diff options
Diffstat (limited to 'lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp')
-rw-r--r-- | lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp | 104 |
1 files changed, 13 insertions, 91 deletions
diff --git a/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp b/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp index 44c5731282..a4661b1a4f 100644 --- a/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp +++ b/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp @@ -36,10 +36,8 @@ namespace { unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup, bool IsPCRel) const override; - const MCSymbol *ExplicitRelSym(const MCAssembler &Asm, - const MCValue &Target, const MCFragment &F, - const MCFixup &Fixup, - bool IsPCRel) const override; + + bool needsRelocateWithSymbol(unsigned Type) const override; }; } @@ -50,90 +48,18 @@ ARMELFObjectWriter::ARMELFObjectWriter(uint8_t OSABI) ARMELFObjectWriter::~ARMELFObjectWriter() {} -// In ARM, _MergedGlobals and other most symbols get emitted directly. -// I.e. not as an offset to a section symbol. -// This code is an approximation of what ARM/gcc does. - -STATISTIC(PCRelCount, "Total number of PIC Relocations"); -STATISTIC(NonPCRelCount, "Total number of non-PIC relocations"); - -const MCSymbol *ARMELFObjectWriter::ExplicitRelSym(const MCAssembler &Asm, - const MCValue &Target, - const MCFragment &F, - const MCFixup &Fixup, - bool IsPCRel) const { - const MCSymbol &Symbol = Target.getSymA()->getSymbol().AliasedSymbol(); - bool EmitThisSym = false; - - const MCSectionELF &Section = - static_cast<const MCSectionELF&>(Symbol.getSection()); - bool InNormalSection = true; - unsigned RelocType = 0; - RelocType = GetRelocTypeInner(Target, Fixup, IsPCRel); - assert(!Target.getSymB() || - Target.getSymB()->getKind() == MCSymbolRefExpr::VK_None); - - DEBUG( - MCSymbolRefExpr::VariantKind Kind = Fixup.getAccessVariant(); - dbgs() << "considering symbol " - << Section.getSectionName() << "/" - << Symbol.getName() << "/" - << " Rel:" << (unsigned)RelocType - << " Kind: " << (int)Kind - << " Tmp:" - << Symbol.isAbsolute() << "/" << Symbol.isDefined() << "/" - << Symbol.isVariable() << "/" << Symbol.isTemporary() - << " Counts:" << PCRelCount << "/" << NonPCRelCount << "\n"); - - if (IsPCRel) { ++PCRelCount; - switch (RelocType) { - default: - // Most relocation types are emitted as explicit symbols - InNormalSection = - StringSwitch<bool>(Section.getSectionName()) - .Case(".data.rel.ro.local", false) - .Case(".data.rel", false) - .Case(".bss", false) - .Default(true); - EmitThisSym = true; - break; - case ELF::R_ARM_ABS32: - // But things get strange with R_ARM_ABS32 - // In this case, most things that go in .rodata show up - // as section relative relocations - InNormalSection = - StringSwitch<bool>(Section.getSectionName()) - .Case(".data.rel.ro.local", false) - .Case(".data.rel", false) - .Case(".rodata", false) - .Case(".bss", false) - .Default(true); - EmitThisSym = false; - break; - } - } else { - NonPCRelCount++; - InNormalSection = - StringSwitch<bool>(Section.getSectionName()) - .Case(".data.rel.ro.local", false) - .Case(".rodata", false) - .Case(".data.rel", false) - .Case(".bss", false) - .Default(true); - - switch (RelocType) { - default: EmitThisSym = true; break; - case ELF::R_ARM_ABS32: EmitThisSym = false; break; - case ELF::R_ARM_PREL31: EmitThisSym = false; break; - } - } - - if (EmitThisSym) - return &Symbol; - if (! Symbol.isTemporary() && InNormalSection) { - return &Symbol; +bool ARMELFObjectWriter::needsRelocateWithSymbol(unsigned Type) const { + // FIXME: This is extremelly conservative. This really needs to use a + // whitelist with a clear explanation for why each realocation needs to + // point to the symbol, not to the section. + switch (Type) { + default: + return true; + + case ELF::R_ARM_PREL31: + case ELF::R_ARM_ABS32: + return false; } - return NULL; } // Need to examine the Fixup when determining whether to @@ -191,19 +117,15 @@ unsigned ARMELFObjectWriter::GetRelocTypeInner(const MCValue &Target, Type = ELF::R_ARM_THM_JUMP24; break; case ARM::fixup_arm_movt_hi16: - case ARM::fixup_arm_movt_hi16_pcrel: Type = ELF::R_ARM_MOVT_PREL; break; case ARM::fixup_arm_movw_lo16: - case ARM::fixup_arm_movw_lo16_pcrel: Type = ELF::R_ARM_MOVW_PREL_NC; break; case ARM::fixup_t2_movt_hi16: - case ARM::fixup_t2_movt_hi16_pcrel: Type = ELF::R_ARM_THM_MOVT_PREL; break; case ARM::fixup_t2_movw_lo16: - case ARM::fixup_t2_movw_lo16_pcrel: Type = ELF::R_ARM_THM_MOVW_PREL_NC; break; case ARM::fixup_arm_thumb_bl: |