xref: /freebsd/contrib/llvm-project/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MCCodeEmitter.cpp (revision 43a5ec4eb41567cc92586503212743d89686d78f)
1 //=- AArch64/AArch64MCCodeEmitter.cpp - Convert AArch64 code to machine code-=//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements the AArch64MCCodeEmitter class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "MCTargetDesc/AArch64AddressingModes.h"
14 #include "MCTargetDesc/AArch64FixupKinds.h"
15 #include "MCTargetDesc/AArch64MCExpr.h"
16 #include "Utils/AArch64BaseInfo.h"
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/ADT/Statistic.h"
19 #include "llvm/MC/MCCodeEmitter.h"
20 #include "llvm/MC/MCContext.h"
21 #include "llvm/MC/MCFixup.h"
22 #include "llvm/MC/MCInst.h"
23 #include "llvm/MC/MCInstrInfo.h"
24 #include "llvm/MC/MCRegisterInfo.h"
25 #include "llvm/MC/MCSubtargetInfo.h"
26 #include "llvm/Support/Casting.h"
27 #include "llvm/Support/Endian.h"
28 #include "llvm/Support/EndianStream.h"
29 #include "llvm/Support/ErrorHandling.h"
30 #include "llvm/Support/raw_ostream.h"
31 #include <cassert>
32 #include <cstdint>
33 
34 using namespace llvm;
35 
36 #define DEBUG_TYPE "mccodeemitter"
37 
38 STATISTIC(MCNumEmitted, "Number of MC instructions emitted.");
39 STATISTIC(MCNumFixups, "Number of MC fixups created.");
40 
41 namespace {
42 
43 class AArch64MCCodeEmitter : public MCCodeEmitter {
44   MCContext &Ctx;
45   const MCInstrInfo &MCII;
46 
47 public:
48   AArch64MCCodeEmitter(const MCInstrInfo &mcii, MCContext &ctx)
49       : Ctx(ctx), MCII(mcii) {}
50   AArch64MCCodeEmitter(const AArch64MCCodeEmitter &) = delete;
51   void operator=(const AArch64MCCodeEmitter &) = delete;
52   ~AArch64MCCodeEmitter() override = default;
53 
54   // getBinaryCodeForInstr - TableGen'erated function for getting the
55   // binary encoding for an instruction.
56   uint64_t getBinaryCodeForInstr(const MCInst &MI,
57                                  SmallVectorImpl<MCFixup> &Fixups,
58                                  const MCSubtargetInfo &STI) const;
59 
60   /// getMachineOpValue - Return binary encoding of operand. If the machine
61   /// operand requires relocation, record the relocation and return zero.
62   unsigned getMachineOpValue(const MCInst &MI, const MCOperand &MO,
63                              SmallVectorImpl<MCFixup> &Fixups,
64                              const MCSubtargetInfo &STI) const;
65 
66   /// getLdStUImm12OpValue - Return encoding info for 12-bit unsigned immediate
67   /// attached to a load, store or prfm instruction. If operand requires a
68   /// relocation, record it and return zero in that part of the encoding.
69   template <uint32_t FixupKind>
70   uint32_t getLdStUImm12OpValue(const MCInst &MI, unsigned OpIdx,
71                                 SmallVectorImpl<MCFixup> &Fixups,
72                                 const MCSubtargetInfo &STI) const;
73 
74   /// getAdrLabelOpValue - Return encoding info for 21-bit immediate ADR label
75   /// target.
76   uint32_t getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
77                               SmallVectorImpl<MCFixup> &Fixups,
78                               const MCSubtargetInfo &STI) const;
79 
80   /// getAddSubImmOpValue - Return encoding for the 12-bit immediate value and
81   /// the 2-bit shift field.
82   uint32_t getAddSubImmOpValue(const MCInst &MI, unsigned OpIdx,
83                                SmallVectorImpl<MCFixup> &Fixups,
84                                const MCSubtargetInfo &STI) const;
85 
86   /// getCondBranchTargetOpValue - Return the encoded value for a conditional
87   /// branch target.
