEntryAddr, uint64_t PltEntryAddr,
+ int32_t Index, unsigned RelOff) const {
+ const uint8_t Inst[] = {
+ 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, // jmp *foo_in_GOT|*foo@GOT(%ebx)
+ 0x68, 0x00, 0x00, 0x00, 0x00, // pushl $reloc_offset
+ 0xe9, 0x00, 0x00, 0x00, 0x00 // jmp .PLT0@PC
+ };
memcpy(Buf, Inst, sizeof(Inst));
- assert(isUInt<32>(GotEntryAddr));
- write32le(Buf + 2, GotEntryAddr);
+ // jmp *foo@GOT(%ebx) or jmp *foo_in_GOT
+ Buf[1] = Config->Shared ? 0xa3 : 0x25;
+ write32le(Buf + 2, Config->Shared ? (GotEntryAddr - GotAddr) : GotEntryAddr);
+ write32le(Buf + 7, RelOff);
+ write32le(Buf + 12, -Index * PltEntrySize - PltZeroEntrySize - 16);
}
bool X86TargetInfo::relocNeedsCopy(uint32_t Type, const SymbolBody &S) const {
@@ -303,9 +348,10 @@ void X86_64TargetInfo::writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
write32le(Buf + 8, GotEntryAddr - PltEntryAddr + 4); // GOT+16
}
-void X86_64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr,
- int32_t Index) const {
+void X86_64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotAddr,
+ uint64_t GotEntryAddr,
+ uint64_t PltEntryAddr, int32_t Index,
+ unsigned RelOff) const {
const uint8_t Inst[] = {
0xff, 0x25, 0x00, 0x00, 0x00, 0x00, // jmpq *got(%rip)
0x68, 0x00, 0x00, 0x00, 0x00, // pushq <relocation index>
@@ -604,8 +650,10 @@ uint64_t getPPC64TocBase() {
void PPC64TargetInfo::writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const {}
void PPC64TargetInfo::writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
uint64_t PltEntryAddr) const {}
-void PPC64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr, int32_t Index) const {
+void PPC64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotAddr,
+ uint64_t GotEntryAddr,
+ uint64_t PltEntryAddr, int32_t Index,
+ unsigned RelOff) const {
uint64_t Off = GotEntryAddr - getPPC64TocBase();
// FIXME: What we should do, in theory, is get the offset of the function
@@ -816,9 +864,10 @@ void AArch64TargetInfo::writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
GotEntryAddr + 16);
}
-void AArch64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr,
- int32_t Index) const {
+void AArch64TargetInfo::writePltEntry(uint8_t *Buf, uint64_t GotAddr,
+ uint64_t GotEntryAddr,
+ uint64_t PltEntryAddr, int32_t Index,
+ unsigned RelOff) const {
const uint8_t Inst[] = {
0x10, 0x00, 0x00, 0x90, // adrp x16, Page(&(.plt.got[n]))
0x11, 0x02, 0x40, 0xf9, // ldr x17, [x16, Offset(&(.plt.got[n]))]
@@ -977,8 +1026,10 @@ template <class ELFT>
void MipsTargetInfo<ELFT>::writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
uint64_t PltEntryAddr) const {}
template <class ELFT>
-void MipsTargetInfo<ELFT>::writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr, int32_t Index) const {}
+void MipsTargetInfo<ELFT>::writePltEntry(uint8_t *Buf, uint64_t GotAddr,
+ uint64_t GotEntryAddr,
+ uint64_t PltEntryAddr, int32_t Index,
+ unsigned RelOff) const {}
template <class ELFT>
bool MipsTargetInfo<ELFT>::relocNeedsGot(uint32_t Type,
diff --git a/lld/ELF/Target.h b/lld/ELF/Target.h
index d8132316bf8..939223414ec 100644
--- a/lld/ELF/Target.h
+++ b/lld/ELF/Target.h
@@ -50,8 +50,9 @@ public:
virtual void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const = 0;
virtual void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
uint64_t PltEntryAddr) const = 0;
- virtual void writePltEntry(uint8_t *Buf, uint64_t GotEntryAddr,
- uint64_t PltEntryAddr, int32_t Index) const = 0;
+ virtual void writePltEntry(uint8_t *Buf, uint64_t GotAddr,
+ uint64_t GotEntryAddr, uint64_t PltEntryAddr,
+ int32_t Index, unsigned RelOff) const = 0;
virtual bool isRelRelative(uint32_t Type) const;
virtual bool relocNeedsCopy(uint32_t Type, const SymbolBody &S) const;
virtual bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const = 0;
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