xref: /minix3/external/bsd/llvm/dist/llvm/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp (revision 0a6a1f1d05b60e214de2f05a7310ddd1f0e590e7)
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/MCSubtargetInfo.h"
27 #include "llvm/Support/raw_ostream.h"
28 
29 #define DEBUG_TYPE "mccodeemitter"
30 
31 #define GET_INSTRMAP_INFO
32 #include "MipsGenInstrInfo.inc"
33 #undef GET_INSTRMAP_INFO
34 
35 namespace llvm {
createMipsMCCodeEmitterEB(const MCInstrInfo & MCII,const MCRegisterInfo & MRI,const MCSubtargetInfo & STI,MCContext & Ctx)36 MCCodeEmitter *createMipsMCCodeEmitterEB(const MCInstrInfo &MCII,
37                                          const MCRegisterInfo &MRI,
38                                          const MCSubtargetInfo &STI,
39                                          MCContext &Ctx) {
40   return new MipsMCCodeEmitter(MCII, Ctx, false);
41 }
42 
createMipsMCCodeEmitterEL(const MCInstrInfo & MCII,const MCRegisterInfo & MRI,const MCSubtargetInfo & STI,MCContext & Ctx)43 MCCodeEmitter *createMipsMCCodeEmitterEL(const MCInstrInfo &MCII,
44                                          const MCRegisterInfo &MRI,
45                                          const MCSubtargetInfo &STI,
46                                          MCContext &Ctx) {
47   return new MipsMCCodeEmitter(MCII, Ctx, true);
48 }
49 } // End of namespace llvm.
50 
51 // If the D<shift> instruction has a shift amount that is greater
52 // than 31 (checked in calling routine), lower it to a D<shift>32 instruction
LowerLargeShift(MCInst & Inst)53 static void LowerLargeShift(MCInst& Inst) {
54 
55   assert(Inst.getNumOperands() == 3 && "Invalid no. of operands for shift!");
56   assert(Inst.getOperand(2).isImm());
57 
58   int64_t Shift = Inst.getOperand(2).getImm();
59   if (Shift <= 31)
60     return; // Do nothing
61   Shift -= 32;
62 
63   // saminus32
64   Inst.getOperand(2).setImm(Shift);
65 
66   switch (Inst.getOpcode()) {
67   default:
68     // Calling function is not synchronized
69     llvm_unreachable("Unexpected shift instruction");
70   case Mips::DSLL:
71     Inst.setOpcode(Mips::DSLL32);
72     return;
73   case Mips::DSRL:
74     Inst.setOpcode(Mips::DSRL32);
75     return;
76   case Mips::DSRA:
77     Inst.setOpcode(Mips::DSRA32);
78     return;
79   case Mips::DROTR:
80     Inst.setOpcode(Mips::DROTR32);
81     return;
82   }
83 }
84 
85 // Pick a DEXT or DINS instruction variant based on the pos and size operands
LowerDextDins(MCInst & InstIn)86 static void LowerDextDins(MCInst& InstIn) {
87   int Opcode = InstIn.getOpcode();
88 
89   if (Opcode == Mips::DEXT)
90     assert(InstIn.getNumOperands() == 4 &&
91            "Invalid no. of machine operands for DEXT!");
92   else // Only DEXT and DINS are possible
93     assert(InstIn.getNumOperands() == 5 &&
94            "Invalid no. of machine operands for DINS!");
95 
96   assert(InstIn.getOperand(2).isImm());
97   int64_t pos = InstIn.getOperand(2).getImm();
98   assert(InstIn.getOperand(3).isImm());
99   int64_t size = InstIn.getOperand(3).getImm();
100 
101   if (size <= 32) {
102     if (pos < 32)  // DEXT/DINS, do nothing
103       return;
104     // DEXTU/DINSU
105     InstIn.getOperand(2).setImm(pos - 32);
106     InstIn.setOpcode((Opcode == Mips::DEXT) ? Mips::DEXTU : Mips::DINSU);
107     return;
108   }
109   // DEXTM/DINSM
110   assert(pos < 32 && "DEXT/DINS cannot have both size and pos > 32");
111   InstIn.getOperand(3).setImm(size - 32);
112   InstIn.setOpcode((Opcode == Mips::DEXT) ? Mips::DEXTM : Mips::DINSM);
113   return;
114 }
115 
isMicroMips(const MCSubtargetInfo & STI) const116 bool MipsMCCodeEmitter::isMicroMips(const MCSubtargetInfo &STI) const {
117   return STI.getFeatureBits() & Mips::FeatureMicroMips;
118 }
119 
EmitByte(unsigned char C,raw_ostream & OS) const120 void MipsMCCodeEmitter::EmitByte(unsigned char C, raw_ostream &OS) const {
121   OS << (char)C;
122 }
123 
EmitInstruction(uint64_t Val,unsigned Size,const MCSubtargetInfo & STI,raw_ostream & OS) const124 void MipsMCCodeEmitter::EmitInstruction(uint64_t Val, unsigned Size,
125                                         const MCSubtargetInfo &STI,
126                                         raw_ostream &OS) const {
127   // Output the instruction encoding in little endian byte order.
