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//===- R600MCCodeEmitter.cpp - Code Emitter for R600->Cayman GPU families -===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
/// \file
///
/// The R600 code emitter produces machine code that can be executed
/// directly on the GPU device.
//
//===----------------------------------------------------------------------===//
#include "MCTargetDesc/AMDGPUFixupKinds.h"
#include "MCTargetDesc/AMDGPUMCTargetDesc.h"
#include "R600Defines.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCFixup.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstrDesc.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/EndianStream.h"
#include "llvm/Support/raw_ostream.h"
#include <cassert>
#include <cstdint>
using namespace llvm;
namespace {
class R600MCCodeEmitter : public MCCodeEmitter {
const MCRegisterInfo &MRI;
const MCInstrInfo &MCII;
public:
R600MCCodeEmitter(const MCInstrInfo &mcii, const MCRegisterInfo &mri)
: MRI(mri), MCII(mcii) {}
R600MCCodeEmitter(const R600MCCodeEmitter &) = delete;
R600MCCodeEmitter &operator=(const R600MCCodeEmitter &) = delete;
/// Encode the instruction and write it to the OS.
void encodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// \returns the encoding for an MCOperand.
uint64_t getMachineOpValue(const MCInst &MI, const MCOperand &MO,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
private:
void Emit(uint32_t value, raw_ostream &OS) const;
void Emit(uint64_t value, raw_ostream &OS) const;
unsigned getHWReg(unsigned regNo) const;
uint64_t getBinaryCodeForInstr(const MCInst &MI,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
uint64_t computeAvailableFeatures(const FeatureBitset &FB) const;
void verifyInstructionPredicates(const MCInst &MI,
uint64_t AvailableFeatures) const;
};
} // end anonymous namespace
enum RegElement {
ELEMENT_X = 0,
ELEMENT_Y,
ELEMENT_Z,
ELEMENT_W
};
enum FCInstr {
FC_IF_PREDICATE = 0,
FC_ELSE,
FC_ENDIF,
FC_BGNLOOP,
FC_ENDLOOP,
FC_BREAK_PREDICATE,
FC_CONTINUE
};
MCCodeEmitter *llvm::createR600MCCodeEmitter(const MCInstrInfo &MCII,
const MCRegisterInfo &MRI,
MCContext &Ctx) {
return new R600MCCodeEmitter(MCII, MRI);
}
void R600MCCodeEmitter::encodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
verifyInstructionPredicates(MI,
computeAvailableFeatures(STI.getFeatureBits()));
const MCInstrDesc &Desc = MCII.get(MI.getOpcode());
if (MI.getOpcode() == R600::RETURN ||
MI.getOpcode() == R600::FETCH_CLAUSE ||
MI.getOpcode() == R600::ALU_CLAUSE ||
MI.getOpcode() == R600::BUNDLE ||
MI.getOpcode() == R600::KILL) {
return;
} else if (IS_VTX(Desc)) {
uint64_t InstWord01 = getBinaryCodeForInstr(MI, Fixups, STI);
uint32_t InstWord2 = MI.getOperand(2).getImm(); // Offset
if (!(STI.getFeatureBits()[R600::FeatureCaymanISA])) {
InstWord2 |= 1 << 19; // Mega-Fetch bit
}
Emit(InstWord01, OS);
Emit(InstWord2, OS);
Emit((uint32_t) 0, OS);
} else if (IS_TEX(Desc)) {
int64_t Sampler = MI.getOperand(14).getImm();
int64_t SrcSelect[4] = {
MI.getOperand(2).getImm(),
MI.getOperand(3).getImm(),
MI.getOperand(4).getImm(),
MI.getOperand(5).getImm()
};
int64_t Offsets[3] = {
MI.getOperand(6).getImm() & 0x1F,
MI.getOperand(7).getImm() & 0x1F,
MI.getOperand(8).getImm() & 0x1F
};
uint64_t Word01 = getBinaryCodeForInstr(MI, Fixups, STI);
uint32_t Word2 = Sampler << 15 | SrcSelect[ELEMENT_X] << 20 |
SrcSelect[ELEMENT_Y] << 23 | SrcSelect[ELEMENT_Z] << 26 |
SrcSelect[ELEMENT_W] << 29 | Offsets[0] << 0 | Offsets[1] << 5 |
Offsets[2] << 10;
Emit(Word01, OS);
Emit(Word2, OS);
Emit((uint32_t) 0, OS);
} else {
uint64_t Inst = getBinaryCodeForInstr(MI, Fixups, STI);
if ((STI.getFeatureBits()[R600::FeatureR600ALUInst]) &&
((Desc.TSFlags & R600_InstFlag::OP1) ||
Desc.TSFlags & R600_InstFlag::OP2)) {
uint64_t ISAOpCode = Inst & (0x3FFULL << 39);
Inst &= ~(0x3FFULL << 39);
Inst |= ISAOpCode << 1;
}
Emit(Inst, OS);
}
}
void R600MCCodeEmitter::Emit(uint32_t Value, raw_ostream &OS) const {
support::endian::write(OS, Value, support::little);
}
void R600MCCodeEmitter::Emit(uint64_t Value, raw_ostream &OS) const {
support::endian::write(OS, Value, support::little);
}
unsigned R600MCCodeEmitter::getHWReg(unsigned RegNo) const {
return MRI.getEncodingValue(RegNo) & HW_REG_MASK;
}
uint64_t R600MCCodeEmitter::getMachineOpValue(const MCInst &MI,
const MCOperand &MO,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
if (MO.isReg()) {
if (HAS_NATIVE_OPERANDS(MCII.get(MI.getOpcode()).TSFlags))
return MRI.getEncodingValue(MO.getReg());
return getHWReg(MO.getReg());
}
if (MO.isExpr()) {
// We put rodata at the end of code section, then map the entire
// code secetion as vtx buf. Thus the section relative address is the
// correct one.
// Each R600 literal instruction has two operands
// We can't easily get the order of the current one, so compare against
// the first one and adjust offset.
const unsigned offset = (&MO == &MI.getOperand(0)) ? 0 : 4;
Fixups.push_back(MCFixup::create(offset, MO.getExpr(), FK_SecRel_4, MI.getLoc()));
return 0;
}
assert(MO.isImm());
return MO.getImm();
}
#define ENABLE_INSTR_PREDICATE_VERIFIER
#include "R600GenMCCodeEmitter.inc"