xref: /freebsd/contrib/llvm-project/llvm/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp (revision 0ad011ececb978e22a9bff2acf76633b094f1ff6)
1 //===-- ARM/ARMMCCodeEmitter.cpp - Convert ARM 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 ARMMCCodeEmitter class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "MCTargetDesc/ARMAddressingModes.h"
14 #include "MCTargetDesc/ARMBaseInfo.h"
15 #include "MCTargetDesc/ARMFixupKinds.h"
16 #include "MCTargetDesc/ARMMCExpr.h"
17 #include "llvm/ADT/APFloat.h"
18 #include "llvm/ADT/APInt.h"
19 #include "llvm/ADT/SmallVector.h"
20 #include "llvm/ADT/Statistic.h"
21 #include "llvm/MC/MCCodeEmitter.h"
22 #include "llvm/MC/MCContext.h"
23 #include "llvm/MC/MCExpr.h"
24 #include "llvm/MC/MCFixup.h"
25 #include "llvm/MC/MCInst.h"
26 #include "llvm/MC/MCInstrDesc.h"
27 #include "llvm/MC/MCInstrInfo.h"
28 #include "llvm/MC/MCRegisterInfo.h"
29 #include "llvm/MC/MCSubtargetInfo.h"
30 #include "llvm/Support/Casting.h"
31 #include "llvm/Support/Compiler.h"
32 #include "llvm/Support/ErrorHandling.h"
33 #include "llvm/Support/MathExtras.h"
34 #include "llvm/Support/raw_ostream.h"
35 #include "llvm/TargetParser/Triple.h"
36 #include <algorithm>
37 #include <cassert>
38 #include <cstdint>
39 #include <cstdlib>
40 
41 using namespace llvm;
42 
43 #define DEBUG_TYPE "mccodeemitter"
44 
45 STATISTIC(MCNumEmitted, "Number of MC instructions emitted.");
46 STATISTIC(MCNumCPRelocations, "Number of constant pool relocations created.");
47 
48 namespace {
49 
50 class ARMMCCodeEmitter : public MCCodeEmitter {
51   const MCInstrInfo &MCII;
52   MCContext &CTX;
53   bool IsLittleEndian;
54 
55 public:
56   ARMMCCodeEmitter(const MCInstrInfo &mcii, MCContext &ctx, bool IsLittle)
57     : MCII(mcii), CTX(ctx), IsLittleEndian(IsLittle) {
58   }
59   ARMMCCodeEmitter(const ARMMCCodeEmitter &) = delete;
60   ARMMCCodeEmitter &operator=(const ARMMCCodeEmitter &) = delete;
61   ~ARMMCCodeEmitter() override = default;
62 
63   bool isThumb(const MCSubtargetInfo &STI) const {
64     return STI.hasFeature(ARM::ModeThumb);
65   }
66 
67   bool isThumb2(const MCSubtargetInfo &STI) const {
68     return isThumb(STI) && STI.hasFeature(ARM::FeatureThumb2);
69   }
70 
71   bool isTargetMachO(const MCSubtargetInfo &STI) const {
72     const Triple &TT = STI.getTargetTriple();
73     return TT.isOSBinFormatMachO();
74   }
75 
76   unsigned getMachineSoImmOpValue(unsigned SoImm) const;
77 
78   // getBinaryCodeForInstr - TableGen'erated function for getting the
79   // binary encoding for an instruction.
80   uint64_t getBinaryCodeForInstr(const MCInst &MI,
81                                  SmallVectorImpl<MCFixup> &Fixups,
82                                  const MCSubtargetInfo &STI) const;
83 
84   /// getMachineOpValue - Return binary encoding of operand. If the machine
85   /// operand requires relocation, record the relocation and return zero.
86   unsigned getMachineOpValue(const MCInst &MI,const MCOperand &MO,
87                              SmallVectorImpl<MCFixup> &Fixups,
88                              const MCSubtargetInfo &STI) const;
89 
90   /// getHiLoImmOpValue - Return the encoding for either the hi / low 16-bit, or
91   /// high/middle-high/middle-low/low 8 bits of the specified operand. This is
92   /// used for operands with :lower16:, :upper16: :lower0_7:, :lower8_15:,
93   /// :higher0_7:, and :higher8_15: prefixes.
94   uint32_t getHiLoImmOpValue(const MCInst &MI, unsigned OpIdx,
95                              SmallVectorImpl<MCFixup> &Fixups,
96                              const MCSubtargetInfo &STI) const;
97 
98   bool EncodeAddrModeOpValues(const MCInst &MI, unsigned OpIdx,
99                               unsigned &Reg, unsigned &Imm,
100                               SmallVectorImpl<MCFixup> &Fixups,
101                               const MCSubtargetInfo &STI) const;
102 
103   /// getThumbBLTargetOpValue - Return encoding info for Thumb immediate
104   /// BL branch target.
105   uint32_t getThumbBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
106                                    SmallVectorImpl<MCFixup> &Fixups,
107                                    const MCSubtargetInfo &STI) const;
108 
109   /// getThumbBLXTargetOpValue - Return encoding info for Thumb immediate
110   /// BLX branch target.
111   uint32_t getThumbBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
112                                     SmallVectorImpl<MCFixup> &Fixups,
113                                     const MCSubtargetInfo &STI) const;
114 
115   /// getThumbBRTargetOpValue - Return encoding info for Thumb branch target.
116   uint32_t getThumbBRTargetOpValue(const MCInst &MI, unsigned OpIdx,
117                                    SmallVectorImpl<MCFixup> &Fixups,
118                                    const MCSubtargetInfo &STI) const;
119 
120   /// getThumbBCCTargetOpValue - Return encoding info for Thumb branch target.
121   uint32_t getThumbBCCTargetOpValue(const MCInst &MI, unsigned OpIdx,
122                                     SmallVectorImpl<MCFixup> &Fixups,
123                                     const MCSubtargetInfo &STI) const;
124 
125   /// getThumbCBTargetOpValue - Return encoding info for Thumb branch target.
126   uint32_t getThumbCBTargetOpValue(const MCInst &MI, unsigned OpIdx,
127                                    SmallVectorImpl<MCFixup> &Fixups,
128                                    const MCSubtargetInfo &STI) const;
129 
130   /// getBranchTargetOpValue - Return encoding info for 24-bit immediate
131   /// branch target.
132   uint32_t getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
133                                   SmallVectorImpl<MCFixup> &Fixups,
134                                   const MCSubtargetInfo &STI) const;
135 
136   /// getThumbBranchTargetOpValue - Return encoding info for 24-bit
137   /// immediate Thumb2 direct branch target.
138   uint32_t getThumbBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
139                                        SmallVectorImpl<MCFixup> &Fixups,
140                                        const MCSubtargetInfo &STI) const;
141 
142   /// getARMBranchTargetOpValue - Return encoding info for 24-bit immediate
143   /// branch target.
144   uint32_t getARMBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
145                                      SmallVectorImpl<MCFixup> &Fixups,
146                                      const MCSubtargetInfo &STI) const;
147   uint32_t getARMBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
148                                  SmallVectorImpl<MCFixup> &Fixups,
149                                  const MCSubtargetInfo &STI) const;
150   uint32_t getARMBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
151                                   SmallVectorImpl<MCFixup> &Fixups,
152                                   const MCSubtargetInfo &STI) const;
153 
154   /// getAdrLabelOpValue - Return encoding info for 12-bit immediate
155   /// ADR label target.
156   uint32_t getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
157                               SmallVectorImpl<MCFixup> &Fixups,
158                               const MCSubtargetInfo &STI) const;
159   uint32_t getThumbAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
160                               SmallVectorImpl<MCFixup> &Fixups,
161                               const MCSubtargetInfo &STI) const;
162   uint32_t getT2AdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
163                               SmallVectorImpl<MCFixup> &Fixups,
164                               const MCSubtargetInfo &STI) const;
165 
166   uint32_t getITMaskOpValue(const MCInst &MI, unsigned OpIdx,
167                             SmallVectorImpl<MCFixup> &Fixups,
168                             const MCSubtargetInfo &STI) const;
169 
170   /// getMVEShiftImmOpValue - Return encoding info for the 'sz:imm5'
171   /// operand.
172   uint32_t getMVEShiftImmOpValue(const MCInst &MI, unsigned OpIdx,
173                                  SmallVectorImpl<MCFixup> &Fixups,
174                                  const MCSubtargetInfo &STI) const;
175 
176   /// getAddrModeImm12OpValue - Return encoding info for 'reg +/- imm12'
177   /// operand.
178   uint32_t getAddrModeImm12OpValue(const MCInst &MI, unsigned OpIdx,
179                                    SmallVectorImpl<MCFixup> &Fixups,
180                                    const MCSubtargetInfo &STI) const;
181 
182   /// getThumbAddrModeRegRegOpValue - Return encoding for 'reg + reg' operand.
183   uint32_t getThumbAddrModeRegRegOpValue(const MCInst &MI, unsigned OpIdx,
184                                          SmallVectorImpl<MCFixup> &Fixups,
185                                          const MCSubtargetInfo &STI) const;
186 
187   /// getT2AddrModeImm8s4OpValue - Return encoding info for 'reg +/- imm8<<2'
188   /// operand.
189   uint32_t getT2AddrModeImm8s4OpValue(const MCInst &MI, unsigned OpIdx,
190                                    SmallVectorImpl<MCFixup> &Fixups,
191                                    const MCSubtargetInfo &STI) const;
192 
193   /// getT2AddrModeImm7s4OpValue - Return encoding info for 'reg +/- imm7<<2'
194   /// operand.
195   uint32_t getT2AddrModeImm7s4OpValue(const MCInst &MI, unsigned OpIdx,
196                                       SmallVectorImpl<MCFixup> &Fixups,
197                                       const MCSubtargetInfo &STI) const;
198 
199   /// getT2AddrModeImm0_1020s4OpValue - Return encoding info for 'reg + imm8<<2'
200   /// operand.
201   uint32_t getT2AddrModeImm0_1020s4OpValue(const MCInst &MI, unsigned OpIdx,
202                                    SmallVectorImpl<MCFixup> &Fixups,
203                                    const MCSubtargetInfo &STI) const;
204 
205   /// getT2ScaledImmOpValue - Return encoding info for '+/- immX<<Y'
206   /// operand.
207   template<unsigned Bits, unsigned Shift>
208   uint32_t getT2ScaledImmOpValue(const MCInst &MI, unsigned OpIdx,
209                                  SmallVectorImpl<MCFixup> &Fixups,
210                                  const MCSubtargetInfo &STI) const;
211 
212   /// getMveAddrModeRQOpValue - Return encoding info for 'reg, vreg'
213   /// operand.
214   uint32_t getMveAddrModeRQOpValue(const MCInst &MI, unsigned OpIdx,
215                                    SmallVectorImpl<MCFixup> &Fixups,
216                                    const MCSubtargetInfo &STI) const;
217 
218   /// getMveAddrModeQOpValue - Return encoding info for 'reg +/- imm7<<{shift}'
219   /// operand.
220   template<int shift>
221   uint32_t getMveAddrModeQOpValue(const MCInst &MI, unsigned OpIdx,
222                                   SmallVectorImpl<MCFixup> &Fixups,
223                                   const MCSubtargetInfo &STI) const;
224 
225   /// getLdStSORegOpValue - Return encoding info for 'reg +/- reg shop imm'
226   /// operand as needed by load/store instructions.
227   uint32_t getLdStSORegOpValue(const MCInst &MI, unsigned OpIdx,
228                                SmallVectorImpl<MCFixup> &Fixups,
229                                const MCSubtargetInfo &STI) const;
230 
231   /// getLdStmModeOpValue - Return encoding for load/store multiple mode.