128   // Little-endian byte ordering:
129   //   mips32r2:   4 | 3 | 2 | 1
130   //   microMIPS:  2 | 1 | 4 | 3
131   if (IsLittleEndian && Size == 4 && isMicroMips(STI)) {
132     EmitInstruction(Val >> 16, 2, STI, OS);
133     EmitInstruction(Val, 2, STI, OS);
134   } else {
135     for (unsigned i = 0; i < Size; ++i) {
136       unsigned Shift = IsLittleEndian ? i * 8 : (Size - 1 - i) * 8;
137       EmitByte((Val >> Shift) & 0xff, OS);
138     }
139   }
140 }
141 
142 /// EncodeInstruction - Emit the instruction.
143 /// Size the instruction with Desc.getSize().
144 void MipsMCCodeEmitter::
EncodeInstruction(const MCInst & MI,raw_ostream & OS,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const145 EncodeInstruction(const MCInst &MI, raw_ostream &OS,
146                   SmallVectorImpl<MCFixup> &Fixups,
147                   const MCSubtargetInfo &STI) const
148 {
149 
150   // Non-pseudo instructions that get changed for direct object
151   // only based on operand values.
152   // If this list of instructions get much longer we will move
153   // the check to a function call. Until then, this is more efficient.
154   MCInst TmpInst = MI;
155   switch (MI.getOpcode()) {
156   // If shift amount is >= 32 it the inst needs to be lowered further
157   case Mips::DSLL:
158   case Mips::DSRL:
159   case Mips::DSRA:
160   case Mips::DROTR:
161     LowerLargeShift(TmpInst);
162     break;
163     // Double extract instruction is chosen by pos and size operands
164   case Mips::DEXT:
165   case Mips::DINS:
166     LowerDextDins(TmpInst);
167   }
168 
169   unsigned long N = Fixups.size();
170   uint32_t Binary = getBinaryCodeForInstr(TmpInst, Fixups, STI);
171 
172   // Check for unimplemented opcodes.
173   // Unfortunately in MIPS both NOP and SLL will come in with Binary == 0
174   // so we have to special check for them.
175   unsigned Opcode = TmpInst.getOpcode();
176   if ((Opcode != Mips::NOP) && (Opcode != Mips::SLL) &&
177       (Opcode != Mips::SLL_MM) && !Binary)
178     llvm_unreachable("unimplemented opcode in EncodeInstruction()");
179 
180   if (STI.getFeatureBits() & Mips::FeatureMicroMips) {
181     int NewOpcode = Mips::Std2MicroMips (Opcode, Mips::Arch_micromips);
182     if (NewOpcode != -1) {
183       if (Fixups.size() > N)
184         Fixups.pop_back();
185       Opcode = NewOpcode;
186       TmpInst.setOpcode (NewOpcode);
187       Binary = getBinaryCodeForInstr(TmpInst, Fixups, STI);
188     }
189   }
190 
191   const MCInstrDesc &Desc = MCII.get(TmpInst.getOpcode());
192 
193   // Get byte count of instruction
194   unsigned Size = Desc.getSize();
195   if (!Size)
196     llvm_unreachable("Desc.getSize() returns 0");
197 
198   EmitInstruction(Binary, Size, STI, OS);
199 }
200 
201 /// getBranchTargetOpValue - Return binary encoding of the branch
202 /// target operand. If the machine operand requires relocation,
203 /// record the relocation and return zero.
204 unsigned MipsMCCodeEmitter::
getBranchTargetOpValue(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const205 getBranchTargetOpValue(const MCInst &MI, unsigned OpNo,
206                        SmallVectorImpl<MCFixup> &Fixups,
207                        const MCSubtargetInfo &STI) const {
208 
209   const MCOperand &MO = MI.getOperand(OpNo);
210 
211   // If the destination is an immediate, divide by 4.
212   if (MO.isImm()) return MO.getImm() >> 2;
213 
214   assert(MO.isExpr() &&
215          "getBranchTargetOpValue expects only expressions or immediates");
216 
217   const MCExpr *Expr = MO.getExpr();
218   Fixups.push_back(MCFixup::Create(0, Expr,
219                                    MCFixupKind(Mips::fixup_Mips_PC16)));
220   return 0;
221 }
222 
223 /// getBranchTarget7OpValueMM - Return binary encoding of the microMIPS branch
224 /// target operand. If the machine operand requires relocation,
225 /// record the relocation and return zero.
226 unsigned MipsMCCodeEmitter::
getBranchTarget7OpValueMM(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const227 getBranchTarget7OpValueMM(const MCInst &MI, unsigned OpNo,
228                           SmallVectorImpl<MCFixup> &Fixups,
229                           const MCSubtargetInfo &STI) const {
230 
231   const MCOperand &MO = MI.getOperand(OpNo);
232 
233   // If the destination is an immediate, divide by 2.