88   uint32_t getCondBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
89                                       SmallVectorImpl<MCFixup> &Fixups,
90                                       const MCSubtargetInfo &STI) const;
91 
92   /// getLoadLiteralOpValue - Return the encoded value for a load-literal
93   /// pc-relative address.
94   uint32_t getLoadLiteralOpValue(const MCInst &MI, unsigned OpIdx,
95                                  SmallVectorImpl<MCFixup> &Fixups,
96                                  const MCSubtargetInfo &STI) const;
97 
98   /// getMemExtendOpValue - Return the encoded value for a reg-extend load/store
99   /// instruction: bit 0 is whether a shift is present, bit 1 is whether the
100   /// operation is a sign extend (as opposed to a zero extend).
101   uint32_t getMemExtendOpValue(const MCInst &MI, unsigned OpIdx,
102                                SmallVectorImpl<MCFixup> &Fixups,
103                                const MCSubtargetInfo &STI) const;
104 
105   /// getTestBranchTargetOpValue - Return the encoded value for a test-bit-and-
106   /// branch target.
107   uint32_t getTestBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
108                                       SmallVectorImpl<MCFixup> &Fixups,
109                                       const MCSubtargetInfo &STI) const;
110 
111   /// getBranchTargetOpValue - Return the encoded value for an unconditional
112   /// branch target.
113   uint32_t getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
114                                   SmallVectorImpl<MCFixup> &Fixups,
115                                   const MCSubtargetInfo &STI) const;
116 
117   /// getMoveWideImmOpValue - Return the encoded value for the immediate operand
118   /// of a MOVZ or MOVK instruction.
119   uint32_t getMoveWideImmOpValue(const MCInst &MI, unsigned OpIdx,
120                                  SmallVectorImpl<MCFixup> &Fixups,
121                                  const MCSubtargetInfo &STI) const;
122 
123   /// getVecShifterOpValue - Return the encoded value for the vector shifter.
124   uint32_t getVecShifterOpValue(const MCInst &MI, unsigned OpIdx,
125                                 SmallVectorImpl<MCFixup> &Fixups,
126                                 const MCSubtargetInfo &STI) const;
127 
128   /// getMoveVecShifterOpValue - Return the encoded value for the vector move
129   /// shifter (MSL).
130   uint32_t getMoveVecShifterOpValue(const MCInst &MI, unsigned OpIdx,
131                                     SmallVectorImpl<MCFixup> &Fixups,
132                                     const MCSubtargetInfo &STI) const;
133 
134   /// getFixedPointScaleOpValue - Return the encoded value for the
135   // FP-to-fixed-point scale factor.
136   uint32_t getFixedPointScaleOpValue(const MCInst &MI, unsigned OpIdx,
137                                      SmallVectorImpl<MCFixup> &Fixups,
138                                      const MCSubtargetInfo &STI) const;
139 
140   uint32_t getVecShiftR64OpValue(const MCInst &MI, unsigned OpIdx,
141                                  SmallVectorImpl<MCFixup> &Fixups,
142                                  const MCSubtargetInfo &STI) const;
143   uint32_t getVecShiftR32OpValue(const MCInst &MI, unsigned OpIdx,
144                                  SmallVectorImpl<MCFixup> &Fixups,
145                                  const MCSubtargetInfo &STI) const;
146   uint32_t getVecShiftR16OpValue(const MCInst &MI, unsigned OpIdx,
147                                  SmallVectorImpl<MCFixup> &Fixups,
148                                  const MCSubtargetInfo &STI) const;
149   uint32_t getVecShiftR8OpValue(const MCInst &MI, unsigned OpIdx,
150                                 SmallVectorImpl<MCFixup> &Fixups,
151                                 const MCSubtargetInfo &STI) const;
152   uint32_t getVecShiftL64OpValue(const MCInst &MI, unsigned OpIdx,
153                                  SmallVectorImpl<MCFixup> &Fixups,
154                                  const MCSubtargetInfo &STI) const;