232   uint32_t getLdStmModeOpValue(const MCInst &MI, unsigned OpIdx,
233                                SmallVectorImpl<MCFixup> &Fixups,
234                                const MCSubtargetInfo &STI) const {
235     ARM_AM::AMSubMode Mode = (ARM_AM::AMSubMode)MI.getOperand(OpIdx).getImm();
236     switch (Mode) {
237     default: llvm_unreachable("Unknown addressing sub-mode!");
238     case ARM_AM::da: return 0;
239     case ARM_AM::ia: return 1;
240     case ARM_AM::db: return 2;
241     case ARM_AM::ib: return 3;
242     }
243   }
244 
245   /// getShiftOp - Return the shift opcode (bit[6:5]) of the immediate value.
246   ///
247   unsigned getShiftOp(ARM_AM::ShiftOpc ShOpc) const {
248     switch (ShOpc) {
249     case ARM_AM::no_shift:
250     case ARM_AM::lsl: return 0;
251     case ARM_AM::lsr: return 1;
252     case ARM_AM::asr: return 2;
253     case ARM_AM::ror:
254     case ARM_AM::rrx: return 3;
255     default:
256       llvm_unreachable("Invalid ShiftOpc!");
257     }
258   }
259 
260   /// getAddrMode2OffsetOpValue - Return encoding for am2offset operands.
261   uint32_t getAddrMode2OffsetOpValue(const MCInst &MI, unsigned OpIdx,
262                                      SmallVectorImpl<MCFixup> &Fixups,
263                                      const MCSubtargetInfo &STI) const;
264 
265   /// getPostIdxRegOpValue - Return encoding for postidx_reg operands.
266   uint32_t getPostIdxRegOpValue(const MCInst &MI, unsigned OpIdx,
267                                 SmallVectorImpl<MCFixup> &Fixups,
268                                 const MCSubtargetInfo &STI) const;
269 
270   /// getAddrMode3OffsetOpValue - Return encoding for am3offset operands.
271   uint32_t getAddrMode3OffsetOpValue(const MCInst &MI, unsigned OpIdx,
272                                      SmallVectorImpl<MCFixup> &Fixups,
273                                      const MCSubtargetInfo &STI) const;
274 
275   /// getAddrMode3OpValue - Return encoding for addrmode3 operands.
276   uint32_t getAddrMode3OpValue(const MCInst &MI, unsigned OpIdx,
277                                SmallVectorImpl<MCFixup> &Fixups,
278                                const MCSubtargetInfo &STI) const;
279 
280   /// getAddrModeThumbSPOpValue - Return encoding info for 'reg +/- imm12'
281   /// operand.
282   uint32_t getAddrModeThumbSPOpValue(const MCInst &MI, unsigned OpIdx,
283                                      SmallVectorImpl<MCFixup> &Fixups,
284                                      const MCSubtargetInfo &STI) const;
285 
286   /// getAddrModeISOpValue - Encode the t_addrmode_is# operands.
287   uint32_t getAddrModeISOpValue(const MCInst &MI, unsigned OpIdx,
288                                 SmallVectorImpl<MCFixup> &Fixups,
289                                 const MCSubtargetInfo &STI) const;
290 
291   /// getAddrModePCOpValue - Return encoding for t_addrmode_pc operands.
292   uint32_t getAddrModePCOpValue(const MCInst &MI, unsigned OpIdx,
293                                 SmallVectorImpl<MCFixup> &Fixups,
294                                 const MCSubtargetInfo &STI) const;
295 
296   /// getAddrMode5OpValue - Return encoding info for 'reg +/- (imm8 << 2)' operand.
297   uint32_t getAddrMode5OpValue(const MCInst &MI, unsigned OpIdx,
298                                SmallVectorImpl<MCFixup> &Fixups,
299                                const MCSubtargetInfo &STI) const;
300 
301   /// getAddrMode5FP16OpValue - Return encoding info for 'reg +/- (imm8 << 1)' operand.
302   uint32_t getAddrMode5FP16OpValue(const MCInst &MI, unsigned OpIdx,
303                                SmallVectorImpl<MCFixup> &Fixups,
304                                const MCSubtargetInfo &STI) const;
305 
306   /// getCCOutOpValue - Return encoding of the 's' bit.
307   unsigned getCCOutOpValue(const MCInst &MI, unsigned Op,
308                            SmallVectorImpl<MCFixup> &Fixups,
309                            const MCSubtargetInfo &STI) const {
310     // The operand is either reg0 or CPSR. The 's' bit is encoded as '0' or
311     // '1' respectively.
312     return MI.getOperand(Op).getReg() == ARM::CPSR;
313   }
314 
315   unsigned getModImmOpValue(const MCInst &MI, unsigned Op,
316                             SmallVectorImpl<MCFixup> &Fixups,
317                             const MCSubtargetInfo &ST) const {
318     const MCOperand &MO = MI.getOperand(Op);
319 
320     // Support for fixups (MCFixup)
321     if (MO.isExpr()) {
322       const MCExpr *Expr = MO.getExpr();
323       // Fixups resolve to plain values that need to be encoded.
324       MCFixupKind Kind = MCFixupKind(ARM::fixup_arm_mod_imm);
325       Fixups.push_back(MCFixup::create(0, Expr, Kind, MI.getLoc()));
326       return 0;
327     }
328 
329     // Immediate is already in its encoded format
330     return MO.getImm();
331   }
332 
333   /// getT2SOImmOpValue - Return an encoded 12-bit shifted-immediate value.
334   unsigned getT2SOImmOpValue(const MCInst &MI, unsigned Op,
335                            SmallVectorImpl<MCFixup> &Fixups,
336                            const MCSubtargetInfo &STI) const {
337     const MCOperand &MO = MI.getOperand(Op);
338 
339     // Support for fixups (MCFixup)
340     if (MO.isExpr()) {
341       const MCExpr *Expr = MO.getExpr();
342       // Fixups resolve to plain values that need to be encoded.
343       MCFixupKind Kind = MCFixupKind(ARM::fixup_t2_so_imm);
344       Fixups.push_back(MCFixup::create(0, Expr, Kind, MI.getLoc()));
345       return 0;
346     }
347     unsigned SoImm = MO.getImm();
348     unsigned Encoded =  ARM_AM::getT2SOImmVal(SoImm);
349     assert(Encoded != ~0U && "Not a Thumb2 so_imm value?");
350     return Encoded;
351   }
352 
353   unsigned getT2AddrModeSORegOpValue(const MCInst &MI, unsigned OpNum,
354     SmallVectorImpl<MCFixup> &Fixups,
355     const MCSubtargetInfo &STI) const;
356   template<unsigned Bits, unsigned Shift>
357   unsigned getT2AddrModeImmOpValue(const MCInst &MI, unsigned OpNum,
358     SmallVectorImpl<MCFixup> &Fixups,
359     const MCSubtargetInfo &STI) const;
360   unsigned getT2AddrModeImm8OffsetOpValue(const MCInst &MI, unsigned OpNum,
361     SmallVectorImpl<MCFixup> &Fixups,
362     const MCSubtargetInfo &STI) const;
363 
364   /// getSORegOpValue - Return an encoded so_reg shifted register value.
365   unsigned getSORegRegOpValue(const MCInst &MI, unsigned Op,
366                            SmallVectorImpl<MCFixup> &Fixups,
367                            const MCSubtargetInfo &STI) const;
368   unsigned getSORegImmOpValue(const MCInst &MI, unsigned Op,
369                            SmallVectorImpl<MCFixup> &Fixups,
370                            const MCSubtargetInfo &STI) const;
371   unsigned getT2SORegOpValue(const MCInst &MI, unsigned Op,
372                              SmallVectorImpl<MCFixup> &Fixups,
373                              const MCSubtargetInfo &STI) const;
374 
375   unsigned getNEONVcvtImm32OpValue(const MCInst &MI, unsigned Op,
376                                    SmallVectorImpl<MCFixup> &Fixups,
377                                    const MCSubtargetInfo &STI) const {
378     return 64 - MI.getOperand(Op).getImm();
379   }
380 
381   unsigned getBitfieldInvertedMaskOpValue(const MCInst &MI, unsigned Op,
382                                       SmallVectorImpl<MCFixup> &Fixups,
383                                       const MCSubtargetInfo &STI) const;
384 
385   unsigned getRegisterListOpValue(const MCInst &MI, unsigned Op,
386                                   SmallVectorImpl<MCFixup> &Fixups,
387                                   const MCSubtargetInfo &STI) const;
388   unsigned getAddrMode6AddressOpValue(const MCInst &MI, unsigned Op,
389                                       SmallVectorImpl<MCFixup> &Fixups,
390                                       const MCSubtargetInfo &STI) const;
391   unsigned getAddrMode6OneLane32AddressOpValue(const MCInst &MI, unsigned Op,
392                                         SmallVectorImpl<MCFixup> &Fixups,
393                                         const MCSubtargetInfo &STI) const;
394   unsigned getAddrMode6DupAddressOpValue(const MCInst &MI, unsigned Op,
395                                         SmallVectorImpl<MCFixup> &Fixups,
396                                         const MCSubtargetInfo &STI) const;
397   unsigned getAddrMode6OffsetOpValue(const MCInst &MI, unsigned Op,
398                                      SmallVectorImpl<MCFixup> &Fixups,
399                                      const MCSubtargetInfo &STI) const;
400 
401   unsigned getShiftRight8Imm(const MCInst &MI, unsigned Op,
402                              SmallVectorImpl<MCFixup> &Fixups,
403                              const MCSubtargetInfo &STI) const;
404   unsigned getShiftRight16Imm(const MCInst &MI, unsigned Op,
405                               SmallVectorImpl<MCFixup> &Fixups,
406                               const MCSubtargetInfo &STI) const;
407   unsigned getShiftRight32Imm(const MCInst &MI, unsigned Op,
408                               SmallVectorImpl<MCFixup> &Fixups,
409                               const MCSubtargetInfo &STI) const;
410   unsigned getShiftRight64Imm(const MCInst &MI, unsigned Op,
411                               SmallVectorImpl<MCFixup> &Fixups,
412                               const MCSubtargetInfo &STI) const;
413 
414   unsigned getThumbSRImmOpValue(const MCInst &MI, unsigned Op,
415                                  SmallVectorImpl<MCFixup> &Fixups,
416                                  const MCSubtargetInfo &STI) const;
417 
418   unsigned NEONThumb2DataIPostEncoder(const MCInst &MI,
419                                       unsigned EncodedValue,
420                                       const MCSubtargetInfo &STI) const;
421   unsigned NEONThumb2LoadStorePostEncoder(const MCInst &MI,
422                                           unsigned EncodedValue,
423                                           const MCSubtargetInfo &STI) const;
424   unsigned NEONThumb2DupPostEncoder(const MCInst &MI,
425                                     unsigned EncodedValue,
426                                     const MCSubtargetInfo &STI) const;
427   unsigned NEONThumb2V8PostEncoder(const MCInst &MI,
428                                    unsigned EncodedValue,
429                                    const MCSubtargetInfo &STI) const;
430 
431   unsigned VFPThumb2PostEncoder(const MCInst &MI,
432                                 unsigned EncodedValue,
433                                 const MCSubtargetInfo &STI) const;
434 
435   uint32_t getPowerTwoOpValue(const MCInst &MI, unsigned OpIdx,
436                               SmallVectorImpl<MCFixup> &Fixups,
437                               const MCSubtargetInfo &STI) const;
438 
439   void EmitByte(unsigned char C, raw_ostream &OS) const {
440     OS << (char)C;
441   }
442 
443   void EmitConstant(uint64_t Val, unsigned Size, raw_ostream &OS) const {
444     // Output the constant in little endian byte order.