234   if (MO.isImm()) return MO.getImm() >> 1;
235 
236   assert(MO.isExpr() &&
237          "getBranchTargetOpValueMM expects only expressions or immediates");
238 
239   const MCExpr *Expr = MO.getExpr();
240   Fixups.push_back(MCFixup::Create(0, Expr,
241                                    MCFixupKind(Mips::fixup_MICROMIPS_PC7_S1)));
242   return 0;
243 }
244 
245 /// getBranchTargetOpValue - Return binary encoding of the microMIPS branch
246 /// target operand. If the machine operand requires relocation,
247 /// record the relocation and return zero.
248 unsigned MipsMCCodeEmitter::
getBranchTargetOpValueMM(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const249 getBranchTargetOpValueMM(const MCInst &MI, unsigned OpNo,
250                          SmallVectorImpl<MCFixup> &Fixups,
251                          const MCSubtargetInfo &STI) const {
252 
253   const MCOperand &MO = MI.getOperand(OpNo);
254 
255   // If the destination is an immediate, divide by 2.
256   if (MO.isImm()) return MO.getImm() >> 1;
257 
258   assert(MO.isExpr() &&
259          "getBranchTargetOpValueMM expects only expressions or immediates");
260 
261   const MCExpr *Expr = MO.getExpr();
262   Fixups.push_back(MCFixup::Create(0, Expr,
263                    MCFixupKind(Mips::
264                                fixup_MICROMIPS_PC16_S1)));
265   return 0;
266 }
267 
268 /// getBranchTarget21OpValue - Return binary encoding of the branch
269 /// target operand. If the machine operand requires relocation,
270 /// record the relocation and return zero.
271 unsigned MipsMCCodeEmitter::
getBranchTarget21OpValue(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const272 getBranchTarget21OpValue(const MCInst &MI, unsigned OpNo,
273                          SmallVectorImpl<MCFixup> &Fixups,
274                          const MCSubtargetInfo &STI) const {
275 
276   const MCOperand &MO = MI.getOperand(OpNo);
277 
278   // If the destination is an immediate, divide by 4.
279   if (MO.isImm()) return MO.getImm() >> 2;
280 
281   assert(MO.isExpr() &&
282          "getBranchTarget21OpValue expects only expressions or immediates");
283 
284   const MCExpr *Expr = MO.getExpr();
285   Fixups.push_back(MCFixup::Create(0, Expr,
286                                    MCFixupKind(Mips::fixup_MIPS_PC21_S2)));
287   return 0;
288 }
289 
290 /// getBranchTarget26OpValue - Return binary encoding of the branch
291 /// target operand. If the machine operand requires relocation,
292 /// record the relocation and return zero.
293 unsigned MipsMCCodeEmitter::
getBranchTarget26OpValue(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const294 getBranchTarget26OpValue(const MCInst &MI, unsigned OpNo,
295                          SmallVectorImpl<MCFixup> &Fixups,
296                          const MCSubtargetInfo &STI) const {
297 
298   const MCOperand &MO = MI.getOperand(OpNo);
299 
300   // If the destination is an immediate, divide by 4.
301   if (MO.isImm()) return MO.getImm() >> 2;
302 
303   assert(MO.isExpr() &&
304          "getBranchTarget26OpValue expects only expressions or immediates");
305 
306   const MCExpr *Expr = MO.getExpr();
307   Fixups.push_back(MCFixup::Create(0, Expr,
308                                    MCFixupKind(Mips::fixup_MIPS_PC26_S2)));
309   return 0;
310 }
311 
312 /// getJumpOffset16OpValue - Return binary encoding of the jump
313 /// target operand. If the machine operand requires relocation,
314 /// record the relocation and return zero.
315 unsigned MipsMCCodeEmitter::
getJumpOffset16OpValue(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const316 getJumpOffset16OpValue(const MCInst &MI, unsigned OpNo,
317                        SmallVectorImpl<MCFixup> &Fixups,
318                        const MCSubtargetInfo &STI) const {
319 
320   const MCOperand &MO = MI.getOperand(OpNo);
321 
322   if (MO.isImm()) return MO.getImm();
323 
324   assert(MO.isExpr() &&
325          "getJumpOffset16OpValue expects only expressions or an immediate");
326 
327    // TODO: Push fixup.
328    return 0;
329 }
330 
331 /// getJumpTargetOpValue - Return binary encoding of the jump
332 /// target operand. If the machine operand requires relocation,
333 /// record the relocation and return zero.
334 unsigned MipsMCCodeEmitter::
getJumpTargetOpValue(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const335 getJumpTargetOpValue(const MCInst &MI, unsigned OpNo,
336                      SmallVectorImpl<MCFixup> &Fixups,
337                      const MCSubtargetInfo &STI) const {
338 
339   const MCOperand &MO = MI.getOperand(OpNo);
340   // If the destination is an immediate, divide by 4.
