1 //=- AArch64/AArch64MCCodeEmitter.cpp - Convert AArch64 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 AArch64MCCodeEmitter class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "MCTargetDesc/AArch64AddressingModes.h"
15 #include "MCTargetDesc/AArch64FixupKinds.h"
16 #include "MCTargetDesc/AArch64MCExpr.h"
17 #include "Utils/AArch64BaseInfo.h"
18 #include "llvm/ADT/Statistic.h"
19 #include "llvm/MC/MCCodeEmitter.h"
20 #include "llvm/MC/MCContext.h"
21 #include "llvm/MC/MCInst.h"
22 #include "llvm/MC/MCInstrInfo.h"
23 #include "llvm/MC/MCRegisterInfo.h"
24 #include "llvm/MC/MCSubtargetInfo.h"
25 #include "llvm/Support/raw_ostream.h"
26 using namespace llvm;
27 
28 #define DEBUG_TYPE "mccodeemitter"
29 
30 STATISTIC(MCNumEmitted, "Number of MC instructions emitted.");
31 STATISTIC(MCNumFixups, "Number of MC fixups created.");
32 
33 namespace {
34 
35 class AArch64MCCodeEmitter : public MCCodeEmitter {
36   MCContext &Ctx;
37 
38   AArch64MCCodeEmitter(const AArch64MCCodeEmitter &); // DO NOT IMPLEMENT
39   void operator=(const AArch64MCCodeEmitter &);     // DO NOT IMPLEMENT
40 public:
AArch64MCCodeEmitter(const MCInstrInfo & mcii,MCContext & ctx)41   AArch64MCCodeEmitter(const MCInstrInfo &mcii, MCContext &ctx) : Ctx(ctx) {}
42 
~AArch64MCCodeEmitter()43   ~AArch64MCCodeEmitter() override {}
44 
45   // getBinaryCodeForInstr - TableGen'erated function for getting the
46   // binary encoding for an instruction.
47   uint64_t getBinaryCodeForInstr(const MCInst &MI,
48                                  SmallVectorImpl<MCFixup> &Fixups,
49                                  const MCSubtargetInfo &STI) const;
50 
51   /// getMachineOpValue - Return binary encoding of operand. If the machine
52   /// operand requires relocation, record the relocation and return zero.
53   unsigned getMachineOpValue(const MCInst &MI, const MCOperand &MO,
54                              SmallVectorImpl<MCFixup> &Fixups,
55                              const MCSubtargetInfo &STI) const;
56 
57   /// getLdStUImm12OpValue - Return encoding info for 12-bit unsigned immediate
58   /// attached to a load, store or prfm instruction. If operand requires a
59   /// relocation, record it and return zero in that part of the encoding.
60   template <uint32_t FixupKind>
61   uint32_t getLdStUImm12OpValue(const MCInst &MI, unsigned OpIdx,
62                                 SmallVectorImpl<MCFixup> &Fixups,
63                                 const MCSubtargetInfo &STI) const;
64 
65   /// getAdrLabelOpValue - Return encoding info for 21-bit immediate ADR label
66   /// target.
67   uint32_t getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
68                               SmallVectorImpl<MCFixup> &Fixups,
69                               const MCSubtargetInfo &STI) const;
70 
71   /// getAddSubImmOpValue - Return encoding for the 12-bit immediate value and
72   /// the 2-bit shift field.
73   uint32_t getAddSubImmOpValue(const MCInst &MI, unsigned OpIdx,
74                                SmallVectorImpl<MCFixup> &Fixups,
75                                const MCSubtargetInfo &STI) const;
76 
77   /// getCondBranchTargetOpValue - Return the encoded value for a conditional
78   /// branch target.
79   uint32_t getCondBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
80                                       SmallVectorImpl<MCFixup> &Fixups,
81                                       const MCSubtargetInfo &STI) const;
82 
83   /// getLoadLiteralOpValue - Return the encoded value for a load-literal
84   /// pc-relative address.
