llvm-6502/lib/Target/PowerPC/MCTargetDesc/PPCMCCodeEmitter.cpp
Benjamin Kramer 7ec7c7d865 Replace custom fixed endian to raw_ostream emission with EndianStream.
Less code, clearer and more efficient. No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239040 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-04 15:03:02 +00:00

361 lines
15 KiB
C++

//===-- PPCMCCodeEmitter.cpp - Convert PPC 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 PPCMCCodeEmitter class.
//
//===----------------------------------------------------------------------===//
#include "MCTargetDesc/PPCMCTargetDesc.h"
#include "MCTargetDesc/PPCFixupKinds.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/MCInstrInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/Support/EndianStream.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetOpcodes.h"
using namespace llvm;
#define DEBUG_TYPE "mccodeemitter"
STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
namespace {
class PPCMCCodeEmitter : public MCCodeEmitter {
PPCMCCodeEmitter(const PPCMCCodeEmitter &) = delete;
void operator=(const PPCMCCodeEmitter &) = delete;
const MCInstrInfo &MCII;
const MCContext &CTX;
bool IsLittleEndian;
public:
PPCMCCodeEmitter(const MCInstrInfo &mcii, MCContext &ctx)
: MCII(mcii), CTX(ctx),
IsLittleEndian(ctx.getAsmInfo()->isLittleEndian()) {}
~PPCMCCodeEmitter() override {}
unsigned getDirectBrEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getCondBrEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getAbsDirectBrEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getAbsCondBrEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getImm16Encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getMemRIEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getMemRIXEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getSPE8DisEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getSPE4DisEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getSPE2DisEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getTLSRegEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getTLSCallEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned get_crbitm_encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
/// getMachineOpValue - 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;
// getBinaryCodeForInstr - TableGen'erated function for getting the
// binary encoding for an instruction.
uint64_t getBinaryCodeForInstr(const MCInst &MI,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
void encodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const override {
// For fast-isel, a float COPY_TO_REGCLASS can survive this long.
// It's just a nop to keep the register classes happy, so don't
// generate anything.
unsigned Opcode = MI.getOpcode();
const MCInstrDesc &Desc = MCII.get(Opcode);
if (Opcode == TargetOpcode::COPY_TO_REGCLASS)
return;
uint64_t Bits = getBinaryCodeForInstr(MI, Fixups, STI);
// Output the constant in big/little endian byte order.
unsigned Size = Desc.getSize();
switch (Size) {
case 4:
if (IsLittleEndian) {
support::endian::Writer<support::little>(OS).write<uint32_t>(Bits);
} else {
support::endian::Writer<support::big>(OS).write<uint32_t>(Bits);
}
break;
case 8:
// If we emit a pair of instructions, the first one is
// always in the top 32 bits, even on little-endian.
if (IsLittleEndian) {
uint64_t Swapped = (Bits << 32) | (Bits >> 32);
support::endian::Writer<support::little>(OS).write<uint64_t>(Swapped);
} else {
support::endian::Writer<support::big>(OS).write<uint64_t>(Bits);
}
break;
default:
llvm_unreachable ("Invalid instruction size");
}
++MCNumEmitted; // Keep track of the # of mi's emitted.
}
};
} // end anonymous namespace
MCCodeEmitter *llvm::createPPCMCCodeEmitter(const MCInstrInfo &MCII,
const MCRegisterInfo &MRI,
MCContext &Ctx) {
return new PPCMCCodeEmitter(MCII, Ctx);
}
unsigned PPCMCCodeEmitter::
getDirectBrEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isReg() || MO.isImm()) return getMachineOpValue(MI, MO, Fixups, STI);
// Add a fixup for the branch target.
Fixups.push_back(MCFixup::create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_br24));
return 0;
}
unsigned PPCMCCodeEmitter::getCondBrEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isReg() || MO.isImm()) return getMachineOpValue(MI, MO, Fixups, STI);
// Add a fixup for the branch target.
Fixups.push_back(MCFixup::create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_brcond14));
return 0;
}
unsigned PPCMCCodeEmitter::
getAbsDirectBrEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isReg() || MO.isImm()) return getMachineOpValue(MI, MO, Fixups, STI);
// Add a fixup for the branch target.
Fixups.push_back(MCFixup::create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_br24abs));
return 0;
}
unsigned PPCMCCodeEmitter::
getAbsCondBrEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isReg() || MO.isImm()) return getMachineOpValue(MI, MO, Fixups, STI);
// Add a fixup for the branch target.
Fixups.push_back(MCFixup::create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_brcond14abs));
return 0;
}
unsigned PPCMCCodeEmitter::getImm16Encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isReg() || MO.isImm()) return getMachineOpValue(MI, MO, Fixups, STI);
// Add a fixup for the immediate field.