341   if (MO.isImm()) return MO.getImm()>>2;
342 
343   assert(MO.isExpr() &&
344          "getJumpTargetOpValue expects only expressions or an immediate");
345 
346   const MCExpr *Expr = MO.getExpr();
347   Fixups.push_back(MCFixup::Create(0, Expr,
348                                    MCFixupKind(Mips::fixup_Mips_26)));
349   return 0;
350 }
351 
352 unsigned MipsMCCodeEmitter::
getJumpTargetOpValueMM(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const353 getJumpTargetOpValueMM(const MCInst &MI, unsigned OpNo,
354                        SmallVectorImpl<MCFixup> &Fixups,
355                        const MCSubtargetInfo &STI) const {
356 
357   const MCOperand &MO = MI.getOperand(OpNo);
358   // If the destination is an immediate, divide by 2.
359   if (MO.isImm()) return MO.getImm() >> 1;
360 
361   assert(MO.isExpr() &&
362          "getJumpTargetOpValueMM expects only expressions or an immediate");
363 
364   const MCExpr *Expr = MO.getExpr();
365   Fixups.push_back(MCFixup::Create(0, Expr,
366                                    MCFixupKind(Mips::fixup_MICROMIPS_26_S1)));
367   return 0;
368 }
369 
370 unsigned MipsMCCodeEmitter::
getUImm5Lsl2Encoding(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const371 getUImm5Lsl2Encoding(const MCInst &MI, unsigned OpNo,
372                      SmallVectorImpl<MCFixup> &Fixups,
373                      const MCSubtargetInfo &STI) const {
374 
375   const MCOperand &MO = MI.getOperand(OpNo);
376   if (MO.isImm()) {
377     // The immediate is encoded as 'immediate << 2'.
378     unsigned Res = getMachineOpValue(MI, MO, Fixups, STI);
379     assert((Res & 3) == 0);
380     return Res >> 2;
381   }
382 
383   assert(MO.isExpr() &&
384          "getUImm5Lsl2Encoding expects only expressions or an immediate");
385 
386   return 0;
387 }
388 
389 unsigned MipsMCCodeEmitter::
getSImm3Lsa2Value(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const390 getSImm3Lsa2Value(const MCInst &MI, unsigned OpNo,
391                   SmallVectorImpl<MCFixup> &Fixups,
392                   const MCSubtargetInfo &STI) const {
393 
394   const MCOperand &MO = MI.getOperand(OpNo);
395   if (MO.isImm()) {
396     int Value = MO.getImm();
397     return Value >> 2;
398   }
399 
400   return 0;
401 }
402 
403 unsigned MipsMCCodeEmitter::
getUImm6Lsl2Encoding(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const404 getUImm6Lsl2Encoding(const MCInst &MI, unsigned OpNo,
405                      SmallVectorImpl<MCFixup> &Fixups,
406                      const MCSubtargetInfo &STI) const {
407 
408   const MCOperand &MO = MI.getOperand(OpNo);
409   if (MO.isImm()) {
410     unsigned Value = MO.getImm();
411     return Value >> 2;
412   }
413 
414   return 0;
415 }
416 
417 unsigned MipsMCCodeEmitter::
getSImm9AddiuspValue(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const418 getSImm9AddiuspValue(const MCInst &MI, unsigned OpNo,
419                      SmallVectorImpl<MCFixup> &Fixups,
420                      const MCSubtargetInfo &STI) const {
421 
422   const MCOperand &MO = MI.getOperand(OpNo);
423   if (MO.isImm()) {
424     unsigned Binary = (MO.getImm() >> 2) & 0x0000ffff;
425     return (((Binary & 0x8000) >> 7) | (Binary & 0x00ff));
426   }
427 
428   return 0;
429 }
430 
431 unsigned MipsMCCodeEmitter::
getExprOpValue(const MCExpr * Expr,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const432 getExprOpValue(const MCExpr *Expr,SmallVectorImpl<MCFixup> &Fixups,
433                const MCSubtargetInfo &STI) const {
434   int64_t Res;
435 
436   if (Expr->EvaluateAsAbsolute(Res))
437     return Res;
438 
439   MCExpr::ExprKind Kind = Expr->getKind();
440   if (Kind == MCExpr::Constant) {
441     return cast<MCConstantExpr>(Expr)->getValue();
442   }
443 
444   if (Kind == MCExpr::Binary) {
445     unsigned Res = getExprOpValue(cast<MCBinaryExpr>(Expr)->getLHS(), Fixups, STI);
446     Res += getExprOpValue(cast<MCBinaryExpr>(Expr)->getRHS(), Fixups, STI);
447     return Res;
448   }
449 
450   if (Kind == MCExpr::Target) {
451     const MipsMCExpr *MipsExpr = cast<MipsMCExpr>(Expr);
452 
453     Mips::Fixups FixupKind = Mips::Fixups(0);
454     switch (MipsExpr->getKind()) {
455     default: llvm_unreachable("Unsupported fixup kind for target expression!");
456     case MipsMCExpr::VK_Mips_HIGHEST:
457       FixupKind = Mips::fixup_Mips_HIGHEST;
458       break;
459     case MipsMCExpr::VK_Mips_HIGHER:
460       FixupKind = Mips::fixup_Mips_HIGHER;
461       break;
462     case MipsMCExpr::VK_Mips_HI:
463       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_HI16
464                                    : Mips::fixup_Mips_HI16;
465       break;
466     case MipsMCExpr::VK_Mips_LO:
467       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_LO16
468                                    : Mips::fixup_Mips_LO16;