445     for (unsigned i = 0; i != Size; ++i) {
446       unsigned Shift = IsLittleEndian ? i * 8 : (Size - 1 - i) * 8;
447       EmitByte((Val >> Shift) & 0xff, OS);
448     }
449   }
450 
451   void encodeInstruction(const MCInst &MI, raw_ostream &OS,
452                          SmallVectorImpl<MCFixup> &Fixups,
453                          const MCSubtargetInfo &STI) const override;
454 
455   template <bool isNeg, ARM::Fixups fixup>
456   uint32_t getBFTargetOpValue(const MCInst &MI, unsigned OpIdx,
457                               SmallVectorImpl<MCFixup> &Fixups,
458                               const MCSubtargetInfo &STI) const;
459 
460   uint32_t getBFAfterTargetOpValue(const MCInst &MI, unsigned OpIdx,
461                                    SmallVectorImpl<MCFixup> &Fixups,
462                                    const MCSubtargetInfo &STI) const;
463 
464   uint32_t getVPTMaskOpValue(const MCInst &MI, unsigned OpIdx,
465                              SmallVectorImpl<MCFixup> &Fixups,
466                              const MCSubtargetInfo &STI) const;
467   uint32_t getRestrictedCondCodeOpValue(const MCInst &MI, unsigned OpIdx,
468                                         SmallVectorImpl<MCFixup> &Fixups,
469                                         const MCSubtargetInfo &STI) const;
470   template <unsigned size>
471   uint32_t getMVEPairVectorIndexOpValue(const MCInst &MI, unsigned OpIdx,
472                                         SmallVectorImpl<MCFixup> &Fixups,
473                                         const MCSubtargetInfo &STI) const;
474 };
475 
476 } // end anonymous namespace
477 
478 /// NEONThumb2DataIPostEncoder - Post-process encoded NEON data-processing
479 /// instructions, and rewrite them to their Thumb2 form if we are currently in
480 /// Thumb2 mode.
481 unsigned ARMMCCodeEmitter::NEONThumb2DataIPostEncoder(const MCInst &MI,
482                                                  unsigned EncodedValue,
483                                                  const MCSubtargetInfo &STI) const {
484   if (isThumb2(STI)) {
485     // NEON Thumb2 data-processsing encodings are very simple: bit 24 is moved
486     // to bit 12 of the high half-word (i.e. bit 28), and bits 27-24 are
487     // set to 1111.
488     unsigned Bit24 = EncodedValue & 0x01000000;
489     unsigned Bit28 = Bit24 << 4;
490     EncodedValue &= 0xEFFFFFFF;
491     EncodedValue |= Bit28;
492     EncodedValue |= 0x0F000000;
493   }
494 
495   return EncodedValue;
496 }
497 
498 /// NEONThumb2LoadStorePostEncoder - Post-process encoded NEON load/store
499 /// instructions, and rewrite them to their Thumb2 form if we are currently in
500 /// Thumb2 mode.
501 unsigned ARMMCCodeEmitter::NEONThumb2LoadStorePostEncoder(const MCInst &MI,
502                                                  unsigned EncodedValue,
503                                                  const MCSubtargetInfo &STI) const {
504   if (isThumb2(STI)) {
505     EncodedValue &= 0xF0FFFFFF;
506     EncodedValue |= 0x09000000;
507   }
508 
509   return EncodedValue;
510 }
511 
512 /// NEONThumb2DupPostEncoder - Post-process encoded NEON vdup
513 /// instructions, and rewrite them to their Thumb2 form if we are currently in
514 /// Thumb2 mode.
515 unsigned ARMMCCodeEmitter::NEONThumb2DupPostEncoder(const MCInst &MI,
516                                                  unsigned EncodedValue,
517                                                  const MCSubtargetInfo &STI) const {
518   if (isThumb2(STI)) {
519     EncodedValue &= 0x00FFFFFF;
520     EncodedValue |= 0xEE000000;
521   }
522 
523   return EncodedValue;
524 }
525 
526 /// Post-process encoded NEON v8 instructions, and rewrite them to Thumb2 form
527 /// if we are in Thumb2.
528 unsigned ARMMCCodeEmitter::NEONThumb2V8PostEncoder(const MCInst &MI,
529                                                  unsigned EncodedValue,
530                                                  const MCSubtargetInfo &STI) const {
531   if (isThumb2(STI)) {
532     EncodedValue |= 0xC000000; // Set bits 27-26
533   }
534 
535   return EncodedValue;
536 }
537 
538 /// VFPThumb2PostEncoder - Post-process encoded VFP instructions and rewrite
539 /// them to their Thumb2 form if we are currently in Thumb2 mode.
540 unsigned ARMMCCodeEmitter::
541 VFPThumb2PostEncoder(const MCInst &MI, unsigned EncodedValue,
542                      const MCSubtargetInfo &STI) const {
543   if (isThumb2(STI)) {
544     EncodedValue &= 0x0FFFFFFF;
545     EncodedValue |= 0xE0000000;
546   }
547   return EncodedValue;
548 }
549 
550 /// getMachineOpValue - Return binary encoding of operand. If the machine
551 /// operand requires relocation, record the relocation and return zero.
552 unsigned ARMMCCodeEmitter::
553 getMachineOpValue(const MCInst &MI, const MCOperand &MO,
554                   SmallVectorImpl<MCFixup> &Fixups,
555                   const MCSubtargetInfo &STI) const {
556   if (MO.isReg()) {
557     unsigned Reg = MO.getReg();
558     unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(Reg);
559 
560     // In NEON, Q registers are encoded as 2x their register number,
561     // because they're using the same indices as the D registers they
562     // overlap. In MVE, there are no 64-bit vector instructions, so
563     // the encodings all refer to Q-registers by their literal
564     // register number.
565 
566     if (STI.hasFeature(ARM::HasMVEIntegerOps))
567       return RegNo;
568 
569     switch (Reg) {
570     default:
571       return RegNo;
572     case ARM::Q0:  case ARM::Q1:  case ARM::Q2:  case ARM::Q3:
573     case ARM::Q4:  case ARM::Q5:  case ARM::Q6:  case ARM::Q7:
574     case ARM::Q8:  case ARM::Q9:  case ARM::Q10: case ARM::Q11:
575     case ARM::Q12: case ARM::Q13: case ARM::Q14: case ARM::Q15:
576       return 2 * RegNo;
577     }
578   } else if (MO.isImm()) {
579     return static_cast<unsigned>(MO.getImm());
580   } else if (MO.isDFPImm()) {
581     return static_cast<unsigned>(APFloat(bit_cast<double>(MO.getDFPImm()))
582                                      .bitcastToAPInt()
583                                      .getHiBits(32)
584                                      .getLimitedValue());
585   }
586 
587   llvm_unreachable("Unable to encode MCOperand!");
588 }
589 
590 /// getAddrModeImmOpValue - Return encoding info for 'reg +/- imm' operand.
591 bool ARMMCCodeEmitter::
592 EncodeAddrModeOpValues(const MCInst &MI, unsigned OpIdx, unsigned &Reg,
593                        unsigned &Imm, SmallVectorImpl<MCFixup> &Fixups,
594                        const MCSubtargetInfo &STI) const {
595   const MCOperand &MO  = MI.getOperand(OpIdx);
596   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
597 
598   Reg = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
599 
600   int32_t SImm = MO1.getImm();
601   bool isAdd = true;
602 
603   // Special value for #-0
604   if (SImm == INT32_MIN) {
605     SImm = 0;
606     isAdd = false;
607   }
608 
609   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
610   if (SImm < 0) {
611     SImm = -SImm;
612     isAdd = false;
613   }
614 
615   Imm = SImm;
616   return isAdd;
617 }
618 
619 /// getBranchTargetOpValue - Helper function to get the branch target operand,
620 /// which is either an immediate or requires a fixup.
621 static uint32_t getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
622                                        unsigned FixupKind,
623                                        SmallVectorImpl<MCFixup> &Fixups,
624                                        const MCSubtargetInfo &STI) {
625   const MCOperand &MO = MI.getOperand(OpIdx);
626 
627   // If the destination is an immediate, we have nothing to do.
628   if (MO.isImm()) return MO.getImm();
629   assert(MO.isExpr() && "Unexpected branch target type!");
630   const MCExpr *Expr = MO.getExpr();
631   MCFixupKind Kind = MCFixupKind(FixupKind);
632   Fixups.push_back(MCFixup::create(0, Expr, Kind, MI.getLoc()));
633 
634   // All of the information is in the fixup.
635   return 0;
636 }
637 
638 // Thumb BL and BLX use a strange offset encoding where bits 22 and 21 are
639 // determined by negating them and XOR'ing them with bit 23.
640 static int32_t encodeThumbBLOffset(int32_t offset) {
641   offset >>= 1;
642   uint32_t S  = (offset & 0x800000) >> 23;
643   uint32_t J1 = (offset & 0x400000) >> 22;
644   uint32_t J2 = (offset & 0x200000) >> 21;
645   J1 = (~J1 & 0x1);
646   J2 = (~J2 & 0x1);
647   J1 ^= S;
648   J2 ^= S;
649 
650   offset &= ~0x600000;
651   offset |= J1 << 22;
652   offset |= J2 << 21;
653 
654   return offset;
655 }
656 
657 /// getThumbBLTargetOpValue - Return encoding info for immediate branch target.
658 uint32_t ARMMCCodeEmitter::
659 getThumbBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
660                         SmallVectorImpl<MCFixup> &Fixups,
661                         const MCSubtargetInfo &STI) const {
662   const MCOperand MO = MI.getOperand(OpIdx);
663   if (MO.isExpr())
664     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_bl,
665                                     Fixups, STI);
666   return encodeThumbBLOffset(MO.getImm());
667 }
668 
669 /// getThumbBLXTargetOpValue - Return encoding info for Thumb immediate
670 /// BLX branch target.
671 uint32_t ARMMCCodeEmitter::
672 getThumbBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
673                          SmallVectorImpl<MCFixup> &Fixups,
674                          const MCSubtargetInfo &STI) const {
675   const MCOperand MO = MI.getOperand(OpIdx);
676   if (MO.isExpr())
677     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_blx,
678                                     Fixups, STI);
679   return encodeThumbBLOffset(MO.getImm());
680 }
681 
682 /// getThumbBRTargetOpValue - Return encoding info for Thumb branch target.
683 uint32_t ARMMCCodeEmitter::
684 getThumbBRTargetOpValue(const MCInst &MI, unsigned OpIdx,
685                         SmallVectorImpl<MCFixup> &Fixups,
686                         const MCSubtargetInfo &STI) const {
687   const MCOperand MO = MI.getOperand(OpIdx);
688   if (MO.isExpr())
689     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_br,
690                                     Fixups, STI);
691   return (MO.getImm() >> 1);
692 }
693 
694 /// getThumbBCCTargetOpValue - Return encoding info for Thumb branch target.
695 uint32_t ARMMCCodeEmitter::
696 getThumbBCCTargetOpValue(const MCInst &MI, unsigned OpIdx,
697                          SmallVectorImpl<MCFixup> &Fixups,
698                          const MCSubtargetInfo &STI) const {
699   const MCOperand MO = MI.getOperand(OpIdx);
700   if (MO.isExpr())
701     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_bcc,
702                                     Fixups, STI);
703   return (MO.getImm() >> 1);
704 }
705 
706 /// getThumbCBTargetOpValue - Return encoding info for Thumb branch target.
707 uint32_t ARMMCCodeEmitter::
708 getThumbCBTargetOpValue(const MCInst &MI, unsigned OpIdx,
709                         SmallVectorImpl<MCFixup> &Fixups,
710                         const MCSubtargetInfo &STI) const {
711   const MCOperand MO = MI.getOperand(OpIdx);
712   if (MO.isExpr())
713     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_cb, Fixups, STI);
714   return (MO.getImm() >> 1);
715 }
716 
717 /// Return true if this branch has a non-always predication
718 static bool HasConditionalBranch(const MCInst &MI) {
719   int NumOp = MI.getNumOperands();
720   if (NumOp >= 2) {
721     for (int i = 0; i < NumOp-1; ++i) {
722       const MCOperand &MCOp1 = MI.getOperand(i);
723       const MCOperand &MCOp2 = MI.getOperand(i + 1);
724       if (MCOp1.isImm() && MCOp2.isReg() &&
725           (MCOp2.getReg() == 0 || MCOp2.getReg() == ARM::CPSR)) {
726         if (ARMCC::CondCodes(MCOp1.getImm()) != ARMCC::AL)
727           return true;
728       }
729     }
730   }
731   return false;
732 }
733 
734 /// getBranchTargetOpValue - Return encoding info for 24-bit immediate branch
735 /// target.