85   uint32_t getLoadLiteralOpValue(const MCInst &MI, unsigned OpIdx,
86                                  SmallVectorImpl<MCFixup> &Fixups,
87                                  const MCSubtargetInfo &STI) const;
88 
89   /// getMemExtendOpValue - Return the encoded value for a reg-extend load/store
90   /// instruction: bit 0 is whether a shift is present, bit 1 is whether the
91   /// operation is a sign extend (as opposed to a zero extend).
92   uint32_t getMemExtendOpValue(const MCInst &MI, unsigned OpIdx,
93                                SmallVectorImpl<MCFixup> &Fixups,
94                                const MCSubtargetInfo &STI) const;
95 
96   /// getTestBranchTargetOpValue - Return the encoded value for a test-bit-and-
97   /// branch target.
98   uint32_t getTestBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
99                                       SmallVectorImpl<MCFixup> &Fixups,
100                                       const MCSubtargetInfo &STI) const;
101 
102   /// getBranchTargetOpValue - Return the encoded value for an unconditional
103   /// branch target.
104   uint32_t getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
105                                   SmallVectorImpl<MCFixup> &Fixups,
106                                   const MCSubtargetInfo &STI) const;
107 
108   /// getMoveWideImmOpValue - Return the encoded value for the immediate operand
109   /// of a MOVZ or MOVK instruction.
110   uint32_t getMoveWideImmOpValue(const MCInst &MI, unsigned OpIdx,
111                                  SmallVectorImpl<MCFixup> &Fixups,
112                                  const MCSubtargetInfo &STI) const;
113 
114   /// getVecShifterOpValue - Return the encoded value for the vector shifter.
115   uint32_t getVecShifterOpValue(const MCInst &MI, unsigned OpIdx,
116                                 SmallVectorImpl<MCFixup> &Fixups,
117                                 const MCSubtargetInfo &STI) const;
118 
119   /// getMoveVecShifterOpValue - Return the encoded value for the vector move
120   /// shifter (MSL).
121   uint32_t getMoveVecShifterOpValue(const MCInst &MI, unsigned OpIdx,
122                                     SmallVectorImpl<MCFixup> &Fixups,
123                                     const MCSubtargetInfo &STI) const;
124 
125   /// getFixedPointScaleOpValue - Return the encoded value for the
126   // FP-to-fixed-point scale factor.
127   uint32_t getFixedPointScaleOpValue(const MCInst &MI, unsigned OpIdx,
128                                      SmallVectorImpl<MCFixup> &Fixups,
129                                      const MCSubtargetInfo &STI) const;
130 
131   uint32_t getVecShiftR64OpValue(const MCInst &MI, unsigned OpIdx,
132                                  SmallVectorImpl<MCFixup> &Fixups,
133                                  const MCSubtargetInfo &STI) const;
134   uint32_t getVecShiftR32OpValue(const MCInst &MI, unsigned OpIdx,
135                                  SmallVectorImpl<MCFixup> &Fixups,
136                                  const MCSubtargetInfo &STI) const;
137   uint32_t getVecShiftR16OpValue(const MCInst &MI, unsigned OpIdx,
138                                  SmallVectorImpl<MCFixup> &Fixups,
139                                  const MCSubtargetInfo &STI) const;
140   uint32_t getVecShiftR8OpValue(const MCInst &MI, unsigned OpIdx,
141                                 SmallVectorImpl<MCFixup> &Fixups,
142                                 const MCSubtargetInfo &STI) const;
143   uint32_t getVecShiftL64OpValue(const MCInst &MI, unsigned OpIdx,
144                                  SmallVectorImpl<MCFixup> &Fixups,
145                                  const MCSubtargetInfo &STI) const;
146   uint32_t getVecShiftL32OpValue(const MCInst &MI, unsigned OpIdx,
147                                  SmallVectorImpl<MCFixup> &Fixups,
148                                  const MCSubtargetInfo &STI) const;
149   uint32_t getVecShiftL16OpValue(const MCInst &MI, unsigned OpIdx,
150                                  SmallVectorImpl<MCFixup> &Fixups,
151                                  const MCSubtargetInfo &STI) const;
152   uint32_t getVecShiftL8OpValue(const MCInst &MI, unsigned OpIdx,
153                                 SmallVectorImpl<MCFixup> &Fixups,
154                                 const MCSubtargetInfo &STI) const;
155 
156   /// getSIMDShift64OpValue - Return the encoded value for the
157   // shift-by-immediate AdvSIMD instructions.
