diff options
Diffstat (limited to 'contrib/llvm/lib/Target/MBlaze/MBlazeAsmBackend.cpp')
-rw-r--r-- | contrib/llvm/lib/Target/MBlaze/MBlazeAsmBackend.cpp | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/MBlaze/MBlazeAsmBackend.cpp b/contrib/llvm/lib/Target/MBlaze/MBlazeAsmBackend.cpp new file mode 100644 index 0000000..a4b21af --- /dev/null +++ b/contrib/llvm/lib/Target/MBlaze/MBlazeAsmBackend.cpp @@ -0,0 +1,163 @@ +//===-- MBlazeAsmBackend.cpp - MBlaze Assembler Backend -------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Target/TargetAsmBackend.h" +#include "MBlaze.h" +#include "MBlazeELFWriterInfo.h" +#include "llvm/ADT/Twine.h" +#include "llvm/MC/MCAssembler.h" +#include "llvm/MC/MCAsmLayout.h" +#include "llvm/MC/MCELFObjectWriter.h" +#include "llvm/MC/MCELFSymbolFlags.h" +#include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCObjectWriter.h" +#include "llvm/MC/MCSectionELF.h" +#include "llvm/MC/MCSectionMachO.h" +#include "llvm/MC/MCValue.h" +#include "llvm/Support/ELF.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/Target/TargetRegistry.h" +#include "llvm/Target/TargetAsmBackend.h" +using namespace llvm; + +static unsigned getFixupKindSize(unsigned Kind) { + switch (Kind) { + default: assert(0 && "invalid fixup kind!"); + case FK_Data_1: return 1; + case FK_PCRel_2: + case FK_Data_2: return 2; + case FK_PCRel_4: + case FK_Data_4: return 4; + case FK_Data_8: return 8; + } +} + + +namespace { +class MBlazeELFObjectWriter : public MCELFObjectTargetWriter { +public: + MBlazeELFObjectWriter(Triple::OSType OSType) + : MCELFObjectTargetWriter(/*is64Bit*/ false, OSType, ELF::EM_MBLAZE, + /*HasRelocationAddend*/ true) {} +}; + +class MBlazeAsmBackend : public TargetAsmBackend { +public: + MBlazeAsmBackend(const Target &T) + : TargetAsmBackend() { + } + + unsigned getNumFixupKinds() const { + return 2; + } + + bool MayNeedRelaxation(const MCInst &Inst) const; + + void RelaxInstruction(const MCInst &Inst, MCInst &Res) const; + + bool WriteNopData(uint64_t Count, MCObjectWriter *OW) const; + + unsigned getPointerSize() const { + return 4; + } +}; + +static unsigned getRelaxedOpcode(unsigned Op) { + switch (Op) { + default: return Op; + case MBlaze::ADDIK: return MBlaze::ADDIK32; + case MBlaze::ORI: return MBlaze::ORI32; + case MBlaze::BRLID: return MBlaze::BRLID32; + } +} + +bool MBlazeAsmBackend::MayNeedRelaxation(const MCInst &Inst) const { + if (getRelaxedOpcode(Inst.getOpcode()) == Inst.getOpcode()) + return false; + + bool hasExprOrImm = false; + for (unsigned i = 0; i < Inst.getNumOperands(); ++i) + hasExprOrImm |= Inst.getOperand(i).isExpr(); + + return hasExprOrImm; +} + +void MBlazeAsmBackend::RelaxInstruction(const MCInst &Inst, MCInst &Res) const { + Res = Inst; + Res.setOpcode(getRelaxedOpcode(Inst.getOpcode())); +} + +bool MBlazeAsmBackend::WriteNopData(uint64_t Count, MCObjectWriter *OW) const { + if ((Count % 4) != 0) + return false; + + for (uint64_t i = 0; i < Count; i += 4) + OW->Write32(0x00000000); + + return true; +} +} // end anonymous namespace + +namespace { +class ELFMBlazeAsmBackend : public MBlazeAsmBackend { +public: + Triple::OSType OSType; + ELFMBlazeAsmBackend(const Target &T, Triple::OSType _OSType) + : MBlazeAsmBackend(T), OSType(_OSType) { } + + void ApplyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize, + uint64_t Value) const; + + MCObjectWriter *createObjectWriter(raw_ostream &OS) const { + return createELFObjectWriter(new MBlazeELFObjectWriter(OSType), OS, + /*IsLittleEndian*/ false); + } +}; + +void ELFMBlazeAsmBackend::ApplyFixup(const MCFixup &Fixup, char *Data, + unsigned DataSize, uint64_t Value) const { + unsigned Size = getFixupKindSize(Fixup.getKind()); + + assert(Fixup.getOffset() + Size <= DataSize && + "Invalid fixup offset!"); + + char *data = Data + Fixup.getOffset(); + switch (Size) { + default: llvm_unreachable("Cannot fixup unknown value."); + case 1: llvm_unreachable("Cannot fixup 1 byte value."); + case 8: llvm_unreachable("Cannot fixup 8 byte value."); + + case 4: + *(data+7) = uint8_t(Value); + *(data+6) = uint8_t(Value >> 8); + *(data+3) = uint8_t(Value >> 16); + *(data+2) = uint8_t(Value >> 24); + break; + + case 2: + *(data+3) = uint8_t(Value >> 0); + *(data+2) = uint8_t(Value >> 8); + } +} +} // end anonymous namespace + +TargetAsmBackend *llvm::createMBlazeAsmBackend(const Target &T, + const std::string &TT) { + switch (Triple(TT).getOS()) { + case Triple::Darwin: + assert(0 && "Mac not supported on MBlaze"); + case Triple::MinGW32: + case Triple::Cygwin: + case Triple::Win32: + assert(0 && "Windows not supported on MBlaze"); + default: + return new ELFMBlazeAsmBackend(T, Triple(TT).getOS()); + } +} |