1 //===-- MipsInstPrinter.cpp - Convert Mips MCInst to assembly syntax ------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This class prints an Mips MCInst to a .s file.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "MipsInstPrinter.h"
14 #include "MipsInstrInfo.h"
15 #include "MipsMCExpr.h"
16 #include "llvm/ADT/StringExtras.h"
17 #include "llvm/MC/MCExpr.h"
18 #include "llvm/MC/MCInst.h"
19 #include "llvm/MC/MCInstrInfo.h"
20 #include "llvm/MC/MCSymbol.h"
21 #include "llvm/Support/ErrorHandling.h"
22 #include "llvm/Support/raw_ostream.h"
23 using namespace llvm;
24
25 #define DEBUG_TYPE "asm-printer"
26
27 #define PRINT_ALIAS_INSTR
28 #include "MipsGenAsmWriter.inc"
29
30 template<unsigned R>
isReg(const MCInst & MI,unsigned OpNo)31 static bool isReg(const MCInst &MI, unsigned OpNo) {
32 assert(MI.getOperand(OpNo).isReg() && "Register operand expected.");
33 return MI.getOperand(OpNo).getReg() == R;
34 }
35
MipsFCCToString(Mips::CondCode CC)36 const char* Mips::MipsFCCToString(Mips::CondCode CC) {
37 switch (CC) {
38 case FCOND_F:
39 case FCOND_T: return "f";
40 case FCOND_UN:
41 case FCOND_OR: return "un";
42 case FCOND_OEQ:
43 case FCOND_UNE: return "eq";
44 case FCOND_UEQ:
45 case FCOND_ONE: return "ueq";
46 case FCOND_OLT:
47 case FCOND_UGE: return "olt";
48 case FCOND_ULT:
49 case FCOND_OGE: return "ult";
50 case FCOND_OLE:
51 case FCOND_UGT: return "ole";
52 case FCOND_ULE:
53 case FCOND_OGT: return "ule";
54 case FCOND_SF:
55 case FCOND_ST: return "sf";
56 case FCOND_NGLE:
57 case FCOND_GLE: return "ngle";
58 case FCOND_SEQ:
59 case FCOND_SNE: return "seq";
60 case FCOND_NGL:
61 case FCOND_GL: return "ngl";
62 case FCOND_LT:
63 case FCOND_NLT: return "lt";
64 case FCOND_NGE:
65 case FCOND_GE: return "nge";
66 case FCOND_LE:
67 case FCOND_NLE: return "le";
68 case FCOND_NGT:
69 case FCOND_GT: return "ngt";
70 }
71 llvm_unreachable("Impossible condition code!");
72 }
73
printRegName(raw_ostream & OS,MCRegister Reg) const74 void MipsInstPrinter::printRegName(raw_ostream &OS, MCRegister Reg) const {
75 OS << markup("<reg:") << '$' << StringRef(getRegisterName(Reg)).lower()
76 << markup(">");
77 }
78
printInst(const MCInst * MI,uint64_t Address,StringRef Annot,const MCSubtargetInfo & STI,raw_ostream & O)79 void MipsInstPrinter::printInst(const MCInst *MI, uint64_t Address,
80 StringRef Annot, const MCSubtargetInfo &STI,
81 raw_ostream &O) {
82 switch (MI->getOpcode()) {
83 default:
84 break;
85 case Mips::RDHWR:
86 case Mips::RDHWR64:
87 O << "\t.set\tpush\n";
88 O << "\t.set\tmips32r2\n";
89 break;
90 case Mips::Save16:
91 O << "\tsave\t";
92 printSaveRestore(MI, STI, O);
93 O << " # 16 bit inst\n";
94 return;
95 case Mips::SaveX16:
96 O << "\tsave\t";
97 printSaveRestore(MI, STI, O);
98 O << "\n";
99 return;
100 case Mips::Restore16:
101 O << "\trestore\t";
102 printSaveRestore(MI, STI, O);
103 O << " # 16 bit inst\n";
104 return;
105 case Mips::RestoreX16:
106 O << "\trestore\t";
107 printSaveRestore(MI, STI, O);
108 O << "\n";
109 return;
110 }
111
112 // Try to print any aliases first.