469       break;
470     }
471     Fixups.push_back(MCFixup::Create(0, MipsExpr, MCFixupKind(FixupKind)));
472     return 0;
473   }
474 
475   if (Kind == MCExpr::SymbolRef) {
476     Mips::Fixups FixupKind = Mips::Fixups(0);
477 
478     switch(cast<MCSymbolRefExpr>(Expr)->getKind()) {
479     default: llvm_unreachable("Unknown fixup kind!");
480       break;
481     case MCSymbolRefExpr::VK_Mips_GPOFF_HI :
482       FixupKind = Mips::fixup_Mips_GPOFF_HI;
483       break;
484     case MCSymbolRefExpr::VK_Mips_GPOFF_LO :
485       FixupKind = Mips::fixup_Mips_GPOFF_LO;
486       break;
487     case MCSymbolRefExpr::VK_Mips_GOT_PAGE :
488       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_GOT_PAGE
489                               : Mips::fixup_Mips_GOT_PAGE;
490       break;
491     case MCSymbolRefExpr::VK_Mips_GOT_OFST :
492       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_GOT_OFST
493                               : Mips::fixup_Mips_GOT_OFST;
494       break;
495     case MCSymbolRefExpr::VK_Mips_GOT_DISP :
496       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_GOT_DISP
497                               : Mips::fixup_Mips_GOT_DISP;
498       break;
499     case MCSymbolRefExpr::VK_Mips_GPREL:
500       FixupKind = Mips::fixup_Mips_GPREL16;
501       break;
502     case MCSymbolRefExpr::VK_Mips_GOT_CALL:
503       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_CALL16
504                               : Mips::fixup_Mips_CALL16;
505       break;
506     case MCSymbolRefExpr::VK_Mips_GOT16:
507       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_GOT16
508                               : Mips::fixup_Mips_GOT_Global;
509       break;
510     case MCSymbolRefExpr::VK_Mips_GOT:
511       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_GOT16
512                               : Mips::fixup_Mips_GOT_Local;
513       break;
514     case MCSymbolRefExpr::VK_Mips_ABS_HI:
515       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_HI16
516                               : Mips::fixup_Mips_HI16;
517       break;
518     case MCSymbolRefExpr::VK_Mips_ABS_LO:
519       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_LO16
520                               : Mips::fixup_Mips_LO16;
521       break;
522     case MCSymbolRefExpr::VK_Mips_TLSGD:
523       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_GD
524                               : Mips::fixup_Mips_TLSGD;
525       break;
526     case MCSymbolRefExpr::VK_Mips_TLSLDM:
527       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_LDM
528                               : Mips::fixup_Mips_TLSLDM;
529       break;
530     case MCSymbolRefExpr::VK_Mips_DTPREL_HI:
531       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_DTPREL_HI16
532                               : Mips::fixup_Mips_DTPREL_HI;
533       break;
534     case MCSymbolRefExpr::VK_Mips_DTPREL_LO:
535       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_DTPREL_LO16
536                               : Mips::fixup_Mips_DTPREL_LO;
537       break;
538     case MCSymbolRefExpr::VK_Mips_GOTTPREL:
539       FixupKind = Mips::fixup_Mips_GOTTPREL;
540       break;
541     case MCSymbolRefExpr::VK_Mips_TPREL_HI:
542       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_TPREL_HI16
543                               : Mips::fixup_Mips_TPREL_HI;
544       break;
545     case MCSymbolRefExpr::VK_Mips_TPREL_LO:
546       FixupKind = isMicroMips(STI) ? Mips::fixup_MICROMIPS_TLS_TPREL_LO16
547                               : Mips::fixup_Mips_TPREL_LO;
548       break;
549     case MCSymbolRefExpr::VK_Mips_HIGHER:
550       FixupKind = Mips::fixup_Mips_HIGHER;
551       break;
552     case MCSymbolRefExpr::VK_Mips_HIGHEST:
553       FixupKind = Mips::fixup_Mips_HIGHEST;
554       break;
555     case MCSymbolRefExpr::VK_Mips_GOT_HI16:
556       FixupKind = Mips::fixup_Mips_GOT_HI16;
557       break;
558     case MCSymbolRefExpr::VK_Mips_GOT_LO16:
559       FixupKind = Mips::fixup_Mips_GOT_LO16;
560       break;
561     case MCSymbolRefExpr::VK_Mips_CALL_HI16:
562       FixupKind = Mips::fixup_Mips_CALL_HI16;
563       break;
564     case MCSymbolRefExpr::VK_Mips_CALL_LO16:
565       FixupKind = Mips::fixup_Mips_CALL_LO16;
566       break;
567     case MCSymbolRefExpr::VK_Mips_PCREL_HI16:
568       FixupKind = Mips::fixup_MIPS_PCHI16;
569       break;
570     case MCSymbolRefExpr::VK_Mips_PCREL_LO16:
571       FixupKind = Mips::fixup_MIPS_PCLO16;
572       break;
573     } // switch
574 
575     Fixups.push_back(MCFixup::Create(0, Expr, MCFixupKind(FixupKind)));
576     return 0;
577   }
578   return 0;
579 }
580 
581 /// getMachineOpValue - Return binary encoding of operand. If the machine
582 /// operand requires relocation, record the relocation and return zero.
