diff options
| -rw-r--r-- | lib/MC/ELFObjectWriter.cpp | 71 | ||||
| -rw-r--r-- | test/MC/ELF/alias-reloc.s | 24 |
2 files changed, 61 insertions, 34 deletions
diff --git a/lib/MC/ELFObjectWriter.cpp b/lib/MC/ELFObjectWriter.cpp index cd7eb1c..3346930 100644 --- a/lib/MC/ELFObjectWriter.cpp +++ b/lib/MC/ELFObjectWriter.cpp @@ -180,6 +180,11 @@ namespace { unsigned ShstrtabIndex; + + const MCSymbol *SymbolToReloc(const MCAssembler &Asm, + const MCValue &Target, + const MCFragment &F) const; + public: ELFObjectWriter(raw_ostream &_OS, bool _Is64Bit, bool IsLittleEndian, uint16_t _EMachine, bool _HasRelAddend, @@ -624,36 +629,53 @@ void ELFObjectWriter::WriteSymbolTable(MCDataFragment *SymtabF, } } -static bool ShouldRelocOnSymbol(const MCSymbolData &SD, - const MCValue &Target, - const MCFragment &F) { - const MCSymbol &Symbol = SD.getSymbol(); +const MCSymbol *ELFObjectWriter::SymbolToReloc(const MCAssembler &Asm, + const MCValue &Target, + const MCFragment &F) const { + const MCSymbol &Symbol = Target.getSymA()->getSymbol(); + const MCSymbol &ASymbol = AliasedSymbol(Symbol); + const MCSymbol *RenamedP = Renames.lookup(&Symbol); + + if (!RenamedP) { + if (Target.getSymA()->getKind() == MCSymbolRefExpr::VK_None || + Asm.getSymbolData(Symbol).getFlags() & ELF_Other_Weakref) + RenamedP = &ASymbol; + else + RenamedP = &Symbol; + } + const MCSymbol &Renamed = *RenamedP; + + MCSymbolData &SD = Asm.getSymbolData(Symbol); + if (Symbol.isUndefined()) - return true; + return &Renamed; + + if (SD.isExternal()) + return &Renamed; const MCSectionELF &Section = static_cast<const MCSectionELF&>(Symbol.getSection()); - if (SD.isExternal()) - return true; + if (Section.getKind().isBSS()) + return NULL; MCSymbolRefExpr::VariantKind Kind = Target.getSymA()->getKind(); const MCSectionELF &Sec2 = static_cast<const MCSectionELF&>(F.getParent()->getSection()); - if (Section.getKind().isBSS()) - return false; - if (&Sec2 != &Section && (Kind == MCSymbolRefExpr::VK_PLT || Kind == MCSymbolRefExpr::VK_GOTPCREL || Kind == MCSymbolRefExpr::VK_GOTOFF)) - return true; + return &Renamed; - if (Section.getFlags() & MCSectionELF::SHF_MERGE) - return Target.getConstant() != 0; + if (Section.getFlags() & MCSectionELF::SHF_MERGE) { + if (Target.getConstant() != 0) + return &Renamed; + return NULL; + } - return false; + return NULL; } // FIXME: this is currently X86/X86_64 only @@ -667,17 +689,10 @@ void ELFObjectWriter::RecordRelocation(const MCAssembler &Asm, int Index = 0; int64_t Value = Target.getConstant(); const MCSymbol &Symbol = Target.getSymA()->getSymbol(); - const MCSymbol &ASymbol = AliasedSymbol(Symbol); - const MCSymbol *RenamedP = Renames.lookup(&Symbol); - if (!RenamedP) - RenamedP = &ASymbol; - const MCSymbol &Renamed = *RenamedP; + const MCSymbol *RelocSymbol = SymbolToReloc(Asm, Target, *Fragment); bool IsPCRel = isFixupKindX86PCRel(Fixup.getKind()); if (!Target.isAbsolute()) { - MCSymbolData &SD = Asm.getSymbolData(Symbol); - MCFragment *F = SD.getFragment(); - if (const MCSymbolRefExpr *RefB = Target.getSymB()) { const MCSymbol &SymbolB = RefB->getSymbol(); MCSymbolData &SDB = Asm.getSymbolData(SymbolB); @@ -692,8 +707,10 @@ void ELFObjectWriter::RecordRelocation(const MCAssembler &Asm, Value += b - a; } - bool RelocOnSymbol = ShouldRelocOnSymbol(SD, Target, *Fragment); - if (!RelocOnSymbol) { + if (!RelocSymbol) { + MCSymbolData &SD = Asm.getSymbolData(Symbol); + MCFragment *F = SD.getFragment(); + Index = F->getParent()->getOrdinal(); MCSectionData *FSD = F->getParent(); @@ -701,9 +718,9 @@ void ELFObjectWriter::RecordRelocation(const MCAssembler &Asm, Value += Layout.getSymbolAddress(&SD) - Layout.getSectionAddress(FSD); } else { if (Asm.getSymbolData(Symbol).getFlags() & ELF_Other_Weakref) - WeakrefUsedInReloc.insert(&Renamed); + WeakrefUsedInReloc.insert(RelocSymbol); else - UsedInReloc.insert(&Renamed); + UsedInReloc.insert(RelocSymbol); Index = -1; } Addend = Value; @@ -851,7 +868,7 @@ void ELFObjectWriter::RecordRelocation(const MCAssembler &Asm, ERE.Index = Index; ERE.Type = Type; - ERE.Symbol = &Renamed; + ERE.Symbol = RelocSymbol; ERE.r_offset = Layout.getFragmentOffset(Fragment) + Fixup.getOffset(); diff --git a/test/MC/ELF/alias-reloc.s b/test/MC/ELF/alias-reloc.s index e31afa1..352a2a2 100644 --- a/test/MC/ELF/alias-reloc.s +++ b/test/MC/ELF/alias-reloc.s @@ -1,16 +1,26 @@ // RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o - | elf-dump | FileCheck %s -// Test that this produces a R_X86_64_PLT32. We produce a relocation with foo -// and gas with bar, but both should be OK as long as the type is correct. +// Test that this produces a R_X86_64_PLT32 with bar. + .globl foo foo: bar = foo + .section zed, "", @progbits call bar@PLT -// CHECK: # Relocation 0 -// CHECK-NEXT: (('r_offset', -// CHECK-NEXT: ('r_sym', +// CHECK: # Symbol 0x00000001 +// CHECK-NEXT: (('st_name', 0x00000005) # 'bar' +// CHECK-NEXT: ('st_bind', 0x00000000) +// CHECK-NEXT: ('st_type', 0x00000000) +// CHECK-NEXT: ('st_other', 0x00000000) +// CHECK-NEXT: ('st_shndx', 0x00000001) +// CHECK-NEXT: ('st_value', 0x00000000) +// CHECK-NEXT: ('st_size', 0x00000000) +// CHECK-NEXT: ), + +// CHECK: # Relocation 0x00000000 +// CHECK-NEXT: (('r_offset', 0x00000001) +// CHECK-NEXT: ('r_sym', 0x00000001) // CHECK-NEXT: ('r_type', 0x00000004) -// CHECK-NEXT: ('r_addend', +// CHECK-NEXT: ('r_addend', 0xfffffffc) // CHECK-NEXT: ), -// CHECK-NEXT: ]) |