1 //===-- ARM/ARMMCCodeEmitter.cpp - Convert ARM code to machine code -------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the ARMMCCodeEmitter class.
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "arm-emitter"
16 #include "ARMAddressingModes.h"
17 #include "ARMInstrInfo.h"
18 #include "llvm/MC/MCCodeEmitter.h"
19 #include "llvm/MC/MCExpr.h"
20 #include "llvm/MC/MCInst.h"
21 #include "llvm/ADT/Statistic.h"
22 #include "llvm/Support/raw_ostream.h"
25 STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
28 class ARMMCCodeEmitter : public MCCodeEmitter {
29 ARMMCCodeEmitter(const ARMMCCodeEmitter &); // DO NOT IMPLEMENT
30 void operator=(const ARMMCCodeEmitter &); // DO NOT IMPLEMENT
31 const TargetMachine &TM;
32 const TargetInstrInfo &TII;
36 ARMMCCodeEmitter(TargetMachine &tm, MCContext &ctx)
37 : TM(tm), TII(*TM.getInstrInfo()), Ctx(ctx) {
40 ~ARMMCCodeEmitter() {}
42 unsigned getMachineSoImmOpValue(unsigned SoImm) const;
44 // getBinaryCodeForInstr - TableGen'erated function for getting the
45 // binary encoding for an instruction.
46 unsigned getBinaryCodeForInstr(const MCInst &MI) const;
48 /// getMachineOpValue - Return binary encoding of operand. If the machine
49 /// operand requires relocation, record the relocation and return zero.
50 unsigned getMachineOpValue(const MCInst &MI,const MCOperand &MO) const;
51 unsigned getMachineOpValue(const MCInst &MI, unsigned OpIdx) const {
52 return getMachineOpValue(MI, MI.getOperand(OpIdx));
55 unsigned getNumFixupKinds() const {
56 assert(0 && "ARMMCCodeEmitter::getNumFixupKinds() not yet implemented.");
60 const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const {
61 static MCFixupKindInfo rtn;
62 assert(0 && "ARMMCCodeEmitter::getFixupKindInfo() not yet implemented.");
66 void EmitByte(unsigned char C, unsigned &CurByte, raw_ostream &OS) const {
71 void EmitConstant(uint64_t Val, unsigned Size, unsigned &CurByte,
72 raw_ostream &OS) const {
73 // Output the constant in little endian byte order.
74 for (unsigned i = 0; i != Size; ++i) {
75 EmitByte(Val & 255, CurByte, OS);
80 void EmitImmediate(const MCOperand &Disp,
81 unsigned ImmSize, MCFixupKind FixupKind,
82 unsigned &CurByte, raw_ostream &OS,
83 SmallVectorImpl<MCFixup> &Fixups,
84 int ImmOffset = 0) const;
86 void EncodeInstruction(const MCInst &MI, raw_ostream &OS,
87 SmallVectorImpl<MCFixup> &Fixups) const;
90 } // end anonymous namespace
92 unsigned ARMMCCodeEmitter::getMachineSoImmOpValue(unsigned SoImm) const {
93 int SoImmVal = ARM_AM::getSOImmVal(SoImm);
94 assert(SoImmVal != -1 && "Not a valid so_imm value!");
97 unsigned Binary = (ARM_AM::getSOImmValRot((unsigned)SoImmVal) >> 1)
98 << ARMII::SoRotImmShift;
101 Binary |= ARM_AM::getSOImmValImm((unsigned)SoImmVal);
105 MCCodeEmitter *llvm::createARMMCCodeEmitter(const Target &,
108 return new ARMMCCodeEmitter(TM, Ctx);
111 void ARMMCCodeEmitter::
112 EmitImmediate(const MCOperand &DispOp, unsigned Size, MCFixupKind FixupKind,
113 unsigned &CurByte, raw_ostream &OS,
114 SmallVectorImpl<MCFixup> &Fixups, int ImmOffset) const {
115 assert(0 && "ARMMCCodeEmitter::EmitImmediate() not yet implemented.");
118 /// getMachineOpValue - Return binary encoding of operand. If the machine
119 /// operand requires relocation, record the relocation and return zero.
120 unsigned ARMMCCodeEmitter::getMachineOpValue(const MCInst &MI,
121 const MCOperand &MO) const {
123 return getARMRegisterNumbering(MO.getReg());
124 else if (MO.isImm()) {
125 return static_cast<unsigned>(MO.getImm());
135 void ARMMCCodeEmitter::
136 EncodeInstruction(const MCInst &MI, raw_ostream &OS,
137 SmallVectorImpl<MCFixup> &Fixups) const {
138 unsigned Opcode = MI.getOpcode();
139 const TargetInstrDesc &Desc = TII.get(Opcode);
140 uint64_t TSFlags = Desc.TSFlags;
141 // Keep track of the current byte being emitted.
142 unsigned CurByte = 0;
144 // Pseudo instructions don't get encoded.
145 if ((TSFlags & ARMII::FormMask) == ARMII::Pseudo)
148 ++MCNumEmitted; // Keep track of the # of mi's emitted
149 // FIXME: TableGen doesn't deal well with operands that expand to multiple
150 // machine instruction operands, so for now we'll fix those up here.
151 // Similarly, operands that are encoded as other than their literal
153 unsigned Value = getBinaryCodeForInstr(MI);
163 if (MI.getOperand(5).getReg() == ARM::CPSR)
164 Value |= 1 << ARMII::S_BitShift;
165 // The shifted immediate value.
166 Value |= getMachineSoImmOpValue((unsigned)MI.getOperand(2).getImm());
175 if (MI.getOperand(7).getReg() == ARM::CPSR)
176 Value |= 1 << ARMII::S_BitShift;
177 // The so_reg operand needs the shift ammount encoded.
178 unsigned ShVal = MI.getOperand(4).getImm();
179 unsigned ShType = ARM_AM::getShiftOpcEncoding(ARM_AM::getSORegShOp(ShVal));
180 unsigned ShAmt = ARM_AM::getSORegOffset(ShVal);
181 Value |= ShType << ARMII::ShiftTypeShift;
182 Value |= ShAmt << ARMII::ShiftShift;
186 EmitConstant(Value, 4, CurByte, OS);
189 // FIXME: These #defines shouldn't be necessary. Instead, tblgen should
190 // be able to generate code emitter helpers for either variant, like it
191 // does for the AsmWriter.
192 #define ARMCodeEmitter ARMMCCodeEmitter
193 #define MachineInstr MCInst
194 #include "ARMGenCodeEmitter.inc"
195 #undef ARMCodeEmitter