| //===-- PPCELFObjectWriter.cpp - PPC ELF Writer ---------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "MCTargetDesc/PPCFixupKinds.h" |
| #include "MCTargetDesc/PPCMCExpr.h" |
| #include "MCTargetDesc/PPCMCTargetDesc.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/MC/MCELFObjectWriter.h" |
| #include "llvm/MC/MCExpr.h" |
| #include "llvm/MC/MCObjectWriter.h" |
| #include "llvm/MC/MCSymbolELF.h" |
| #include "llvm/MC/MCValue.h" |
| #include "llvm/Support/ErrorHandling.h" |
| |
| using namespace llvm; |
| |
| namespace { |
| class PPCELFObjectWriter : public MCELFObjectTargetWriter { |
| public: |
| PPCELFObjectWriter(bool Is64Bit, uint8_t OSABI); |
| |
| protected: |
| unsigned getRelocType(MCContext &Ctx, const MCValue &Target, |
| const MCFixup &Fixup, bool IsPCRel) const override; |
| |
| bool needsRelocateWithSymbol(const MCSymbol &Sym, |
| unsigned Type) const override; |
| }; |
| } |
| |
| PPCELFObjectWriter::PPCELFObjectWriter(bool Is64Bit, uint8_t OSABI) |
| : MCELFObjectTargetWriter(Is64Bit, OSABI, |
| Is64Bit ? ELF::EM_PPC64 : ELF::EM_PPC, |
| /*HasRelocationAddend*/ true) {} |
| |
| static MCSymbolRefExpr::VariantKind getAccessVariant(const MCValue &Target, |
| const MCFixup &Fixup) { |
| const MCExpr *Expr = Fixup.getValue(); |
| |
| if (Expr->getKind() != MCExpr::Target) |
| return Target.getAccessVariant(); |
| |
| switch (cast<PPCMCExpr>(Expr)->getKind()) { |
| case PPCMCExpr::VK_PPC_None: |
| return MCSymbolRefExpr::VK_None; |
| case PPCMCExpr::VK_PPC_LO: |
| return MCSymbolRefExpr::VK_PPC_LO; |
| case PPCMCExpr::VK_PPC_HI: |
| return MCSymbolRefExpr::VK_PPC_HI; |
| case PPCMCExpr::VK_PPC_HA: |
| return MCSymbolRefExpr::VK_PPC_HA; |
| case PPCMCExpr::VK_PPC_HIGH: |
| return MCSymbolRefExpr::VK_PPC_HIGH; |
| case PPCMCExpr::VK_PPC_HIGHA: |
| return MCSymbolRefExpr::VK_PPC_HIGHA; |
| case PPCMCExpr::VK_PPC_HIGHERA: |
| return MCSymbolRefExpr::VK_PPC_HIGHERA; |
| case PPCMCExpr::VK_PPC_HIGHER: |
| return MCSymbolRefExpr::VK_PPC_HIGHER; |
| case PPCMCExpr::VK_PPC_HIGHEST: |
| return MCSymbolRefExpr::VK_PPC_HIGHEST; |
| case PPCMCExpr::VK_PPC_HIGHESTA: |
| return MCSymbolRefExpr::VK_PPC_HIGHESTA; |
| } |
| llvm_unreachable("unknown PPCMCExpr kind"); |
| } |
| |
| unsigned PPCELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target, |
| const MCFixup &Fixup, |
| bool IsPCRel) const { |
| MCFixupKind Kind = Fixup.getKind(); |
| if (Kind >= FirstLiteralRelocationKind) |
| return Kind - FirstLiteralRelocationKind; |
| MCSymbolRefExpr::VariantKind Modifier = getAccessVariant(Target, Fixup); |
| |
| // determine the type of the relocation |
| unsigned Type; |
| if (IsPCRel) { |
| switch (Fixup.getTargetKind()) { |
| default: |
| llvm_unreachable("Unimplemented"); |
| case PPC::fixup_ppc_br24: |
| case PPC::fixup_ppc_br24abs: |
| case PPC::fixup_ppc_br24_notoc: |
| switch (Modifier) { |
| default: llvm_unreachable("Unsupported Modifier"); |
| case MCSymbolRefExpr::VK_None: |
| Type = ELF::R_PPC_REL24; |
| break; |
| case MCSymbolRefExpr::VK_PLT: |
| Type = ELF::R_PPC_PLTREL24; |
| break; |
| case MCSymbolRefExpr::VK_PPC_LOCAL: |
| Type = ELF::R_PPC_LOCAL24PC; |
| break; |
| case MCSymbolRefExpr::VK_PPC_NOTOC: |
| Type = ELF::R_PPC64_REL24_NOTOC; |
| break; |
| } |
| break; |
| case PPC::fixup_ppc_brcond14: |
| case PPC::fixup_ppc_brcond14abs: |
| Type = ELF::R_PPC_REL14; |
| break; |
| case PPC::fixup_ppc_half16: |
| switch (Modifier) { |
| default: llvm_unreachable("Unsupported Modifier"); |
| case MCSymbolRefExpr::VK_None: |
| Type = ELF::R_PPC_REL16; |
| break; |
| case MCSymbolRefExpr::VK_PPC_LO: |
| Type = ELF::R_PPC_REL16_LO; |
| break; |
| case MCSymbolRefExpr::VK_PPC_HI: |
| Type = ELF::R_PPC_REL16_HI; |
| break; |
