1 //===-- MipsMCCodeEmitter.cpp - Convert Mips Code to Machine Code ---------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the MipsMCCodeEmitter class.
11 //
12 //===----------------------------------------------------------------------===//
13 //
14 
15 #include "MipsMCCodeEmitter.h"
16 #include "MCTargetDesc/MipsFixupKinds.h"
17 #include "MCTargetDesc/MipsMCExpr.h"
18 #include "MCTargetDesc/MipsMCTargetDesc.h"
19 #include "llvm/ADT/APFloat.h"
20 #include "llvm/ADT/SmallVector.h"
21 #include "llvm/MC/MCContext.h"
22 #include "llvm/MC/MCExpr.h"
23 #include "llvm/MC/MCFixup.h"
24 #include "llvm/MC/MCInst.h"
25 #include "llvm/MC/MCInstrInfo.h"
26 #include "llvm/MC/MCRegisterInfo.h"
27 #include "llvm/MC/MCSubtargetInfo.h"
28 #include "llvm/Support/raw_ostream.h"
29 
30 #define DEBUG_TYPE "mccodeemitter"
31 
32 #define GET_INSTRMAP_INFO
33 #include "MipsGenInstrInfo.inc"
34 #undef GET_INSTRMAP_INFO
35 
36 namespace llvm {
37 MCCodeEmitter *createMipsMCCodeEmitterEB(const MCInstrInfo &MCII,
38                                          const MCRegisterInfo &MRI,
39                                          MCContext &Ctx) {
40   return new MipsMCCodeEmitter(MCII, Ctx, false);
41 }
42 
43 MCCodeEmitter *createMipsMCCodeEmitterEL(const MCInstrInfo &MCII,
44                                          const MCRegisterInfo &MRI,
45                                          MCContext &Ctx) {
46   return new MipsMCCodeEmitter(MCII, Ctx, true);
47 }
48 } // End of namespace llvm.
49 
50 // If the D<shift> instruction has a shift amount that is greater
51 // than 31 (checked in calling routine), lower it to a D<shift>32 instruction
52 static void LowerLargeShift(MCInst& Inst) {
53 
54   assert(Inst.getNumOperands() == 3 && "Invalid no. of operands for shift!");
55   assert(Inst.getOperand(2).isImm());
56 
57   int64_t Shift = Inst.getOperand(2).getImm();
58   if (Shift <= 31)
59     return; // Do nothing
60   Shift -= 32;
61 
62   // saminus32
63   Inst.getOperand(2).setImm(Shift);
64 
65   switch (Inst.getOpcode()) {
66   default:
67     // Calling function is not synchronized
68     llvm_unreachable("Unexpected shift instruction");
69   case Mips::DSLL:
70     Inst.setOpcode(Mips::DSLL32);
71     return;
72   case Mips::DSRL:
73     Inst.setOpcode(Mips::DSRL32);
74     return;
75   case Mips::DSRA:
76     Inst.setOpcode(Mips::DSRA32);
77     return;
78   case Mips::DROTR:
79     Inst.setOpcode(Mips::DROTR32);
80     return;
81   }
82 }
83 
84 // Pick a DINS instruction variant based on the pos and size operands
85 static void LowerDins(MCInst& InstIn) {
86   assert(InstIn.getNumOperands() == 5 &&
87          "Invalid no. of machine operands for DINS!");
88 
89   assert(InstIn.getOperand(2).isImm());
90   int64_t pos = InstIn.getOperand(2).getImm();
91   assert(InstIn.getOperand(3).isImm());
92   int64_t size = InstIn.getOperand(3).getImm();
93 
94   if (size <= 32) {
95     if (pos < 32)  // DINS, do nothing
96       return;
97     // DINSU
98     InstIn.getOperand(2).setImm(pos - 32);
99     InstIn.setOpcode(Mips::DINSU);
100     return;
101   }
102   // DINSM
103   assert(pos < 32 && "DINS cannot have both size and pos > 32");
104   InstIn.getOperand(3).setImm(size - 32);
105   InstIn.setOpcode(Mips::DINSM);
106   return;
107 }
108 
109 bool MipsMCCodeEmitter::isMicroMips(const MCSubtargetInfo &STI) const {
110   return STI.getFeatureBits()[Mips::FeatureMicroMips];
111 }
112 
113 bool MipsMCCodeEmitter::isMips32r6(const MCSubtargetInfo &STI) const {
114   return STI.getFeatureBits()[Mips::FeatureMips32r6];
115 }
116 
117 void MipsMCCodeEmitter::EmitByte(unsigned char C, raw_ostream &OS) const {
118   OS << (char)C;
119 }
120 
121 void MipsMCCodeEmitter::EmitInstruction(uint64_t Val, unsigned Size,
122                                         const MCSubtargetInfo &STI,
123                                         raw_ostream &OS) const {
124   // Output the instruction encoding in little endian byte order.
125   // Little-endian byte ordering:
126   //   mips32r2:   4 | 3 | 2 | 1
127   //   microMIPS:  2 | 1 | 4 | 3
128   if (IsLittleEndian && Size == 4 && isMicroMips(STI)) {
129     EmitInstruction(Val >> 16, 2, STI, OS);
130     EmitInstruction(Val, 2, STI, OS);
131   } else {
132     for (unsigned i = 0; i < Size; ++i) {
133       unsigned Shift = IsLittleEndian ? i * 8 : (Size - 1 - i) * 8;
134       EmitByte((Val >> Shift) & 0xff, OS);
135     }
136   }
137 }
138 
139 /// encodeInstruction - Emit the instruction.
