1 //===-- MBlazeMCCodeEmitter.cpp - Convert MBlaze 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 MBlazeMCCodeEmitter class.
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "mccodeemitter"
16 #include "MBlazeInstrInfo.h"
17 #include "llvm/MC/MCCodeEmitter.h"
18 #include "llvm/MC/MCExpr.h"
19 #include "llvm/MC/MCInst.h"
20 #include "llvm/MC/MCSymbol.h"
21 #include "llvm/MC/MCFixup.h"
22 #include "llvm/ADT/Statistic.h"
23 #include "llvm/Support/raw_ostream.h"
26 STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
29 class MBlazeMCCodeEmitter : public MCCodeEmitter {
30 MBlazeMCCodeEmitter(const MBlazeMCCodeEmitter &); // DO NOT IMPLEMENT
31 void operator=(const MBlazeMCCodeEmitter &); // DO NOT IMPLEMENT
32 const TargetMachine &TM;
33 const TargetInstrInfo &TII;
37 MBlazeMCCodeEmitter(TargetMachine &tm, MCContext &ctx)
38 : TM(tm), TII(*TM.getInstrInfo()), Ctx(ctx) {
41 ~MBlazeMCCodeEmitter() {}
43 // getBinaryCodeForInstr - TableGen'erated function for getting the
44 // binary encoding for an instruction.
45 unsigned getBinaryCodeForInstr(const MCInst &MI) const;
47 /// getMachineOpValue - Return binary encoding of operand. If the machine
48 /// operand requires relocation, record the relocation and return zero.
49 unsigned getMachineOpValue(const MCInst &MI,const MCOperand &MO) const;
50 unsigned getMachineOpValue(const MCInst &MI, unsigned OpIdx) const {
51 return getMachineOpValue(MI, MI.getOperand(OpIdx));
54 unsigned getNumFixupKinds() const {
58 static unsigned GetMBlazeRegNum(const MCOperand &MO) {
59 // FIXME: getMBlazeRegisterNumbering() is sufficient?
60 assert(0 && "MBlazeMCCodeEmitter::GetMBlazeRegNum() not yet implemented.");
64 void EmitByte(unsigned char C, unsigned &CurByte, raw_ostream &OS) const {
65 // The MicroBlaze uses a bit reversed format so we need to reverse the
66 // order of the bits. Taken from:
67 // http://graphics.stanford.edu/~seander/bithacks.html
68 C = ((C * 0x80200802ULL) & 0x0884422110ULL) * 0x0101010101ULL >> 32;
74 void EmitRawByte(unsigned char C, unsigned &CurByte, raw_ostream &OS) const {
79 void EmitConstant(uint64_t Val, unsigned Size, unsigned &CurByte,
80 raw_ostream &OS) const {
81 assert(Size <= 8 && "size too big in emit constant");
83 for (unsigned i = 0; i != Size; ++i) {
84 EmitByte(Val & 255, CurByte, OS);
89 void EmitIMM(const MCOperand &imm, unsigned &CurByte, raw_ostream &OS) const;
90 void EmitIMM(const MCInst &MI, unsigned &CurByte, raw_ostream &OS) const;
92 void EmitImmediate(const MCInst &MI, unsigned opNo, bool pcrel,
93 unsigned &CurByte, raw_ostream &OS,
94 SmallVectorImpl<MCFixup> &Fixups) const;
96 void EncodeInstruction(const MCInst &MI, raw_ostream &OS,
97 SmallVectorImpl<MCFixup> &Fixups) const;
100 } // end anonymous namespace
103 MCCodeEmitter *llvm::createMBlazeMCCodeEmitter(const Target &,
106 return new MBlazeMCCodeEmitter(TM, Ctx);
109 /// getMachineOpValue - Return binary encoding of operand. If the machine
110 /// operand requires relocation, record the relocation and return zero.