736 uint32_t ARMMCCodeEmitter::
737 getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
738                        SmallVectorImpl<MCFixup> &Fixups,
739                        const MCSubtargetInfo &STI) const {
740   // FIXME: This really, really shouldn't use TargetMachine. We don't want
741   // coupling between MC and TM anywhere we can help it.
742   if (isThumb2(STI))
743     return
744       ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_condbranch, Fixups, STI);
745   return getARMBranchTargetOpValue(MI, OpIdx, Fixups, STI);
746 }
747 
748 /// getBranchTargetOpValue - Return encoding info for 24-bit immediate branch
749 /// target.
750 uint32_t ARMMCCodeEmitter::
751 getARMBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
752                           SmallVectorImpl<MCFixup> &Fixups,
753                           const MCSubtargetInfo &STI) const {
754   const MCOperand MO = MI.getOperand(OpIdx);
755   if (MO.isExpr()) {
756     if (HasConditionalBranch(MI))
757       return ::getBranchTargetOpValue(MI, OpIdx,
758                                       ARM::fixup_arm_condbranch, Fixups, STI);
759     return ::getBranchTargetOpValue(MI, OpIdx,
760                                     ARM::fixup_arm_uncondbranch, Fixups, STI);
761   }
762 
763   return MO.getImm() >> 2;
764 }
765 
766 uint32_t ARMMCCodeEmitter::
767 getARMBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
768                           SmallVectorImpl<MCFixup> &Fixups,
769                           const MCSubtargetInfo &STI) const {
770   const MCOperand MO = MI.getOperand(OpIdx);
771   if (MO.isExpr()) {
772     if (HasConditionalBranch(MI))
773       return ::getBranchTargetOpValue(MI, OpIdx,
774                                       ARM::fixup_arm_condbl, Fixups, STI);
775     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_uncondbl, Fixups, STI);
776   }
777 
778   return MO.getImm() >> 2;
779 }
780 
781 uint32_t ARMMCCodeEmitter::
782 getARMBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
783                           SmallVectorImpl<MCFixup> &Fixups,
784                           const MCSubtargetInfo &STI) const {
785   const MCOperand MO = MI.getOperand(OpIdx);
786   if (MO.isExpr())
787     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_blx, Fixups, STI);
788 
789   return MO.getImm() >> 1;
790 }
791 
792 /// getUnconditionalBranchTargetOpValue - Return encoding info for 24-bit
793 /// immediate branch target.
794 uint32_t ARMMCCodeEmitter::getThumbBranchTargetOpValue(
795     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
796     const MCSubtargetInfo &STI) const {
797   unsigned Val = 0;
798   const MCOperand MO = MI.getOperand(OpIdx);
799 
800   if(MO.isExpr())
801     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_uncondbranch, Fixups, STI);
802   else
803     Val = MO.getImm() >> 1;
804 
805   bool I  = (Val & 0x800000);
806   bool J1 = (Val & 0x400000);
807   bool J2 = (Val & 0x200000);
808   if (I ^ J1)
809     Val &= ~0x400000;
810   else
811     Val |= 0x400000;
812 
813   if (I ^ J2)
814     Val &= ~0x200000;
815   else
816     Val |= 0x200000;
817 
818   return Val;
819 }
820 
821 /// getAdrLabelOpValue - Return encoding info for 12-bit shifted-immediate
822 /// ADR label target.
823 uint32_t ARMMCCodeEmitter::
824 getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
825                    SmallVectorImpl<MCFixup> &Fixups,
826                    const MCSubtargetInfo &STI) const {
827   const MCOperand MO = MI.getOperand(OpIdx);
828   if (MO.isExpr())
829     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_adr_pcrel_12,
830                                     Fixups, STI);
831   int64_t offset = MO.getImm();
832   uint32_t Val = 0x2000;
833 
834   int SoImmVal;
835   if (offset == INT32_MIN) {
836     Val = 0x1000;
837     SoImmVal = 0;
838   } else if (offset < 0) {
839     Val = 0x1000;
840     offset *= -1;
841     SoImmVal = ARM_AM::getSOImmVal(offset);
842     if(SoImmVal == -1) {
843       Val = 0x2000;
844       offset *= -1;
845       SoImmVal = ARM_AM::getSOImmVal(offset);
846     }
847   } else {
848     SoImmVal = ARM_AM::getSOImmVal(offset);
849     if(SoImmVal == -1) {
850       Val = 0x1000;
851       offset *= -1;
852       SoImmVal = ARM_AM::getSOImmVal(offset);
853     }
854   }
855 
856   assert(SoImmVal != -1 && "Not a valid so_imm value!");
857 
858   Val |= SoImmVal;
859   return Val;
860 }
861 
862 /// getT2AdrLabelOpValue - Return encoding info for 12-bit immediate ADR label
863 /// target.
864 uint32_t ARMMCCodeEmitter::
865 getT2AdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
866                    SmallVectorImpl<MCFixup> &Fixups,
867                    const MCSubtargetInfo &STI) const {
868   const MCOperand MO = MI.getOperand(OpIdx);
869   if (MO.isExpr())
870     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_adr_pcrel_12,
871                                     Fixups, STI);
872   int32_t Val = MO.getImm();
873   if (Val == INT32_MIN)
874     Val = 0x1000;
875   else if (Val < 0) {
876     Val *= -1;
877     Val |= 0x1000;
878   }
879   return Val;
880 }
881 
882 /// getITMaskOpValue - Return the architectural encoding of an IT
883 /// predication mask, given the MCOperand format.
884 uint32_t ARMMCCodeEmitter::
885 getITMaskOpValue(const MCInst &MI, unsigned OpIdx,
886                  SmallVectorImpl<MCFixup> &Fixups,
887                  const MCSubtargetInfo &STI) const {
888   const MCOperand MaskMO = MI.getOperand(OpIdx);
889   assert(MaskMO.isImm() && "Unexpected operand type!");
890 
891   unsigned Mask = MaskMO.getImm();
892 
893   // IT masks are encoded as a sequence of replacement low-order bits
894   // for the condition code. So if the low bit of the starting
895   // condition code is 1, then we have to flip all the bits above the
896   // terminating bit (which is the lowest 1 bit).
897   assert(OpIdx > 0 && "IT mask appears first!");
898   const MCOperand CondMO = MI.getOperand(OpIdx-1);
899   assert(CondMO.isImm() && "Unexpected operand type!");
900   if (CondMO.getImm() & 1) {
901     unsigned LowBit = Mask & -Mask;
902     unsigned BitsAboveLowBit = 0xF & (-LowBit << 1);
903     Mask ^= BitsAboveLowBit;
904   }
905 
906   return Mask;
907 }
908 
909 /// getThumbAdrLabelOpValue - Return encoding info for 8-bit immediate ADR label
910 /// target.
911 uint32_t ARMMCCodeEmitter::
912 getThumbAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
913                    SmallVectorImpl<MCFixup> &Fixups,
914                    const MCSubtargetInfo &STI) const {
915   const MCOperand MO = MI.getOperand(OpIdx);
916   if (MO.isExpr())
917     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_thumb_adr_pcrel_10,
918                                     Fixups, STI);
919   return MO.getImm();
920 }
921 
922 /// getThumbAddrModeRegRegOpValue - Return encoding info for 'reg + reg'
923 /// operand.
924 uint32_t ARMMCCodeEmitter::
925 getThumbAddrModeRegRegOpValue(const MCInst &MI, unsigned OpIdx,
926                               SmallVectorImpl<MCFixup> &,
927                               const MCSubtargetInfo &STI) const {
928   // [Rn, Rm]
929   //   {5-3} = Rm
930   //   {2-0} = Rn
931   const MCOperand &MO1 = MI.getOperand(OpIdx);
932   const MCOperand &MO2 = MI.getOperand(OpIdx + 1);
933   unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
934   unsigned Rm = CTX.getRegisterInfo()->getEncodingValue(MO2.getReg());
935   return (Rm << 3) | Rn;
936 }
937 
938 /// getMVEShiftImmOpValue - Return encoding info for the 'sz:imm5'
939 /// operand.
940 uint32_t
941 ARMMCCodeEmitter::getMVEShiftImmOpValue(const MCInst &MI, unsigned OpIdx,
942                                         SmallVectorImpl<MCFixup> &Fixups,
943                                         const MCSubtargetInfo &STI) const {
944   // {4-0} = szimm5
945   // The value we are trying to encode is an immediate between either the
946   // range of [1-7] or [1-15] depending on whether we are dealing with the
947   // u8/s8 or the u16/s16 variants respectively.
948   // This value is encoded as follows, if ShiftImm is the value within those
949   // ranges then the encoding szimm5 = ShiftImm + size, where size is either 8
950   // or 16.
951 
952   unsigned Size, ShiftImm;
953   switch(MI.getOpcode()) {
954     case ARM::MVE_VSHLL_imms16bh:
955     case ARM::MVE_VSHLL_imms16th:
956     case ARM::MVE_VSHLL_immu16bh:
957     case ARM::MVE_VSHLL_immu16th:
958       Size = 16;
959       break;
960     case ARM::MVE_VSHLL_imms8bh:
961     case ARM::MVE_VSHLL_imms8th:
962     case ARM::MVE_VSHLL_immu8bh:
963     case ARM::MVE_VSHLL_immu8th:
964       Size = 8;
965       break;
966     default:
967       llvm_unreachable("Use of operand not supported by this instruction");
968   }
969   ShiftImm = MI.getOperand(OpIdx).getImm();
970   return Size + ShiftImm;
971 }
972 
973 /// getAddrModeImm12OpValue - Return encoding info for 'reg +/- imm12' operand.
974 uint32_t ARMMCCodeEmitter::
975 getAddrModeImm12OpValue(const MCInst &MI, unsigned OpIdx,
976                         SmallVectorImpl<MCFixup> &Fixups,
977                         const MCSubtargetInfo &STI) const {
978   // {17-13} = reg
979   // {12}    = (U)nsigned (add == '1', sub == '0')
980   // {11-0}  = imm12
981   unsigned Reg = 0, Imm12 = 0;
982   bool isAdd = true;
983   // If The first operand isn't a register, we have a label reference.
984   const MCOperand &MO = MI.getOperand(OpIdx);
985   if (MO.isReg()) {
986     const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
987     if (MO1.isImm()) {
988       isAdd = EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm12, Fixups, STI);
989     } else if (MO1.isExpr()) {
990       assert(!isThumb(STI) && !isThumb2(STI) &&
991              "Thumb mode requires different encoding");
992       Reg = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
993       isAdd = false; // 'U' bit is set as part of the fixup.
994       MCFixupKind Kind = MCFixupKind(ARM::fixup_arm_ldst_abs_12);
995       Fixups.push_back(MCFixup::create(0, MO1.getExpr(), Kind, MI.getLoc()));
996     }
997   } else if (MO.isExpr()) {
998     Reg = CTX.getRegisterInfo()->getEncodingValue(ARM::PC); // Rn is PC.
999     isAdd = false; // 'U' bit is set as part of the fixup.
1000     MCFixupKind Kind;
1001     if (isThumb2(STI))
1002       Kind = MCFixupKind(ARM::fixup_t2_ldst_pcrel_12);
1003     else
1004       Kind = MCFixupKind(ARM::fixup_arm_ldst_pcrel_12);
1005     Fixups.push_back(MCFixup::create(0, MO.getExpr(), Kind, MI.getLoc()));
1006 
1007     ++MCNumCPRelocations;
1008   } else {
1009     Reg = ARM::PC;
1010     int32_t Offset = MO.getImm();
1011     if (Offset == INT32_MIN) {
1012       Offset = 0;
1013       isAdd = false;
1014     } else if (Offset < 0) {
1015       Offset *= -1;
1016       isAdd = false;
1017     }
1018     Imm12 = Offset;
1019   }
1020   uint32_t Binary = Imm12 & 0xfff;
1021   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1022   if (isAdd)
1023     Binary |= (1 << 12);
1024   Binary |= (Reg << 13);
1025   return Binary;
1026 }
1027 
1028 template<unsigned Bits, unsigned Shift>
1029 uint32_t ARMMCCodeEmitter::
1030 getT2ScaledImmOpValue(const MCInst &MI, unsigned OpIdx,
1031                       SmallVectorImpl<MCFixup> &Fixups,
1032                       const MCSubtargetInfo &STI) const {
1033   // FIXME: The immediate operand should have already been encoded like this
1034   // before ever getting here. The encoder method should just need to combine
1035   // the MI operands for the register and the offset into a single
1036   // representation for the complex operand in the .td file. This isn't just
1037   // style, unfortunately. As-is, we can't represent the distinct encoding
1038   // for #-0.
