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-rw-r--r--contrib/llvm-project/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp333
1 files changed, 333 insertions, 0 deletions
diff --git a/contrib/llvm-project/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp b/contrib/llvm-project/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
new file mode 100644
index 000000000000..232a06593238
--- /dev/null
+++ b/contrib/llvm-project/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
@@ -0,0 +1,333 @@
+//===-- X86ELFObjectWriter.cpp - X86 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/X86FixupKinds.h"
+#include "MCTargetDesc/X86MCTargetDesc.h"
+#include "llvm/BinaryFormat/ELF.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCELFObjectWriter.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCFixup.h"
+#include "llvm/MC/MCObjectWriter.h"
+#include "llvm/MC/MCValue.h"
+#include "llvm/Support/ErrorHandling.h"
+#include <cassert>
+#include <cstdint>
+
+using namespace llvm;
+
+namespace {
+
+class X86ELFObjectWriter : public MCELFObjectTargetWriter {
+public:
+ X86ELFObjectWriter(bool IsELF64, uint8_t OSABI, uint16_t EMachine);
+ ~X86ELFObjectWriter() override = default;
+
+protected:
+ unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
+ const MCFixup &Fixup, bool IsPCRel) const override;
+};
+
+} // end anonymous namespace
+
+X86ELFObjectWriter::X86ELFObjectWriter(bool IsELF64, uint8_t OSABI,
+ uint16_t EMachine)
+ : MCELFObjectTargetWriter(IsELF64, OSABI, EMachine,
+ // Only i386 and IAMCU use Rel instead of RelA.
+ /*HasRelocationAddend*/
+ (EMachine != ELF::EM_386) &&
+ (EMachine != ELF::EM_IAMCU)) {}
+
+enum X86_64RelType { RT64_NONE, RT64_64, RT64_32, RT64_32S, RT64_16, RT64_8 };
+
+static X86_64RelType getType64(unsigned Kind,
+ MCSymbolRefExpr::VariantKind &Modifier,
+ bool &IsPCRel) {
+ switch (Kind) {
+ default:
+ llvm_unreachable("Unimplemented");
+ case FK_NONE:
+ return RT64_NONE;
+ case X86::reloc_global_offset_table8:
+ Modifier = MCSymbolRefExpr::VK_GOT;
+ IsPCRel = true;
+ return RT64_64;
+ case FK_Data_8:
+ return RT64_64;
+ case X86::reloc_signed_4byte:
+ case X86::reloc_signed_4byte_relax:
+ if (Modifier == MCSymbolRefExpr::VK_None && !IsPCRel)
+ return RT64_32S;
+ return RT64_32;
+ case X86::reloc_global_offset_table:
+ Modifier = MCSymbolRefExpr::VK_GOT;
+ IsPCRel = true;
+ return RT64_32;
+ case FK_Data_4:
+ case FK_PCRel_4:
+ case X86::reloc_riprel_4byte:
+ case X86::reloc_riprel_4byte_relax:
+ case X86::reloc_riprel_4byte_relax_rex:
+ case X86::reloc_riprel_4byte_movq_load:
+ return RT64_32;
+ case X86::reloc_branch_4byte_pcrel:
+ Modifier = MCSymbolRefExpr::VK_PLT;
+ return RT64_32;
+ case FK_PCRel_2:
+ case FK_Data_2:
+ return RT64_16;
+ case FK_PCRel_1:
+ case FK_Data_1:
+ return RT64_8;
+ }
+}
+
+static void checkIs32(MCContext &Ctx, SMLoc Loc, X86_64RelType Type) {
+ if (Type != RT64_32)
+ Ctx.reportError(Loc,
+ "32 bit reloc applied to a field with a different size");
+}
+