111 unsigned MBlazeMCCodeEmitter::getMachineOpValue(const MCInst &MI,
112 const MCOperand &MO) const {
114 return MBlazeRegisterInfo::getRegisterNumbering(MO.getReg());
116 return static_cast<unsigned>(MO.getImm());
117 else if (MO.isExpr())
118 return 0; // The relocation has already been recorded at this point.
128 void MBlazeMCCodeEmitter::
129 EmitIMM(const MCOperand &imm, unsigned &CurByte, raw_ostream &OS) const {
130 int32_t val = (int32_t)imm.getImm();
131 if (val > 32767 || val < -32768) {
132 EmitByte(0x0D, CurByte, OS);
133 EmitByte(0x00, CurByte, OS);
134 EmitRawByte((val >> 24) & 0xFF, CurByte, OS);
135 EmitRawByte((val >> 16) & 0xFF, CurByte, OS);
139 void MBlazeMCCodeEmitter::
140 EmitIMM(const MCInst &MI, unsigned &CurByte,raw_ostream &OS) const {
141 switch (MI.getOpcode()) {
146 case MBlaze::BRLID32:
147 EmitByte(0x0D, CurByte, OS);
148 EmitByte(0x00, CurByte, OS);
149 EmitRawByte(0, CurByte, OS);
150 EmitRawByte(0, CurByte, OS);
154 void MBlazeMCCodeEmitter::
155 EmitImmediate(const MCInst &MI, unsigned opNo, bool pcrel, unsigned &CurByte,
156 raw_ostream &OS, SmallVectorImpl<MCFixup> &Fixups) const {
157 assert(MI.getNumOperands()>opNo && "Not enought operands for instruction");
159 MCOperand oper = MI.getOperand(opNo);
162 EmitIMM(oper, CurByte, OS);
163 } else if (oper.isExpr()) {
164 MCFixupKind FixupKind;
165 switch (MI.getOpcode()) {
167 FixupKind = pcrel ? FK_PCRel_2 : FK_Data_2;
168 Fixups.push_back(MCFixup::Create(0,oper.getExpr(),FixupKind));
172 case MBlaze::BRLID32:
173 FixupKind = pcrel ? FK_PCRel_4 : FK_Data_4;
174 Fixups.push_back(MCFixup::Create(0,oper.getExpr(),FixupKind));
182 void MBlazeMCCodeEmitter::
183 EncodeInstruction(const MCInst &MI, raw_ostream &OS,
184 SmallVectorImpl<MCFixup> &Fixups) const {
185 unsigned Opcode = MI.getOpcode();
186 const TargetInstrDesc &Desc = TII.get(Opcode);
187 uint64_t TSFlags = Desc.TSFlags;
188 // Keep track of the current byte being emitted.
189 unsigned CurByte = 0;
191 // Emit an IMM instruction if the instruction we are encoding requires it
192 EmitIMM(MI,CurByte,OS);
194 switch ((TSFlags & MBlazeII::FormMask)) {
196 case MBlazeII::FPseudo:
197 // Pseudo instructions don't get encoded.
200 EmitImmediate(MI, 2, false, CurByte, OS, Fixups);
203 EmitImmediate(MI, 1, false, CurByte, OS, Fixups);
206 EmitImmediate(MI, 1, true, CurByte, OS, Fixups);
209 EmitImmediate(MI, 1, true, CurByte, OS, Fixups);
211 EmitImmediate(MI, 0, true, CurByte, OS, Fixups);
215 ++MCNumEmitted; // Keep track of the # of mi's emitted
216 unsigned Value = getBinaryCodeForInstr(MI);
217 EmitConstant(Value, 4, CurByte, OS);
220 // FIXME: These #defines shouldn't be necessary. Instead, tblgen should
221 // be able to generate code emitter helpers for either variant, like it
222 // does for the AsmWriter.
223 #define MBlazeCodeEmitter MBlazeMCCodeEmitter
224 #define MachineInstr MCInst
225 #include "MBlazeGenCodeEmitter.inc"
226 #undef MBlazeCodeEmitter