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Diffstat (limited to 'contrib/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp')
| -rw-r--r-- | contrib/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp | 425 |
1 files changed, 425 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp b/contrib/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp new file mode 100644 index 0000000..d8e6128 --- /dev/null +++ b/contrib/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp @@ -0,0 +1,425 @@ +//===-- MipsAsmBackend.cpp - Mips Asm Backend ----------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements the MipsAsmBackend class. +// +//===----------------------------------------------------------------------===// +// + +#include "MCTargetDesc/MipsFixupKinds.h" +#include "MCTargetDesc/MipsAsmBackend.h" +#include "MCTargetDesc/MipsMCTargetDesc.h" +#include "llvm/MC/MCAsmBackend.h" +#include "llvm/MC/MCAssembler.h" +#include "llvm/MC/MCContext.h" +#include "llvm/MC/MCDirectives.h" +#include "llvm/MC/MCELFObjectWriter.h" +#include "llvm/MC/MCFixupKindInfo.h" +#include "llvm/MC/MCObjectWriter.h" +#include "llvm/MC/MCSubtargetInfo.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/MathExtras.h" +#include "llvm/Support/raw_ostream.h" + +using namespace llvm; + +// Prepare value for the target space for it +static unsigned adjustFixupValue(const MCFixup &Fixup, uint64_t Value, + MCContext *Ctx = nullptr) { + + unsigned Kind = Fixup.getKind(); + + // Add/subtract and shift + switch (Kind) { + default: + return 0; + case FK_Data_2: + case FK_GPRel_4: + case FK_Data_4: + case FK_Data_8: + case Mips::fixup_Mips_LO16: + case Mips::fixup_Mips_GPREL16: + case Mips::fixup_Mips_GPOFF_HI: + case Mips::fixup_Mips_GPOFF_LO: + case Mips::fixup_Mips_GOT_PAGE: + case Mips::fixup_Mips_GOT_OFST: + case Mips::fixup_Mips_GOT_DISP: + case Mips::fixup_Mips_GOT_LO16: + case Mips::fixup_Mips_CALL_LO16: + case Mips::fixup_MICROMIPS_LO16: + case Mips::fixup_MICROMIPS_GOT_PAGE: + case Mips::fixup_MICROMIPS_GOT_OFST: + case Mips::fixup_MICROMIPS_GOT_DISP: + case Mips::fixup_MIPS_PCLO16: + break; + case Mips::fixup_Mips_PC16: + // So far we are only using this type for branches. + // For branches we start 1 instruction after the branch + // so the displacement will be one instruction size less. + Value -= 4; + // The displacement is then divided by 4 to give us an 18 bit + // address range. Forcing a signed division because Value can be negative. + Value = (int64_t)Value / 4; + // We now check if Value can be encoded as a 16-bit signed immediate. + if (!isIntN(16, Value) && Ctx) + Ctx->FatalError(Fixup.getLoc(), "out of range PC16 fixup"); + break; + case Mips::fixup_MIPS_PC19_S2: + // Forcing a signed division because Value can be negative. + Value = (int64_t)Value / 4; + // We now check if Value can be encoded as a 19-bit signed immediate. + if (!isIntN(19, Value) && Ctx) + Ctx->FatalError(Fixup.getLoc(), "out of range PC19 fixup"); + break; + case Mips::fixup_Mips_26: + // So far we are only using this type for jumps. + // The displacement