140 /// Size the instruction with Desc.getSize().
141 void MipsMCCodeEmitter::
142 encodeInstruction(const MCInst &MI, raw_ostream &OS,
143                   SmallVectorImpl<MCFixup> &Fixups,
144                   const MCSubtargetInfo &STI) const
145 {
146 
147   // Non-pseudo instructions that get changed for direct object
148   // only based on operand values.
149   // If this list of instructions get much longer we will move
150   // the check to a function call. Until then, this is more efficient.
151   MCInst TmpInst = MI;
152   switch (MI.getOpcode()) {
153   // If shift amount is >= 32 it the inst needs to be lowered further
154   case Mips::DSLL:
155   case Mips::DSRL:
156   case Mips::DSRA:
157   case Mips::DROTR:
158     LowerLargeShift(TmpInst);
159     break;
160     // Double extract instruction is chosen by pos and size operands
161   case Mips::DINS:
162     LowerDins(TmpInst);
163   }
164 
165   unsigned long N = Fixups.size();
166   uint32_t Binary = getBinaryCodeForInstr(TmpInst, Fixups, STI);
167 
168   // Check for unimplemented opcodes.
169   // Unfortunately in MIPS both NOP and SLL will come in with Binary == 0
170   // so we have to special check for them.
171   unsigned Opcode = TmpInst.getOpcode();
172   if ((Opcode != Mips::NOP) && (Opcode != Mips::SLL) &&
173       (Opcode != Mips::SLL_MM) && !Binary)
174     llvm_unreachable("unimplemented opcode in encodeInstruction()");
175 
176   int NewOpcode = -1;
177   if (isMicroMips(STI)) {
178     if (isMips32r6(STI)) {
179       NewOpcode = Mips::MipsR62MicroMipsR6(Opcode, Mips::Arch_micromipsr6);
180       if (NewOpcode == -1)
181         NewOpcode = Mips::Std2MicroMipsR6(Opcode, Mips::Arch_micromipsr6);
182     }
183     else
184       NewOpcode = Mips::Std2MicroMips(Opcode, Mips::Arch_micromips);
185 
186     // Check whether it is Dsp instruction.
187     if (NewOpcode == -1)
188       NewOpcode = Mips::Dsp2MicroMips(Opcode, Mips::Arch_mmdsp);
189 
190     if (NewOpcode != -1) {
191       if (Fixups.size() > N)
192         Fixups.pop_back();
193 
194       Opcode = NewOpcode;
195       TmpInst.setOpcode (NewOpcode);
196       Binary = getBinaryCodeForInstr(TmpInst, Fixups, STI);
197     }
198   }
199 
200   const MCInstrDesc &Desc = MCII.get(TmpInst.getOpcode());
201 
202   // Get byte count of instruction
203   unsigned Size = Desc.getSize();
204   if (!Size)
205     llvm_unreachable("Desc.getSize() returns 0");
206 
207   EmitInstruction(Binary, Size, STI, OS);
208 }
209 
210 /// getBranchTargetOpValue - Return binary encoding of the branch
211 /// target operand. If the machine operand requires relocation,
212 /// record the relocation and return zero.
213 unsigned MipsMCCodeEmitter::
214 getBranchTargetOpValue(const MCInst &MI, unsigned OpNo,
215                        SmallVectorImpl<MCFixup> &Fixups,
216                        const MCSubtargetInfo &STI) const {
217 
218   const MCOperand &MO = MI.getOperand(OpNo);
219 
220   // If the destination is an immediate, divide by 4.
221   if (MO.isImm()) return MO.getImm() >> 2;
222 
223   assert(MO.isExpr() &&
224          "getBranchTargetOpValue expects only expressions or immediates");
225 
226   const MCExpr *FixupExpression = MCBinaryExpr::createAdd(
227       MO.getExpr(), MCConstantExpr::create(-4, Ctx), Ctx);
228   Fixups.push_back(MCFixup::create(0, FixupExpression,
229                                    MCFixupKind(Mips::fixup_Mips_PC16)));
230   return 0;
231 }
232 
233 /// getBranchTarget7OpValueMM - Return binary encoding of the microMIPS branch
234 /// target operand. If the machine operand requires relocation,
235 /// record the relocation and return zero.
236 unsigned MipsMCCodeEmitter::
237 getBranchTarget7OpValueMM(const MCInst &MI, unsigned OpNo,
238                           SmallVectorImpl<MCFixup> &Fixups,
239                           const MCSubtargetInfo &STI) const {
240 
241   const MCOperand &MO = MI.getOperand(OpNo);
242 
243   // If the destination is an immediate, divide by 2.
244   if (MO.isImm()) return MO.getImm() >> 1;
245 
246   assert(MO.isExpr() &&
247          "getBranchTargetOpValueMM expects only expressions or immediates");
248 
249   const MCExpr *Expr = MO.getExpr();
250   Fixups.push_back(MCFixup::create(0, Expr,
251                                    MCFixupKind(Mips::fixup_MICROMIPS_PC7_S1)));
252   return 0;
253 }
254 
255 /// getBranchTargetOpValueMMPC10 - Return binary encoding of the microMIPS
256 /// 10-bit branch target operand. If the machine operand requires relocation,
257 /// record the relocation and return zero.