| case MCSymbolRefExpr::VK_PPC_HA: |
| Type = ELF::R_PPC_REL16_HA; |
| break; |
| } |
| break; |
| case PPC::fixup_ppc_half16ds: |
| Target.print(errs()); |
| errs() << '\n'; |
| report_fatal_error("Invalid PC-relative half16ds relocation"); |
| case PPC::fixup_ppc_pcrel34: |
| switch (Modifier) { |
| default: |
| llvm_unreachable("Unsupported Modifier for fixup_ppc_pcrel34"); |
| case MCSymbolRefExpr::VK_PCREL: |
| Type = ELF::R_PPC64_PCREL34; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_PCREL: |
| Type = ELF::R_PPC64_GOT_PCREL34; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_PCREL: |
| Type = ELF::R_PPC64_GOT_TLSGD_PCREL34; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_PCREL: |
| Type = ELF::R_PPC64_GOT_TLSLD_PCREL34; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TPREL_PCREL: |
| Type = ELF::R_PPC64_GOT_TPREL_PCREL34; |
| break; |
| } |
| break; |
| case FK_Data_4: |
| case FK_PCRel_4: |
| Type = ELF::R_PPC_REL32; |
| break; |
| case FK_Data_8: |
| case FK_PCRel_8: |
| Type = ELF::R_PPC64_REL64; |
| break; |
| } |
| } else { |
| switch (Fixup.getTargetKind()) { |
| default: llvm_unreachable("invalid fixup kind!"); |
| case PPC::fixup_ppc_br24abs: |
| Type = ELF::R_PPC_ADDR24; |
| break; |
| case PPC::fixup_ppc_brcond14abs: |
| Type = ELF::R_PPC_ADDR14; // XXX: or BRNTAKEN?_ |
| break; |
| case PPC::fixup_ppc_half16: |
| switch (Modifier) { |
| default: llvm_unreachable("Unsupported Modifier"); |
| case MCSymbolRefExpr::VK_None: |
| Type = ELF::R_PPC_ADDR16; |
| break; |
| case MCSymbolRefExpr::VK_PPC_LO: |
| Type = ELF::R_PPC_ADDR16_LO; |
| break; |
| case MCSymbolRefExpr::VK_PPC_HI: |
| Type = ELF::R_PPC_ADDR16_HI; |
| break; |
| case MCSymbolRefExpr::VK_PPC_HA: |
| Type = ELF::R_PPC_ADDR16_HA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_HIGH: |
| Type = ELF::R_PPC64_ADDR16_HIGH; |
| break; |
| case MCSymbolRefExpr::VK_PPC_HIGHA: |
| Type = ELF::R_PPC64_ADDR16_HIGHA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_HIGHER: |
| Type = ELF::R_PPC64_ADDR16_HIGHER; |
| break; |
| case MCSymbolRefExpr::VK_PPC_HIGHERA: |
| Type = ELF::R_PPC64_ADDR16_HIGHERA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_HIGHEST: |
| Type = ELF::R_PPC64_ADDR16_HIGHEST; |
| break; |
| case MCSymbolRefExpr::VK_PPC_HIGHESTA: |
| Type = ELF::R_PPC64_ADDR16_HIGHESTA; |
| break; |
| case MCSymbolRefExpr::VK_GOT: |
| Type = ELF::R_PPC_GOT16; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_LO: |
| Type = ELF::R_PPC_GOT16_LO; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_HI: |
| Type = ELF::R_PPC_GOT16_HI; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_HA: |
| Type = ELF::R_PPC_GOT16_HA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TOC: |
| Type = ELF::R_PPC64_TOC16; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TOC_LO: |
| Type = ELF::R_PPC64_TOC16_LO; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TOC_HI: |
| Type = ELF::R_PPC64_TOC16_HI; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TOC_HA: |
| Type = ELF::R_PPC64_TOC16_HA; |
| break; |
| case MCSymbolRefExpr::VK_TPREL: |
| Type = ELF::R_PPC_TPREL16; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TPREL_LO: |
| Type = ELF::R_PPC_TPREL16_LO; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TPREL_HI: |
| Type = ELF::R_PPC_TPREL16_HI; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TPREL_HA: |
| Type = ELF::R_PPC_TPREL16_HA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TPREL_HIGH: |
| Type = ELF::R_PPC64_TPREL16_HIGH; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TPREL_HIGHA: |
| Type = ELF::R_PPC64_TPREL16_HIGHA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TPREL_HIGHER: |
| Type = ELF::R_PPC64_TPREL16_HIGHER; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TPREL_HIGHERA: |