1039 
1040   // {Bits}    = (U)nsigned (add == '1', sub == '0')
1041   // {(Bits-1)-0}  = immediate
1042   int32_t Imm = MI.getOperand(OpIdx).getImm();
1043   bool isAdd = Imm >= 0;
1044 
1045   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1046   if (Imm < 0)
1047     Imm = -(uint32_t)Imm;
1048 
1049   Imm >>= Shift;
1050 
1051   uint32_t Binary = Imm & ((1U << Bits) - 1);
1052   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1053   if (isAdd)
1054     Binary |= (1U << Bits);
1055   return Binary;
1056 }
1057 
1058 /// getMveAddrModeRQOpValue - Return encoding info for 'reg, vreg'
1059 /// operand.
1060 uint32_t ARMMCCodeEmitter::
1061 getMveAddrModeRQOpValue(const MCInst &MI, unsigned OpIdx,
1062                         SmallVectorImpl<MCFixup> &Fixups,
1063                         const MCSubtargetInfo &STI) const {
1064     // {6-3} Rn
1065     // {2-0} Qm
1066     const MCOperand &M0 = MI.getOperand(OpIdx);
1067     const MCOperand &M1 = MI.getOperand(OpIdx + 1);
1068 
1069     unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(M0.getReg());
1070     unsigned Qm = CTX.getRegisterInfo()->getEncodingValue(M1.getReg());
1071 
1072     assert(Qm < 8 && "Qm is supposed to be encodable in 3 bits");
1073 
1074     return (Rn << 3) | Qm;
1075 }
1076 
1077 /// getMveAddrModeRQOpValue - Return encoding info for 'reg, vreg'
1078 /// operand.
1079 template<int shift>
1080 uint32_t ARMMCCodeEmitter::
1081 getMveAddrModeQOpValue(const MCInst &MI, unsigned OpIdx,
1082                         SmallVectorImpl<MCFixup> &Fixups,
1083                         const MCSubtargetInfo &STI) const {
1084     // {10-8} Qm
1085     // {7-0} Imm
1086     const MCOperand &M0 = MI.getOperand(OpIdx);
1087     const MCOperand &M1 = MI.getOperand(OpIdx + 1);
1088 
1089     unsigned Qm = CTX.getRegisterInfo()->getEncodingValue(M0.getReg());
1090     int32_t Imm = M1.getImm();
1091 
1092     bool isAdd = Imm >= 0;
1093 
1094     Imm >>= shift;
1095 
1096     if (!isAdd)
1097       Imm = -(uint32_t)Imm;
1098 
1099     Imm &= 0x7f;
1100 
1101     if (isAdd)
1102       Imm |= 0x80;
1103 
1104     assert(Qm < 8 && "Qm is supposed to be encodable in 3 bits");
1105 
1106     return (Qm << 8) | Imm;
1107 }
1108 
1109 /// getT2AddrModeImm8s4OpValue - Return encoding info for
1110 /// 'reg +/- imm8<<2' operand.
1111 uint32_t ARMMCCodeEmitter::
1112 getT2AddrModeImm8s4OpValue(const MCInst &MI, unsigned OpIdx,
1113                         SmallVectorImpl<MCFixup> &Fixups,
1114                         const MCSubtargetInfo &STI) const {
1115   // {12-9} = reg
1116   // {8}    = (U)nsigned (add == '1', sub == '0')
1117   // {7-0}  = imm8
1118   unsigned Reg, Imm8;
1119   bool isAdd = true;
1120   // If The first operand isn't a register, we have a label reference.
1121   const MCOperand &MO = MI.getOperand(OpIdx);
1122   if (!MO.isReg()) {
1123     Reg = CTX.getRegisterInfo()->getEncodingValue(ARM::PC);   // Rn is PC.
1124     Imm8 = 0;
1125     isAdd = false ; // 'U' bit is set as part of the fixup.
1126 
1127     assert(MO.isExpr() && "Unexpected machine operand type!");
1128     const MCExpr *Expr = MO.getExpr();
1129     MCFixupKind Kind = MCFixupKind(ARM::fixup_t2_pcrel_10);
1130     Fixups.push_back(MCFixup::create(0, Expr, Kind, MI.getLoc()));
1131 
1132     ++MCNumCPRelocations;
1133   } else
1134     isAdd = EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm8, Fixups, STI);
1135 
1136   // FIXME: The immediate operand should have already been encoded like this
1137   // before ever getting here. The encoder method should just need to combine
1138   // the MI operands for the register and the offset into a single
1139   // representation for the complex operand in the .td file. This isn't just
1140   // style, unfortunately. As-is, we can't represent the distinct encoding
1141   // for #-0.
1142   assert(((Imm8 & 0x3) == 0) && "Not a valid immediate!");
1143   uint32_t Binary = (Imm8 >> 2) & 0xff;
1144   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1145   if (isAdd)
1146     Binary |= (1 << 8);
1147   Binary |= (Reg << 9);
1148   return Binary;
1149 }
1150 
1151 /// getT2AddrModeImm7s4OpValue - Return encoding info for
1152 /// 'reg +/- imm7<<2' operand.
1153 uint32_t
1154 ARMMCCodeEmitter::getT2AddrModeImm7s4OpValue(const MCInst &MI, unsigned OpIdx,
1155                                              SmallVectorImpl<MCFixup> &Fixups,
1156                                              const MCSubtargetInfo &STI) const {
1157   // {11-8} = reg
1158   // {7}    = (A)dd (add == '1', sub == '0')
1159   // {6-0}  = imm7
1160   unsigned Reg, Imm7;
1161   // If The first operand isn't a register, we have a label reference.
1162   bool isAdd = EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm7, Fixups, STI);
1163 
1164   // FIXME: The immediate operand should have already been encoded like this
1165   // before ever getting here. The encoder method should just need to combine
1166   // the MI operands for the register and the offset into a single
1167   // representation for the complex operand in the .td file. This isn't just
1168   // style, unfortunately. As-is, we can't represent the distinct encoding
1169   // for #-0.
1170   uint32_t Binary = (Imm7 >> 2) & 0xff;
1171   // Immediate is always encoded as positive. The 'A' bit controls add vs sub.
1172   if (isAdd)
1173     Binary |= (1 << 7);
1174   Binary |= (Reg << 8);
1175   return Binary;
1176 }
1177 
1178 /// getT2AddrModeImm0_1020s4OpValue - Return encoding info for
1179 /// 'reg + imm8<<2' operand.
1180 uint32_t ARMMCCodeEmitter::
1181 getT2AddrModeImm0_1020s4OpValue(const MCInst &MI, unsigned OpIdx,
1182                         SmallVectorImpl<MCFixup> &Fixups,
1183                         const MCSubtargetInfo &STI) const {
1184   // {11-8} = reg
1185   // {7-0}  = imm8
1186   const MCOperand &MO = MI.getOperand(OpIdx);
1187   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1188   unsigned Reg = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1189   unsigned Imm8 = MO1.getImm();
1190   return (Reg << 8) | Imm8;
1191 }
1192 
1193 uint32_t ARMMCCodeEmitter::getHiLoImmOpValue(const MCInst &MI, unsigned OpIdx,
1194                                              SmallVectorImpl<MCFixup> &Fixups,
1195                                              const MCSubtargetInfo &STI) const {
1196   // {20-16} = imm{15-12}
1197   // {11-0}  = imm{11-0}
1198   const MCOperand &MO = MI.getOperand(OpIdx);
1199   if (MO.isImm())
1200     // Hi / lo bits already extracted during earlier passes.
1201     return static_cast<unsigned>(MO.getImm());
1202 
1203   // Handle :upper16:, :lower16:, :upper8_15:, :upper0_7:, :lower8_15:
1204   // :lower0_7: assembly prefixes.
1205   const MCExpr *E = MO.getExpr();
1206   MCFixupKind Kind;
1207   if (E->getKind() == MCExpr::Target) {
1208     const ARMMCExpr *ARM16Expr = cast<ARMMCExpr>(E);
1209     E = ARM16Expr->getSubExpr();
1210 
1211     if (const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(E)) {
1212       const int64_t Value = MCE->getValue();
1213       if (Value > UINT32_MAX)
1214         report_fatal_error("constant value truncated (limited to 32-bit)");
1215 
1216       switch (ARM16Expr->getKind()) {
1217       case ARMMCExpr::VK_ARM_HI16:
1218         return (int32_t(Value) & 0xffff0000) >> 16;
1219       case ARMMCExpr::VK_ARM_LO16:
1220         return (int32_t(Value) & 0x0000ffff);
1221 
1222       case ARMMCExpr::VK_ARM_HI_8_15:
1223         return (int32_t(Value) & 0xff000000) >> 24;
1224       case ARMMCExpr::VK_ARM_HI_0_7:
1225         return (int32_t(Value) & 0x00ff0000) >> 16;
1226       case ARMMCExpr::VK_ARM_LO_8_15:
1227         return (int32_t(Value) & 0x0000ff00) >> 8;
1228       case ARMMCExpr::VK_ARM_LO_0_7:
1229         return (int32_t(Value) & 0x000000ff);
1230 
1231       default: llvm_unreachable("Unsupported ARMFixup");
1232       }
1233     }
1234 
1235     switch (ARM16Expr->getKind()) {
1236     default: llvm_unreachable("Unsupported ARMFixup");
1237     case ARMMCExpr::VK_ARM_HI16:
1238       Kind = MCFixupKind(isThumb(STI) ? ARM::fixup_t2_movt_hi16
1239                                       : ARM::fixup_arm_movt_hi16);
1240       break;
1241     case ARMMCExpr::VK_ARM_LO16:
1242       Kind = MCFixupKind(isThumb(STI) ? ARM::fixup_t2_movw_lo16
1243                                       : ARM::fixup_arm_movw_lo16);
1244       break;
1245     case ARMMCExpr::VK_ARM_HI_8_15:
1246       if (!isThumb(STI))
1247         llvm_unreachable(":upper_8_15: not supported in Arm state");
1248       Kind = MCFixupKind(ARM::fixup_arm_thumb_upper_8_15);
1249       break;
1250     case ARMMCExpr::VK_ARM_HI_0_7:
1251       if (!isThumb(STI))
1252         llvm_unreachable(":upper_0_7: not supported in Arm state");
1253       Kind = MCFixupKind(ARM::fixup_arm_thumb_upper_0_7);
1254       break;
1255     case ARMMCExpr::VK_ARM_LO_8_15:
1256       if (!isThumb(STI))
1257         llvm_unreachable(":lower_8_15: not supported in Arm state");
1258       Kind = MCFixupKind(ARM::fixup_arm_thumb_lower_8_15);
1259       break;
1260     case ARMMCExpr::VK_ARM_LO_0_7:
1261       if (!isThumb(STI))
1262         llvm_unreachable(":lower_0_7: not supported in Arm state");
1263       Kind = MCFixupKind(ARM::fixup_arm_thumb_lower_0_7);
1264       break;
1265     }
1266 
1267     Fixups.push_back(MCFixup::create(0, E, Kind, MI.getLoc()));
1268     return 0;
1269   }
1270   // If the expression doesn't have :upper16:, :lower16: on it, it's just a
1271   // plain immediate expression, previously those evaluated to the lower 16 bits
1272   // of the expression regardless of whether we have a movt or a movw, but that
1273   // led to misleadingly results.  This is disallowed in the AsmParser in
1274   // validateInstruction() so this should never happen.  The same holds for
1275   // thumb1 :upper8_15:, :upper0_7:, lower8_15: or :lower0_7: with movs or adds.