is then divided by 4 to give us an 28 bit + // address range. + Value >>= 2; + break; + case Mips::fixup_Mips_HI16: + case Mips::fixup_Mips_GOT_Local: + case Mips::fixup_Mips_GOT_HI16: + case Mips::fixup_Mips_CALL_HI16: + case Mips::fixup_MICROMIPS_HI16: + case Mips::fixup_MIPS_PCHI16: + // Get the 2nd 16-bits. Also add 1 if bit 15 is 1. + Value = ((Value + 0x8000) >> 16) & 0xffff; + break; + case Mips::fixup_Mips_HIGHER: + // Get the 3rd 16-bits. + Value = ((Value + 0x80008000LL) >> 32) & 0xffff; + break; + case Mips::fixup_Mips_HIGHEST: + // Get the 4th 16-bits. + Value = ((Value + 0x800080008000LL) >> 48) & 0xffff; + break; + case Mips::fixup_MICROMIPS_26_S1: + Value >>= 1; + break; + case Mips::fixup_MICROMIPS_PC16_S1: + Value -= 4; + // Forcing a signed division because Value can be negative. + Value = (int64_t)Value / 2; + // We now check if Value can be encoded as a 16-bit signed immediate. + if (!isIntN(16, Value) && Ctx) + Ctx->FatalError(Fixup.getLoc(), "out of range PC16 fixup"); + break; + case Mips::fixup_MIPS_PC18_S3: + // Forcing a signed division because Value can be negative. + Value = (int64_t)Value / 8; + // We now check if Value can be encoded as a 18-bit signed immediate. + if (!isIntN(18, Value) && Ctx) + Ctx->FatalError(Fixup.getLoc(), "out of range PC18 fixup"); + break; + case Mips::fixup_MIPS_PC21_S2: + Value -= 4; + // Forcing a signed division because Value can be negative. + Value = (int64_t) Value / 4; + // We now check if Value can be encoded as a 21-bit signed immediate. + if (!isIntN(21, Value) && Ctx) + Ctx->FatalError(Fixup.getLoc(), "out of range PC21 fixup"); + break; + case Mips::fixup_MIPS_PC26_S2: + Value -= 4; + // Forcing a signed division because Value can be negative. + Value = (int64_t) Value / 4; + // We now check if Value can be encoded as a 26-bit signed immediate. + if (!isIntN(26, Value) && Ctx) + Ctx->FatalError(Fixup.getLoc(), "out of range PC26 fixup"); + break; + } + + return Value; +} + +MCObjectWriter *MipsAsmBackend::createObjectWriter(raw_ostream &OS) const { + return createMipsELFObjectWriter(OS, + MCELFObjectTargetWriter::getOSABI(OSType), IsLittle, Is64Bit); +} + +// Little-endian fixup data byte ordering: +// mips32r2: a | b | x | x +// microMIPS: x | x | a | b + +static bool needsMMLEByteOrder(unsigned Kind) { + return Kind >= Mips::fixup_MICROMIPS_26_S1 && + Kind < Mips::LastTargetFixupKind; +} + +// Calculate index for microMIPS specific little endian byte order +static unsigned calculateMMLEIndex(unsigned i) { + assert(i <= 3 && "Index out of range!"); + + return (1 - i / 2) * 2 + i % 2; +} + +/// ApplyFixup - Apply the \p Value for given \p Fixup into the provided +/// data fragment, at the offset specified by the fixup and following the +/// fixup kind as appropriate. +void MipsAsmBackend::applyFixup(const MCFixup &Fixup, char *Data, + unsigned DataSize, uint64_t Value, + bool IsPCRel) const { + MCFixupKind Kind = Fixup.getKind(); + Value = adjustFixupValue(Fixup, Value); + + if (!Value) + return; // Doesn't change encoding. + + // Where do we start in the object + unsigned Offset = Fixup.getOffset(); + // Number of bytes we need to fixup + unsigned NumBytes = (getFixupKindInfo(Kind).TargetSize + 7) / 8; + // Used to point to big endian bytes + unsigned FullSize; + + switch ((unsigned)Kind) { + case FK_Data_2: + case Mips::fixup_Mips_16: + FullSize = 2; + break; + case FK_Data_8: + case Mips::fixup_Mips_64: + FullSize = 8; + break; + case FK_Data_4: + default: + FullSize = 4; + break; + } + + // Grab current value, if any, from bits. + uint64_t CurVal = 0; + + bool microMipsLEByteOrder = needsMMLEByteOrder((unsigned) Kind); + + for (unsigned i = 0; i != NumBytes; ++i) { + unsigned Idx = IsLittle ? (microMipsLEByteOrder ? calculateMMLEIndex(i) + : i) + : (FullSize - 1 - i); + CurVal |= (uint64_t)((uint8_t)Data[Offset + Idx]) << (i*8); + } + + uint64_t Mask = ((uint64_t)(-1) >> + (64 - getFixupKindInfo(Kind).TargetSize)); + CurVal |= Value & Mask; + + // Write out the fixed up bytes back to the code/data bits. + for (unsigned i = 0; i != NumBytes; ++i) { + unsigned Idx = IsLittle ? (microMipsLEByteOrder ? calculateMMLEIndex(i) + : i) + : (FullSize - 1 - i); + Data[Offset + Idx] = (uint8_t)((CurVal >> (i*8)) & 0xff); + } +} + +const MCFixupKindInfo &MipsAsmBackend:: +getFixupKindInfo(MCFixupKind Kind) const { + const static MCFixupKindInfo LittleEndianInfos[Mips::NumTargetFixupKinds] = { + // This table *must* be in same the order of fixup_* kinds in + // MipsFixupKinds.h. + // + // name offset bits flags + { "fixup_Mips_16", 0, 16, 0 }, + { "fixup_Mips_32", 0, 32, 0 }, + { "fixup_Mips_REL32", 0, 32, 0 }, + { "fixup_Mips_26", 0, 26, 0 }, + { "fixup_Mips_HI16", 0, 16, 0 }, + { "fixup_Mips_LO16", 0, 16, 0 }, + { "fixup_Mips_GPREL16", 0, 16, 0 }, + { "fixup_Mips_LITERAL", 0, 16, 0 }, + { "fixup_Mips_GOT_Global", 0, 16, 0 }, + { "fixup_Mips_GOT_Local", 0, 16, 0 }, + { "fixup_Mips_PC16", 0, 16, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_Mips_CALL16", 0, 16, 0 }, + { "fixup_Mips_GPREL32", 0, 32, 0 }, + { "fixup_Mips_SHIFT5", 6, 5, 0 }, + { "fixup_Mips_SHIFT6", 6, 5, 0 }, + { "fixup_Mips_64", 0, 64, 0 }, + { "fixup_Mips_TLSGD", 0, 16, 0 }, + { "fixup_Mips_GOTTPREL", 0, 16, 0 }, + { "fixup_Mips_TPREL_HI", 0, 16, 0 }, + { "fixup_Mips_TPREL_LO", 0, 16, 0 }, + { "fixup_Mips_TLSLDM", 0, 16, 0 }, + { "fixup_Mips_DTPREL_HI", 0, 16, 0 }, + { "fixup_Mips_DTPREL_LO", 0, 16, 0 }, + { "fixup_Mips_Branch_PCRel", 0, 16, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_Mips_GPOFF_HI", 0, 16, 0 }, + { "fixup_Mips_GPOFF_LO", 0, 16, 0 }, + { "fixup_Mips_GOT_PAGE", 0, 16, 0 }, + { "fixup_Mips_GOT_OFST", 0, 16, 0 }, + { "fixup_Mips_GOT_DISP", 0, 16, 0 }, + { "fixup_Mips_HIGHER", 0, 16, 0 }, + { "fixup_Mips_HIGHEST", 0, 16, 0 }, + { "fixup_Mips_GOT_HI16", 0, 16, 0 }, + { "fixup_Mips_GOT_LO16", 0, 16, 0 }, + { "fixup_Mips_CALL_HI16", 0, 16, 0 }, + { "fixup_Mips_CALL_LO16", 0, 16, 0 }, + { "fixup_Mips_PC18_S3", 0, 18, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MIPS_PC19_S2", 0, 19, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MIPS_PC21_S2", 0, 21, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MIPS_PC26_S2", 