258 unsigned MipsMCCodeEmitter::
259 getBranchTargetOpValueMMPC10(const MCInst &MI, unsigned OpNo,
260                              SmallVectorImpl<MCFixup> &Fixups,
261                              const MCSubtargetInfo &STI) const {
262 
263   const MCOperand &MO = MI.getOperand(OpNo);
264 
265   // If the destination is an immediate, divide by 2.
266   if (MO.isImm()) return MO.getImm() >> 1;
267 
268   assert(MO.isExpr() &&
269          "getBranchTargetOpValuePC10 expects only expressions or immediates");
270 
271   const MCExpr *Expr = MO.getExpr();
272   Fixups.push_back(MCFixup::create(0, Expr,
273                    MCFixupKind(Mips::fixup_MICROMIPS_PC10_S1)));
274   return 0;
275 }
276 
277 /// getBranchTargetOpValue - Return binary encoding of the microMIPS branch
278 /// target operand. If the machine operand requires relocation,
279 /// record the relocation and return zero.
280 unsigned MipsMCCodeEmitter::
281 getBranchTargetOpValueMM(const MCInst &MI, unsigned OpNo,
282                          SmallVectorImpl<MCFixup> &Fixups,
283                          const MCSubtargetInfo &STI) const {
284 
285   const MCOperand &MO = MI.getOperand(OpNo);
286 
287   // If the destination is an immediate, divide by 2.
288   if (MO.isImm()) return MO.getImm() >> 1;
289 
290   assert(MO.isExpr() &&
291          "getBranchTargetOpValueMM expects only expressions or immediates");
292 
293   const MCExpr *Expr = MO.getExpr();
294   Fixups.push_back(MCFixup::create(0, Expr,
295                    MCFixupKind(Mips::
296                                fixup_MICROMIPS_PC16_S1)));
297   return 0;
298 }
299 
300 /// getBranchTarget21OpValue - Return binary encoding of the branch
301 /// target operand. If the machine operand requires relocation,
302 /// record the relocation and return zero.
303 unsigned MipsMCCodeEmitter::
304 getBranchTarget21OpValue(const MCInst &MI, unsigned OpNo,
305                          SmallVectorImpl<MCFixup> &Fixups,
306                          const MCSubtargetInfo &STI) const {
307 
308   const MCOperand &MO = MI.getOperand(OpNo);
309 
310   // If the destination is an immediate, divide by 4.
311   if (MO.isImm()) return MO.getImm() >> 2;
312 
313   assert(MO.isExpr() &&
314          "getBranchTarget21OpValue expects only expressions or immediates");
315 
316   const MCExpr *FixupExpression = MCBinaryExpr::createAdd(
317       MO.getExpr(), MCConstantExpr::create(-4, Ctx), Ctx);
318   Fixups.push_back(MCFixup::create(0, FixupExpression,
319                                    MCFixupKind(Mips::fixup_MIPS_PC21_S2)));
320   return 0;
321 }
322 
323 /// getBranchTarget26OpValue - Return binary encoding of the branch
324 /// target operand. If the machine operand requires relocation,
325 /// record the relocation and return zero.
326 unsigned MipsMCCodeEmitter::
327 getBranchTarget26OpValue(const MCInst &MI, unsigned OpNo,
328                          SmallVectorImpl<MCFixup> &Fixups,
329                          const MCSubtargetInfo &STI) const {
330 
331   const MCOperand &MO = MI.getOperand(OpNo);
332 
333   // If the destination is an immediate, divide by 4.
334   if (MO.isImm()) return MO.getImm() >> 2;
335 
336   assert(MO.isExpr() &&
337          "getBranchTarget26OpValue expects only expressions or immediates");
338 
339   const MCExpr *FixupExpression = MCBinaryExpr::createAdd(
340       MO.getExpr(), MCConstantExpr::create(-4, Ctx), Ctx);
341   Fixups.push_back(MCFixup::create(0, FixupExpression,
342                                    MCFixupKind(Mips::fixup_MIPS_PC26_S2)));
343   return 0;
344 }
345 
346 /// getBranchTarget26OpValueMM - Return binary encoding of the branch
347 /// target operand. If the machine operand requires relocation,
348 /// record the relocation and return zero.
349 unsigned MipsMCCodeEmitter::getBranchTarget26OpValueMM(
350     const MCInst &MI, unsigned OpNo, SmallVectorImpl<MCFixup> &Fixups,
351     const MCSubtargetInfo &STI) const {
352 
353   const MCOperand &MO = MI.getOperand(OpNo);
354 
355   // If the destination is an immediate, divide by 2.
356   if (MO.isImm())
357     return MO.getImm() >> 1;
358 
359   assert(MO.isExpr() &&
360          "getBranchTarget26OpValueMM expects only expressions or immediates");
361 
362   const MCExpr *FixupExpression = MCBinaryExpr::createAdd(
363       MO.getExpr(), MCConstantExpr::create(-4, Ctx), Ctx);
364   Fixups.push_back(MCFixup::create(0, FixupExpression,
365                                    MCFixupKind(Mips::fixup_MICROMIPS_PC26_S1)));
366   return 0;
367 }
368 
369 /// getJumpOffset16OpValue - Return binary encoding of the jump
370 /// target operand. If the machine operand requires relocation,
371 /// record the relocation and return zero.
372 unsigned MipsMCCodeEmitter::
373 getJumpOffset16OpValue(const MCInst &MI, unsigned OpNo,
374                        SmallVectorImpl<MCFixup> &Fixups,
375                        const MCSubtargetInfo &STI) const {
376 
377   const MCOperand &MO = MI.getOperand(OpNo);
378 
379   if (MO.isImm()) return MO.getImm();
380 
381   assert(MO.isExpr() &&
382          "getJumpOffset16OpValue expects only expressions or an immediate");
383 
384    // TODO: Push fixup.