155   uint32_t getVecShiftL32OpValue(const MCInst &MI, unsigned OpIdx,
156                                  SmallVectorImpl<MCFixup> &Fixups,
157                                  const MCSubtargetInfo &STI) const;
158   uint32_t getVecShiftL16OpValue(const MCInst &MI, unsigned OpIdx,
159                                  SmallVectorImpl<MCFixup> &Fixups,
160                                  const MCSubtargetInfo &STI) const;
161   uint32_t getVecShiftL8OpValue(const MCInst &MI, unsigned OpIdx,
162                                 SmallVectorImpl<MCFixup> &Fixups,
163                                 const MCSubtargetInfo &STI) const;
164 
165   uint32_t getImm8OptLsl(const MCInst &MI, unsigned OpIdx,
166                          SmallVectorImpl<MCFixup> &Fixups,
167                          const MCSubtargetInfo &STI) const;
168   uint32_t getSVEIncDecImm(const MCInst &MI, unsigned OpIdx,
169                            SmallVectorImpl<MCFixup> &Fixups,
170                            const MCSubtargetInfo &STI) const;
171 
172   unsigned fixMOVZ(const MCInst &MI, unsigned EncodedValue,
173                    const MCSubtargetInfo &STI) const;
174 
175   void encodeInstruction(const MCInst &MI, raw_ostream &OS,
176                          SmallVectorImpl<MCFixup> &Fixups,
177                          const MCSubtargetInfo &STI) const override;
178 
179   unsigned fixMulHigh(const MCInst &MI, unsigned EncodedValue,
180                       const MCSubtargetInfo &STI) const;
181 
182   template<int hasRs, int hasRt2> unsigned
183   fixLoadStoreExclusive(const MCInst &MI, unsigned EncodedValue,
184                         const MCSubtargetInfo &STI) const;
185 
186   unsigned fixOneOperandFPComparison(const MCInst &MI, unsigned EncodedValue,
187                                      const MCSubtargetInfo &STI) const;
188 
189   uint32_t EncodeMatrixTileListRegisterClass(const MCInst &MI, unsigned OpIdx,
190                                              SmallVectorImpl<MCFixup> &Fixups,
191                                              const MCSubtargetInfo &STI) const;
192   uint32_t encodeMatrixIndexGPR32(const MCInst &MI, unsigned OpIdx,
193                                   SmallVectorImpl<MCFixup> &Fixups,
194                                   const MCSubtargetInfo &STI) const;
195 
196 private:
197   FeatureBitset computeAvailableFeatures(const FeatureBitset &FB) const;
198   void
199   verifyInstructionPredicates(const MCInst &MI,
200                               const FeatureBitset &AvailableFeatures) const;
201 };
202 
203 } // end anonymous namespace
204 
205 /// getMachineOpValue - Return binary encoding of operand. If the machine
206 /// operand requires relocation, record the relocation and return zero.
207 unsigned
208 AArch64MCCodeEmitter::getMachineOpValue(const MCInst &MI, const MCOperand &MO,
209                                         SmallVectorImpl<MCFixup> &Fixups,
210                                         const MCSubtargetInfo &STI) const {
211   if (MO.isReg())
212     return Ctx.getRegisterInfo()->getEncodingValue(MO.getReg());
213 
214   assert(MO.isImm() && "did not expect relocated expression");
215   return static_cast<unsigned>(MO.getImm());
216 }
217 
218 template<unsigned FixupKind> uint32_t
219 AArch64MCCodeEmitter::getLdStUImm12OpValue(const MCInst &MI, unsigned OpIdx,
220                                            SmallVectorImpl<MCFixup> &Fixups,
221                                            const MCSubtargetInfo &STI) const {
222   const MCOperand &MO = MI.getOperand(OpIdx);
223   uint32_t ImmVal = 0;
224 
225   if (MO.isImm())
226     ImmVal = static_cast<uint32_t>(MO.getImm());
227   else {
228     assert(MO.isExpr() && "unable to encode load/store imm operand");
229     MCFixupKind Kind = MCFixupKind(FixupKind);
230     Fixups.push_back(MCFixup::create(0, MO.getExpr(), Kind, MI.getLoc()));
231     ++MCNumFixups;
232   }
233 
234   return ImmVal;
235 }
236 
237 /// getAdrLabelOpValue - Return encoding info for 21-bit immediate ADR label
238 /// target.