| Type = ELF::R_PPC64_TPREL16_HIGHERA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TPREL_HIGHEST: |
| Type = ELF::R_PPC64_TPREL16_HIGHEST; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TPREL_HIGHESTA: |
| Type = ELF::R_PPC64_TPREL16_HIGHESTA; |
| break; |
| case MCSymbolRefExpr::VK_DTPREL: |
| Type = ELF::R_PPC64_DTPREL16; |
| break; |
| case MCSymbolRefExpr::VK_PPC_DTPREL_LO: |
| Type = ELF::R_PPC64_DTPREL16_LO; |
| break; |
| case MCSymbolRefExpr::VK_PPC_DTPREL_HI: |
| Type = ELF::R_PPC64_DTPREL16_HI; |
| break; |
| case MCSymbolRefExpr::VK_PPC_DTPREL_HA: |
| Type = ELF::R_PPC64_DTPREL16_HA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_DTPREL_HIGH: |
| Type = ELF::R_PPC64_DTPREL16_HIGH; |
| break; |
| case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHA: |
| Type = ELF::R_PPC64_DTPREL16_HIGHA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHER: |
| Type = ELF::R_PPC64_DTPREL16_HIGHER; |
| break; |
| case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHERA: |
| Type = ELF::R_PPC64_DTPREL16_HIGHERA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHEST: |
| Type = ELF::R_PPC64_DTPREL16_HIGHEST; |
| break; |
| case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHESTA: |
| Type = ELF::R_PPC64_DTPREL16_HIGHESTA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TLSGD: |
| if (is64Bit()) |
| Type = ELF::R_PPC64_GOT_TLSGD16; |
| else |
| Type = ELF::R_PPC_GOT_TLSGD16; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_LO: |
| Type = ELF::R_PPC64_GOT_TLSGD16_LO; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HI: |
| Type = ELF::R_PPC64_GOT_TLSGD16_HI; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HA: |
| Type = ELF::R_PPC64_GOT_TLSGD16_HA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TLSLD: |
| if (is64Bit()) |
| Type = ELF::R_PPC64_GOT_TLSLD16; |
| else |
| Type = ELF::R_PPC_GOT_TLSLD16; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO: |
| Type = ELF::R_PPC64_GOT_TLSLD16_LO; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HI: |
| Type = ELF::R_PPC64_GOT_TLSLD16_HI; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HA: |
| Type = ELF::R_PPC64_GOT_TLSLD16_HA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TPREL: |
| /* We don't have R_PPC64_GOT_TPREL16, but since GOT offsets |
| are always 4-aligned, we can use R_PPC64_GOT_TPREL16_DS. */ |
| Type = ELF::R_PPC64_GOT_TPREL16_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO: |
| /* We don't have R_PPC64_GOT_TPREL16_LO, but since GOT offsets |
| are always 4-aligned, we can use R_PPC64_GOT_TPREL16_LO_DS. */ |
| Type = ELF::R_PPC64_GOT_TPREL16_LO_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TPREL_HI: |
| Type = ELF::R_PPC64_GOT_TPREL16_HI; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_DTPREL: |
| /* We don't have R_PPC64_GOT_DTPREL16, but since GOT offsets |
| are always 4-aligned, we can use R_PPC64_GOT_DTPREL16_DS. */ |
| Type = ELF::R_PPC64_GOT_DTPREL16_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_LO: |
| /* We don't have R_PPC64_GOT_DTPREL16_LO, but since GOT offsets |
| are always 4-aligned, we can use R_PPC64_GOT_DTPREL16_LO_DS. */ |
| Type = ELF::R_PPC64_GOT_DTPREL16_LO_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TPREL_HA: |
| Type = ELF::R_PPC64_GOT_TPREL16_HA; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_HI: |
| Type = ELF::R_PPC64_GOT_DTPREL16_HI; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_HA: |
| Type = ELF::R_PPC64_GOT_DTPREL16_HA; |
| break; |
| } |
| break; |
| case PPC::fixup_ppc_half16ds: |
| switch (Modifier) { |
| default: llvm_unreachable("Unsupported Modifier"); |
| case MCSymbolRefExpr::VK_None: |