583 unsigned MipsMCCodeEmitter::
getMachineOpValue(const MCInst & MI,const MCOperand & MO,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const584 getMachineOpValue(const MCInst &MI, const MCOperand &MO,
585                   SmallVectorImpl<MCFixup> &Fixups,
586                   const MCSubtargetInfo &STI) const {
587   if (MO.isReg()) {
588     unsigned Reg = MO.getReg();
589     unsigned RegNo = Ctx.getRegisterInfo()->getEncodingValue(Reg);
590     return RegNo;
591   } else if (MO.isImm()) {
592     return static_cast<unsigned>(MO.getImm());
593   } else if (MO.isFPImm()) {
594     return static_cast<unsigned>(APFloat(MO.getFPImm())
595         .bitcastToAPInt().getHiBits(32).getLimitedValue());
596   }
597   // MO must be an Expr.
598   assert(MO.isExpr());
599   return getExprOpValue(MO.getExpr(),Fixups, STI);
600 }
601 
602 /// getMSAMemEncoding - Return binary encoding of memory operand for LD/ST
603 /// instructions.
604 unsigned
getMSAMemEncoding(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const605 MipsMCCodeEmitter::getMSAMemEncoding(const MCInst &MI, unsigned OpNo,
606                                      SmallVectorImpl<MCFixup> &Fixups,
607                                      const MCSubtargetInfo &STI) const {
608   // Base register is encoded in bits 20-16, offset is encoded in bits 15-0.
609   assert(MI.getOperand(OpNo).isReg());
610   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo),Fixups, STI) << 16;
611   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI);
612 
613   // The immediate field of an LD/ST instruction is scaled which means it must
614   // be divided (when encoding) by the size (in bytes) of the instructions'
615   // data format.
616   // .b - 1 byte
617   // .h - 2 bytes
618   // .w - 4 bytes
619   // .d - 8 bytes
620   switch(MI.getOpcode())
621   {
622   default:
623     assert (0 && "Unexpected instruction");
624     break;
625   case Mips::LD_B:
626   case Mips::ST_B:
627     // We don't need to scale the offset in this case
628     break;
629   case Mips::LD_H:
630   case Mips::ST_H:
631     OffBits >>= 1;
632     break;
633   case Mips::LD_W:
634   case Mips::ST_W:
635     OffBits >>= 2;
636     break;
637   case Mips::LD_D:
638   case Mips::ST_D:
639     OffBits >>= 3;
640     break;
641   }
642 
643   return (OffBits & 0xFFFF) | RegBits;
644 }
645 
646 /// getMemEncoding - Return binary encoding of memory related operand.
647 /// If the offset operand requires relocation, record the relocation.
648 unsigned
getMemEncoding(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const649 MipsMCCodeEmitter::getMemEncoding(const MCInst &MI, unsigned OpNo,
650                                   SmallVectorImpl<MCFixup> &Fixups,
651                                   const MCSubtargetInfo &STI) const {
652   // Base register is encoded in bits 20-16, offset is encoded in bits 15-0.
653   assert(MI.getOperand(OpNo).isReg());
654   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo),Fixups, STI) << 16;
655   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI);
656 
657   return (OffBits & 0xFFFF) | RegBits;
658 }
659 
660 unsigned MipsMCCodeEmitter::
getMemEncodingMMImm4(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const661 getMemEncodingMMImm4(const MCInst &MI, unsigned OpNo,
662                      SmallVectorImpl<MCFixup> &Fixups,
663                      const MCSubtargetInfo &STI) const {
664   // Base register is encoded in bits 6-4, offset is encoded in bits 3-0.
665   assert(MI.getOperand(OpNo).isReg());
666   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo),
667                                        Fixups, STI) << 4;
668   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1),
669                                        Fixups, STI);
670 
671   return (OffBits & 0xF) | RegBits;
672 }
673 
674 unsigned MipsMCCodeEmitter::
getMemEncodingMMImm4Lsl1(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const675 getMemEncodingMMImm4Lsl1(const MCInst &MI, unsigned OpNo,
676                          SmallVectorImpl<MCFixup> &Fixups,
677                          const MCSubtargetInfo &STI) const {
678   // Base register is encoded in bits 6-4, offset is encoded in bits 3-0.
