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//===-- SystemZMCObjectWriter.cpp - SystemZ ELF writer --------------------===//
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// The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//===----------------------------------------------------------------------===//
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#include "MCTargetDesc/SystemZMCTargetDesc.h"
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#include "MCTargetDesc/SystemZMCFixups.h"
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#include "llvm/MC/MCELFObjectWriter.h"
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#include "llvm/MC/MCExpr.h"
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#include "llvm/MC/MCValue.h"
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class SystemZObjectWriter : public MCELFObjectTargetWriter {
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SystemZObjectWriter(uint8_t OSABI);
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virtual ~SystemZObjectWriter();
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// Override MCELFObjectTargetWriter.
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virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
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bool IsPCRel, bool IsRelocWithSymbol,
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int64_t Addend) const LLVM_OVERRIDE;
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virtual const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
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const MCValue &Target,
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bool IsPCRel) const LLVM_OVERRIDE;
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} // end anonymouse namespace
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SystemZObjectWriter::SystemZObjectWriter(uint8_t OSABI)
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: MCELFObjectTargetWriter(/*Is64Bit=*/true, OSABI, ELF::EM_S390,
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/*HasRelocationAddend=*/ true) {}
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SystemZObjectWriter::~SystemZObjectWriter() {
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// Return the relocation type for an absolute value of MCFixupKind Kind.
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static unsigned getAbsoluteReloc(unsigned Kind) {
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case FK_Data_1: return ELF::R_390_8;
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case FK_Data_2: return ELF::R_390_16;
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case FK_Data_4: return ELF::R_390_32;
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case FK_Data_8: return ELF::R_390_64;
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llvm_unreachable("Unsupported absolute address");
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// Return the relocation type for a PC-relative value of MCFixupKind Kind.
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static unsigned getPCRelReloc(unsigned Kind) {
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case FK_Data_2: return ELF::R_390_PC16;
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case FK_Data_4: return ELF::R_390_PC32;
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case FK_Data_8: return ELF::R_390_PC64;
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case SystemZ::FK_390_PC16DBL: return ELF::R_390_PC16DBL;
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case SystemZ::FK_390_PC32DBL: return ELF::R_390_PC32DBL;
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case SystemZ::FK_390_PLT16DBL: return ELF::R_390_PLT16DBL;
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case SystemZ::FK_390_PLT32DBL: return ELF::R_390_PLT32DBL;
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llvm_unreachable("Unsupported PC-relative address");
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// Return the R_390_TLS_LE* relocation type for MCFixupKind Kind.
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static unsigned getTLSLEReloc(unsigned Kind) {
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case FK_Data_4: return ELF::R_390_TLS_LE32;
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case FK_Data_8: return ELF::R_390_TLS_LE64;
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llvm_unreachable("Unsupported absolute address");
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// Return the PLT relocation counterpart of MCFixupKind Kind.
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static unsigned getPLTReloc(unsigned Kind) {
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case SystemZ::FK_390_PC16DBL: return ELF::R_390_PLT16DBL;
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case SystemZ::FK_390_PC32DBL: return ELF::R_390_PLT32DBL;
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llvm_unreachable("Unsupported absolute address");
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unsigned SystemZObjectWriter::GetRelocType(const MCValue &Target,
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bool IsRelocWithSymbol,
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int64_t Addend) const {
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MCSymbolRefExpr::VariantKind Modifier = (Target.isAbsolute() ?
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MCSymbolRefExpr::VK_None :
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Target.getSymA()->getKind());
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unsigned Kind = Fixup.getKind();
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case MCSymbolRefExpr::VK_None:
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return getPCRelReloc(Kind);
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return getAbsoluteReloc(Kind);
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case MCSymbolRefExpr::VK_NTPOFF:
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assert(!IsPCRel && "NTPOFF shouldn't be PC-relative");
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return getTLSLEReloc(Kind);
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case MCSymbolRefExpr::VK_GOT:
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if (IsPCRel && Kind == SystemZ::FK_390_PC32DBL)
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return ELF::R_390_GOTENT;
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llvm_unreachable("Only PC-relative GOT accesses are supported for now");
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case MCSymbolRefExpr::VK_PLT:
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assert(IsPCRel && "@PLT shouldt be PC-relative");
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return getPLTReloc(Kind);
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llvm_unreachable("Modifier not supported");
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const MCSymbol *SystemZObjectWriter::ExplicitRelSym(const MCAssembler &Asm,
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const MCValue &Target,
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const MCFixup &Fixup,
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bool IsPCRel) const {
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// The addend in a PC-relative R_390_* relocation is always applied to
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// the PC-relative part of the address. If some kind of indirection
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// is applied to the symbol first, we can't use an addend there too.
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if (!Target.isAbsolute() &&
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Target.getSymA()->getKind() != MCSymbolRefExpr::VK_None &&
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return &Target.getSymA()->getSymbol().AliasedSymbol();
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MCObjectWriter *llvm::createSystemZObjectWriter(raw_ostream &OS,
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MCELFObjectTargetWriter *MOTW = new SystemZObjectWriter(OSABI);
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return createELFObjectWriter(MOTW, OS, /*IsLittleEndian=*/false);