llvm-6502/lib/Target/PowerPC/PPCMCCodeEmitter.cpp
Daniel Dunbar 2761fc4270 MC: Move target specific fixup info descriptors to TargetAsmBackend instead of
the MCCodeEmitter, which seems like a better organization.
 - Also, cleaned up some magic constants while in the area.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121953 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-16 03:20:06 +00:00

196 lines
7.5 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.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "mccodeemitter"
#include "PPC.h"
#include "PPCRegisterInfo.h"
#include "PPCFixupKinds.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCInst.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/ErrorHandling.h"
using namespace llvm;
STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
namespace {
class PPCMCCodeEmitter : public MCCodeEmitter {
PPCMCCodeEmitter(const PPCMCCodeEmitter &); // DO NOT IMPLEMENT
void operator=(const PPCMCCodeEmitter &); // DO NOT IMPLEMENT
const TargetMachine &TM;
MCContext &Ctx;
public:
PPCMCCodeEmitter(TargetMachine &tm, MCContext &ctx)
: TM(tm), Ctx(ctx) {
}
~PPCMCCodeEmitter() {}
unsigned getDirectBrEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getCondBrEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getHA16Encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getLO16Encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getMemRIEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned getMemRIXEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) const;
unsigned get_crbitm_encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) 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;
// getBinaryCodeForInstr - TableGen'erated function for getting the
// binary encoding for an instruction.
unsigned getBinaryCodeForInstr(const MCInst &MI,
SmallVectorImpl<MCFixup> &Fixups) const;
void EncodeInstruction(const MCInst &MI, raw_ostream &OS,
SmallVectorImpl<MCFixup> &Fixups) const {
unsigned Bits = getBinaryCodeForInstr(MI, Fixups);
// Output the constant in big endian byte order.
for (unsigned i = 0; i != 4; ++i) {
OS << (char)(Bits >> 24);
Bits <<= 8;
}
++MCNumEmitted; // Keep track of the # of mi's emitted.
}
};
} // end anonymous namespace
MCCodeEmitter *llvm::createPPCMCCodeEmitter(const Target &, TargetMachine &TM,
MCContext &Ctx) {
return new PPCMCCodeEmitter(TM, Ctx);
}
unsigned PPCMCCodeEmitter::
getDirectBrEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isReg() || MO.isImm()) return getMachineOpValue(MI, MO, Fixups);
// 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 {
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isReg() || MO.isImm()) return getMachineOpValue(MI, MO, Fixups);
// Add a fixup for the branch target.
Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_brcond14));
return 0;
}
unsigned PPCMCCodeEmitter::getHA16Encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isReg() || MO.isImm()) return getMachineOpValue(MI, MO, Fixups);
// Add a fixup for the branch target.
Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_ha16));
return 0;
}
unsigned PPCMCCodeEmitter::getLO16Encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isReg() || MO.isImm()) return getMachineOpValue(MI, MO, Fixups);
// Add a fixup for the branch target.
Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_lo16));
return 0;
}
unsigned PPCMCCodeEmitter::getMemRIEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) 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) << 16;
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isImm())
return (getMachineOpValue(MI, MO, Fixups) & 0xFFFF) | RegBits;
// Add a fixup for the displacement field.
Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_lo16));
return RegBits;
}
unsigned PPCMCCodeEmitter::getMemRIXEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) 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) << 14;
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isImm())
return (getMachineOpValue(MI, MO, Fixups) & 0x3FFF) | RegBits;
// Add a fixup for the branch target.
Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_lo14));
return RegBits;
}
unsigned PPCMCCodeEmitter::
get_crbitm_encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups) const {
const MCOperand &MO = MI.getOperand(OpNo);
assert((MI.getOpcode() == PPC::MTCRF || MI.getOpcode() == PPC::MFOCRF) &&
(MO.getReg() >= PPC::CR0 && MO.getReg() <= PPC::CR7));
return 0x80 >> PPCRegisterInfo::getRegisterNumbering(MO.getReg());
}
unsigned PPCMCCodeEmitter::
getMachineOpValue(const MCInst &MI, const MCOperand &MO,
SmallVectorImpl<MCFixup> &Fixups) const {
if (MO.isReg()) {
// MTCRF/MFOCRF should go through get_crbitm_encoding for the CR operand.
// The GPR operand should come through here though.
assert((MI.getOpcode() != PPC::MTCRF && MI.getOpcode() != PPC::MFOCRF) ||
MO.getReg() < PPC::CR0 || MO.getReg() > PPC::CR7);
return PPCRegisterInfo::getRegisterNumbering(MO.getReg());
}
assert(MO.isImm() &&
"Relocation required in an instruction that we cannot encode!");
return MO.getImm();
}
#include "PPCGenMCCodeEmitter.inc"