1276   llvm_unreachable("expression without :upper16:, :lower16:, :upper8_15:,"
1277                    ":upper0_7:, lower8_15: or :lower0_7:");
1278 }
1279 
1280 uint32_t ARMMCCodeEmitter::
1281 getLdStSORegOpValue(const MCInst &MI, unsigned OpIdx,
1282                     SmallVectorImpl<MCFixup> &Fixups,
1283                     const MCSubtargetInfo &STI) const {
1284   const MCOperand &MO = MI.getOperand(OpIdx);
1285   const MCOperand &MO1 = MI.getOperand(OpIdx+1);
1286   const MCOperand &MO2 = MI.getOperand(OpIdx+2);
1287   unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1288   unsigned Rm = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
1289   unsigned ShImm = ARM_AM::getAM2Offset(MO2.getImm());
1290   bool isAdd = ARM_AM::getAM2Op(MO2.getImm()) == ARM_AM::add;
1291   ARM_AM::ShiftOpc ShOp = ARM_AM::getAM2ShiftOpc(MO2.getImm());
1292   unsigned SBits = getShiftOp(ShOp);
1293 
1294   // While "lsr #32" and "asr #32" exist, they are encoded with a 0 in the shift
1295   // amount. However, it would be an easy mistake to make so check here.
1296   assert((ShImm & ~0x1f) == 0 && "Out of range shift amount");
1297 
1298   // {16-13} = Rn
1299   // {12}    = isAdd
1300   // {11-0}  = shifter
1301   //  {3-0}  = Rm
1302   //  {4}    = 0
1303   //  {6-5}  = type
1304   //  {11-7} = imm
1305   uint32_t Binary = Rm;
1306   Binary |= Rn << 13;
1307   Binary |= SBits << 5;
1308   Binary |= ShImm << 7;
1309   if (isAdd)
1310     Binary |= 1 << 12;
1311   return Binary;
1312 }
1313 
1314 uint32_t ARMMCCodeEmitter::
1315 getAddrMode2OffsetOpValue(const MCInst &MI, unsigned OpIdx,
1316                           SmallVectorImpl<MCFixup> &Fixups,
1317                           const MCSubtargetInfo &STI) const {
1318   // {13}     1 == imm12, 0 == Rm
1319   // {12}     isAdd
1320   // {11-0}   imm12/Rm
1321   const MCOperand &MO = MI.getOperand(OpIdx);
1322   const MCOperand &MO1 = MI.getOperand(OpIdx+1);
1323   unsigned Imm = MO1.getImm();
1324   bool isAdd = ARM_AM::getAM2Op(Imm) == ARM_AM::add;
1325   bool isReg = MO.getReg() != 0;
1326   uint32_t Binary = ARM_AM::getAM2Offset(Imm);
1327   // if reg +/- reg, Rm will be non-zero. Otherwise, we have reg +/- imm12
1328   if (isReg) {
1329     ARM_AM::ShiftOpc ShOp = ARM_AM::getAM2ShiftOpc(Imm);
1330     Binary <<= 7;                    // Shift amount is bits [11:7]
1331     Binary |= getShiftOp(ShOp) << 5; // Shift type is bits [6:5]
1332     Binary |= CTX.getRegisterInfo()->getEncodingValue(MO.getReg()); // Rm is bits [3:0]
1333   }
1334   return Binary | (isAdd << 12) | (isReg << 13);
1335 }
1336 
1337 uint32_t ARMMCCodeEmitter::
1338 getPostIdxRegOpValue(const MCInst &MI, unsigned OpIdx,
1339                      SmallVectorImpl<MCFixup> &Fixups,
1340                      const MCSubtargetInfo &STI) const {
1341   // {4}      isAdd
1342   // {3-0}    Rm
1343   const MCOperand &MO = MI.getOperand(OpIdx);
1344   const MCOperand &MO1 = MI.getOperand(OpIdx+1);
1345   bool isAdd = MO1.getImm() != 0;
1346   return CTX.getRegisterInfo()->getEncodingValue(MO.getReg()) | (isAdd << 4);
1347 }
1348 
1349 uint32_t ARMMCCodeEmitter::
1350 getAddrMode3OffsetOpValue(const MCInst &MI, unsigned OpIdx,
1351                           SmallVectorImpl<MCFixup> &Fixups,
1352                           const MCSubtargetInfo &STI) const {
1353   // {9}      1 == imm8, 0 == Rm
1354   // {8}      isAdd
1355   // {7-4}    imm7_4/zero
1356   // {3-0}    imm3_0/Rm
1357   const MCOperand &MO = MI.getOperand(OpIdx);
1358   const MCOperand &MO1 = MI.getOperand(OpIdx+1);
1359   unsigned Imm = MO1.getImm();
1360   bool isAdd = ARM_AM::getAM3Op(Imm) == ARM_AM::add;
1361   bool isImm = MO.getReg() == 0;
1362   uint32_t Imm8 = ARM_AM::getAM3Offset(Imm);
1363   // if reg +/- reg, Rm will be non-zero. Otherwise, we have reg +/- imm8
1364   if (!isImm)
1365     Imm8 = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1366   return Imm8 | (isAdd << 8) | (isImm << 9);
1367 }
1368 
1369 uint32_t ARMMCCodeEmitter::
1370 getAddrMode3OpValue(const MCInst &MI, unsigned OpIdx,
1371                     SmallVectorImpl<MCFixup> &Fixups,
1372                     const MCSubtargetInfo &STI) const {
1373   // {13}     1 == imm8, 0 == Rm
1374   // {12-9}   Rn
1375   // {8}      isAdd
1376   // {7-4}    imm7_4/zero
1377   // {3-0}    imm3_0/Rm
1378   const MCOperand &MO = MI.getOperand(OpIdx);
1379   const MCOperand &MO1 = MI.getOperand(OpIdx+1);
1380   const MCOperand &MO2 = MI.getOperand(OpIdx+2);
1381 
1382   // If The first operand isn't a register, we have a label reference.
1383   if (!MO.isReg()) {
1384     unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(ARM::PC);   // Rn is PC.
1385 
1386     assert(MO.isExpr() && "Unexpected machine operand type!");
1387     const MCExpr *Expr = MO.getExpr();
1388     MCFixupKind Kind = MCFixupKind(ARM::fixup_arm_pcrel_10_unscaled);
1389     Fixups.push_back(MCFixup::create(0, Expr, Kind, MI.getLoc()));
1390 
1391     ++MCNumCPRelocations;
1392     return (Rn << 9) | (1 << 13);
1393   }
1394   unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1395   unsigned Imm = MO2.getImm();
1396   bool isAdd = ARM_AM::getAM3Op(Imm) == ARM_AM::add;
1397   bool isImm = MO1.getReg() == 0;
1398   uint32_t Imm8 = ARM_AM::getAM3Offset(Imm);
1399   // if reg +/- reg, Rm will be non-zero. Otherwise, we have reg +/- imm8
1400   if (!isImm)
1401     Imm8 = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
1402   return (Rn << 9) | Imm8 | (isAdd << 8) | (isImm << 13);
1403 }
1404 
1405 /// getAddrModeThumbSPOpValue - Encode the t_addrmode_sp operands.
1406 uint32_t ARMMCCodeEmitter::
1407 getAddrModeThumbSPOpValue(const MCInst &MI, unsigned OpIdx,
1408                           SmallVectorImpl<MCFixup> &Fixups,
1409                           const MCSubtargetInfo &STI) const {
1410   // [SP, #imm]
1411   //   {7-0} = imm8
1412   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1413   assert(MI.getOperand(OpIdx).getReg() == ARM::SP &&
1414          "Unexpected base register!");
1415 
1416   // The immediate is already shifted for the implicit zeroes, so no change
1417   // here.
1418   return MO1.getImm() & 0xff;
1419 }
1420 
1421 /// getAddrModeISOpValue - Encode the t_addrmode_is# operands.
1422 uint32_t ARMMCCodeEmitter::
1423 getAddrModeISOpValue(const MCInst &MI, unsigned OpIdx,
1424                      SmallVectorImpl<MCFixup> &Fixups,
1425                      const MCSubtargetInfo &STI) const {
1426   // [Rn, #imm]
1427   //   {7-3} = imm5
1428   //   {2-0} = Rn
1429   const MCOperand &MO = MI.getOperand(OpIdx);
1430   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1431   unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1432   unsigned Imm5 = MO1.getImm();
1433   return ((Imm5 & 0x1f) << 3) | Rn;
1434 }
1435 
1436 /// getAddrModePCOpValue - Return encoding for t_addrmode_pc operands.
1437 uint32_t ARMMCCodeEmitter::
1438 getAddrModePCOpValue(const MCInst &MI, unsigned OpIdx,
1439                      SmallVectorImpl<MCFixup> &Fixups,
1440                      const MCSubtargetInfo &STI) const {
1441   const MCOperand MO = MI.getOperand(OpIdx);
1442   if (MO.isExpr())
1443     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_cp, Fixups, STI);
1444   return (MO.getImm() >> 2);
1445 }
1446 
1447 /// getAddrMode5OpValue - Return encoding info for 'reg +/- (imm8 << 2)' operand.
1448 uint32_t ARMMCCodeEmitter::
1449 getAddrMode5OpValue(const MCInst &MI, unsigned OpIdx,
1450                     SmallVectorImpl<MCFixup> &Fixups,
1451                     const MCSubtargetInfo &STI) const {
1452   // {12-9} = reg
1453   // {8}    = (U)nsigned (add == '1', sub == '0')
1454   // {7-0}  = imm8
1455   unsigned Reg, Imm8;
1456   bool isAdd;
1457   // If The first operand isn't a register, we have a label reference.
1458   const MCOperand &MO = MI.getOperand(OpIdx);
1459   if (!MO.isReg()) {
1460     Reg = CTX.getRegisterInfo()->getEncodingValue(ARM::PC);   // Rn is PC.
1461     Imm8 = 0;
1462     isAdd = false; // 'U' bit is handled as part of the fixup.
1463 
1464     assert(MO.isExpr() && "Unexpected machine operand type!");
1465     const MCExpr *Expr = MO.getExpr();
1466     MCFixupKind Kind;
1467     if (isThumb2(STI))
1468       Kind = MCFixupKind(ARM::fixup_t2_pcrel_10);
1469     else
1470       Kind = MCFixupKind(ARM::fixup_arm_pcrel_10);
1471     Fixups.push_back(MCFixup::create(0, Expr, Kind, MI.getLoc()));
1472 
1473     ++MCNumCPRelocations;
1474   } else {
1475     EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm8, Fixups, STI);
1476     isAdd = ARM_AM::getAM5Op(Imm8) == ARM_AM::add;
1477   }
1478 
1479   uint32_t Binary = ARM_AM::getAM5Offset(Imm8);
1480   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1481   if (isAdd)
1482     Binary |= (1 << 8);
1483   Binary |= (Reg << 9);
1484   return Binary;
1485 }
1486 
1487 /// getAddrMode5FP16OpValue - Return encoding info for 'reg +/- (imm8 << 1)' operand.
1488 uint32_t ARMMCCodeEmitter::
1489 getAddrMode5FP16OpValue(const MCInst &MI, unsigned OpIdx,
1490                     SmallVectorImpl<MCFixup> &Fixups,
1491                     const MCSubtargetInfo &STI) const {
1492   // {12-9} = reg
1493   // {8}    = (U)nsigned (add == '1', sub == '0')
1494   // {7-0}  = imm8
1495   unsigned Reg, Imm8;
1496   bool isAdd;
1497   // If The first operand isn't a register, we have a label reference.