113 if (!printAliasInstr(MI, Address, STI, O) &&
114 !printAlias(*MI, Address, STI, O))
115 printInstruction(MI, Address, STI, O);
116 printAnnotation(O, Annot);
117
118 switch (MI->getOpcode()) {
119 default:
120 break;
121 case Mips::RDHWR:
122 case Mips::RDHWR64:
123 O << "\n\t.set\tpop";
124 }
125 }
126
printOperand(const MCInst * MI,unsigned OpNo,const MCSubtargetInfo & STI,raw_ostream & O)127 void MipsInstPrinter::printOperand(const MCInst *MI, unsigned OpNo,
128 const MCSubtargetInfo &STI, raw_ostream &O) {
129 const MCOperand &Op = MI->getOperand(OpNo);
130 if (Op.isReg()) {
131 printRegName(O, Op.getReg());
132 return;
133 }
134
135 if (Op.isImm()) {
136 O << markup("<imm:") << formatImm(Op.getImm()) << markup(">");
137 return;
138 }
139
140 assert(Op.isExpr() && "unknown operand kind in printOperand");
141 Op.getExpr()->print(O, &MAI, true);
142 }
143
printJumpOperand(const MCInst * MI,unsigned OpNo,const MCSubtargetInfo & STI,raw_ostream & O)144 void MipsInstPrinter::printJumpOperand(const MCInst *MI, unsigned OpNo,
145 const MCSubtargetInfo &STI,
146 raw_ostream &O) {
147 const MCOperand &Op = MI->getOperand(OpNo);
148 if (!Op.isImm())
149 return printOperand(MI, OpNo, STI, O);
150
151 if (PrintBranchImmAsAddress)
152 O << markup("<imm:") << formatHex(Op.getImm()) << markup(">");
153 else
154 O << markup("<imm:") << formatImm(Op.getImm()) << markup(">");
155 }
156
printBranchOperand(const MCInst * MI,uint64_t Address,unsigned OpNo,const MCSubtargetInfo & STI,raw_ostream & O)157 void MipsInstPrinter::printBranchOperand(const MCInst *MI, uint64_t Address,
158 unsigned OpNo,
159 const MCSubtargetInfo &STI,
160 raw_ostream &O) {
161 const MCOperand &Op = MI->getOperand(OpNo);
162 if (!Op.isImm())
163 return printOperand(MI, OpNo, STI, O);
164
165 if (PrintBranchImmAsAddress) {
166 uint64_t Target = Address + Op.getImm();
167 if (STI.hasFeature(Mips::FeatureMips32))
168 Target &= 0xffffffff;
169 else if (STI.hasFeature(Mips::FeatureMips16))
170 Target &= 0xffff;
171 O << markup("<imm:") << formatHex(Target) << markup(">");
172 } else {
173 O << markup("<imm:") << formatImm(Op.getImm()) << markup(">");
174 }
175 }
176
177 template <unsigned Bits, unsigned Offset>
printUImm(const MCInst * MI,int opNum,const MCSubtargetInfo & STI,raw_ostream & O)178 void MipsInstPrinter::printUImm(const MCInst *MI, int opNum,
179 const MCSubtargetInfo &STI, raw_ostream &O) {
180 const MCOperand &MO = MI->getOperand(opNum);
181 if (MO.isImm()) {
182 uint64_t Imm = MO.getImm();
183 Imm -= Offset;
184 Imm &= (1 << Bits) - 1;
185 Imm += Offset;
186 O << markup("<imm:") << formatImm(Imm) << markup(">");
187 return;
188 }
189
190 printOperand(MI, opNum, STI, O);
191 }
192
printMemOperand(const MCInst * MI,int opNum,const MCSubtargetInfo & STI,raw_ostream & O)193 void MipsInstPrinter::printMemOperand(const MCInst *MI, int opNum,
194 const MCSubtargetInfo &STI,
195 raw_ostream &O) {
196 // Load/Store memory operands -- imm($reg)
197 // If PIC target the target is loaded as the
198 // pattern lw $25,%call16($28)
199
200 // opNum can be invalid if instruction had reglist as operand.
201 // MemOperand is always last operand of instruction (base + offset).