239 uint32_t
240 AArch64MCCodeEmitter::getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
241                                          SmallVectorImpl<MCFixup> &Fixups,
242                                          const MCSubtargetInfo &STI) const {
243   const MCOperand &MO = MI.getOperand(OpIdx);
244 
245   // If the destination is an immediate, we have nothing to do.
246   if (MO.isImm())
247     return MO.getImm();
248   assert(MO.isExpr() && "Unexpected target type!");
249   const MCExpr *Expr = MO.getExpr();
250 
251   MCFixupKind Kind = MI.getOpcode() == AArch64::ADR
252                          ? MCFixupKind(AArch64::fixup_aarch64_pcrel_adr_imm21)
253                          : MCFixupKind(AArch64::fixup_aarch64_pcrel_adrp_imm21);
254   Fixups.push_back(MCFixup::create(0, Expr, Kind, MI.getLoc()));
255 
256   MCNumFixups += 1;
257 
258   // All of the information is in the fixup.
259   return 0;
260 }
261 
262 /// getAddSubImmOpValue - Return encoding for the 12-bit immediate value and
263 /// the 2-bit shift field.  The shift field is stored in bits 13-14 of the
264 /// return value.
265 uint32_t
266 AArch64MCCodeEmitter::getAddSubImmOpValue(const MCInst &MI, unsigned OpIdx,
267                                           SmallVectorImpl<MCFixup> &Fixups,
268                                           const MCSubtargetInfo &STI) const {
269   // Suboperands are [imm, shifter].
270   const MCOperand &MO = MI.getOperand(OpIdx);
271   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
272   assert(AArch64_AM::getShiftType(MO1.getImm()) == AArch64_AM::LSL &&
273          "unexpected shift type for add/sub immediate");
274   unsigned ShiftVal = AArch64_AM::getShiftValue(MO1.getImm());
275   assert((ShiftVal == 0 || ShiftVal == 12) &&
276          "unexpected shift value for add/sub immediate");
277   if (MO.isImm())
278     return MO.getImm() | (ShiftVal == 0 ? 0 : (1 << ShiftVal));
279   assert(MO.isExpr() && "Unable to encode MCOperand!");
280   const MCExpr *Expr = MO.getExpr();
281 
282   // Encode the 12 bits of the fixup.
283   MCFixupKind Kind = MCFixupKind(AArch64::fixup_aarch64_add_imm12);
284   Fixups.push_back(MCFixup::create(0, Expr, Kind, MI.getLoc()));
285 
286   ++MCNumFixups;
287 
288   // Set the shift bit of the add instruction for relocation types
289   // R_AARCH64_TLSLE_ADD_TPREL_HI12 and R_AARCH64_TLSLD_ADD_DTPREL_HI12.
290   if (const AArch64MCExpr *A64E = dyn_cast<AArch64MCExpr>(Expr)) {
291     AArch64MCExpr::VariantKind RefKind = A64E->getKind();
292     if (RefKind == AArch64MCExpr::VK_TPREL_HI12 ||
293         RefKind == AArch64MCExpr::VK_DTPREL_HI12 ||
294         RefKind == AArch64MCExpr::VK_SECREL_HI12)
295       ShiftVal = 12;
296   }
297   return ShiftVal == 0 ? 0 : (1 << ShiftVal);
298 }
299 
300 /// getCondBranchTargetOpValue - Return the encoded value for a conditional
301 /// branch target.
302 uint32_t AArch64MCCodeEmitter::getCondBranchTargetOpValue(
303     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
304     const MCSubtargetInfo &STI) const {
305   const MCOperand &MO = MI.getOperand(OpIdx);
306 
307   // If the destination is an immediate, we have nothing to do.
308   if (MO.isImm())
309     return MO.getImm();
310   assert(MO.isExpr() && "Unexpected target type!");
311 
312   MCFixupKind Kind = MCFixupKind(AArch64::fixup_aarch64_pcrel_branch19);
313   Fixups.push_back(MCFixup::create(0, MO.getExpr(), Kind, MI.getLoc()));
314 
315   ++MCNumFixups;
316 
317   // All of the information is in the fixup.
318   return 0;
319 }
320 
321 /// getLoadLiteralOpValue - Return the encoded value for a load-literal
322 /// pc-relative address.