1498   const MCOperand &MO = MI.getOperand(OpIdx);
1499   if (!MO.isReg()) {
1500     Reg = CTX.getRegisterInfo()->getEncodingValue(ARM::PC);   // Rn is PC.
1501     Imm8 = 0;
1502     isAdd = false; // 'U' bit is handled as part of the fixup.
1503 
1504     assert(MO.isExpr() && "Unexpected machine operand type!");
1505     const MCExpr *Expr = MO.getExpr();
1506     MCFixupKind Kind;
1507     if (isThumb2(STI))
1508       Kind = MCFixupKind(ARM::fixup_t2_pcrel_9);
1509     else
1510       Kind = MCFixupKind(ARM::fixup_arm_pcrel_9);
1511     Fixups.push_back(MCFixup::create(0, Expr, Kind, MI.getLoc()));
1512 
1513     ++MCNumCPRelocations;
1514   } else {
1515     EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm8, Fixups, STI);
1516     isAdd = ARM_AM::getAM5Op(Imm8) == ARM_AM::add;
1517   }
1518 
1519   uint32_t Binary = ARM_AM::getAM5Offset(Imm8);
1520   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1521   if (isAdd)
1522     Binary |= (1 << 8);
1523   Binary |= (Reg << 9);
1524   return Binary;
1525 }
1526 
1527 unsigned ARMMCCodeEmitter::
1528 getSORegRegOpValue(const MCInst &MI, unsigned OpIdx,
1529                 SmallVectorImpl<MCFixup> &Fixups,
1530                 const MCSubtargetInfo &STI) const {
1531   // Sub-operands are [reg, reg, imm]. The first register is Rm, the reg to be
1532   // shifted. The second is Rs, the amount to shift by, and the third specifies
1533   // the type of the shift.
1534   //
1535   // {3-0} = Rm.
1536   // {4}   = 1
1537   // {6-5} = type
1538   // {11-8} = Rs
1539   // {7}    = 0
1540 
1541   const MCOperand &MO  = MI.getOperand(OpIdx);
1542   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1543   const MCOperand &MO2 = MI.getOperand(OpIdx + 2);
1544   ARM_AM::ShiftOpc SOpc = ARM_AM::getSORegShOp(MO2.getImm());
1545 
1546   // Encode Rm.
1547   unsigned Binary = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1548 
1549   // Encode the shift opcode.
1550   unsigned SBits = 0;
1551   unsigned Rs = MO1.getReg();
1552   if (Rs) {
1553     // Set shift operand (bit[7:4]).
1554     // LSL - 0001
1555     // LSR - 0011
1556     // ASR - 0101
1557     // ROR - 0111
1558     switch (SOpc) {
1559     default: llvm_unreachable("Unknown shift opc!");
1560     case ARM_AM::lsl: SBits = 0x1; break;
1561     case ARM_AM::lsr: SBits = 0x3; break;
1562     case ARM_AM::asr: SBits = 0x5; break;
1563     case ARM_AM::ror: SBits = 0x7; break;
1564     }
1565   }
1566 
1567   Binary |= SBits << 4;
1568 
1569   // Encode the shift operation Rs.
1570   // Encode Rs bit[11:8].
1571   assert(ARM_AM::getSORegOffset(MO2.getImm()) == 0);
1572   return Binary | (CTX.getRegisterInfo()->getEncodingValue(Rs) << ARMII::RegRsShift);
1573 }
1574 
1575 unsigned ARMMCCodeEmitter::
1576 getSORegImmOpValue(const MCInst &MI, unsigned OpIdx,
1577                 SmallVectorImpl<MCFixup> &Fixups,
1578                 const MCSubtargetInfo &STI) const {
1579   // Sub-operands are [reg, imm]. The first register is Rm, the reg to be
1580   // shifted. The second is the amount to shift by.
1581   //
1582   // {3-0} = Rm.
1583   // {4}   = 0
1584   // {6-5} = type
1585   // {11-7} = imm
1586 
1587   const MCOperand &MO  = MI.getOperand(OpIdx);
1588   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1589   ARM_AM::ShiftOpc SOpc = ARM_AM::getSORegShOp(MO1.getImm());
1590 
1591   // Encode Rm.
1592   unsigned Binary = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1593 
1594   // Encode the shift opcode.
1595   unsigned SBits = 0;
1596 
1597   // Set shift operand (bit[6:4]).
1598   // LSL - 000
1599   // LSR - 010
1600   // ASR - 100
1601   // ROR - 110
1602   // RRX - 110 and bit[11:8] clear.
1603   switch (SOpc) {
1604   default: llvm_unreachable("Unknown shift opc!");
1605   case ARM_AM::lsl: SBits = 0x0; break;
1606   case ARM_AM::lsr: SBits = 0x2; break;
1607   case ARM_AM::asr: SBits = 0x4; break;
1608   case ARM_AM::ror: SBits = 0x6; break;
1609   case ARM_AM::rrx:
1610     Binary |= 0x60;
1611     return Binary;
1612   }
1613 
1614   // Encode shift_imm bit[11:7].
1615   Binary |= SBits << 4;
1616   unsigned Offset = ARM_AM::getSORegOffset(MO1.getImm());
1617   assert(Offset < 32 && "Offset must be in range 0-31!");
1618   return Binary | (Offset << 7);
1619 }
1620 
1621 
1622 unsigned ARMMCCodeEmitter::
1623 getT2AddrModeSORegOpValue(const MCInst &MI, unsigned OpNum,
1624                 SmallVectorImpl<MCFixup> &Fixups,
1625                 const MCSubtargetInfo &STI) const {
1626   const MCOperand &MO1 = MI.getOperand(OpNum);
1627   const MCOperand &MO2 = MI.getOperand(OpNum+1);
1628   const MCOperand &MO3 = MI.getOperand(OpNum+2);
1629 
1630   // Encoded as [Rn, Rm, imm].
1631   // FIXME: Needs fixup support.
1632   unsigned Value = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
1633   Value <<= 4;
1634   Value |= CTX.getRegisterInfo()->getEncodingValue(MO2.getReg());
1635   Value <<= 2;
1636   Value |= MO3.getImm();
1637 
1638   return Value;
1639 }
1640 
1641 template<unsigned Bits, unsigned Shift>
1642 unsigned ARMMCCodeEmitter::
1643 getT2AddrModeImmOpValue(const MCInst &MI, unsigned OpNum,
1644                         SmallVectorImpl<MCFixup> &Fixups,
1645                         const MCSubtargetInfo &STI) const {
1646   const MCOperand &MO1 = MI.getOperand(OpNum);
1647   const MCOperand &MO2 = MI.getOperand(OpNum+1);
1648 
1649   // FIXME: Needs fixup support.
1650   unsigned Value = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
1651 
1652   // If the immediate is B bits long, we need B+1 bits in order
1653   // to represent the (inverse of the) sign bit.
1654   Value <<= (Bits + 1);
1655   int32_t tmp = (int32_t)MO2.getImm();
1656   if (tmp == INT32_MIN) { // represents subtracting zero rather than adding it
1657     tmp = 0;
1658   } else if (tmp < 0) {
1659     tmp = abs(tmp);
1660   } else {
1661     Value |= (1U << Bits); // Set the ADD bit
1662   }
1663   Value |= (tmp >> Shift) & ((1U << Bits) - 1);
1664   return Value;
1665 }
1666 
1667 unsigned ARMMCCodeEmitter::
1668 getT2AddrModeImm8OffsetOpValue(const MCInst &MI, unsigned OpNum,
1669                          SmallVectorImpl<MCFixup> &Fixups,
1670                          const MCSubtargetInfo &STI) const {
1671   const MCOperand &MO1 = MI.getOperand(OpNum);
1672 
1673   // FIXME: Needs fixup support.
1674   unsigned Value = 0;
1675   auto tmp = static_cast<uint32_t>(MO1.getImm());
1676   if (static_cast<int32_t>(tmp) < 0)
1677     tmp = -tmp;
1678   else
1679     Value |= 256; // Set the ADD bit
1680   Value |= tmp & 255;
1681   return Value;
1682 }
1683 
1684 unsigned ARMMCCodeEmitter::
1685 getT2SORegOpValue(const MCInst &MI, unsigned OpIdx,
1686                 SmallVectorImpl<MCFixup> &Fixups,
1687                 const MCSubtargetInfo &STI) const {
1688   // Sub-operands are [reg, imm]. The first register is Rm, the reg to be
1689   // shifted. The second is the amount to shift by.
1690   //
1691   // {3-0} = Rm.
1692   // {4}   = 0
1693   // {6-5} = type
1694   // {11-7} = imm
1695 
1696   const MCOperand &MO  = MI.getOperand(OpIdx);
1697   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1698   ARM_AM::ShiftOpc SOpc = ARM_AM::getSORegShOp(MO1.getImm());
1699 
1700   // Encode Rm.
1701   unsigned Binary = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1702 
1703   // Encode the shift opcode.
1704   unsigned SBits = 0;
1705   // Set shift operand (bit[6:4]).
1706   // LSL - 000
1707   // LSR - 010
1708   // ASR - 100
1709   // ROR - 110
1710   switch (SOpc) {
1711   default: llvm_unreachable("Unknown shift opc!");
1712   case ARM_AM::lsl: SBits = 0x0; break;
1713   case ARM_AM::lsr: SBits = 0x2; break;
1714   case ARM_AM::asr: SBits = 0x4; break;
1715   case ARM_AM::rrx: [[fallthrough]];
1716   case ARM_AM::ror: SBits = 0x6; break;
1717   }
1718 
1719   Binary |= SBits << 4;
1720   if (SOpc == ARM_AM::rrx)
1721     return Binary;
1722 
1723   // Encode shift_imm bit[11:7].
1724   return Binary | ARM_AM::getSORegOffset(MO1.getImm()) << 7;
1725 }
1726 
1727 unsigned ARMMCCodeEmitter::
1728 getBitfieldInvertedMaskOpValue(const MCInst &MI, unsigned Op,
1729                                SmallVectorImpl<MCFixup> &Fixups,
1730                                const MCSubtargetInfo &STI) const {
1731   // 10 bits. lower 5 bits are the lsb of the mask, high five bits are the
1732   // msb of the mask.
1733   const MCOperand &MO = MI.getOperand(Op);
1734   uint32_t v = ~MO.getImm();
1735   uint32_t lsb = llvm::countr_zero(v);
1736   uint32_t msb = llvm::Log2_32(v);
1737   assert(v != 0 && lsb < 32 && msb < 32 && "Illegal bitfield mask!");
1738   return lsb | (msb << 5);
1739 }
1740 
1741 unsigned ARMMCCodeEmitter::
1742 getRegisterListOpValue(const MCInst &MI, unsigned Op,
1743                        SmallVectorImpl<MCFixup> &Fixups,
1744                        const MCSubtargetInfo &STI) const {
1745   // VLDM/VSTM/VSCCLRM:
1746   //   {12-8} = Vd
1747   //   {7-0}  = Number of registers
1748   //
1749   // LDM/STM:
1750   //   {15-0}  = Bitfield of GPRs.
1751   unsigned Reg = MI.getOperand(Op).getReg();
1752   bool SPRRegs = ARMMCRegisterClasses[ARM::SPRRegClassID].contains(Reg);
1753   bool DPRRegs = ARMMCRegisterClasses[ARM::DPRRegClassID].contains(Reg);
1754 
1755   unsigned Binary = 0;
1756 
1757   if (SPRRegs || DPRRegs) {
1758     // VLDM/VSTM/VSCCLRM
1759     unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(Reg);
1760     unsigned NumRegs = (MI.getNumOperands() - Op) & 0xff;
1761     Binary |= (RegNo & 0x1f) << 8;
1762 
1763     // Ignore VPR
1764     if (MI.getOpcode() == ARM::VSCCLRMD || MI.getOpcode() == ARM::VSCCLRMS)
1765       --NumRegs;
1766     if (SPRRegs)
1767       Binary |= NumRegs;
1768     else
1769       Binary |= NumRegs * 2;
1770   } else {
1771     const MCRegisterInfo &MRI = *CTX.getRegisterInfo();
1772     assert(is_sorted(drop_begin(MI, Op),
1773                      [&](const MCOperand &LHS, const MCOperand &RHS) {
1774                        return MRI.getEncodingValue(LHS.getReg()) <
1775                               MRI.getEncodingValue(RHS.getReg());
1776                      }));
1777     for (unsigned I = Op, E = MI.getNumOperands(); I < E; ++I) {
1778       unsigned RegNo = MRI.getEncodingValue(MI.getOperand(I).getReg());
1779       Binary |= 1 << RegNo;
1780     }
1781   }
1782 
1783   return Binary;
1784 }
1785 
1786 /// getAddrMode6AddressOpValue - Encode an addrmode6 register number along
1787 /// with the alignment operand.
