1 //===-- MipsMCInstLower.cpp - Convert Mips MachineInstr to MCInst ---------===//
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 contains code to lower Mips MachineInstrs to their corresponding
13 //===----------------------------------------------------------------------===//
15 #include "MipsAsmPrinter.h"
16 #include "MipsInstrInfo.h"
17 #include "MipsMCInstLower.h"
18 #include "MCTargetDesc/MipsBaseInfo.h"
19 #include "llvm/CodeGen/MachineFunction.h"
20 #include "llvm/CodeGen/MachineInstr.h"
21 #include "llvm/CodeGen/MachineOperand.h"
22 #include "llvm/MC/MCContext.h"
23 #include "llvm/MC/MCExpr.h"
24 #include "llvm/MC/MCInst.h"
25 #include "llvm/Target/Mangler.h"
29 MipsMCInstLower::MipsMCInstLower(Mangler *mang, const MachineFunction &mf,
30 MipsAsmPrinter &asmprinter)
31 : Ctx(mf.getContext()), Mang(mang), AsmPrinter(asmprinter) {}
33 MCOperand MipsMCInstLower::LowerSymbolOperand(const MachineOperand &MO,
34 MachineOperandType MOTy,
35 unsigned Offset) const {
36 MCSymbolRefExpr::VariantKind Kind;
37 const MCSymbol *Symbol;
39 switch(MO.getTargetFlags()) {
40 default: assert(0 && "Invalid target flag!");
41 case MipsII::MO_NO_FLAG: Kind = MCSymbolRefExpr::VK_None; break;
42 case MipsII::MO_GPREL: Kind = MCSymbolRefExpr::VK_Mips_GPREL; break;
43 case MipsII::MO_GOT_CALL: Kind = MCSymbolRefExpr::VK_Mips_GOT_CALL; break;
44 case MipsII::MO_GOT16: Kind = MCSymbolRefExpr::VK_Mips_GOT16; break;
45 case MipsII::MO_GOT: Kind = MCSymbolRefExpr::VK_Mips_GOT; break;
46 case MipsII::MO_ABS_HI: Kind = MCSymbolRefExpr::VK_Mips_ABS_HI; break;
47 case MipsII::MO_ABS_LO: Kind = MCSymbolRefExpr::VK_Mips_ABS_LO; break;
48 case MipsII::MO_TLSGD: Kind = MCSymbolRefExpr::VK_Mips_TLSGD; break;
49 case MipsII::MO_GOTTPREL: Kind = MCSymbolRefExpr::VK_Mips_GOTTPREL; break;
50 case MipsII::MO_TPREL_HI: Kind = MCSymbolRefExpr::VK_Mips_TPREL_HI; break;
51 case MipsII::MO_TPREL_LO: Kind = MCSymbolRefExpr::VK_Mips_TPREL_LO; break;
52 case MipsII::MO_GPOFF_HI: Kind = MCSymbolRefExpr::VK_Mips_GPOFF_HI; break;
53 case MipsII::MO_GPOFF_LO: Kind = MCSymbolRefExpr::VK_Mips_GPOFF_LO; break;
54 case MipsII::MO_GOT_DISP: Kind = MCSymbolRefExpr::VK_Mips_GOT_DISP; break;
55 case MipsII::MO_GOT_PAGE: Kind = MCSymbolRefExpr::VK_Mips_GOT_PAGE; break;
56 case MipsII::MO_GOT_OFST: Kind = MCSymbolRefExpr::VK_Mips_GOT_OFST; break;
60 case MachineOperand::MO_MachineBasicBlock:
61 Symbol = MO.getMBB()->getSymbol();
64 case MachineOperand::MO_GlobalAddress:
65 Symbol = Mang->getSymbol(MO.getGlobal());
68 case MachineOperand::MO_BlockAddress:
69 Symbol = AsmPrinter.GetBlockAddressSymbol(MO.getBlockAddress());
72 case MachineOperand::MO_ExternalSymbol:
73 Symbol = AsmPrinter.GetExternalSymbolSymbol(MO.getSymbolName());
76 case MachineOperand::MO_JumpTableIndex:
77 Symbol = AsmPrinter.GetJTISymbol(MO.getIndex());
80 case MachineOperand::MO_ConstantPoolIndex:
81 Symbol = AsmPrinter.GetCPISymbol(MO.getIndex());
83 Offset += MO.getOffset();
87 llvm_unreachable("<unknown operand type>");
90 const MCSymbolRefExpr *MCSym = MCSymbolRefExpr::Create(Symbol, Kind, Ctx);
93 return MCOperand::CreateExpr(MCSym);
95 // Assume offset is never negative.