| Type = ELF::R_PPC64_ADDR16_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_LO: |
| Type = ELF::R_PPC64_ADDR16_LO_DS; |
| break; |
| case MCSymbolRefExpr::VK_GOT: |
| Type = ELF::R_PPC64_GOT16_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_LO: |
| Type = ELF::R_PPC64_GOT16_LO_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TOC: |
| Type = ELF::R_PPC64_TOC16_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TOC_LO: |
| Type = ELF::R_PPC64_TOC16_LO_DS; |
| break; |
| case MCSymbolRefExpr::VK_TPREL: |
| Type = ELF::R_PPC64_TPREL16_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TPREL_LO: |
| Type = ELF::R_PPC64_TPREL16_LO_DS; |
| break; |
| case MCSymbolRefExpr::VK_DTPREL: |
| Type = ELF::R_PPC64_DTPREL16_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_DTPREL_LO: |
| Type = ELF::R_PPC64_DTPREL16_LO_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TPREL: |
| Type = ELF::R_PPC64_GOT_TPREL16_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO: |
| Type = ELF::R_PPC64_GOT_TPREL16_LO_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_DTPREL: |
| Type = ELF::R_PPC64_GOT_DTPREL16_DS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_LO: |
| Type = ELF::R_PPC64_GOT_DTPREL16_LO_DS; |
| break; |
| } |
| break; |
| case PPC::fixup_ppc_nofixup: |
| switch (Modifier) { |
| default: llvm_unreachable("Unsupported Modifier"); |
| case MCSymbolRefExpr::VK_PPC_TLSGD: |
| if (is64Bit()) |
| Type = ELF::R_PPC64_TLSGD; |
| else |
| Type = ELF::R_PPC_TLSGD; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TLSLD: |
| if (is64Bit()) |
| Type = ELF::R_PPC64_TLSLD; |
| else |
| Type = ELF::R_PPC_TLSLD; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TLS: |
| if (is64Bit()) |
| Type = ELF::R_PPC64_TLS; |
| else |
| Type = ELF::R_PPC_TLS; |
| break; |
| case MCSymbolRefExpr::VK_PPC_TLS_PCREL: |
| Type = ELF::R_PPC64_TLS; |
| break; |
| } |
| break; |
| case PPC::fixup_ppc_imm34: |
| switch (Modifier) { |
| default: |
| report_fatal_error("Unsupported Modifier for fixup_ppc_imm34."); |
| case MCSymbolRefExpr::VK_DTPREL: |
| Type = ELF::R_PPC64_DTPREL34; |
| break; |
| case MCSymbolRefExpr::VK_TPREL: |
| Type = ELF::R_PPC64_TPREL34; |
| break; |
| } |
| break; |
| case FK_Data_8: |
| switch (Modifier) { |
| default: llvm_unreachable("Unsupported Modifier"); |
| case MCSymbolRefExpr::VK_PPC_TOCBASE: |
| Type = ELF::R_PPC64_TOC; |
| break; |
| case MCSymbolRefExpr::VK_None: |
| Type = ELF::R_PPC64_ADDR64; |
| break; |
| case MCSymbolRefExpr::VK_PPC_DTPMOD: |
| Type = ELF::R_PPC64_DTPMOD64; |
| break; |
| case MCSymbolRefExpr::VK_TPREL: |
| Type = ELF::R_PPC64_TPREL64; |
| break; |
| case MCSymbolRefExpr::VK_DTPREL: |
| Type = ELF::R_PPC64_DTPREL64; |
| break; |
| } |
| break; |
| case FK_Data_4: |
| Type = ELF::R_PPC_ADDR32; |
| break; |
| case FK_Data_2: |
| Type = ELF::R_PPC_ADDR16; |
| break; |
| } |
| } |
| return Type; |
| } |
| |
| bool PPCELFObjectWriter::needsRelocateWithSymbol(const MCSymbol &Sym, |
| unsigned Type) const { |
| switch (Type) { |
| default: |
| return false; |
| |
| case ELF::R_PPC_REL24: |
| case ELF::R_PPC64_REL24_NOTOC: |
| // If the target symbol has a local entry point, we must keep the |
| // target symbol to preserve that information for the linker. |
| // The "other" values are stored in the last 6 bits of the second byte. |
| // The traditional defines for STO values assume the full byte and thus |
| // the shift to pack it. |
| unsigned Other = cast<MCSymbolELF>(Sym).getOther() << 2; |
| return (Other & ELF::STO_PPC64_LOCAL_MASK) != 0; |
| } |
| } |
| |
| std::unique_ptr<MCObjectTargetWriter> |
| llvm::createPPCELFObjectWriter(bool Is64Bit, uint8_t OSABI) { |
| return std::make_unique<PPCELFObjectWriter>(Is64Bit, OSABI); |
| } |