323 uint32_t
324 AArch64MCCodeEmitter::getLoadLiteralOpValue(const MCInst &MI, unsigned OpIdx,
325                                             SmallVectorImpl<MCFixup> &Fixups,
326                                             const MCSubtargetInfo &STI) const {
327   const MCOperand &MO = MI.getOperand(OpIdx);
328 
329   // If the destination is an immediate, we have nothing to do.
330   if (MO.isImm())
331     return MO.getImm();
332   assert(MO.isExpr() && "Unexpected target type!");
333 
334   MCFixupKind Kind = MCFixupKind(AArch64::fixup_aarch64_ldr_pcrel_imm19);
335   Fixups.push_back(MCFixup::create(0, MO.getExpr(), Kind, MI.getLoc()));
336 
337   ++MCNumFixups;
338 
339   // All of the information is in the fixup.
340   return 0;
341 }
342 
343 uint32_t
344 AArch64MCCodeEmitter::getMemExtendOpValue(const MCInst &MI, unsigned OpIdx,
345                                           SmallVectorImpl<MCFixup> &Fixups,
346                                           const MCSubtargetInfo &STI) const {
347   unsigned SignExtend = MI.getOperand(OpIdx).getImm();
348   unsigned DoShift = MI.getOperand(OpIdx + 1).getImm();
349   return (SignExtend << 1) | DoShift;
350 }
351 
352 uint32_t
353 AArch64MCCodeEmitter::getMoveWideImmOpValue(const MCInst &MI, unsigned OpIdx,
354                                             SmallVectorImpl<MCFixup> &Fixups,
355                                             const MCSubtargetInfo &STI) const {
356   const MCOperand &MO = MI.getOperand(OpIdx);
357 
358   if (MO.isImm())
359     return MO.getImm();
360   assert(MO.isExpr() && "Unexpected movz/movk immediate");
361 
362   Fixups.push_back(MCFixup::create(
363       0, MO.getExpr(), MCFixupKind(AArch64::fixup_aarch64_movw), MI.getLoc()));
364 
365   ++MCNumFixups;
366 
367   return 0;
368 }
369 
370 /// getTestBranchTargetOpValue - Return the encoded value for a test-bit-and-
371 /// branch target.
372 uint32_t AArch64MCCodeEmitter::getTestBranchTargetOpValue(
373     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
374     const MCSubtargetInfo &STI) const {
375   const MCOperand &MO = MI.getOperand(OpIdx);
376 
377   // If the destination is an immediate, we have nothing to do.
378   if (MO.isImm())
379     return MO.getImm();
380   assert(MO.isExpr() && "Unexpected ADR target type!");
381 
382   MCFixupKind Kind = MCFixupKind(AArch64::fixup_aarch64_pcrel_branch14);
383   Fixups.push_back(MCFixup::create(0, MO.getExpr(), Kind, MI.getLoc()));
384 
385   ++MCNumFixups;
386 
387   // All of the information is in the fixup.
388   return 0;
389 }
390 
391 /// getBranchTargetOpValue - Return the encoded value for an unconditional
392 /// branch target.
393 uint32_t
394 AArch64MCCodeEmitter::getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
395                                              SmallVectorImpl<MCFixup> &Fixups,
396                                              const MCSubtargetInfo &STI) const {
397   const MCOperand &MO = MI.getOperand(OpIdx);
398 
399   // If the destination is an immediate, we have nothing to do.
400   if (MO.isImm())
401     return MO.getImm();
402   assert(MO.isExpr() && "Unexpected ADR target type!");
403 
404   MCFixupKind Kind = MI.getOpcode() == AArch64::BL
405                          ? MCFixupKind(AArch64::fixup_aarch64_pcrel_call26)
406                          : MCFixupKind(AArch64::fixup_aarch64_pcrel_branch26);
407   Fixups.push_back(MCFixup::create(0, MO.getExpr(), Kind, MI.getLoc()));
408 
409   ++MCNumFixups;
410 
411   // All of the information is in the fixup.