202 switch (MI->getOpcode()) {
203 default:
204 break;
205 case Mips::SWM32_MM:
206 case Mips::LWM32_MM:
207 case Mips::SWM16_MM:
208 case Mips::SWM16_MMR6:
209 case Mips::LWM16_MM:
210 case Mips::LWM16_MMR6:
211 opNum = MI->getNumOperands() - 2;
212 break;
213 }
214
215 O << markup("<mem:");
216 printOperand(MI, opNum + 1, STI, O);
217 O << "(";
218 printOperand(MI, opNum, STI, O);
219 O << ")";
220 O << markup(">");
221 }
222
printMemOperandEA(const MCInst * MI,int opNum,const MCSubtargetInfo & STI,raw_ostream & O)223 void MipsInstPrinter::printMemOperandEA(const MCInst *MI, int opNum,
224 const MCSubtargetInfo &STI,
225 raw_ostream &O) {
226 // when using stack locations for not load/store instructions
227 // print the same way as all normal 3 operand instructions.
228 printOperand(MI, opNum, STI, O);
229 O << ", ";
230 printOperand(MI, opNum + 1, STI, O);
231 }
232
printFCCOperand(const MCInst * MI,int opNum,const MCSubtargetInfo &,raw_ostream & O)233 void MipsInstPrinter::printFCCOperand(const MCInst *MI, int opNum,
234 const MCSubtargetInfo & /* STI */,
235 raw_ostream &O) {
236 const MCOperand &MO = MI->getOperand(opNum);
237 O << MipsFCCToString((Mips::CondCode)MO.getImm());
238 }
239
240 void MipsInstPrinter::
printSHFMask(const MCInst * MI,int opNum,raw_ostream & O)241 printSHFMask(const MCInst *MI, int opNum, raw_ostream &O) {
242 llvm_unreachable("TODO");
243 }
244
printAlias(const char * Str,const MCInst & MI,uint64_t Address,unsigned OpNo,const MCSubtargetInfo & STI,raw_ostream & OS,bool IsBranch)245 bool MipsInstPrinter::printAlias(const char *Str, const MCInst &MI,
246 uint64_t Address, unsigned OpNo,
247 const MCSubtargetInfo &STI, raw_ostream &OS,
248 bool IsBranch) {
249 OS << "\t" << Str << "\t";
250 if (IsBranch)
251 printBranchOperand(&MI, Address, OpNo, STI, OS);
252 else
253 printOperand(&MI, OpNo, STI, OS);
254 return true;
255 }
256
printAlias(const char * Str,const MCInst & MI,uint64_t Address,unsigned OpNo0,unsigned OpNo1,const MCSubtargetInfo & STI,raw_ostream & OS,bool IsBranch)257 bool MipsInstPrinter::printAlias(const char *Str, const MCInst &MI,
258 uint64_t Address, unsigned OpNo0,
259 unsigned OpNo1, const MCSubtargetInfo &STI,
260 raw_ostream &OS, bool IsBranch) {
261 printAlias(Str, MI, Address, OpNo0, STI, OS, IsBranch);
262 OS << ", ";
263 if (IsBranch)
264 printBranchOperand(&MI, Address, OpNo1, STI, OS);
265 else
266 printOperand(&MI, OpNo1, STI, OS);
267 return true;
268 }
269
printAlias(const MCInst & MI,uint64_t Address,const MCSubtargetInfo & STI,raw_ostream & OS)270 bool MipsInstPrinter::printAlias(const MCInst &MI, uint64_t Address,
271 const MCSubtargetInfo &STI, raw_ostream &OS) {
272 switch (MI.getOpcode()) {
273 case Mips::BEQ:
274 case Mips::BEQ_MM:
275 // beq $zero, $zero, $L2 => b $L2
276 // beq $r0, $zero, $L2 => beqz $r0, $L2
277 return (isReg<Mips::ZERO>(MI, 0) && isReg<Mips::ZERO>(MI, 1) &&
278 printAlias("b", MI, Address, 2, STI, OS, true)) ||
279 (isReg<Mips::ZERO>(MI, 1) &&
280 printAlias("beqz", MI, Address, 0, 2, STI, OS, true));