158   uint32_t getSIMDShift64OpValue(const MCInst &MI, unsigned OpIdx,
159                                  SmallVectorImpl<MCFixup> &Fixups,
160                                  const MCSubtargetInfo &STI) const;
161 
162   uint32_t getSIMDShift64_32OpValue(const MCInst &MI, unsigned OpIdx,
163                                     SmallVectorImpl<MCFixup> &Fixups,
164                                     const MCSubtargetInfo &STI) const;
165 
166   uint32_t getSIMDShift32OpValue(const MCInst &MI, unsigned OpIdx,
167                                  SmallVectorImpl<MCFixup> &Fixups,
168                                  const MCSubtargetInfo &STI) const;
169 
170   uint32_t getSIMDShift16OpValue(const MCInst &MI, unsigned OpIdx,
171                                  SmallVectorImpl<MCFixup> &Fixups,
172                                  const MCSubtargetInfo &STI) const;
173 
174   unsigned fixMOVZ(const MCInst &MI, unsigned EncodedValue,
175                    const MCSubtargetInfo &STI) const;
176 
EmitByte(unsigned char C,raw_ostream & OS) const177   void EmitByte(unsigned char C, raw_ostream &OS) const { OS << (char)C; }
178 
EmitConstant(uint64_t Val,unsigned Size,raw_ostream & OS) const179   void EmitConstant(uint64_t Val, unsigned Size, raw_ostream &OS) const {
180     // Output the constant in little endian byte order.
181     for (unsigned i = 0; i != Size; ++i) {
182       EmitByte(Val & 255, OS);
183       Val >>= 8;
184     }
185   }
186 
187   void EncodeInstruction(const MCInst &MI, raw_ostream &OS,
188                          SmallVectorImpl<MCFixup> &Fixups,
189                          const MCSubtargetInfo &STI) const override;
190 
191   unsigned fixMulHigh(const MCInst &MI, unsigned EncodedValue,
192                       const MCSubtargetInfo &STI) const;
193 
194   template<int hasRs, int hasRt2> unsigned
195   fixLoadStoreExclusive(const MCInst &MI, unsigned EncodedValue,
196                         const MCSubtargetInfo &STI) const;
197 
198   unsigned fixOneOperandFPComparison(const MCInst &MI, unsigned EncodedValue,
199                                      const MCSubtargetInfo &STI) const;
200 };
201 
202 } // end anonymous namespace
203 
createAArch64MCCodeEmitter(const MCInstrInfo & MCII,const MCRegisterInfo & MRI,MCContext & Ctx)204 MCCodeEmitter *llvm::createAArch64MCCodeEmitter(const MCInstrInfo &MCII,
205                                                 const MCRegisterInfo &MRI,
206                                                 MCContext &Ctx) {
207   return new AArch64MCCodeEmitter(MCII, Ctx);
208 }
209 
210 /// getMachineOpValue - Return binary encoding of operand. If the machine
211 /// operand requires relocation, record the relocation and return zero.
212 unsigned
getMachineOpValue(const MCInst & MI,const MCOperand & MO,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const213 AArch64MCCodeEmitter::getMachineOpValue(const MCInst &MI, const MCOperand &MO,
214                                         SmallVectorImpl<MCFixup> &Fixups,
215                                         const MCSubtargetInfo &STI) const {
216   if (MO.isReg())
217     return Ctx.getRegisterInfo()->getEncodingValue(MO.getReg());
218 
219   assert(MO.isImm() && "did not expect relocated expression");
220   return static_cast<unsigned>(MO.getImm());
221 }
222 
223 template<unsigned FixupKind> uint32_t
getLdStUImm12OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const224 AArch64MCCodeEmitter::getLdStUImm12OpValue(const MCInst &MI, unsigned OpIdx,
225                                            SmallVectorImpl<MCFixup> &Fixups,
226                                            const MCSubtargetInfo &STI) const {
227   const MCOperand &MO = MI.getOperand(OpIdx);
228   uint32_t ImmVal = 0;
229 
230   if (MO.isImm())
231     ImmVal = static_cast<uint32_t>(MO.getImm());
232   else {
233     assert(MO.isExpr() && "unable to encode load/store imm operand");
234     MCFixupKind Kind = MCFixupKind(FixupKind);
235     Fixups.push_back(MCFixup::Create(0, MO.getExpr(), Kind, MI.getLoc()));
236     ++MCNumFixups;
237   }
238 
239   return ImmVal;
240 }
241 
242 /// getAdrLabelOpValue - Return encoding info for 21-bit immediate ADR label
243 /// target.
