llvm-project/llvm/lib/Target/RISCV/MCTargetDesc/RISCVMCCodeEmitter.cpp

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//===-- RISCVMCCodeEmitter.cpp - Convert RISCV code to machine code -------===//
//
// 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 RISCVMCCodeEmitter class.
//
//===----------------------------------------------------------------------===//
#include "MCTargetDesc/RISCVMCTargetDesc.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/EndianStream.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
#define DEBUG_TYPE "mccodeemitter"
STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
namespace {
class RISCVMCCodeEmitter : public MCCodeEmitter {
RISCVMCCodeEmitter(const RISCVMCCodeEmitter &) = delete;
void operator=(const RISCVMCCodeEmitter &) = delete;
MCContext &Ctx;
public:
RISCVMCCodeEmitter(MCContext &ctx) : Ctx(ctx) {}
~RISCVMCCodeEmitter() override {}
void encodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const override;
/// TableGen'erated function for getting the binary encoding for an
/// instruction.
uint64_t getBinaryCodeForInstr(const MCInst &MI,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// Return binary encoding of operand. If the machine operand requires
/// relocation, record the relocation and return zero.
unsigned getMachineOpValue(const MCInst &MI, const MCOperand &MO,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
};
} // end anonymous namespace
MCCodeEmitter *llvm::createRISCVMCCodeEmitter(const MCInstrInfo &MCII,
const MCRegisterInfo &MRI,
MCContext &Ctx) {
return new RISCVMCCodeEmitter(Ctx);
}
void RISCVMCCodeEmitter::encodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// For now, we only support RISC-V instructions with 32-bit length
uint32_t Bits = getBinaryCodeForInstr(MI, Fixups, STI);
support::endian::Writer<support::little>(OS).write(Bits);
++MCNumEmitted; // Keep track of the # of mi's emitted.
}
unsigned
RISCVMCCodeEmitter::getMachineOpValue(const MCInst &MI, const MCOperand &MO,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
if (MO.isReg())
return Ctx.getRegisterInfo()->getEncodingValue(MO.getReg());
if (MO.isImm())
return static_cast<unsigned>(MO.getImm());
llvm_unreachable("Unhandled expression!");
return 0;
}
#include "RISCVGenMCCodeEmitter.inc"