385    return 0;
386 }
387 
388 /// getJumpTargetOpValue - Return binary encoding of the jump
389 /// target operand. If the machine operand requires relocation,
390 /// record the relocation and return zero.
391 unsigned MipsMCCodeEmitter::
392 getJumpTargetOpValue(const MCInst &MI, unsigned OpNo,
393                      SmallVectorImpl<MCFixup> &Fixups,
394                      const MCSubtargetInfo &STI) const {
395 
396   const MCOperand &MO = MI.getOperand(OpNo);
397   // If the destination is an immediate, divide by 4.
398   if (MO.isImm()) return MO.getImm()>>2;
399 
400   assert(MO.isExpr() &&
401          "getJumpTargetOpValue expects only expressions or an immediate");
402 
403   const MCExpr *Expr = MO.getExpr();
404   Fixups.push_back(MCFixup::create(0, Expr,
405                                    MCFixupKind(Mips::fixup_Mips_26)));
406   return 0;
407 }
408 
409 unsigned MipsMCCodeEmitter::
410 getJumpTargetOpValueMM(const MCInst &MI, unsigned OpNo,
411                        SmallVectorImpl<MCFixup> &Fixups,
412                        const MCSubtargetInfo &STI) const {
413 
414   const MCOperand &MO = MI.getOperand(OpNo);
415   // If the destination is an immediate, divide by 2.
416   if (MO.isImm()) return MO.getImm() >> 1;
417 
418   assert(MO.isExpr() &&
419          "getJumpTargetOpValueMM expects only expressions or an immediate");
420 
421   const MCExpr *Expr = MO.getExpr();
422   Fixups.push_back(MCFixup::create(0, Expr,
423                                    MCFixupKind(Mips::fixup_MICROMIPS_26_S1)));
424   return 0;
425 }
426 
427 unsigned MipsMCCodeEmitter::
428 getUImm5Lsl2Encoding(const MCInst &MI, unsigned OpNo,
429                      SmallVectorImpl<MCFixup> &Fixups,
430                      const MCSubtargetInfo &STI) const {
431 
432   const MCOperand &MO = MI.getOperand(OpNo);
433   if (MO.isImm()) {
434     // The immediate is encoded as 'immediate << 2'.
435     unsigned Res = getMachineOpValue(MI, MO, Fixups, STI);
436     assert((Res & 3) == 0);
437     return Res >> 2;
438   }
439 
440   assert(MO.isExpr() &&
441          "getUImm5Lsl2Encoding expects only expressions or an immediate");
442 
443   return 0;
444 }
445 
446 unsigned MipsMCCodeEmitter::
447 getSImm3Lsa2Value(const MCInst &MI, unsigned OpNo,
448                   SmallVectorImpl<MCFixup> &Fixups,
449                   const MCSubtargetInfo &STI) const {
450 
451   const MCOperand &MO = MI.getOperand(OpNo);
452   if (MO.isImm()) {
453     int Value = MO.getImm();
454     return Value >> 2;
455   }
456 
457   return 0;
458 }
459 
460 unsigned MipsMCCodeEmitter::
461 getUImm6Lsl2Encoding(const MCInst &MI, unsigned OpNo,
462                      SmallVectorImpl<MCFixup> &Fixups,
463                      const MCSubtargetInfo &STI) const {
464 
465   const MCOperand &MO = MI.getOperand(OpNo);
466   if (MO.isImm()) {
467     unsigned Value = MO.getImm();
468     return Value >> 2;
469   }
470 
471   return 0;
472 }
473 
474 unsigned MipsMCCodeEmitter::
475 getSImm9AddiuspValue(const MCInst &MI, unsigned OpNo,
476                      SmallVectorImpl<MCFixup> &Fixups,
477                      const MCSubtargetInfo &STI) const {
478 
479   const MCOperand &MO = MI.getOperand(OpNo);
480   if (MO.isImm()) {
481     unsigned Binary = (MO.getImm() >> 2) & 0x0000ffff;
482     return (((Binary & 0x8000) >> 7) | (Binary & 0x00ff));
483   }
484 
485   return 0;
486 }
487 
488 unsigned MipsMCCodeEmitter::
489 getExprOpValue(const MCExpr *Expr, SmallVectorImpl<MCFixup> &Fixups,
490                const MCSubtargetInfo &STI) const {
491   int64_t Res;
492 
493   if (Expr->evaluateAsAbsolute(Res))
494     return Res;
495 
496   MCExpr::ExprKind Kind = Expr->getKind();
497   if (Kind == MCExpr::Constant) {
498     return cast<MCConstantExpr>(Expr)->getValue();
499   }
500 
501   if (Kind == MCExpr::Binary) {
502     unsigned Res = getExprOpValue(cast<MCBinaryExpr>(Expr)->getLHS(), Fixups, STI);
503     Res += getExprOpValue(cast<MCBinaryExpr>(Expr)->getRHS(), Fixups, STI);
504     return Res;
505   }
506 
507   if (Kind == MCExpr::Target) {
508     const MipsMCExpr *MipsExpr = cast<MipsMCExpr>(Expr);
509 
510     Mips::Fixups FixupKind = Mips::Fixups(0);
511     switch (MipsExpr->getKind()) {
512     default: llvm_unreachable("Unsupported fixup kind for target expression!");
513     case MipsMCExpr::VK_Mips_HIGHEST:
514       FixupKind = Mips::fixup_Mips_HIGHEST;
515       break;
516     case MipsMCExpr::VK_Mips_HIGHER:
517       FixupKind = Mips::fixup_Mips_HIGHER;
518       break;
519     case MipsMCExpr::VK_Mips_HI:
520       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_HI16
521                                    : Mips::fixup_Mips_HI16;
522       break;
523     case MipsMCExpr::VK_Mips_LO:
524       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_LO16
525                                    : Mips::fixup_Mips_LO16;
526       break;
527     }
528     Fixups.push_back(MCFixup::create(0, MipsExpr, MCFixupKind(FixupKind)));
529     return 0;
530   }
531 
532   if (Kind == MCExpr::SymbolRef) {
533     Mips::Fixups FixupKind = Mips::Fixups(0);
534 
535     switch(cast<MCSymbolRefExpr>(Expr)->getKind()) {
536     default: llvm_unreachable("Unknown fixup kind!");
537       break;
538     case MCSymbolRefExpr::VK_None:
539       FixupKind = Mips::fixup_Mips_32; // FIXME: This is ok for O32/N32 but not N64.
540       break;
541     case MCSymbolRefExpr::VK_Mips_GPOFF_HI :
542       FixupKind = Mips::fixup_Mips_GPOFF_HI;
543       break;
544     case MCSymbolRefExpr::VK_Mips_GPOFF_LO :
545       FixupKind = Mips::fixup_Mips_GPOFF_LO;
546       break;
547     case MCSymbolRefExpr::VK_Mips_GOT_PAGE :
548       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_GOT_PAGE
549                               : Mips::fixup_Mips_GOT_PAGE;
550       break;
551     case MCSymbolRefExpr::VK_Mips_GOT_OFST :
552       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_GOT_OFST
553                               : Mips::fixup_Mips_GOT_OFST;
554       break;
555     case MCSymbolRefExpr::VK_Mips_GOT_DISP :
556       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_GOT_DISP
557                               : Mips::fixup_Mips_GOT_DISP;
558       break;
559     case MCSymbolRefExpr::VK_Mips_GPREL:
560       FixupKind = Mips::fixup_Mips_GPREL16;
561       break;
562     case MCSymbolRefExpr::VK_Mips_GOT_CALL:
563       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_CALL16
564                               : Mips::fixup_Mips_CALL16;
565       break;
566     case MCSymbolRefExpr::VK_Mips_GOT16:
567       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_GOT16
568                               : Mips::fixup_Mips_GOT_Global;
569       break;
570     case MCSymbolRefExpr::VK_Mips_GOT:
571       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_GOT16
572                               : Mips::fixup_Mips_GOT_Local;
573       break;
574     case MCSymbolRefExpr::VK_Mips_ABS_HI:
575       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_HI16
576                               : Mips::fixup_Mips_HI16;
577       break;
578     case MCSymbolRefExpr::VK_Mips_ABS_LO:
579       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_LO16
580                               : Mips::fixup_Mips_LO16;
581       break;
582     case MCSymbolRefExpr::VK_Mips_TLSGD:
583       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_GD
584                               : Mips::fixup_Mips_TLSGD;
585       break;
586     case MCSymbolRefExpr::VK_Mips_TLSLDM:
587       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_LDM
588                               : Mips::fixup_Mips_TLSLDM;
589       break;
590     case MCSymbolRefExpr::VK_Mips_DTPREL_HI:
591       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_DTPREL_HI16
592                               : Mips::fixup_Mips_DTPREL_HI;
593       break;
594     case MCSymbolRefExpr::VK_Mips_DTPREL_LO:
595       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_DTPREL_LO16
596                               : Mips::fixup_Mips_DTPREL_LO;
597       break;
598     case MCSymbolRefExpr::VK_Mips_GOTTPREL:
599       FixupKind = Mips::fixup_Mips_GOTTPREL;
600       break;
601     case MCSymbolRefExpr::VK_Mips_TPREL_HI:
602       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_TPREL_HI16
603                               : Mips::fixup_Mips_TPREL_HI;
604       break;
605     case MCSymbolRefExpr::VK_Mips_TPREL_LO:
606       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_TPREL_LO16
607                               : Mips::fixup_Mips_TPREL_LO;
608       break;
609     case MCSymbolRefExpr::VK_Mips_HIGHER:
610       FixupKind = Mips::fixup_Mips_HIGHER;
611       break;
612     case MCSymbolRefExpr::VK_Mips_HIGHEST:
613       FixupKind = Mips::fixup_Mips_HIGHEST;
614       break;
615     case MCSymbolRefExpr::VK_Mips_GOT_HI16:
616       FixupKind = Mips::fixup_Mips_GOT_HI16;
617       break;
618     case MCSymbolRefExpr::VK_Mips_GOT_LO16:
619       FixupKind = Mips::fixup_Mips_GOT_LO16;
620       break;
621     case MCSymbolRefExpr::VK_Mips_CALL_HI16:
622       FixupKind = Mips::fixup_Mips_CALL_HI16;
623       break;
624     case MCSymbolRefExpr::VK_Mips_CALL_LO16:
625       FixupKind = Mips::fixup_Mips_CALL_LO16;
626       break;
627     case MCSymbolRefExpr::VK_Mips_PCREL_HI16:
628       FixupKind = Mips::fixup_MIPS_PCHI16;
629       break;
630     case MCSymbolRefExpr::VK_Mips_PCREL_LO16:
631       FixupKind = Mips::fixup_MIPS_PCLO16;
632       break;
633     } // switch
634 
635     Fixups.push_back(MCFixup::create(0, Expr, MCFixupKind(FixupKind)));
636     return 0;
637   }
638   return 0;
639 }
640 
641 /// getMachineOpValue - Return binary encoding of operand. If the machine
642 /// operand requires relocation, record the relocation and return zero.