244 uint32_t
getAdrLabelOpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const245 AArch64MCCodeEmitter::getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
246                                          SmallVectorImpl<MCFixup> &Fixups,
247                                          const MCSubtargetInfo &STI) const {
248   const MCOperand &MO = MI.getOperand(OpIdx);
249 
250   // If the destination is an immediate, we have nothing to do.
251   if (MO.isImm())
252     return MO.getImm();
253   assert(MO.isExpr() && "Unexpected target type!");
254   const MCExpr *Expr = MO.getExpr();
255 
256   MCFixupKind Kind = MI.getOpcode() == AArch64::ADR
257                          ? MCFixupKind(AArch64::fixup_aarch64_pcrel_adr_imm21)
258                          : MCFixupKind(AArch64::fixup_aarch64_pcrel_adrp_imm21);
259   Fixups.push_back(MCFixup::Create(0, Expr, Kind, MI.getLoc()));
260 
261   MCNumFixups += 1;
262 
263   // All of the information is in the fixup.
264   return 0;
265 }
266 
267 /// getAddSubImmOpValue - Return encoding for the 12-bit immediate value and
268 /// the 2-bit shift field.  The shift field is stored in bits 13-14 of the
269 /// return value.
270 uint32_t
getAddSubImmOpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const271 AArch64MCCodeEmitter::getAddSubImmOpValue(const MCInst &MI, unsigned OpIdx,
272                                           SmallVectorImpl<MCFixup> &Fixups,
273                                           const MCSubtargetInfo &STI) const {
274   // Suboperands are [imm, shifter].
275   const MCOperand &MO = MI.getOperand(OpIdx);
276   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
277   assert(AArch64_AM::getShiftType(MO1.getImm()) == AArch64_AM::LSL &&
278          "unexpected shift type for add/sub immediate");
279   unsigned ShiftVal = AArch64_AM::getShiftValue(MO1.getImm());
280   assert((ShiftVal == 0 || ShiftVal == 12) &&
281          "unexpected shift value for add/sub immediate");
282   if (MO.isImm())
283     return MO.getImm() | (ShiftVal == 0 ? 0 : (1 << 12));
284   assert(MO.isExpr() && "Unable to encode MCOperand!");
285   const MCExpr *Expr = MO.getExpr();
286 
287   // Encode the 12 bits of the fixup.
288   MCFixupKind Kind = MCFixupKind(AArch64::fixup_aarch64_add_imm12);
289   Fixups.push_back(MCFixup::Create(0, Expr, Kind, MI.getLoc()));
290 
291   ++MCNumFixups;
292 
293   return 0;
294 }
295 
296 /// getCondBranchTargetOpValue - Return the encoded value for a conditional
297 /// branch target.
getCondBranchTargetOpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const298 uint32_t AArch64MCCodeEmitter::getCondBranchTargetOpValue(
299     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
300     const MCSubtargetInfo &STI) const {
301   const MCOperand &MO = MI.getOperand(OpIdx);
302 
303   // If the destination is an immediate, we have nothing to do.
304   if (MO.isImm())
305     return MO.getImm();
306   assert(MO.isExpr() && "Unexpected target type!");
307 
308   MCFixupKind Kind = MCFixupKind(AArch64::fixup_aarch64_pcrel_branch19);
309   Fixups.push_back(MCFixup::Create(0, MO.getExpr(), Kind, MI.getLoc()));
310 
311   ++MCNumFixups;
312 
313   // All of the information is in the fixup.