412   return 0;
413 }
414 
415 /// getVecShifterOpValue - Return the encoded value for the vector shifter:
416 ///
417 ///   00 -> 0
418 ///   01 -> 8
419 ///   10 -> 16
420 ///   11 -> 24
421 uint32_t
422 AArch64MCCodeEmitter::getVecShifterOpValue(const MCInst &MI, unsigned OpIdx,
423                                            SmallVectorImpl<MCFixup> &Fixups,
424                                            const MCSubtargetInfo &STI) const {
425   const MCOperand &MO = MI.getOperand(OpIdx);
426   assert(MO.isImm() && "Expected an immediate value for the shift amount!");
427 
428   switch (MO.getImm()) {
429   default:
430     break;
431   case 0:
432     return 0;
433   case 8:
434     return 1;
435   case 16:
436     return 2;
437   case 24:
438     return 3;
439   }
440 
441   llvm_unreachable("Invalid value for vector shift amount!");
442 }
443 
444 /// getFixedPointScaleOpValue - Return the encoded value for the
445 // FP-to-fixed-point scale factor.
446 uint32_t AArch64MCCodeEmitter::getFixedPointScaleOpValue(
447     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
448     const MCSubtargetInfo &STI) const {
449   const MCOperand &MO = MI.getOperand(OpIdx);
450   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
451   return 64 - MO.getImm();
452 }
453 
454 uint32_t
455 AArch64MCCodeEmitter::getVecShiftR64OpValue(const MCInst &MI, unsigned OpIdx,
456                                             SmallVectorImpl<MCFixup> &Fixups,
457                                             const MCSubtargetInfo &STI) const {
458   const MCOperand &MO = MI.getOperand(OpIdx);
459   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
460   return 64 - MO.getImm();
461 }
462 
463 uint32_t
464 AArch64MCCodeEmitter::getVecShiftR32OpValue(const MCInst &MI, unsigned OpIdx,
465                                             SmallVectorImpl<MCFixup> &Fixups,
466                                             const MCSubtargetInfo &STI) const {
467   const MCOperand &MO = MI.getOperand(OpIdx);
468   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
469   return 32 - MO.getImm();
470 }
471 
472 uint32_t
473 AArch64MCCodeEmitter::getVecShiftR16OpValue(const MCInst &MI, unsigned OpIdx,
474                                             SmallVectorImpl<MCFixup> &Fixups,
475                                             const MCSubtargetInfo &STI) const {
476   const MCOperand &MO = MI.getOperand(OpIdx);
477   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
478   return 16 - MO.getImm();
479 }
480 
481 uint32_t
482 AArch64MCCodeEmitter::getVecShiftR8OpValue(const MCInst &MI, unsigned OpIdx,
483                                            SmallVectorImpl<MCFixup> &Fixups,
484                                            const MCSubtargetInfo &STI) const {
485   const MCOperand &MO = MI.getOperand(OpIdx);
486   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
487   return 8 - MO.getImm();
488 }
489 
490 uint32_t
491 AArch64MCCodeEmitter::getVecShiftL64OpValue(const MCInst &MI, unsigned OpIdx,
492                                             SmallVectorImpl<MCFixup> &Fixups,
493                                             const MCSubtargetInfo &STI) const {
494   const MCOperand &MO = MI.getOperand(OpIdx);
495   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
496   return MO.getImm() - 64;
497 }
498 
499 uint32_t
500 AArch64MCCodeEmitter::getVecShiftL32OpValue(const MCInst &MI, unsigned OpIdx,
501                                             SmallVectorImpl<MCFixup> &Fixups,
502                                             const MCSubtargetInfo &STI) const {
503   const MCOperand &MO = MI.getOperand(OpIdx);
504   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
505   return MO.getImm() - 32;
506 }
507 
508 uint32_t
509 AArch64MCCodeEmitter::getVecShiftL16OpValue(const MCInst &MI, unsigned OpIdx,
510                                             SmallVectorImpl<MCFixup> &Fixups,