0, 26, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MIPS_PCHI16", 0, 16, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MIPS_PCLO16", 0, 16, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MICROMIPS_26_S1", 0, 26, 0 }, + { "fixup_MICROMIPS_HI16", 0, 16, 0 }, + { "fixup_MICROMIPS_LO16", 0, 16, 0 }, + { "fixup_MICROMIPS_GOT16", 0, 16, 0 }, + { "fixup_MICROMIPS_PC16_S1", 0, 16, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MICROMIPS_CALL16", 0, 16, 0 }, + { "fixup_MICROMIPS_GOT_DISP", 0, 16, 0 }, + { "fixup_MICROMIPS_GOT_PAGE", 0, 16, 0 }, + { "fixup_MICROMIPS_GOT_OFST", 0, 16, 0 }, + { "fixup_MICROMIPS_TLS_GD", 0, 16, 0 }, + { "fixup_MICROMIPS_TLS_LDM", 0, 16, 0 }, + { "fixup_MICROMIPS_TLS_DTPREL_HI16", 0, 16, 0 }, + { "fixup_MICROMIPS_TLS_DTPREL_LO16", 0, 16, 0 }, + { "fixup_MICROMIPS_TLS_TPREL_HI16", 0, 16, 0 }, + { "fixup_MICROMIPS_TLS_TPREL_LO16", 0, 16, 0 } + }; + + const static MCFixupKindInfo BigEndianInfos[Mips::NumTargetFixupKinds] = { + // This table *must* be in same the order of fixup_* kinds in + // MipsFixupKinds.h. + // + // name offset bits flags + { "fixup_Mips_16", 16, 16, 0 }, + { "fixup_Mips_32", 0, 32, 0 }, + { "fixup_Mips_REL32", 0, 32, 0 }, + { "fixup_Mips_26", 6, 26, 0 }, + { "fixup_Mips_HI16", 16, 16, 0 }, + { "fixup_Mips_LO16", 16, 16, 0 }, + { "fixup_Mips_GPREL16", 16, 16, 0 }, + { "fixup_Mips_LITERAL", 16, 16, 0 }, + { "fixup_Mips_GOT_Global", 16, 16, 0 }, + { "fixup_Mips_GOT_Local", 16, 16, 0 }, + { "fixup_Mips_PC16", 16, 16, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_Mips_CALL16", 16, 16, 0 }, + { "fixup_Mips_GPREL32", 0, 32, 0 }, + { "fixup_Mips_SHIFT5", 21, 5, 0 }, + { "fixup_Mips_SHIFT6", 21, 5, 0 }, + { "fixup_Mips_64", 0, 64, 0 }, + { "fixup_Mips_TLSGD", 16, 16, 0 }, + { "fixup_Mips_GOTTPREL", 16, 16, 0 }, + { "fixup_Mips_TPREL_HI", 16, 16, 0 }, + { "fixup_Mips_TPREL_LO", 16, 16, 0 }, + { "fixup_Mips_TLSLDM", 16, 16, 0 }, + { "fixup_Mips_DTPREL_HI", 16, 16, 0 }, + { "fixup_Mips_DTPREL_LO", 16, 16, 0 }, + { "fixup_Mips_Branch_PCRel",16, 16, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_Mips_GPOFF_HI", 16, 16, 0 }, + { "fixup_Mips_GPOFF_LO", 16, 16, 0 }, + { "fixup_Mips_GOT_PAGE", 16, 16, 0 }, + { "fixup_Mips_GOT_OFST", 16, 16, 0 }, + { "fixup_Mips_GOT_DISP", 16, 16, 0 }, + { "fixup_Mips_HIGHER", 16, 16, 0 }, + { "fixup_Mips_HIGHEST", 16, 16, 0 }, + { "fixup_Mips_GOT_HI16", 16, 16, 0 }, + { "fixup_Mips_GOT_LO16", 16, 16, 0 }, + { "fixup_Mips_CALL_HI16", 16, 16, 0 }, + { "fixup_Mips_CALL_LO16", 16, 16, 0 }, + { "fixup_Mips_PC18_S3", 14, 18, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MIPS_PC19_S2", 13, 19, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MIPS_PC21_S2", 11, 21, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MIPS_PC26_S2", 6, 26, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MIPS_PCHI16", 16, 16, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MIPS_PCLO16", 16, 16, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MICROMIPS_26_S1", 6, 26, 0 }, + { "fixup_MICROMIPS_HI16", 16, 16, 0 }, + { "fixup_MICROMIPS_LO16", 