314   return 0;
315 }
316 
317 /// getLoadLiteralOpValue - Return the encoded value for a load-literal
318 /// pc-relative address.
319 uint32_t
getLoadLiteralOpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const320 AArch64MCCodeEmitter::getLoadLiteralOpValue(const MCInst &MI, unsigned OpIdx,
321                                             SmallVectorImpl<MCFixup> &Fixups,
322                                             const MCSubtargetInfo &STI) const {
323   const MCOperand &MO = MI.getOperand(OpIdx);
324 
325   // If the destination is an immediate, we have nothing to do.
326   if (MO.isImm())
327     return MO.getImm();
328   assert(MO.isExpr() && "Unexpected target type!");
329 
330   MCFixupKind Kind = MCFixupKind(AArch64::fixup_aarch64_ldr_pcrel_imm19);
331   Fixups.push_back(MCFixup::Create(0, MO.getExpr(), Kind, MI.getLoc()));
332 
333   ++MCNumFixups;
334 
335   // All of the information is in the fixup.
336   return 0;
337 }
338 
339 uint32_t
getMemExtendOpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const340 AArch64MCCodeEmitter::getMemExtendOpValue(const MCInst &MI, unsigned OpIdx,
341                                           SmallVectorImpl<MCFixup> &Fixups,
342                                           const MCSubtargetInfo &STI) const {
343   unsigned SignExtend = MI.getOperand(OpIdx).getImm();
344   unsigned DoShift = MI.getOperand(OpIdx + 1).getImm();
345   return (SignExtend << 1) | DoShift;
346 }
347 
348 uint32_t
getMoveWideImmOpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const349 AArch64MCCodeEmitter::getMoveWideImmOpValue(const MCInst &MI, unsigned OpIdx,
350                                             SmallVectorImpl<MCFixup> &Fixups,
351                                             const MCSubtargetInfo &STI) const {
352   const MCOperand &MO = MI.getOperand(OpIdx);
353 
354   if (MO.isImm())
355     return MO.getImm();
356   assert(MO.isExpr() && "Unexpected movz/movk immediate");
357 
358   Fixups.push_back(MCFixup::Create(
359       0, MO.getExpr(), MCFixupKind(AArch64::fixup_aarch64_movw), MI.getLoc()));
360 
361   ++MCNumFixups;
362 
363   return 0;
364 }
365 
366 /// getTestBranchTargetOpValue - Return the encoded value for a test-bit-and-
367 /// branch target.
getTestBranchTargetOpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const368 uint32_t AArch64MCCodeEmitter::getTestBranchTargetOpValue(
369     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
370     const MCSubtargetInfo &STI) const {
371   const MCOperand &MO = MI.getOperand(OpIdx);
372 
373   // If the destination is an immediate, we have nothing to do.
374   if (MO.isImm())
375     return MO.getImm();
376   assert(MO.isExpr() && "Unexpected ADR target type!");
377 
378   MCFixupKind Kind = MCFixupKind(AArch64::fixup_aarch64_pcrel_branch14);
379   Fixups.push_back(MCFixup::Create(0, MO.getExpr(), Kind, MI.getLoc()));
380 
381   ++MCNumFixups;
382 
383   // All of the information is in the fixup.
384   return 0;
385 }
386 
387 /// getBranchTargetOpValue - Return the encoded value for an unconditional
388 /// branch target.
389 uint32_t
getBranchTargetOpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const390 AArch64MCCodeEmitter::getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
391                                              SmallVectorImpl<MCFixup> &Fixups,
392                                              const MCSubtargetInfo &STI) const {
393   const MCOperand &MO = MI.getOperand(OpIdx);
394 
395   // If the destination is an immediate, we have nothing to do.
396   if (MO.isImm())
397     return MO.getImm();
398   assert(MO.isExpr() && "Unexpected ADR target type!");
399 
400   MCFixupKind Kind = MI.getOpcode() == AArch64::BL
401                          ? MCFixupKind(AArch64::fixup_aarch64_pcrel_call26)
402                          : MCFixupKind(AArch64::fixup_aarch64_pcrel_branch26);
403   Fixups.push_back(MCFixup::Create(0, MO.getExpr(), Kind, MI.getLoc()));
404 
405   ++MCNumFixups;
406 
407   // All of the information is in the fixup.