679   assert(MI.getOperand(OpNo).isReg());
680   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo),
681                                        Fixups, STI) << 4;
682   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1),
683                                        Fixups, STI) >> 1;
684 
685   return (OffBits & 0xF) | RegBits;
686 }
687 
688 unsigned MipsMCCodeEmitter::
getMemEncodingMMImm4Lsl2(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const689 getMemEncodingMMImm4Lsl2(const MCInst &MI, unsigned OpNo,
690                          SmallVectorImpl<MCFixup> &Fixups,
691                          const MCSubtargetInfo &STI) const {
692   // Base register is encoded in bits 6-4, offset is encoded in bits 3-0.
693   assert(MI.getOperand(OpNo).isReg());
694   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo),
695                                        Fixups, STI) << 4;
696   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1),
697                                        Fixups, STI) >> 2;
698 
699   return (OffBits & 0xF) | RegBits;
700 }
701 
702 unsigned MipsMCCodeEmitter::
getMemEncodingMMSPImm5Lsl2(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const703 getMemEncodingMMSPImm5Lsl2(const MCInst &MI, unsigned OpNo,
704                            SmallVectorImpl<MCFixup> &Fixups,
705                            const MCSubtargetInfo &STI) const {
706   // Register is encoded in bits 9-5, offset is encoded in bits 4-0.
707   assert(MI.getOperand(OpNo).isReg() &&
708          MI.getOperand(OpNo).getReg() == Mips::SP &&
709          "Unexpected base register!");
710   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1),
711                                        Fixups, STI) >> 2;
712 
713   return OffBits & 0x1F;
714 }
715 
716 unsigned MipsMCCodeEmitter::
getMemEncodingMMImm12(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const717 getMemEncodingMMImm12(const MCInst &MI, unsigned OpNo,
718                       SmallVectorImpl<MCFixup> &Fixups,
719                       const MCSubtargetInfo &STI) const {
720   // opNum can be invalid if instruction had reglist as operand.
721   // MemOperand is always last operand of instruction (base + offset).
722   switch (MI.getOpcode()) {
723   default:
724     break;
725   case Mips::SWM32_MM:
726   case Mips::LWM32_MM:
727     OpNo = MI.getNumOperands() - 2;
728     break;
729   }
730 
731   // Base register is encoded in bits 20-16, offset is encoded in bits 11-0.
732   assert(MI.getOperand(OpNo).isReg());
733   unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI) << 16;
734   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI);
735 
736   return (OffBits & 0x0FFF) | RegBits;
737 }
738 
739 unsigned MipsMCCodeEmitter::
getMemEncodingMMImm4sp(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const740 getMemEncodingMMImm4sp(const MCInst &MI, unsigned OpNo,
741                        SmallVectorImpl<MCFixup> &Fixups,
742                        const MCSubtargetInfo &STI) const {
743   // opNum can be invalid if instruction had reglist as operand
744   // MemOperand is always last operand of instruction (base + offset)
745   switch (MI.getOpcode()) {
746   default:
747     break;
748   case Mips::SWM16_MM:
749   case Mips::LWM16_MM:
750     OpNo = MI.getNumOperands() - 2;
751     break;
752   }
753 
754   // Offset is encoded in bits 4-0.
755   assert(MI.getOperand(OpNo).isReg());
756   // Base register is always SP - thus it is not encoded.
757   assert(MI.getOperand(OpNo+1).isImm());
758   unsigned OffBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups, STI);
759 
760   return ((OffBits >> 2) & 0x0F);
761 }
762 
763 unsigned
getSizeExtEncoding(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const764 MipsMCCodeEmitter::getSizeExtEncoding(const MCInst &MI, unsigned OpNo,
765                                       SmallVectorImpl<MCFixup> &Fixups,
766                                       const MCSubtargetInfo &STI) const {
767   assert(MI.getOperand(OpNo).isImm());
768   unsigned SizeEncoding = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI);
769   return SizeEncoding - 1;
770 }
771 
772 // FIXME: should be called getMSBEncoding
773 //
774 unsigned
getSizeInsEncoding(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const775 MipsMCCodeEmitter::getSizeInsEncoding(const MCInst &MI, unsigned OpNo,
776                                       SmallVectorImpl<MCFixup> &Fixups,
777                                       const MCSubtargetInfo &STI) const {
778   assert(MI.getOperand(OpNo-1).isImm());
779   assert(MI.getOperand(OpNo).isImm());
780   unsigned Position = getMachineOpValue(MI, MI.getOperand(OpNo-1), Fixups, STI);
781   unsigned Size = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI);
782 
783   return Position + Size - 1;
784 }
785 
786 unsigned
getLSAImmEncoding(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const787 MipsMCCodeEmitter::getLSAImmEncoding(const MCInst &MI, unsigned OpNo,
788                                      SmallVectorImpl<MCFixup> &Fixups,
789                                      const MCSubtargetInfo &STI) const {
790   assert(MI.getOperand(OpNo).isImm());
791   // The immediate is encoded as 'immediate - 1'.