643 unsigned MipsMCCodeEmitter::
644 getMachineOpValue(const MCInst &MI, const MCOperand &MO,
645                   SmallVectorImpl<MCFixup> &Fixups,
646                   const MCSubtargetInfo &STI) const {
647   if (MO.isReg()) {
648     unsigned Reg = MO.getReg();
649     unsigned RegNo = Ctx.getRegisterInfo()->getEncodingValue(Reg);
650     return RegNo;
651   } else if (MO.isImm()) {
652     return static_cast<unsigned>(MO.getImm());
653   } else if (MO.isFPImm()) {
654     return static_cast<unsigned>(APFloat(MO.getFPImm())
655         .bitcastToAPInt().getHiBits(32).getLimitedValue());
656   }
657   // MO must be an Expr.
658   assert(MO.isExpr());
659   return getExprOpValue(MO.getExpr(),Fixups, STI);
660 }
661 
662 /// Return binary encoding of memory related operand.
663 /// If the offset operand requires relocation, record the relocation.
664 template <unsigned ShiftAmount>
665 unsigned MipsMCCodeEmitter::getMemEncoding(const MCInst &MI, unsigned OpNo,
666                                            SmallVectorImpl<MCFixup> &Fixups,
667                                            const MCSubtargetInfo &STI) const {
668   // Base register is encoded in bits 20-16, offset is encoded in bits 15-0.
669   assert(MI.getOperand(OpNo).isReg());
670   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo),Fixups, STI) << 16;
671   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI);
672 
673   // Apply the scale factor if there is one.
674   OffBits >>= ShiftAmount;
675 
676   return (OffBits & 0xFFFF) | RegBits;
677 }
678 
679 unsigned MipsMCCodeEmitter::
680 getMemEncodingMMImm4(const MCInst &MI, unsigned OpNo,
681                      SmallVectorImpl<MCFixup> &Fixups,
682                      const MCSubtargetInfo &STI) const {
683   // Base register is encoded in bits 6-4, offset is encoded in bits 3-0.
684   assert(MI.getOperand(OpNo).isReg());
685   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo),
686                                        Fixups, STI) << 4;
687   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1),
688                                        Fixups, STI);
689 
690   return (OffBits & 0xF) | RegBits;
691 }
692 
693 unsigned MipsMCCodeEmitter::
694 getMemEncodingMMImm4Lsl1(const MCInst &MI, unsigned OpNo,
695                          SmallVectorImpl<MCFixup> &Fixups,
696                          const MCSubtargetInfo &STI) const {
697   // Base register is encoded in bits 6-4, offset is encoded in bits 3-0.
698   assert(MI.getOperand(OpNo).isReg());
699   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo),
700                                        Fixups, STI) << 4;
701   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1),
702                                        Fixups, STI) >> 1;
703 
704   return (OffBits & 0xF) | RegBits;
705 }
706 
707 unsigned MipsMCCodeEmitter::
708 getMemEncodingMMImm4Lsl2(const MCInst &MI, unsigned OpNo,
709                          SmallVectorImpl<MCFixup> &Fixups,
710                          const MCSubtargetInfo &STI) const {
711   // Base register is encoded in bits 6-4, offset is encoded in bits 3-0.
712   assert(MI.getOperand(OpNo).isReg());
713   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo),
714                                        Fixups, STI) << 4;
715   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1),
716                                        Fixups, STI) >> 2;
717 
718   return (OffBits & 0xF) | RegBits;
719 }
720 
721 unsigned MipsMCCodeEmitter::
722 getMemEncodingMMSPImm5Lsl2(const MCInst &MI, unsigned OpNo,
723                            SmallVectorImpl<MCFixup> &Fixups,
724                            const MCSubtargetInfo &STI) const {
725   // Register is encoded in bits 9-5, offset is encoded in bits 4-0.
726   assert(MI.getOperand(OpNo).isReg() &&
727          (MI.getOperand(OpNo).getReg() == Mips::SP ||
728          MI.getOperand(OpNo).getReg() == Mips::SP_64) &&
729          "Unexpected base register!");
730   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1),
731                                        Fixups, STI) >> 2;
732 
733   return OffBits & 0x1F;
734 }
735 
736 unsigned MipsMCCodeEmitter::
737 getMemEncodingMMGPImm7Lsl2(const MCInst &MI, unsigned OpNo,
738                            SmallVectorImpl<MCFixup> &Fixups,
739                            const MCSubtargetInfo &STI) const {
740   // Register is encoded in bits 9-7, offset is encoded in bits 6-0.
741   assert(MI.getOperand(OpNo).isReg() &&
742          MI.getOperand(OpNo).getReg() == Mips::GP &&
743          "Unexpected base register!");
744 
745   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1),
746                                        Fixups, STI) >> 2;
747 
748   return OffBits & 0x7F;
749 }
750 
751 unsigned MipsMCCodeEmitter::
752 getMemEncodingMMImm9(const MCInst &MI, unsigned OpNo,
753                      SmallVectorImpl<MCFixup> &Fixups,
754                      const MCSubtargetInfo &STI) const {
755   // Base register is encoded in bits 20-16, offset is encoded in bits 8-0.