+static unsigned getRelocType64(MCContext &Ctx, SMLoc Loc,
+ MCSymbolRefExpr::VariantKind Modifier,
+ X86_64RelType Type, bool IsPCRel,
+ unsigned Kind) {
+ switch (Modifier) {
+ default:
+ llvm_unreachable("Unimplemented");
+ case MCSymbolRefExpr::VK_None:
+ case MCSymbolRefExpr::VK_X86_ABS8:
+ switch (Type) {
+ case RT64_NONE:
+ if (Modifier == MCSymbolRefExpr::VK_None)
+ return ELF::R_X86_64_NONE;
+ llvm_unreachable("Unimplemented");
+ case RT64_64:
+ return IsPCRel ? ELF::R_X86_64_PC64 : ELF::R_X86_64_64;
+ case RT64_32:
+ return IsPCRel ? ELF::R_X86_64_PC32 : ELF::R_X86_64_32;
+ case RT64_32S:
+ return ELF::R_X86_64_32S;
+ case RT64_16:
+ return IsPCRel ? ELF::R_X86_64_PC16 : ELF::R_X86_64_16;
+ case RT64_8:
+ return IsPCRel ? ELF::R_X86_64_PC8 : ELF::R_X86_64_8;
+ }
+ llvm_unreachable("unexpected relocation type!");
+ case MCSymbolRefExpr::VK_GOT:
+ switch (Type) {
+ case RT64_64:
+ return IsPCRel ? ELF::R_X86_64_GOTPC64 : ELF::R_X86_64_GOT64;
+ case RT64_32:
+ return IsPCRel ? ELF::R_X86_64_GOTPC32 : ELF::R_X86_64_GOT32;
+ case RT64_32S:
+ case RT64_16:
+ case RT64_8:
+ case RT64_NONE:
+ llvm_unreachable("Unimplemented");
+ }
+ llvm_unreachable("unexpected relocation type!");
+ case MCSymbolRefExpr::VK_GOTOFF:
+ assert(Type == RT64_64);
+ assert(!IsPCRel);
+ return ELF::R_X86_64_GOTOFF64;
+ case MCSymbolRefExpr::VK_TPOFF:
+ assert(!IsPCRel);
+ switch (Type) {
+ case RT64_64:
+ return ELF::R_X86_64_TPOFF64;
+ case RT64_32:
+ return ELF::R_X86_64_TPOFF32;
+ case RT64_32S:
+ case RT64_16:
+ case RT64_8:
+ case RT64_NONE:
+ llvm_unreachable("Unimplemented");
+ }
+ llvm_unreachable("unexpected relocation type!");
+ case MCSymbolRefExpr::VK_DTPOFF:
+ assert(!IsPCRel);
+ switch (Type) {
+ case RT64_64:
+ return ELF::R_X86_64_DTPOFF64;
+ case RT64_32:
+ return ELF::R_X86_64_DTPOFF32;
+ case RT64_32S:
+ case RT64_16:
+ case RT64_8:
+ case RT64_NONE:
+ llvm_unreachable("Unimplemented");
+ }
+ llvm_unreachable("unexpected relocation type!");
+ case MCSymbolRefExpr::VK_SIZE:
+ assert(!IsPCRel);
+ switch (Type) {
+ case RT64_64:
+ return ELF::R_X86_64_SIZE64;
+ case RT64_32:
+ return ELF::R_X86_64_SIZE32;
+ case RT64_32S:
+ case RT64_16:
+ case RT64_8:
+ case RT64_NONE:
+ llvm_unreachable("Unimplemented");
+ }
+ llvm_unreachable("unexpected relocation type!");
+ case MCSymbolRefExpr::VK_TLSCALL:
+ return ELF::R_X86_64_TLSDESC_CALL;
+ case MCSymbolRefExpr::VK_TLSDESC:
+ return ELF::R_X86_64_GOTPC32_TLSDESC;
+ case MCSymbolRefExpr::VK_TLSGD:
+ checkIs32(Ctx, Loc, Type);
+ return ELF::R_X86_64_TLSGD;
+ case MCSymbolRefExpr::VK_GOTTPOFF:
+ checkIs32(Ctx, Loc, Type);
+ return ELF::R_X86_64_GOTTPOFF;
+ case MCSymbolRefExpr::VK_TLSLD:
+ checkIs32(Ctx, Loc, Type);
+ return ELF::R_X86_64_TLSLD;
+ case MCSymbolRefExpr::VK_PLT:
+ checkIs32(Ctx, Loc, Type);
+ return ELF::R_X86_64_PLT32;
+ case MCSymbolRefExpr::VK_GOTPCREL:
+ checkIs32(Ctx, Loc, Type);
+ // Older versions of ld.bfd/ld.gold/lld
+ // do not support GOTPCRELX/REX_GOTPCRELX,
+ // and we want to keep back-compatibility.