792   return getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI) - 1;
793 }
794 
795 unsigned
getSimm19Lsl2Encoding(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const796 MipsMCCodeEmitter::getSimm19Lsl2Encoding(const MCInst &MI, unsigned OpNo,
797                                          SmallVectorImpl<MCFixup> &Fixups,
798                                          const MCSubtargetInfo &STI) const {
799   const MCOperand &MO = MI.getOperand(OpNo);
800   if (MO.isImm()) {
801     // The immediate is encoded as 'immediate << 2'.
802     unsigned Res = getMachineOpValue(MI, MO, Fixups, STI);
803     assert((Res & 3) == 0);
804     return Res >> 2;
805   }
806 
807   assert(MO.isExpr() &&
808          "getSimm19Lsl2Encoding expects only expressions or an immediate");
809 
810   const MCExpr *Expr = MO.getExpr();
811   Fixups.push_back(MCFixup::Create(0, Expr,
812                                    MCFixupKind(Mips::fixup_MIPS_PC19_S2)));
813   return 0;
814 }
815 
816 unsigned
getSimm18Lsl3Encoding(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const817 MipsMCCodeEmitter::getSimm18Lsl3Encoding(const MCInst &MI, unsigned OpNo,
818                                          SmallVectorImpl<MCFixup> &Fixups,
819                                          const MCSubtargetInfo &STI) const {
820   const MCOperand &MO = MI.getOperand(OpNo);
821   if (MO.isImm()) {
822     // The immediate is encoded as 'immediate << 3'.
823     unsigned Res = getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI);
824     assert((Res & 7) == 0);
825     return Res >> 3;
826   }
827 
828   assert(MO.isExpr() &&
829          "getSimm18Lsl2Encoding expects only expressions or an immediate");
830 
831   const MCExpr *Expr = MO.getExpr();
832   Fixups.push_back(MCFixup::Create(0, Expr,
833                                    MCFixupKind(Mips::fixup_MIPS_PC18_S3)));
834   return 0;
835 }
836 
837 unsigned
getUImm3Mod8Encoding(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const838 MipsMCCodeEmitter::getUImm3Mod8Encoding(const MCInst &MI, unsigned OpNo,
839                                         SmallVectorImpl<MCFixup> &Fixups,
840                                         const MCSubtargetInfo &STI) const {
841   assert(MI.getOperand(OpNo).isImm());
842   const MCOperand &MO = MI.getOperand(OpNo);
843   return MO.getImm() % 8;
844 }
845 
846 unsigned
getUImm4AndValue(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const847 MipsMCCodeEmitter::getUImm4AndValue(const MCInst &MI, unsigned OpNo,
848                                     SmallVectorImpl<MCFixup> &Fixups,
849                                     const MCSubtargetInfo &STI) const {
850   assert(MI.getOperand(OpNo).isImm());
851   const MCOperand &MO = MI.getOperand(OpNo);
852   unsigned Value = MO.getImm();
853   switch (Value) {
854     case 128:   return 0x0;
855     case 1:     return 0x1;
856     case 2:     return 0x2;
857     case 3:     return 0x3;
858     case 4:     return 0x4;
859     case 7:     return 0x5;
860     case 8:     return 0x6;
861     case 15:    return 0x7;
862     case 16:    return 0x8;
863     case 31:    return 0x9;
864     case 32:    return 0xa;
865     case 63:    return 0xb;
866     case 64:    return 0xc;
867     case 255:   return 0xd;
868     case 32768: return 0xe;
869     case 65535: return 0xf;
870   }
871   llvm_unreachable("Unexpected value");
872 }
873 
874 unsigned
getRegisterListOpValue(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const875 MipsMCCodeEmitter::getRegisterListOpValue(const MCInst &MI, unsigned OpNo,
876                                           SmallVectorImpl<MCFixup> &Fixups,
877                                           const MCSubtargetInfo &STI) const {
878   unsigned res = 0;
879 
880   // Register list operand is always first operand of instruction and it is
881   // placed before memory operand (register + imm).
882 
883   for (unsigned I = OpNo, E = MI.getNumOperands() - 2; I < E; ++I) {
884     unsigned Reg = MI.getOperand(I).getReg();
885     unsigned RegNo = Ctx.getRegisterInfo()->getEncodingValue(Reg);
886     if (RegNo != 31)
887       res++;
888     else
889       res |= 0x10;
890   }
891   return res;
892 }
893 
894 unsigned
getRegisterListOpValue16(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const895 MipsMCCodeEmitter::getRegisterListOpValue16(const MCInst &MI, unsigned OpNo,
896                                             SmallVectorImpl<MCFixup> &Fixups,
897                                             const MCSubtargetInfo &STI) const {
898   return (MI.getNumOperands() - 4);
899 }
900 
901 unsigned
getRegisterPairOpValue(const MCInst & MI,unsigned OpNo,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const902 MipsMCCodeEmitter::getRegisterPairOpValue(const MCInst &MI, unsigned OpNo,
903                                           SmallVectorImpl<MCFixup> &Fixups,
904                                           const MCSubtargetInfo &STI) const {
905   return getMachineOpValue(MI, MI.getOperand(OpNo), Fixups, STI);
906 }
907 
908 #include "MipsGenMCCodeEmitter.inc"
909