511                                             const MCSubtargetInfo &STI) const {
512   const MCOperand &MO = MI.getOperand(OpIdx);
513   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
514   return MO.getImm() - 16;
515 }
516 
517 uint32_t
518 AArch64MCCodeEmitter::getVecShiftL8OpValue(const MCInst &MI, unsigned OpIdx,
519                                            SmallVectorImpl<MCFixup> &Fixups,
520                                            const MCSubtargetInfo &STI) const {
521   const MCOperand &MO = MI.getOperand(OpIdx);
522   assert(MO.isImm() && "Expected an immediate value for the scale amount!");
523   return MO.getImm() - 8;
524 }
525 
526 uint32_t AArch64MCCodeEmitter::EncodeMatrixTileListRegisterClass(
527     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
528     const MCSubtargetInfo &STI) const {
529   unsigned RegMask = MI.getOperand(OpIdx).getImm();
530   assert(RegMask <= 0xFF && "Invalid register mask!");
531   return RegMask;
532 }
533 
534 uint32_t
535 AArch64MCCodeEmitter::encodeMatrixIndexGPR32(const MCInst &MI, unsigned OpIdx,
536                                              SmallVectorImpl<MCFixup> &Fixups,
537                                              const MCSubtargetInfo &STI) const {
538   auto RegOpnd = MI.getOperand(OpIdx).getReg();
539   assert(RegOpnd >= AArch64::W12 && RegOpnd <= AArch64::W15 &&
540          "Expected register in the range w12-w15!");
541   return RegOpnd - AArch64::W12;
542 }
543 
544 uint32_t
545 AArch64MCCodeEmitter::getImm8OptLsl(const MCInst &MI, unsigned OpIdx,
546                                     SmallVectorImpl<MCFixup> &Fixups,
547                                     const MCSubtargetInfo &STI) const {
548   // Test shift
549   auto ShiftOpnd = MI.getOperand(OpIdx + 1).getImm();
550   assert(AArch64_AM::getShiftType(ShiftOpnd) == AArch64_AM::LSL &&
551          "Unexpected shift type for imm8_opt_lsl immediate.");
552 
553   unsigned ShiftVal = AArch64_AM::getShiftValue(ShiftOpnd);
554   assert((ShiftVal == 0 || ShiftVal == 8) &&
555          "Unexpected shift value for imm8_opt_lsl immediate.");
556 
557   // Test immediate
558   auto Immediate = MI.getOperand(OpIdx).getImm();
559   return (Immediate & 0xff) | (ShiftVal == 0 ? 0 : (1 << ShiftVal));
560 }
561 
562 uint32_t
563 AArch64MCCodeEmitter::getSVEIncDecImm(const MCInst &MI, unsigned OpIdx,
564                                            SmallVectorImpl<MCFixup> &Fixups,
565                                            const MCSubtargetInfo &STI) const {
566   const MCOperand &MO = MI.getOperand(OpIdx);
567   assert(MO.isImm() && "Expected an immediate value!");
568   // Normalize 1-16 range to 0-15.
569   return MO.getImm() - 1;
570 }
571 
572 /// getMoveVecShifterOpValue - Return the encoded value for the vector move
573 /// shifter (MSL).
574 uint32_t AArch64MCCodeEmitter::getMoveVecShifterOpValue(
575     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
576     const MCSubtargetInfo &STI) const {
577   const MCOperand &MO = MI.getOperand(OpIdx);
578   assert(MO.isImm() &&
579          "Expected an immediate value for the move shift amount!");
580   unsigned ShiftVal = AArch64_AM::getShiftValue(MO.getImm());
581   assert((ShiftVal == 8 || ShiftVal == 16) && "Invalid shift amount!");
582   return ShiftVal == 8 ? 0 : 1;
583 }
584 
585 unsigned AArch64MCCodeEmitter::fixMOVZ(const MCInst &MI, unsigned EncodedValue,
586                                        const MCSubtargetInfo &STI) const {
587   // If one of the signed fixup kinds is applied to a MOVZ instruction, the
588   // eventual result could be either a MOVZ or a MOVN. It's the MCCodeEmitter's
589   // job to ensure that any bits possibly affected by this are 0. This means we
590   // must zero out bit 30 (essentially emitting a MOVN).
591   MCOperand UImm16MO = MI.getOperand(1);
592 
593   // Nothing to do if there's no fixup.