Fixups.push_back(MCFixup::create(IsLittleEndian? 0 : 2, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_half16));
return 0;
}
unsigned PPCMCCodeEmitter::getMemRIEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// Encode (imm, reg) as a memri, which has the low 16-bits as the
// displacement and the next 5 bits as the register #.
assert(MI.getOperand(OpNo+1).isReg());
unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI) << 16;
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isImm())
return (getMachineOpValue(MI, MO, Fixups, STI) & 0xFFFF) | RegBits;
// Add a fixup for the displacement field.
Fixups.push_back(MCFixup::create(IsLittleEndian? 0 : 2, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_half16));
return RegBits;
}
unsigned PPCMCCodeEmitter::getMemRIXEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// Encode (imm, reg) as a memrix, which has the low 14-bits as the
// displacement and the next 5 bits as the register #.
assert(MI.getOperand(OpNo+1).isReg());
unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI) << 14;
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isImm())
return ((getMachineOpValue(MI, MO, Fixups, STI) >> 2) & 0x3FFF) | RegBits;
// Add a fixup for the displacement field.
Fixups.push_back(MCFixup::create(IsLittleEndian? 0 : 2, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_half16ds));
return RegBits;
}
unsigned PPCMCCodeEmitter::getSPE8DisEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI)
const {
// Encode (imm, reg) as a spe8dis, which has the low 5-bits of (imm / 8)
// as the displacement and the next 5 bits as the register #.
assert(MI.getOperand(OpNo+1).isReg());
uint32_t RegBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI) << 5;
const MCOperand &MO = MI.getOperand(OpNo);
assert(MO.isImm());
uint32_t Imm = getMachineOpValue(MI, MO, Fixups, STI) >> 3;
return reverseBits(Imm | RegBits) >> 22;
}
unsigned PPCMCCodeEmitter::getSPE4DisEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI)
const {
// Encode (imm, reg) as a spe4dis, which has the low 5-bits of (imm / 4)
// as the displacement and the next 5 bits as the register #.
assert(MI.getOperand(OpNo+1).isReg());
uint32_t RegBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI) << 5;
const MCOperand &MO = MI.getOperand(OpNo);
assert(MO.isImm());
uint32_t Imm = getMachineOpValue(MI, MO, Fixups, STI) >> 2;
return reverseBits(Imm | RegBits) >> 22;
}
unsigned PPCMCCodeEmitter::getSPE2DisEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI)
const {
// Encode (imm, reg) as a spe2dis, which has the low 5-bits of (imm / 2)
// as the displacement and the next 5 bits as the register #.
assert(MI.getOperand(OpNo+1).isReg());
uint32_t RegBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI) << 5;
const MCOperand &MO = MI.getOperand(OpNo);
assert(MO.isImm());
uint32_t Imm = getMachineOpValue(MI, MO, Fixups, STI) >> 1;
return reverseBits(Imm | RegBits) >> 22;
}
unsigned PPCMCCodeEmitter::getTLSRegEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isReg()) return getMachineOpValue(MI, MO, Fixups, STI);
// Add a fixup for the TLS register, which simply provides a relocation
// hint to the linker that this statement is part of a relocation sequence.
// Return the thread-pointer register's encoding.
Fixups.push_back(MCFixup::create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_nofixup));
Triple TT(STI.getTargetTriple());
bool isPPC64 = TT.getArch() == Triple::ppc64 || TT.getArch() == Triple::ppc64le;
return CTX.getRegisterInfo()->getEncodingValue(isPPC64 ? PPC::X13 : PPC::R2);
}
unsigned PPCMCCodeEmitter::getTLSCallEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
// For special TLS calls, we need two fixups; one for the branch target
// (__tls_get_addr), which we create via getDirectBrEncoding as usual,
// and one for the TLSGD or TLSLD symbol, which is emitted here.
const MCOperand &MO = MI.getOperand(OpNo+1);
Fixups.push_back(MCFixup::create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_nofixup));
return getDirectBrEncoding(MI, OpNo, Fixups, STI);
}
unsigned PPCMCCodeEmitter::
get_crbitm_encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(OpNo);
assert((MI.getOpcode() == PPC::MTOCRF || MI.getOpcode() == PPC::MTOCRF8 ||
MI.getOpcode() == PPC::MFOCRF || MI.getOpcode() == PPC::MFOCRF8) &&
(MO.getReg() >= PPC::CR0 && MO.getReg() <= PPC::CR7));
return 0x80 >> CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
}
unsigned PPCMCCodeEmitter::
getMachineOpValue(const MCInst &MI, const MCOperand &MO,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
if (MO.isReg()) {
// MTOCRF/MFOCRF should go through get_crbitm_encoding for the CR operand.
// The GPR operand should come through here though.
assert((MI.getOpcode() != PPC::MTOCRF && MI.getOpcode() != PPC::MTOCRF8 &&
MI.getOpcode() != PPC::MFOCRF && MI.getOpcode() != PPC::MFOCRF8) ||
MO.getReg() < PPC::CR0 || MO.getReg() > PPC::CR7);
return CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
}
assert(MO.isImm() &&
"Relocation required in an instruction that we cannot encode!");
return MO.getImm();
}
#include "PPCGenMCCodeEmitter.inc"