xref: /freebsd/contrib/llvm-project/llvm/lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp (revision 2c2ec6bbc9cc7762a250ffe903bda6c2e44d25ff)
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/ARMMCAsmInfo.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/EndianStream.h"
33 #include "llvm/Support/ErrorHandling.h"
34 #include "llvm/Support/MathExtras.h"
35 #include "llvm/TargetParser/Triple.h"
36 #include <cassert>
37 #include <cstdint>
38 #include <cstdlib>
39 
40 using namespace llvm;
41 
42 #define DEBUG_TYPE "mccodeemitter"
43 
44 STATISTIC(MCNumEmitted, "Number of MC instructions emitted.");
45 STATISTIC(MCNumCPRelocations, "Number of constant pool relocations created.");
46 
47 namespace {
48 
49 class ARMMCCodeEmitter : public MCCodeEmitter {
50   const MCInstrInfo &MCII;
51   MCContext &CTX;
52   bool IsLittleEndian;
53 
54 public:
55   ARMMCCodeEmitter(const MCInstrInfo &mcii, MCContext &ctx, bool IsLittle)
56     : MCII(mcii), CTX(ctx), IsLittleEndian(IsLittle) {
57   }
58   ARMMCCodeEmitter(const ARMMCCodeEmitter &) = delete;
59   ARMMCCodeEmitter &operator=(const ARMMCCodeEmitter &) = delete;
60   ~ARMMCCodeEmitter() override = default;
61 
62   bool isThumb(const MCSubtargetInfo &STI) const {
63     return STI.hasFeature(ARM::ModeThumb);
64   }
65 
66   bool isThumb2(const MCSubtargetInfo &STI) const {
67     return isThumb(STI) && STI.hasFeature(ARM::FeatureThumb2);
68   }
69 
70   bool isTargetMachO(const MCSubtargetInfo &STI) const {
71     const Triple &TT = STI.getTargetTriple();
72     return TT.isOSBinFormatMachO();
73   }
74 
75   unsigned getMachineSoImmOpValue(unsigned SoImm) const;
76 
77   // getBinaryCodeForInstr - TableGen'erated function for getting the
78   // binary encoding for an instruction.
79   uint64_t getBinaryCodeForInstr(const MCInst &MI,
80                                  SmallVectorImpl<MCFixup> &Fixups,
81                                  const MCSubtargetInfo &STI) const;
82 
83   /// getMachineOpValue - Return binary encoding of operand. If the machine
84   /// operand requires relocation, record the relocation and return zero.
85   unsigned getMachineOpValue(const MCInst &MI,const MCOperand &MO,
86                              SmallVectorImpl<MCFixup> &Fixups,
87                              const MCSubtargetInfo &STI) const;
88 
89   /// getHiLoImmOpValue - Return the encoding for either the hi / low 16-bit, or
90   /// high/middle-high/middle-low/low 8 bits of the specified operand. This is
91   /// used for operands with :lower16:, :upper16: :lower0_7:, :lower8_15:,
92   /// :higher0_7:, and :higher8_15: prefixes.
93   uint32_t getHiLoImmOpValue(const MCInst &MI, unsigned OpIdx,
94                              SmallVectorImpl<MCFixup> &Fixups,
95                              const MCSubtargetInfo &STI) const;
96 
97   bool EncodeAddrModeOpValues(const MCInst &MI, unsigned OpIdx,
98                               unsigned &Reg, unsigned &Imm,
99                               SmallVectorImpl<MCFixup> &Fixups,
100                               const MCSubtargetInfo &STI) const;
101 
102   /// getThumbBLTargetOpValue - Return encoding info for Thumb immediate
103   /// BL branch target.
104   uint32_t getThumbBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
105                                    SmallVectorImpl<MCFixup> &Fixups,
106                                    const MCSubtargetInfo &STI) const;
107 
108   /// getThumbBLXTargetOpValue - Return encoding info for Thumb immediate
109   /// BLX branch target.
110   uint32_t getThumbBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
111                                     SmallVectorImpl<MCFixup> &Fixups,
112                                     const MCSubtargetInfo &STI) const;
113 
114   /// getThumbBRTargetOpValue - Return encoding info for Thumb branch target.
115   uint32_t getThumbBRTargetOpValue(const MCInst &MI, unsigned OpIdx,
116                                    SmallVectorImpl<MCFixup> &Fixups,
117                                    const MCSubtargetInfo &STI) const;
118 
119   /// getThumbBCCTargetOpValue - Return encoding info for Thumb branch target.