594   if (UImm16MO.isImm())
595     return EncodedValue;
596 
597   const MCExpr *E = UImm16MO.getExpr();
598   if (const AArch64MCExpr *A64E = dyn_cast<AArch64MCExpr>(E)) {
599     switch (A64E->getKind()) {
600     case AArch64MCExpr::VK_DTPREL_G2:
601     case AArch64MCExpr::VK_DTPREL_G1:
602     case AArch64MCExpr::VK_DTPREL_G0:
603     case AArch64MCExpr::VK_GOTTPREL_G1:
604     case AArch64MCExpr::VK_TPREL_G2:
605     case AArch64MCExpr::VK_TPREL_G1:
606     case AArch64MCExpr::VK_TPREL_G0:
607       return EncodedValue & ~(1u << 30);
608     default:
609       // Nothing to do for an unsigned fixup.
610       return EncodedValue;
611     }
612   }
613 
614   return EncodedValue;
615 }
616 
617 void AArch64MCCodeEmitter::encodeInstruction(const MCInst &MI, raw_ostream &OS,
618                                              SmallVectorImpl<MCFixup> &Fixups,
619                                              const MCSubtargetInfo &STI) const {
620   verifyInstructionPredicates(MI,
621                               computeAvailableFeatures(STI.getFeatureBits()));
622 
623   if (MI.getOpcode() == AArch64::TLSDESCCALL) {
624     // This is a directive which applies an R_AARCH64_TLSDESC_CALL to the
625     // following (BLR) instruction. It doesn't emit any code itself so it
626     // doesn't go through the normal TableGenerated channels.
627     auto Reloc = STI.getTargetTriple().getEnvironment() == Triple::GNUILP32
628                      ? ELF::R_AARCH64_P32_TLSDESC_CALL
629                      : ELF::R_AARCH64_TLSDESC_CALL;
630     Fixups.push_back(
631         MCFixup::create(0, MI.getOperand(0).getExpr(),
632                         MCFixupKind(FirstLiteralRelocationKind + Reloc)));
633     return;
634   }
635 
636   if (MI.getOpcode() == AArch64::CompilerBarrier ||
637       MI.getOpcode() == AArch64::SPACE) {
638     // CompilerBarrier just prevents the compiler from reordering accesses, and
639     // SPACE just increases basic block size, in both cases no actual code.
640     return;
641   }
642 
643   uint64_t Binary = getBinaryCodeForInstr(MI, Fixups, STI);
644   support::endian::write<uint32_t>(OS, Binary, support::little);
645   ++MCNumEmitted; // Keep track of the # of mi's emitted.
646 }
647 
648 unsigned
649 AArch64MCCodeEmitter::fixMulHigh(const MCInst &MI,
650                                  unsigned EncodedValue,
651                                  const MCSubtargetInfo &STI) const {
652   // The Ra field of SMULH and UMULH is unused: it should be assembled as 31
653   // (i.e. all bits 1) but is ignored by the processor.
654   EncodedValue |= 0x1f << 10;
655   return EncodedValue;
656 }
657 
658 template<int hasRs, int hasRt2> unsigned
659 AArch64MCCodeEmitter::fixLoadStoreExclusive(const MCInst &MI,
660                                             unsigned EncodedValue,
661                                             const MCSubtargetInfo &STI) const {
662   if (!hasRs) EncodedValue |= 0x001F0000;
663   if (!hasRt2) EncodedValue |= 0x00007C00;
664 
665   return EncodedValue;
666 }
667 
668 unsigned AArch64MCCodeEmitter::fixOneOperandFPComparison(
669     const MCInst &MI, unsigned EncodedValue, const MCSubtargetInfo &STI) const {
670   // The Rm field of FCMP and friends is unused - it should be assembled
671   // as 0, but is ignored by the processor.
672   EncodedValue &= ~(0x1f << 16);
673   return EncodedValue;
674 }
675 
676 #define ENABLE_INSTR_PREDICATE_VERIFIER
677 #include "AArch64GenMCCodeEmitter.inc"
678 
679 MCCodeEmitter *llvm::createAArch64MCCodeEmitter(const MCInstrInfo &MCII,
680                                                 const MCRegisterInfo &MRI,
681                                                 MCContext &Ctx) {
682   return new AArch64MCCodeEmitter(MCII, Ctx);
683 }
684