+ if (!Ctx.getAsmInfo()->canRelaxRelocations())
+ return ELF::R_X86_64_GOTPCREL;
+ switch (Kind) {
+ default:
+ return ELF::R_X86_64_GOTPCREL;
+ case X86::reloc_riprel_4byte_relax:
+ return ELF::R_X86_64_GOTPCRELX;
+ case X86::reloc_riprel_4byte_relax_rex:
+ case X86::reloc_riprel_4byte_movq_load:
+ return ELF::R_X86_64_REX_GOTPCRELX;
+ }
+ llvm_unreachable("unexpected relocation type!");
+ }
+}
+
+enum X86_32RelType { RT32_NONE, RT32_32, RT32_16, RT32_8 };
+
+static X86_32RelType getType32(X86_64RelType T) {
+ switch (T) {
+ case RT64_NONE:
+ return RT32_NONE;
+ case RT64_64:
+ llvm_unreachable("Unimplemented");
+ case RT64_32:
+ case RT64_32S:
+ return RT32_32;
+ case RT64_16:
+ return RT32_16;
+ case RT64_8:
+ return RT32_8;
+ }
+ llvm_unreachable("unexpected relocation type!");
+}
+
+static unsigned getRelocType32(MCContext &Ctx,
+ MCSymbolRefExpr::VariantKind Modifier,
+ X86_32RelType Type, bool IsPCRel,
+ unsigned Kind) {
+ switch (Modifier) {
+ default:
+ llvm_unreachable("Unimplemented");
+ case MCSymbolRefExpr::VK_None:
+ case MCSymbolRefExpr::VK_X86_ABS8:
+ switch (Type) {
+ case RT32_NONE:
+ if (Modifier == MCSymbolRefExpr::VK_None)
+ return ELF::R_386_NONE;
+ llvm_unreachable("Unimplemented");
+ case RT32_32:
+ return IsPCRel ? ELF::R_386_PC32 : ELF::R_386_32;
+ case RT32_16:
+ return IsPCRel ? ELF::R_386_PC16 : ELF::R_386_16;
+ case RT32_8:
+ return IsPCRel ? ELF::R_386_PC8 : ELF::R_386_8;
+ }
+ llvm_unreachable("unexpected relocation type!");
+ case MCSymbolRefExpr::VK_GOT:
+ assert(Type == RT32_32);
+ if (IsPCRel)
+ return ELF::R_386_GOTPC;
+ // Older versions of ld.bfd/ld.gold/lld do not support R_386_GOT32X and we
+ // want to maintain compatibility.
+ if (!Ctx.getAsmInfo()->canRelaxRelocations())
+ return ELF::R_386_GOT32;
+
+ return Kind == X86::reloc_signed_4byte_relax ? ELF::R_386_GOT32X
+ : ELF::R_386_GOT32;
+ case MCSymbolRefExpr::VK_GOTOFF:
+ assert(Type == RT32_32);
+ assert(!IsPCRel);
+ return ELF::R_386_GOTOFF;
+ case MCSymbolRefExpr::VK_TLSCALL:
+ return ELF::R_386_TLS_DESC_CALL;
+ case MCSymbolRefExpr::VK_TLSDESC:
+ return ELF::R_386_TLS_GOTDESC;
+ case MCSymbolRefExpr::VK_TPOFF:
+ assert(Type == RT32_32);
+ assert(!IsPCRel);
+ return ELF::R_386_TLS_LE_32;
+ case MCSymbolRefExpr::VK_DTPOFF:
+ assert(Type == RT32_32);
+ assert(!IsPCRel);
+ return ELF::R_386_TLS_LDO_32;
+ case MCSymbolRefExpr::VK_TLSGD:
+ assert(Type == RT32_32);
+ assert(!IsPCRel);
+ return ELF::R_386_TLS_GD;
+ case MCSymbolRefExpr::VK_GOTTPOFF:
+ assert(Type == RT32_32);
+ assert(!IsPCRel);
+ return ELF::R_386_TLS_IE_32;
+ case MCSymbolRefExpr::VK_PLT:
+ assert(Type == RT32_32);
+ return ELF::R_386_PLT32;
+ case MCSymbolRefExpr::VK_INDNTPOFF:
+ assert(Type == RT32_32);
+ assert(!IsPCRel);
+ return ELF::R_386_TLS_IE;
+ case MCSymbolRefExpr::VK_NTPOFF:
+ assert(Type == RT32_32);
+ assert(!IsPCRel);
+ return ELF::R_386_TLS_LE;
+ case MCSymbolRefExpr::VK_GOTNTPOFF:
+ assert(Type == RT32_32);
+ assert(!IsPCRel);
+ return ELF::R_386_TLS_GOTIE;
+ case MCSymbolRefExpr::VK_TLSLDM:
+ assert(Type == RT32_32);
+ assert(!IsPCRel);
+ return ELF::R_386_TLS_LDM;
+ }
+}
+
+unsigned X86ELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
+ const MCFixup &Fixup,
+ bool IsPCRel) const {
+ MCSymbolRefExpr::VariantKind Modifier = Target.getAccessVariant();
+ unsigned Kind = Fixup.getKind();
+ X86_64RelType Type = getType64(Kind, Modifier, IsPCRel);
+ if (getEMachine() == ELF::EM_X86_64)
+ return getRelocType64(Ctx, Fixup.getLoc(), Modifier, Type, IsPCRel, Kind);
+
+ assert((getEMachine() == ELF::EM_386 || getEMachine() == ELF::EM_IAMCU) &&
+ "Unsupported ELF machine type.");
+ return getRelocType32(Ctx, Modifier, getType32(Type), IsPCRel, Kind);
+}
+
+std::unique_ptr<MCObjectTargetWriter>
+llvm::createX86ELFObjectWriter(bool IsELF64, uint8_t OSABI, uint16_t EMachine) {
+ return llvm::make_unique<X86ELFObjectWriter>(IsELF64, OSABI, EMachine);
+}
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