408   return 0;
409 }
410 
411 /// getVecShifterOpValue - Return the encoded value for the vector shifter:
412 ///
413 ///   00 -> 0
414 ///   01 -> 8
415 ///   10 -> 16
416 ///   11 -> 24
417 uint32_t
getVecShifterOpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const418 AArch64MCCodeEmitter::getVecShifterOpValue(const MCInst &MI, unsigned OpIdx,
419                                            SmallVectorImpl<MCFixup> &Fixups,
420                                            const MCSubtargetInfo &STI) const {
421   const MCOperand &MO = MI.getOperand(OpIdx);
422   assert(MO.isImm() && "Expected an immediate value for the shift amount!");
423 
424   switch (MO.getImm()) {
425   default:
426     break;
427   case 0:
428     return 0;
429   case 8:
430     return 1;
431   case 16:
432     return 2;
433   case 24:
434     return 3;
435   }
436 
437   llvm_unreachable("Invalid value for vector shift amount!");
438 }
439 
440 uint32_t
getSIMDShift64OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const441 AArch64MCCodeEmitter::getSIMDShift64OpValue(const MCInst &MI, unsigned OpIdx,
442                                             SmallVectorImpl<MCFixup> &Fixups,
443                                             const MCSubtargetInfo &STI) const {
444   const MCOperand &MO = MI.getOperand(OpIdx);
445   assert(MO.isImm() && "Expected an immediate value for the shift amount!");
446   return 64 - (MO.getImm());
447 }
448 
getSIMDShift64_32OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const449 uint32_t AArch64MCCodeEmitter::getSIMDShift64_32OpValue(
450     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
451     const MCSubtargetInfo &STI) const {
452   const MCOperand &MO = MI.getOperand(OpIdx);
453   assert(MO.isImm() && "Expected an immediate value for the shift amount!");
454   return 64 - (MO.getImm() | 32);
455 }
456 
457 uint32_t
getSIMDShift32OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const458 AArch64MCCodeEmitter::getSIMDShift32OpValue(const MCInst &MI, unsigned OpIdx,
459                                             SmallVectorImpl<MCFixup> &Fixups,
460                                             const MCSubtargetInfo &STI) const {
461   const MCOperand &MO = MI.getOperand(OpIdx);
462   assert(MO.isImm() && "Expected an immediate value for the shift amount!");
463   return 32 - (MO.getImm() | 16);
464 }
465 
466 uint32_t
getSIMDShift16OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const467 AArch64MCCodeEmitter::getSIMDShift16OpValue(const MCInst &MI, unsigned OpIdx,
468                                             SmallVectorImpl<MCFixup> &Fixups,
469                                             const MCSubtargetInfo &STI) const {
470   const MCOperand &MO = MI.getOperand(OpIdx);
471   assert(MO.isImm() && "Expected an immediate value for the shift amount!");
472   return 16 - (MO.getImm() | 8);
473 }
474 
475 /// getFixedPointScaleOpValue - Return the encoded value for the
476 // FP-to-fixed-point scale factor.
getFixedPointScaleOpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const477 uint32_t AArch64MCCodeEmitter::getFixedPointScaleOpValue(
478     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
479     const MCSubtargetInfo &STI) const {
480   const MCOperand &MO = MI.getOperand(OpIdx);
481   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
482   return 64 - MO.getImm();
483 }
484 
485 uint32_t
getVecShiftR64OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const486 AArch64MCCodeEmitter::getVecShiftR64OpValue(const MCInst &MI, unsigned OpIdx,
487                                             SmallVectorImpl<MCFixup> &Fixups,
488                                             const MCSubtargetInfo &STI) const {
489   const MCOperand &MO = MI.getOperand(OpIdx);
490   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
491   return 64 - MO.getImm();
492 }
493 
494 uint32_t
getVecShiftR32OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const495 AArch64MCCodeEmitter::getVecShiftR32OpValue(const MCInst &MI, unsigned OpIdx,
496                                             SmallVectorImpl<MCFixup> &Fixups,
497                                             const MCSubtargetInfo &STI) const {
498   const MCOperand &MO = MI.getOperand(OpIdx);
499   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
500   return 32 - MO.getImm();
501 }
502 
503 uint32_t
getVecShiftR16OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const504 AArch64MCCodeEmitter::getVecShiftR16OpValue(const MCInst &MI, unsigned OpIdx,
505                                             SmallVectorImpl<MCFixup> &Fixups,
506                                             const MCSubtargetInfo &STI) const {
507   const MCOperand &MO = MI.getOperand(OpIdx);
508   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
509   return 16 - MO.getImm();
510 }
511 
512 uint32_t
getVecShiftR8OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const513 AArch64MCCodeEmitter::getVecShiftR8OpValue(const MCInst &MI, unsigned OpIdx,
514                                            SmallVectorImpl<MCFixup> &Fixups,
515                                            const MCSubtargetInfo &STI) const {
516   const MCOperand &MO = MI.getOperand(OpIdx);
517   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
518   return 8 - MO.getImm();
519 }
520 
521 uint32_t
getVecShiftL64OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const522 AArch64MCCodeEmitter::getVecShiftL64OpValue(const MCInst &MI, unsigned OpIdx,
523                                             SmallVectorImpl<MCFixup> &Fixups,
524                                             const MCSubtargetInfo &STI) const {
525   const MCOperand &MO = MI.getOperand(OpIdx);
526   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
527   return MO.getImm() - 64;
528 }
529 
530 uint32_t
getVecShiftL32OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const531 AArch64MCCodeEmitter::getVecShiftL32OpValue(const MCInst &MI, unsigned OpIdx,
532                                             SmallVectorImpl<MCFixup> &Fixups,
533                                             const MCSubtargetInfo &STI) const {
534   const MCOperand &MO = MI.getOperand(OpIdx);
535   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
536   return MO.getImm() - 32;
537 }
538 
539 uint32_t
getVecShiftL16OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const540 AArch64MCCodeEmitter::getVecShiftL16OpValue(const MCInst &MI, unsigned OpIdx,
541                                             SmallVectorImpl<MCFixup> &Fixups,
542                                             const MCSubtargetInfo &STI) const {
543   const MCOperand &MO = MI.getOperand(OpIdx);
544   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
545   return MO.getImm() - 16;
546 }
547 
548 uint32_t
getVecShiftL8OpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const549 AArch64MCCodeEmitter::getVecShiftL8OpValue(const MCInst &MI, unsigned OpIdx,
550                                            SmallVectorImpl<MCFixup> &Fixups,
551                                            const MCSubtargetInfo &STI) const {
552   const MCOperand &MO = MI.getOperand(OpIdx);
553   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
554   return MO.getImm() - 8;
555 }
556 
557 /// getMoveVecShifterOpValue - Return the encoded value for the vector move
558 /// shifter (MSL).
getMoveVecShifterOpValue(const MCInst & MI,unsigned OpIdx,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const559 uint32_t AArch64MCCodeEmitter::getMoveVecShifterOpValue(
560     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
561     const MCSubtargetInfo &STI) const {
562   const MCOperand &MO = MI.getOperand(OpIdx);
563   assert(MO.isImm() &&
564          "Expected an immediate value for the move shift amount!");
565   unsigned ShiftVal = AArch64_AM::getShiftValue(MO.getImm());
566   assert((ShiftVal == 8 || ShiftVal == 16) && "Invalid shift amount!");
567   return ShiftVal == 8 ? 0 : 1;
568 }
569 
fixMOVZ(const MCInst & MI,unsigned EncodedValue,const MCSubtargetInfo & STI) const570 unsigned AArch64MCCodeEmitter::fixMOVZ(const MCInst &MI, unsigned EncodedValue,
571                                        const MCSubtargetInfo &STI) const {
572   // If one of the signed fixup kinds is applied to a MOVZ instruction, the
573   // eventual result could be either a MOVZ or a MOVN. It's the MCCodeEmitter's
574   // job to ensure that any bits possibly affected by this are 0. This means we
575   // must zero out bit 30 (essentially emitting a MOVN).