120   uint32_t getThumbBCCTargetOpValue(const MCInst &MI, unsigned OpIdx,
121                                     SmallVectorImpl<MCFixup> &Fixups,
122                                     const MCSubtargetInfo &STI) const;
123 
124   /// getThumbCBTargetOpValue - Return encoding info for Thumb branch target.
125   uint32_t getThumbCBTargetOpValue(const MCInst &MI, unsigned OpIdx,
126                                    SmallVectorImpl<MCFixup> &Fixups,
127                                    const MCSubtargetInfo &STI) const;
128 
129   /// getBranchTargetOpValue - Return encoding info for 24-bit immediate
130   /// branch target.
131   uint32_t getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
132                                   SmallVectorImpl<MCFixup> &Fixups,
133                                   const MCSubtargetInfo &STI) const;
134 
135   /// getThumbBranchTargetOpValue - Return encoding info for 24-bit
136   /// immediate Thumb2 direct branch target.
137   uint32_t getThumbBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
138                                        SmallVectorImpl<MCFixup> &Fixups,
139                                        const MCSubtargetInfo &STI) const;
140 
141   /// getARMBranchTargetOpValue - Return encoding info for 24-bit immediate
142   /// branch target.
143   uint32_t getARMBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
144                                      SmallVectorImpl<MCFixup> &Fixups,
145                                      const MCSubtargetInfo &STI) const;
146   uint32_t getARMBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
147                                  SmallVectorImpl<MCFixup> &Fixups,
148                                  const MCSubtargetInfo &STI) const;
149   uint32_t getARMBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
150                                   SmallVectorImpl<MCFixup> &Fixups,
151                                   const MCSubtargetInfo &STI) const;
152 
153   /// getAdrLabelOpValue - Return encoding info for 12-bit immediate
154   /// ADR label target.
155   uint32_t getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
156                               SmallVectorImpl<MCFixup> &Fixups,
157                               const MCSubtargetInfo &STI) const;
158   uint32_t getThumbAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
159                               SmallVectorImpl<MCFixup> &Fixups,
160                               const MCSubtargetInfo &STI) const;
161   uint32_t getT2AdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
162                               SmallVectorImpl<MCFixup> &Fixups,
163                               const MCSubtargetInfo &STI) const;
164 
165   uint32_t getITMaskOpValue(const MCInst &MI, unsigned OpIdx,
166                             SmallVectorImpl<MCFixup> &Fixups,
167                             const MCSubtargetInfo &STI) const;
168 
169   /// getMVEShiftImmOpValue - Return encoding info for the 'sz:imm5'
170   /// operand.
171   uint32_t getMVEShiftImmOpValue(const MCInst &MI, unsigned OpIdx,
172                                  SmallVectorImpl<MCFixup> &Fixups,
173                                  const MCSubtargetInfo &STI) const;
174 
175   /// getAddrModeImm12OpValue - Return encoding info for 'reg +/- imm12'
176   /// operand.
177   uint32_t getAddrModeImm12OpValue(const MCInst &MI, unsigned OpIdx,
178                                    SmallVectorImpl<MCFixup> &Fixups,
179                                    const MCSubtargetInfo &STI) const;
180 
181   /// getThumbAddrModeRegRegOpValue - Return encoding for 'reg + reg' operand.
182   uint32_t getThumbAddrModeRegRegOpValue(const MCInst &MI, unsigned OpIdx,
183                                          SmallVectorImpl<MCFixup> &Fixups,
184                                          const MCSubtargetInfo &STI) const;
185 
186   /// getT2AddrModeImm8s4OpValue - Return encoding info for 'reg +/- imm8<<2'
187   /// operand.
188   uint32_t getT2AddrModeImm8s4OpValue(const MCInst &MI, unsigned OpIdx,
189                                    SmallVectorImpl<MCFixup> &Fixups,
190                                    const MCSubtargetInfo &STI) const;
191 
192   /// getT2AddrModeImm7s4OpValue - Return encoding info for 'reg +/- imm7<<2'
193   /// operand.
194   uint32_t getT2AddrModeImm7s4OpValue(const MCInst &MI, unsigned OpIdx,
195                                       SmallVectorImpl<MCFixup> &Fixups,
196                                       const MCSubtargetInfo &STI) const;
197 
198   /// getT2AddrModeImm0_1020s4OpValue - Return encoding info for 'reg + imm8<<2'
199   /// operand.