98 const MCConstantExpr *OffsetExpr = MCConstantExpr::Create(Offset, Ctx);
99 const MCBinaryExpr *AddExpr = MCBinaryExpr::CreateAdd(MCSym, OffsetExpr, Ctx);
100 return MCOperand::CreateExpr(AddExpr);
103 // Lower ".cpload $reg" to
104 // "lui $gp, %hi(_gp_disp)"
105 // "addiu $gp, $gp, %lo(_gp_disp)"
106 // "addu $gp. $gp, $reg"
107 void MipsMCInstLower::LowerCPLOAD(const MachineInstr *MI,
108 SmallVector<MCInst, 4>& MCInsts) {
109 MCInst Lui, Addiu, Addu;
110 StringRef SymName("_gp_disp");
111 const MCSymbol *Symbol = Ctx.GetOrCreateSymbol(SymName);
112 const MCSymbolRefExpr *MCSym;
114 // lui $gp, %hi(_gp_disp)
115 Lui.setOpcode(Mips::LUi);
116 Lui.addOperand(MCOperand::CreateReg(Mips::GP));
117 MCSym = MCSymbolRefExpr::Create(Symbol, MCSymbolRefExpr::VK_Mips_ABS_HI, Ctx);
118 Lui.addOperand(MCOperand::CreateExpr(MCSym));
119 MCInsts.push_back(Lui);
121 // addiu $gp, $gp, %lo(_gp_disp)
122 Addiu.setOpcode(Mips::ADDiu);
123 Addiu.addOperand(MCOperand::CreateReg(Mips::GP));
124 Addiu.addOperand(MCOperand::CreateReg(Mips::GP));
125 MCSym = MCSymbolRefExpr::Create(Symbol, MCSymbolRefExpr::VK_Mips_ABS_LO, Ctx);
126 Addiu.addOperand(MCOperand::CreateExpr(MCSym));
127 MCInsts.push_back(Addiu);
129 // addu $gp. $gp, $reg
130 Addu.setOpcode(Mips::ADDu);
131 Addu.addOperand(MCOperand::CreateReg(Mips::GP));
132 Addu.addOperand(MCOperand::CreateReg(Mips::GP));
133 const MachineOperand &MO = MI->getOperand(0);
134 assert(MO.isReg() && "CPLOAD's operand must be a register.");
135 Addu.addOperand(MCOperand::CreateReg(MO.getReg()));
136 MCInsts.push_back(Addu);
139 // Lower ".cprestore offset" to "sw $gp, offset($sp)".
140 void MipsMCInstLower::LowerCPRESTORE(const MachineInstr *MI,
141 SmallVector<MCInst, 4>& MCInsts) {
142 const MachineOperand &MO = MI->getOperand(0);
143 assert(MO.isImm() && "CPRESTORE's operand must be an immediate.");
144 unsigned Offset = MO.getImm(), Reg = Mips::SP;
147 if (Offset >= 0x8000) {
148 unsigned Hi = (Offset >> 16) + ((Offset & 0x8000) != 0);
155 MCInsts[0].setOpcode(Mips::LUi);
156 MCInsts[0].addOperand(MCOperand::CreateReg(Mips::AT));
157 MCInsts[0].addOperand(MCOperand::CreateImm(Hi));
158 MCInsts[1].setOpcode(Mips::ADDu);
159 MCInsts[1].addOperand(MCOperand::CreateReg(Mips::AT));
160 MCInsts[1].addOperand(MCOperand::CreateReg(Mips::AT));
161 MCInsts[1].addOperand(MCOperand::CreateReg(Mips::SP));
164 Sw.setOpcode(Mips::SW);
165 Sw.addOperand(MCOperand::CreateReg(Mips::GP));
166 Sw.addOperand(MCOperand::CreateReg(Reg));
167 Sw.addOperand(MCOperand::CreateImm(Offset));
168 MCInsts.push_back(Sw);
171 MCOperand MipsMCInstLower::LowerOperand(const MachineOperand& MO,
172 unsigned offset) const {
173 MachineOperandType MOTy = MO.getType();
177 assert(0 && "unknown operand type");
179 case MachineOperand::MO_Register:
180 // Ignore all implicit register operands.