576   MCOperand UImm16MO = MI.getOperand(1);
577 
578   // Nothing to do if there's no fixup.
579   if (UImm16MO.isImm())
580     return EncodedValue;
581 
582   const AArch64MCExpr *A64E = cast<AArch64MCExpr>(UImm16MO.getExpr());
583   switch (A64E->getKind()) {
584   case AArch64MCExpr::VK_DTPREL_G2:
585   case AArch64MCExpr::VK_DTPREL_G1:
586   case AArch64MCExpr::VK_DTPREL_G0:
587   case AArch64MCExpr::VK_GOTTPREL_G1:
588   case AArch64MCExpr::VK_TPREL_G2:
589   case AArch64MCExpr::VK_TPREL_G1:
590   case AArch64MCExpr::VK_TPREL_G0:
591     return EncodedValue & ~(1u << 30);
592   default:
593     // Nothing to do for an unsigned fixup.
594     return EncodedValue;
595   }
596 
597 
598   return EncodedValue & ~(1u << 30);
599 }
600 
EncodeInstruction(const MCInst & MI,raw_ostream & OS,SmallVectorImpl<MCFixup> & Fixups,const MCSubtargetInfo & STI) const601 void AArch64MCCodeEmitter::EncodeInstruction(const MCInst &MI, raw_ostream &OS,
602                                              SmallVectorImpl<MCFixup> &Fixups,
603                                              const MCSubtargetInfo &STI) const {
604   if (MI.getOpcode() == AArch64::TLSDESCCALL) {
605     // This is a directive which applies an R_AARCH64_TLSDESC_CALL to the
606     // following (BLR) instruction. It doesn't emit any code itself so it
607     // doesn't go through the normal TableGenerated channels.
608     MCFixupKind Fixup = MCFixupKind(AArch64::fixup_aarch64_tlsdesc_call);
609     Fixups.push_back(MCFixup::Create(0, MI.getOperand(0).getExpr(), Fixup));
610     return;
611   }
612 
613   uint64_t Binary = getBinaryCodeForInstr(MI, Fixups, STI);
614   EmitConstant(Binary, 4, OS);
615   ++MCNumEmitted; // Keep track of the # of mi's emitted.
616 }
617 
618 unsigned
fixMulHigh(const MCInst & MI,unsigned EncodedValue,const MCSubtargetInfo & STI) const619 AArch64MCCodeEmitter::fixMulHigh(const MCInst &MI,
620                                  unsigned EncodedValue,
621                                  const MCSubtargetInfo &STI) const {
622   // The Ra field of SMULH and UMULH is unused: it should be assembled as 31
623   // (i.e. all bits 1) but is ignored by the processor.
624   EncodedValue |= 0x1f << 10;
625   return EncodedValue;
626 }
627 
628 template<int hasRs, int hasRt2> unsigned
fixLoadStoreExclusive(const MCInst & MI,unsigned EncodedValue,const MCSubtargetInfo & STI) const629 AArch64MCCodeEmitter::fixLoadStoreExclusive(const MCInst &MI,
630                                             unsigned EncodedValue,
631                                             const MCSubtargetInfo &STI) const {
632   if (!hasRs) EncodedValue |= 0x001F0000;
633   if (!hasRt2) EncodedValue |= 0x00007C00;
634 
635   return EncodedValue;
636 }
637 
fixOneOperandFPComparison(const MCInst & MI,unsigned EncodedValue,const MCSubtargetInfo & STI) const638 unsigned AArch64MCCodeEmitter::fixOneOperandFPComparison(
639     const MCInst &MI, unsigned EncodedValue, const MCSubtargetInfo &STI) const {
640   // The Rm field of FCMP and friends is unused - it should be assembled
641   // as 0, but is ignored by the processor.
642   EncodedValue &= ~(0x1f << 16);
643   return EncodedValue;
644 }
645 
646 #include "AArch64GenMCCodeEmitter.inc"
647