756   assert(MI.getOperand(OpNo).isReg());
757   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups,
758                                        STI) << 16;
759   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo + 1), Fixups, STI);
760 
761   return (OffBits & 0x1FF) | RegBits;
762 }
763 
764 unsigned MipsMCCodeEmitter::
765 getMemEncodingMMImm12(const MCInst &MI, unsigned OpNo,
766                       SmallVectorImpl<MCFixup> &Fixups,
767                       const MCSubtargetInfo &STI) const {
768   // opNum can be invalid if instruction had reglist as operand.
769   // MemOperand is always last operand of instruction (base + offset).
770   switch (MI.getOpcode()) {
771   default:
772     break;
773   case Mips::SWM32_MM:
774   case Mips::LWM32_MM:
775     OpNo = MI.getNumOperands() - 2;
776     break;
777   }
778 
779   // Base register is encoded in bits 20-16, offset is encoded in bits 11-0.
780   assert(MI.getOperand(OpNo).isReg());
781   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI) << 16;
782   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI);
783 
784   return (OffBits & 0x0FFF) | RegBits;
785 }
786 
787 unsigned MipsMCCodeEmitter::
788 getMemEncodingMMImm16(const MCInst &MI, unsigned OpNo,
789                       SmallVectorImpl<MCFixup> &Fixups,
790                       const MCSubtargetInfo &STI) const {
791   // Base register is encoded in bits 20-16, offset is encoded in bits 15-0.
792   assert(MI.getOperand(OpNo).isReg());
793   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups,
794                                        STI) << 16;
795   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI);
796 
797   return (OffBits & 0xFFFF) | RegBits;
798 }
799 
800 unsigned MipsMCCodeEmitter::
801 getMemEncodingMMImm4sp(const MCInst &MI, unsigned OpNo,
802                        SmallVectorImpl<MCFixup> &Fixups,
803                        const MCSubtargetInfo &STI) const {
804   // opNum can be invalid if instruction had reglist as operand
805   // MemOperand is always last operand of instruction (base + offset)
806   switch (MI.getOpcode()) {
807   default:
808     break;
809   case Mips::SWM16_MM:
810   case Mips::SWM16_MMR6:
811   case Mips::LWM16_MM:
812   case Mips::LWM16_MMR6:
813     OpNo = MI.getNumOperands() - 2;
814     break;
815   }
816 
817   // Offset is encoded in bits 4-0.
818   assert(MI.getOperand(OpNo).isReg());
819   // Base register is always SP - thus it is not encoded.
820   assert(MI.getOperand(OpNo+1).isImm());
821   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI);
822 
823   return ((OffBits >> 2) & 0x0F);
824 }
825 
826 // FIXME: should be called getMSBEncoding
827 //
828 unsigned
829 MipsMCCodeEmitter::getSizeInsEncoding(const MCInst &MI, unsigned OpNo,
830                                       SmallVectorImpl<MCFixup> &Fixups,
831                                       const MCSubtargetInfo &STI) const {
832   assert(MI.getOperand(OpNo-1).isImm());
833   assert(MI.getOperand(OpNo).isImm());
834   unsigned Position = getMachineOpValue(MI, MI.getOperand(OpNo-1), Fixups, STI);
835   unsigned Size = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI);
836 
837   return Position + Size - 1;
838 }
839 
840 template <unsigned Bits, int Offset>
841 unsigned
842 MipsMCCodeEmitter::getUImmWithOffsetEncoding(const MCInst &MI, unsigned OpNo,
843                                              SmallVectorImpl<MCFixup> &Fixups,
844                                              const MCSubtargetInfo &STI) const {
845   assert(MI.getOperand(OpNo).isImm());
846   unsigned Value = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI);
847   Value -= Offset;
848   return Value;
849 }
850 
851 unsigned
852 MipsMCCodeEmitter::getSimm19Lsl2Encoding(const MCInst &MI, unsigned OpNo,
853                                          SmallVectorImpl<MCFixup> &Fixups,
854                                          const MCSubtargetInfo &STI) const {
855   const MCOperand &MO = MI.getOperand(OpNo);
856   if (MO.isImm()) {
857     // The immediate is encoded as 'immediate << 2'.
858     unsigned Res = getMachineOpValue(MI, MO, Fixups, STI);
859     assert((Res & 3) == 0);
860     return Res >> 2;
861   }
862 
863   assert(MO.isExpr() &&
864          "getSimm19Lsl2Encoding expects only expressions or an immediate");
865 
866   const MCExpr *Expr = MO.getExpr();
867   Mips::Fixups FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_PC19_S2
868                                             : Mips::fixup_MIPS_PC19_S2;
869   Fixups.push_back(MCFixup::create(0, Expr, MCFixupKind(FixupKind)));
870   return 0;
871 }
872 
873 unsigned
874 MipsMCCodeEmitter::getSimm18Lsl3Encoding(const MCInst &MI, unsigned OpNo,
875                                          SmallVectorImpl<MCFixup> &Fixups,
876                                          const MCSubtargetInfo &STI) const {
877   const MCOperand &MO = MI.getOperand(OpNo);
878   if (MO.isImm()) {
879     // The immediate is encoded as 'immediate << 3'.