16, 16, 0 }, + { "fixup_MICROMIPS_GOT16", 16, 16, 0 }, + { "fixup_MICROMIPS_PC16_S1",16, 16, MCFixupKindInfo::FKF_IsPCRel }, + { "fixup_MICROMIPS_CALL16", 16, 16, 0 }, + { "fixup_MICROMIPS_GOT_DISP", 16, 16, 0 }, + { "fixup_MICROMIPS_GOT_PAGE", 16, 16, 0 }, + { "fixup_MICROMIPS_GOT_OFST", 16, 16, 0 }, + { "fixup_MICROMIPS_TLS_GD", 16, 16, 0 }, + { "fixup_MICROMIPS_TLS_LDM", 16, 16, 0 }, + { "fixup_MICROMIPS_TLS_DTPREL_HI16", 16, 16, 0 }, + { "fixup_MICROMIPS_TLS_DTPREL_LO16", 16, 16, 0 }, + { "fixup_MICROMIPS_TLS_TPREL_HI16", 16, 16, 0 }, + { "fixup_MICROMIPS_TLS_TPREL_LO16", 16, 16, 0 } + }; + + if (Kind < FirstTargetFixupKind) + return MCAsmBackend::getFixupKindInfo(Kind); + + assert(unsigned(Kind - FirstTargetFixupKind) < getNumFixupKinds() && + "Invalid kind!"); + + if (IsLittle) + return LittleEndianInfos[Kind - FirstTargetFixupKind]; + return BigEndianInfos[Kind - FirstTargetFixupKind]; +} + +/// WriteNopData - Write an (optimal) nop sequence of Count bytes +/// to the given output. If the target cannot generate such a sequence, +/// it should return an error. +/// +/// \return - True on success. +bool MipsAsmBackend::writeNopData(uint64_t Count, MCObjectWriter *OW) const { + // Check for a less than instruction size number of bytes + // FIXME: 16 bit instructions are not handled yet here. + // We shouldn't be using a hard coded number for instruction size. + if (Count % 4) return false; + + uint64_t NumNops = Count / 4; + for (uint64_t i = 0; i != NumNops; ++i) + OW->Write32(0); + return true; +} + +/// processFixupValue - Target hook to process the literal value of a fixup +/// if necessary. +void MipsAsmBackend::processFixupValue(const MCAssembler &Asm, + const MCAsmLayout &Layout, + const MCFixup &Fixup, + const MCFragment *DF, + const MCValue &Target, + uint64_t &Value, + bool &IsResolved) { + // At this point we'll ignore the value returned by adjustFixupValue as + // we are only checking if the fixup can be applied correctly. We have + // access to MCContext from here which allows us to report a fatal error + // with *possibly* a source code location. + (void)adjustFixupValue(Fixup, Value, &Asm.getContext()); +} + +// MCAsmBackend +MCAsmBackend *llvm::createMipsAsmBackendEL32(const Target &T, + const MCRegisterInfo &MRI, + StringRef TT, + StringRef CPU) { + return new MipsAsmBackend(T, Triple(TT).getOS(), + /*IsLittle*/true, /*Is64Bit*/false); +} + +MCAsmBackend *llvm::createMipsAsmBackendEB32(const Target &T, + const MCRegisterInfo &MRI, + StringRef TT, + StringRef CPU) { + return new MipsAsmBackend(T, Triple(TT).getOS(), + /*IsLittle*/false, /*Is64Bit*/false); +} + +MCAsmBackend *llvm::createMipsAsmBackendEL64(const Target &T, + const MCRegisterInfo &MRI, + StringRef TT, + StringRef CPU) { + return new MipsAsmBackend(T, Triple(TT).getOS(), + /*IsLittle*/true, /*Is64Bit*/true); +} + +MCAsmBackend *llvm::createMipsAsmBackendEB64(const Target &T, + const MCRegisterInfo &MRI, + StringRef TT, + StringRef CPU) { + return new MipsAsmBackend(T, Triple(TT).getOS(), + /*IsLittle*/false, /*Is64Bit*/true); +} |