281 case Mips::BEQ64:
282 // beq $r0, $zero, $L2 => beqz $r0, $L2
283 return isReg<Mips::ZERO_64>(MI, 1) &&
284 printAlias("beqz", MI, Address, 0, 2, STI, OS, true);
285 case Mips::BNE:
286 case Mips::BNE_MM:
287 // bne $r0, $zero, $L2 => bnez $r0, $L2
288 return isReg<Mips::ZERO>(MI, 1) &&
289 printAlias("bnez", MI, Address, 0, 2, STI, OS, true);
290 case Mips::BNE64:
291 // bne $r0, $zero, $L2 => bnez $r0, $L2
292 return isReg<Mips::ZERO_64>(MI, 1) &&
293 printAlias("bnez", MI, Address, 0, 2, STI, OS, true);
294 case Mips::BGEZAL:
295 // bgezal $zero, $L1 => bal $L1
296 return isReg<Mips::ZERO>(MI, 0) &&
297 printAlias("bal", MI, Address, 1, STI, OS, true);
298 case Mips::BC1T:
299 // bc1t $fcc0, $L1 => bc1t $L1
300 return isReg<Mips::FCC0>(MI, 0) &&
301 printAlias("bc1t", MI, Address, 1, STI, OS, true);
302 case Mips::BC1F:
303 // bc1f $fcc0, $L1 => bc1f $L1
304 return isReg<Mips::FCC0>(MI, 0) &&
305 printAlias("bc1f", MI, Address, 1, STI, OS, true);
306 case Mips::JALR:
307 // jalr $zero, $r1 => jr $r1
308 // jalr $ra, $r1 => jalr $r1
309 return (isReg<Mips::ZERO>(MI, 0) &&
310 printAlias("jr", MI, Address, 1, STI, OS)) ||
311 (isReg<Mips::RA>(MI, 0) &&
312 printAlias("jalr", MI, Address, 1, STI, OS));
313 case Mips::JALR64:
314 // jalr $zero, $r1 => jr $r1
315 // jalr $ra, $r1 => jalr $r1
316 return (isReg<Mips::ZERO_64>(MI, 0) &&
317 printAlias("jr", MI, Address, 1, STI, OS)) ||
318 (isReg<Mips::RA_64>(MI, 0) &&
319 printAlias("jalr", MI, Address, 1, STI, OS));
320 case Mips::NOR:
321 case Mips::NOR_MM:
322 case Mips::NOR_MMR6:
323 // nor $r0, $r1, $zero => not $r0, $r1
324 return isReg<Mips::ZERO>(MI, 2) &&
325 printAlias("not", MI, Address, 0, 1, STI, OS);
326 case Mips::NOR64:
327 // nor $r0, $r1, $zero => not $r0, $r1
328 return isReg<Mips::ZERO_64>(MI, 2) &&
329 printAlias("not", MI, Address, 0, 1, STI, OS);
330 case Mips::OR:
331 case Mips::ADDu:
332 // or $r0, $r1, $zero => move $r0, $r1
333 // addu $r0, $r1, $zero => move $r0, $r1
334 return isReg<Mips::ZERO>(MI, 2) &&
335 printAlias("move", MI, Address, 0, 1, STI, OS);
336 default:
337 return false;
338 }
339 }
340
printSaveRestore(const MCInst * MI,const MCSubtargetInfo & STI,raw_ostream & O)341 void MipsInstPrinter::printSaveRestore(const MCInst *MI,
342 const MCSubtargetInfo &STI,
343 raw_ostream &O) {
344 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
345 if (i != 0) O << ", ";
346 if (MI->getOperand(i).isReg())
347 printRegName(O, MI->getOperand(i).getReg());
348 else
349 printUImm<16>(MI, i, STI, O);
350 }
351 }
352
printRegisterList(const MCInst * MI,int opNum,const MCSubtargetInfo &,raw_ostream & O)353 void MipsInstPrinter::printRegisterList(const MCInst *MI, int opNum,
354 const MCSubtargetInfo & /* STI */,
355 raw_ostream &O) {
356 // - 2 because register List is always first operand of instruction and it is
357 // always followed by memory operand (base + offset).
358 for (int i = opNum, e = MI->getNumOperands() - 2; i != e; ++i) {
359 if (i != opNum)
360 O << ", ";
361 printRegName(O, MI->getOperand(i).getReg());
362 }
363 }
364