1788 unsigned ARMMCCodeEmitter::
1789 getAddrMode6AddressOpValue(const MCInst &MI, unsigned Op,
1790                            SmallVectorImpl<MCFixup> &Fixups,
1791                            const MCSubtargetInfo &STI) const {
1792   const MCOperand &Reg = MI.getOperand(Op);
1793   const MCOperand &Imm = MI.getOperand(Op + 1);
1794 
1795   unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(Reg.getReg());
1796   unsigned Align = 0;
1797 
1798   switch (Imm.getImm()) {
1799   default: break;
1800   case 2:
1801   case 4:
1802   case 8:  Align = 0x01; break;
1803   case 16: Align = 0x02; break;
1804   case 32: Align = 0x03; break;
1805   }
1806 
1807   return RegNo | (Align << 4);
1808 }
1809 
1810 /// getAddrMode6OneLane32AddressOpValue - Encode an addrmode6 register number
1811 /// along  with the alignment operand for use in VST1 and VLD1 with size 32.
1812 unsigned ARMMCCodeEmitter::
1813 getAddrMode6OneLane32AddressOpValue(const MCInst &MI, unsigned Op,
1814                                     SmallVectorImpl<MCFixup> &Fixups,
1815                                     const MCSubtargetInfo &STI) const {
1816   const MCOperand &Reg = MI.getOperand(Op);
1817   const MCOperand &Imm = MI.getOperand(Op + 1);
1818 
1819   unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(Reg.getReg());
1820   unsigned Align = 0;
1821 
1822   switch (Imm.getImm()) {
1823   default: break;
1824   case 8:
1825   case 16:
1826   case 32: // Default '0' value for invalid alignments of 8, 16, 32 bytes.
1827   case 2: Align = 0x00; break;
1828   case 4: Align = 0x03; break;
1829   }
1830 
1831   return RegNo | (Align << 4);
1832 }
1833 
1834 
1835 /// getAddrMode6DupAddressOpValue - Encode an addrmode6 register number and
1836 /// alignment operand for use in VLD-dup instructions.  This is the same as
1837 /// getAddrMode6AddressOpValue except for the alignment encoding, which is
1838 /// different for VLD4-dup.
1839 unsigned ARMMCCodeEmitter::
1840 getAddrMode6DupAddressOpValue(const MCInst &MI, unsigned Op,
1841                               SmallVectorImpl<MCFixup> &Fixups,
1842                               const MCSubtargetInfo &STI) const {
1843   const MCOperand &Reg = MI.getOperand(Op);
1844   const MCOperand &Imm = MI.getOperand(Op + 1);
1845 
1846   unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(Reg.getReg());
1847   unsigned Align = 0;
1848 
1849   switch (Imm.getImm()) {
1850   default: break;
1851   case 2:
1852   case 4:
1853   case 8:  Align = 0x01; break;
1854   case 16: Align = 0x03; break;
1855   }
1856 
1857   return RegNo | (Align << 4);
1858 }
1859 
1860 unsigned ARMMCCodeEmitter::
1861 getAddrMode6OffsetOpValue(const MCInst &MI, unsigned Op,
1862                           SmallVectorImpl<MCFixup> &Fixups,
1863                           const MCSubtargetInfo &STI) const {
1864   const MCOperand &MO = MI.getOperand(Op);
1865   if (MO.getReg() == 0) return 0x0D;
1866   return CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1867 }
1868 
1869 unsigned ARMMCCodeEmitter::
1870 getShiftRight8Imm(const MCInst &MI, unsigned Op,
1871                   SmallVectorImpl<MCFixup> &Fixups,
1872                   const MCSubtargetInfo &STI) const {
1873   return 8 - MI.getOperand(Op).getImm();
1874 }
1875 
1876 unsigned ARMMCCodeEmitter::
1877 getShiftRight16Imm(const MCInst &MI, unsigned Op,
1878                    SmallVectorImpl<MCFixup> &Fixups,
1879                    const MCSubtargetInfo &STI) const {
1880   return 16 - MI.getOperand(Op).getImm();
1881 }
1882 
1883 unsigned ARMMCCodeEmitter::
1884 getShiftRight32Imm(const MCInst &MI, unsigned Op,
1885                    SmallVectorImpl<MCFixup> &Fixups,
1886                    const MCSubtargetInfo &STI) const {
1887   return 32 - MI.getOperand(Op).getImm();
1888 }
1889 
1890 unsigned ARMMCCodeEmitter::
1891 getShiftRight64Imm(const MCInst &MI, unsigned Op,
1892                    SmallVectorImpl<MCFixup> &Fixups,
1893                    const MCSubtargetInfo &STI) const {
1894   return 64 - MI.getOperand(Op).getImm();
1895 }
1896 
1897 void ARMMCCodeEmitter::
1898 encodeInstruction(const MCInst &MI, raw_ostream &OS,
1899                   SmallVectorImpl<MCFixup> &Fixups,
1900                   const MCSubtargetInfo &STI) const {
1901   // Pseudo instructions don't get encoded.
1902   const MCInstrDesc &Desc = MCII.get(MI.getOpcode());
1903   uint64_t TSFlags = Desc.TSFlags;
1904   if ((TSFlags & ARMII::FormMask) == ARMII::Pseudo)
1905     return;
1906 
1907   int Size;
1908   if (Desc.getSize() == 2 || Desc.getSize() == 4)
1909     Size = Desc.getSize();
1910   else
1911     llvm_unreachable("Unexpected instruction size!");
1912 
1913   uint32_t Binary = getBinaryCodeForInstr(MI, Fixups, STI);
1914   // Thumb 32-bit wide instructions need to emit the high order halfword
1915   // first.
1916   if (isThumb(STI) && Size == 4) {
1917     EmitConstant(Binary >> 16, 2, OS);
1918     EmitConstant(Binary & 0xffff, 2, OS);
1919   } else
1920     EmitConstant(Binary, Size, OS);
1921   ++MCNumEmitted;  // Keep track of the # of mi's emitted.
1922 }
1923 
1924 template <bool isNeg, ARM::Fixups fixup>
1925 uint32_t
1926 ARMMCCodeEmitter::getBFTargetOpValue(const MCInst &MI, unsigned OpIdx,
1927                                      SmallVectorImpl<MCFixup> &Fixups,
1928                                      const MCSubtargetInfo &STI) const {
1929   const MCOperand MO = MI.getOperand(OpIdx);
1930   if (MO.isExpr())
1931     return ::getBranchTargetOpValue(MI, OpIdx, fixup, Fixups, STI);
1932   return isNeg ? -(MO.getImm() >> 1) : (MO.getImm() >> 1);
1933 }
1934 
1935 uint32_t
1936 ARMMCCodeEmitter::getBFAfterTargetOpValue(const MCInst &MI, unsigned OpIdx,
1937                                           SmallVectorImpl<MCFixup> &Fixups,
1938                                           const MCSubtargetInfo &STI) const {
1939   const MCOperand MO = MI.getOperand(OpIdx);
1940   const MCOperand BranchMO = MI.getOperand(0);
1941 
1942   if (MO.isExpr()) {
1943     assert(BranchMO.isExpr());
1944     const MCExpr *DiffExpr = MCBinaryExpr::createSub(
1945         MO.getExpr(), BranchMO.getExpr(), CTX);
1946     MCFixupKind Kind = MCFixupKind(ARM::fixup_bfcsel_else_target);
1947     Fixups.push_back(llvm::MCFixup::create(0, DiffExpr, Kind, MI.getLoc()));
1948     return 0;
1949   }
1950 
1951   assert(MO.isImm() && BranchMO.isImm());
1952   int Diff = MO.getImm() - BranchMO.getImm();
1953   assert(Diff == 4 || Diff == 2);
1954 
1955   return Diff == 4;
1956 }
1957 
1958 uint32_t ARMMCCodeEmitter::getVPTMaskOpValue(const MCInst &MI, unsigned OpIdx,
1959                                              SmallVectorImpl<MCFixup> &Fixups,
1960                                              const MCSubtargetInfo &STI)const {
1961   const MCOperand MO = MI.getOperand(OpIdx);
1962   assert(MO.isImm() && "Unexpected operand type!");
1963 
1964   int Value = MO.getImm();
1965   int Imm = 0;
1966 
1967   // VPT Masks are actually encoded as a series of invert/don't invert bits,
1968   // rather than true/false bits.
1969   unsigned PrevBit = 0;
1970   for (int i = 3; i >= 0; --i) {
1971     unsigned Bit = (Value >> i) & 1;
1972 
1973     // Check if we are at the end of the mask.
1974     if ((Value & ~(~0U << i)) == 0) {
1975       Imm |= (1 << i);
1976       break;
1977     }
1978 
1979     // Convert the bit in the mask based on the previous bit.
1980     if (Bit != PrevBit)
1981       Imm |= (1 << i);
1982 
1983     PrevBit = Bit;
1984   }
1985 
1986   return Imm;
1987 }
1988 
1989 uint32_t ARMMCCodeEmitter::getRestrictedCondCodeOpValue(
1990     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
1991     const MCSubtargetInfo &STI) const {
1992 
1993   const MCOperand MO = MI.getOperand(OpIdx);
1994   assert(MO.isImm() && "Unexpected operand type!");
1995 
1996   switch (MO.getImm()) {
1997   default:
1998     assert(0 && "Unexpected Condition!");
1999     return 0;
2000   case ARMCC::HS:
2001   case ARMCC::EQ:
2002     return 0;
2003   case ARMCC::HI:
2004   case ARMCC::NE:
2005     return 1;
2006   case ARMCC::GE:
2007     return 4;
2008   case ARMCC::LT:
2009     return 5;
2010   case ARMCC::GT:
2011     return 6;
2012   case ARMCC::LE:
2013     return 7;
2014   }
2015 }
2016 
2017 uint32_t ARMMCCodeEmitter::
2018 getPowerTwoOpValue(const MCInst &MI, unsigned OpIdx,
2019                    SmallVectorImpl<MCFixup> &Fixups,
2020                    const MCSubtargetInfo &STI) const {
2021   const MCOperand &MO = MI.getOperand(OpIdx);
2022   assert(MO.isImm() && "Unexpected operand type!");
2023   return llvm::countr_zero((uint64_t)MO.getImm());
2024 }
2025 
2026 template <unsigned start>
2027 uint32_t ARMMCCodeEmitter::
2028 getMVEPairVectorIndexOpValue(const MCInst &MI, unsigned OpIdx,
2029                              SmallVectorImpl<MCFixup> &Fixups,
2030                              const MCSubtargetInfo &STI) const {
2031   const MCOperand MO = MI.getOperand(OpIdx);
2032   assert(MO.isImm() && "Unexpected operand type!");
2033 
2034   int Value = MO.getImm();
2035   return Value - start;
2036 }
2037 
2038 #include "ARMGenMCCodeEmitter.inc"
2039 
2040 MCCodeEmitter *llvm::createARMLEMCCodeEmitter(const MCInstrInfo &MCII,
2041                                               MCContext &Ctx) {
2042   return new ARMMCCodeEmitter(MCII, Ctx, true);
2043 }
2044 
2045 MCCodeEmitter *llvm::createARMBEMCCodeEmitter(const MCInstrInfo &MCII,
2046                                               MCContext &Ctx) {
2047   return new ARMMCCodeEmitter(MCII, Ctx, false);
2048 }
2049