181 if (MO.isImplicit()) break;
182 return MCOperand::CreateReg(MO.getReg());
183 case MachineOperand::MO_Immediate:
184 return MCOperand::CreateImm(MO.getImm() + offset);
185 case MachineOperand::MO_MachineBasicBlock:
186 case MachineOperand::MO_GlobalAddress:
187 case MachineOperand::MO_ExternalSymbol:
188 case MachineOperand::MO_JumpTableIndex:
189 case MachineOperand::MO_ConstantPoolIndex:
190 case MachineOperand::MO_BlockAddress:
191 return LowerSymbolOperand(MO, MOTy, offset);
197 void MipsMCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
198 OutMI.setOpcode(MI->getOpcode());
200 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
201 const MachineOperand &MO = MI->getOperand(i);
202 MCOperand MCOp = LowerOperand(MO);
205 OutMI.addOperand(MCOp);
209 void MipsMCInstLower::LowerUnalignedLoadStore(const MachineInstr *MI,
212 unsigned Opc = MI->getOpcode();
213 MCInst instr1, instr2, instr3, move;
215 bool two_instructions = false;
217 assert(MI->getNumOperands() == 3);
218 assert(MI->getOperand(0).isReg());
219 assert(MI->getOperand(1).isReg());
221 MCOperand target = LowerOperand(MI->getOperand(0));
222 MCOperand base = LowerOperand(MI->getOperand(1));
223 MCOperand atReg = MCOperand::CreateReg(Mips::AT);
224 MCOperand zeroReg = MCOperand::CreateReg(Mips::ZERO);
226 MachineOperand unloweredName = MI->getOperand(2);
227 MCOperand name = LowerOperand(unloweredName);
229 move.setOpcode(Mips::ADDu);
230 move.addOperand(target);
231 move.addOperand(atReg);
232 move.addOperand(zeroReg);
236 // FIXME: only works for little endian right now
237 MCOperand adj_name = LowerOperand(unloweredName, 3);
238 if (base.getReg() == (target.getReg())) {
239 instr1.setOpcode(Mips::LWL);
240 instr1.addOperand(atReg);
241 instr1.addOperand(base);
242 instr1.addOperand(adj_name);
243 instr2.setOpcode(Mips::LWR);
244 instr2.addOperand(atReg);
245 instr2.addOperand(base);
246 instr2.addOperand(name);
249 two_instructions = true;
250 instr1.setOpcode(Mips::LWL);
251 instr1.addOperand(target);
252 instr1.addOperand(base);
253 instr1.addOperand(adj_name);
254 instr2.setOpcode(Mips::LWR);
255 instr2.addOperand(target);
256 instr2.addOperand(base);
257 instr2.addOperand(name);
262 // FIXME: only works for little endian right now
263 MCOperand adj_name = LowerOperand(unloweredName, 1);
264 instr1.setOpcode(Mips::LBu);
265 instr1.addOperand(atReg);
266 instr1.addOperand(base);
267 instr1.addOperand(adj_name);
268 instr2.setOpcode(Mips::LBu);
269 instr2.addOperand(target);
270 instr2.addOperand(base);
271 instr2.addOperand(name);
272 instr3.setOpcode(Mips::INS);
273 instr3.addOperand(target);
274 instr3.addOperand(atReg);
275 instr3.addOperand(MCOperand::CreateImm(0x8));
276 instr3.addOperand(MCOperand::CreateImm(0x18));
281 // FIXME: only works for little endian right now
282 assert (base.getReg() != target.getReg());
283 two_instructions = true;
284 MCOperand adj_name = LowerOperand(unloweredName, 3);
285 instr1.setOpcode(Mips::SWL);
286 instr1.addOperand(target);
287 instr1.addOperand(base);
288 instr1.addOperand(adj_name);
289 instr2.setOpcode(Mips::SWR);
290 instr2.addOperand(target);
291 instr2.addOperand(base);
292 instr2.addOperand(name);
296 MCOperand adj_name = LowerOperand(unloweredName, 1);
297 instr1.setOpcode(Mips::SB);
298 instr1.addOperand(target);
299 instr1.addOperand(base);
300 instr1.addOperand(name);
301 instr2.setOpcode(Mips::SRL);
302 instr2.addOperand(atReg);
303 instr2.addOperand(target);
304 instr2.addOperand(MCOperand::CreateImm(8));
305 instr3.setOpcode(Mips::SB);
306 instr3.addOperand(atReg);
307 instr3.addOperand(base);
308 instr3.addOperand(adj_name);
312 // FIXME: need to add others
313 assert(0 && "unaligned instruction not processed");
316 MCInsts.push_back(instr1);
317 MCInsts.push_back(instr2);
318 if (!two_instructions) MCInsts.push_back(instr3);