880     unsigned Res = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI);
881     assert((Res & 7) == 0);
882     return Res >> 3;
883   }
884 
885   assert(MO.isExpr() &&
886          "getSimm18Lsl2Encoding expects only expressions or an immediate");
887 
888   const MCExpr *Expr = MO.getExpr();
889   Mips::Fixups FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_PC18_S3
890                                             : Mips::fixup_MIPS_PC18_S3;
891   Fixups.push_back(MCFixup::create(0, Expr, MCFixupKind(FixupKind)));
892   return 0;
893 }
894 
895 unsigned
896 MipsMCCodeEmitter::getUImm3Mod8Encoding(const MCInst &MI, unsigned OpNo,
897                                         SmallVectorImpl<MCFixup> &Fixups,
898                                         const MCSubtargetInfo &STI) const {
899   assert(MI.getOperand(OpNo).isImm());
900   const MCOperand &MO = MI.getOperand(OpNo);
901   return MO.getImm() % 8;
902 }
903 
904 unsigned
905 MipsMCCodeEmitter::getUImm4AndValue(const MCInst &MI, unsigned OpNo,
906                                     SmallVectorImpl<MCFixup> &Fixups,
907                                     const MCSubtargetInfo &STI) const {
908   assert(MI.getOperand(OpNo).isImm());
909   const MCOperand &MO = MI.getOperand(OpNo);
910   unsigned Value = MO.getImm();
911   switch (Value) {
912     case 128:   return 0x0;
913     case 1:     return 0x1;
914     case 2:     return 0x2;
915     case 3:     return 0x3;
916     case 4:     return 0x4;
917     case 7:     return 0x5;
918     case 8:     return 0x6;
919     case 15:    return 0x7;
920     case 16:    return 0x8;
921     case 31:    return 0x9;
922     case 32:    return 0xa;
923     case 63:    return 0xb;
924     case 64:    return 0xc;
925     case 255:   return 0xd;
926     case 32768: return 0xe;
927     case 65535: return 0xf;
928   }
929   llvm_unreachable("Unexpected value");
930 }
931 
932 unsigned
933 MipsMCCodeEmitter::getRegisterListOpValue(const MCInst &MI, unsigned OpNo,
934                                           SmallVectorImpl<MCFixup> &Fixups,
935                                           const MCSubtargetInfo &STI) const {
936   unsigned res = 0;
937 
938   // Register list operand is always first operand of instruction and it is
939   // placed before memory operand (register + imm).
940 
941   for (unsigned I = OpNo, E = MI.getNumOperands() - 2; I < E; ++I) {
942     unsigned Reg = MI.getOperand(I).getReg();
943     unsigned RegNo = Ctx.getRegisterInfo()->getEncodingValue(Reg);
944     if (RegNo != 31)
945       res++;
946     else
947       res |= 0x10;
948   }
949   return res;
950 }
951 
952 unsigned
953 MipsMCCodeEmitter::getRegisterListOpValue16(const MCInst &MI, unsigned OpNo,
954                                             SmallVectorImpl<MCFixup> &Fixups,
955                                             const MCSubtargetInfo &STI) const {
956   return (MI.getNumOperands() - 4);
957 }
958 
959 unsigned
960 MipsMCCodeEmitter::getRegisterPairOpValue(const MCInst &MI, unsigned OpNo,
961                                           SmallVectorImpl<MCFixup> &Fixups,
962                                           const MCSubtargetInfo &STI) const {
963   return getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI);
964 }
965 
966 unsigned
967 MipsMCCodeEmitter::getMovePRegPairOpValue(const MCInst &MI, unsigned OpNo,
968                                           SmallVectorImpl<MCFixup> &Fixups,
969                                           const MCSubtargetInfo &STI) const {
970   unsigned res = 0;
971 
972   if (MI.getOperand(0).getReg() == Mips::A1 &&
973       MI.getOperand(1).getReg() == Mips::A2)
974     res = 0;
975   else if (MI.getOperand(0).getReg() == Mips::A1 &&
976            MI.getOperand(1).getReg() == Mips::A3)
977     res = 1;
978   else if (MI.getOperand(0).getReg() == Mips::A2 &&
979            MI.getOperand(1).getReg() == Mips::A3)
980     res = 2;
981   else if (MI.getOperand(0).getReg() == Mips::A0 &&
982            MI.getOperand(1).getReg() == Mips::S5)
983     res = 3;
984   else if (MI.getOperand(0).getReg() == Mips::A0 &&
985            MI.getOperand(1).getReg() == Mips::S6)
986     res = 4;
987   else if (MI.getOperand(0).getReg() == Mips::A0 &&
988            MI.getOperand(1).getReg() == Mips::A1)
989     res = 5;
990   else if (MI.getOperand(0).getReg() == Mips::A0 &&
991            MI.getOperand(1).getReg() == Mips::A2)
992     res = 6;
993   else if (MI.getOperand(0).getReg() == Mips::A0 &&
994            MI.getOperand(1).getReg() == Mips::A3)
995     res = 7;
996 
997   return res;
998 }
999 
1000 unsigned
1001 MipsMCCodeEmitter::getSimm23Lsl2Encoding(const MCInst &MI, unsigned OpNo,
1002                                          SmallVectorImpl<MCFixup> &Fixups,
1003                                          const MCSubtargetInfo &STI) const {
1004   const MCOperand &MO = MI.getOperand(OpNo);
1005   assert(MO.isImm() && "getSimm23Lsl2Encoding expects only an immediate");
1006   // The immediate is encoded as 'immediate >> 2'.
1007   unsigned Res = static_cast<unsigned>(MO.getImm());
1008   assert((Res & 3) == 0);
1009   return Res >> 2;
1010 }
1011 
1012 #include "MipsGenMCCodeEmitter.inc"
1013