200   uint32_t getT2AddrModeImm0_1020s4OpValue(const MCInst &MI, unsigned OpIdx,
201                                    SmallVectorImpl<MCFixup> &Fixups,
202                                    const MCSubtargetInfo &STI) const;
203 
204   /// getT2ScaledImmOpValue - Return encoding info for '+/- immX<<Y'
205   /// operand.
206   template<unsigned Bits, unsigned Shift>
207   uint32_t getT2ScaledImmOpValue(const MCInst &MI, unsigned OpIdx,
208                                  SmallVectorImpl<MCFixup> &Fixups,
209                                  const MCSubtargetInfo &STI) const;
210 
211   /// getMveAddrModeRQOpValue - Return encoding info for 'reg, vreg'
212   /// operand.
213   uint32_t getMveAddrModeRQOpValue(const MCInst &MI, unsigned OpIdx,
214                                    SmallVectorImpl<MCFixup> &Fixups,
215                                    const MCSubtargetInfo &STI) const;
216 
217   /// getMveAddrModeQOpValue - Return encoding info for 'reg +/- imm7<<{shift}'
218   /// operand.
219   template<int shift>
220   uint32_t getMveAddrModeQOpValue(const MCInst &MI, unsigned OpIdx,
221                                   SmallVectorImpl<MCFixup> &Fixups,
222                                   const MCSubtargetInfo &STI) const;
223 
224   /// getLdStSORegOpValue - Return encoding info for 'reg +/- reg shop imm'
225   /// operand as needed by load/store instructions.
226   uint32_t getLdStSORegOpValue(const MCInst &MI, unsigned OpIdx,
227                                SmallVectorImpl<MCFixup> &Fixups,
228                                const MCSubtargetInfo &STI) const;
229 
230   /// getLdStmModeOpValue - Return encoding for load/store multiple mode.
231   uint32_t getLdStmModeOpValue(const MCInst &MI, unsigned OpIdx,
232                                SmallVectorImpl<MCFixup> &Fixups,
233                                const MCSubtargetInfo &STI) const {
234     ARM_AM::AMSubMode Mode = (ARM_AM::AMSubMode)MI.getOperand(OpIdx).getImm();
235     switch (Mode) {
236     default: llvm_unreachable("Unknown addressing sub-mode!");
237     case ARM_AM::da: return 0;
238     case ARM_AM::ia: return 1;
239     case ARM_AM::db: return 2;
240     case ARM_AM::ib: return 3;
241     }
242   }
243 
244   /// getShiftOp - Return the shift opcode (bit[6:5]) of the immediate value.
245   ///
246   unsigned getShiftOp(ARM_AM::ShiftOpc ShOpc) const {
247     switch (ShOpc) {
248     case ARM_AM::no_shift:
249     case ARM_AM::lsl: return 0;
250     case ARM_AM::lsr: return 1;
251     case ARM_AM::asr: return 2;
252     case ARM_AM::ror:
253     case ARM_AM::rrx: return 3;
254     default:
255       llvm_unreachable("Invalid ShiftOpc!");
256     }
257   }
258 
259   /// getAddrMode2OffsetOpValue - Return encoding for am2offset operands.
260   uint32_t getAddrMode2OffsetOpValue(const MCInst &MI, unsigned OpIdx,
261                                      SmallVectorImpl<MCFixup> &Fixups,
262                                      const MCSubtargetInfo &STI) const;
263 
264   /// getPostIdxRegOpValue - Return encoding for postidx_reg operands.
265   uint32_t getPostIdxRegOpValue(const MCInst &MI, unsigned OpIdx,
266                                 SmallVectorImpl<MCFixup> &Fixups,
267                                 const MCSubtargetInfo &STI) const;
268 
269   /// getAddrMode3OffsetOpValue - Return encoding for am3offset operands.
270   uint32_t getAddrMode3OffsetOpValue(const MCInst &MI, unsigned OpIdx,
271                                      SmallVectorImpl<MCFixup> &Fixups,
272                                      const MCSubtargetInfo &STI) const;
273 
274   /// getAddrMode3OpValue - Return encoding for addrmode3 operands.
275   uint32_t getAddrMode3OpValue(const MCInst &MI, unsigned OpIdx,
276                                SmallVectorImpl<MCFixup> &Fixups,
277                                const MCSubtargetInfo &STI) const;
278 
279   /// getAddrModeThumbSPOpValue - Return encoding info for 'reg +/- imm12'
280   /// operand.
281   uint32_t getAddrModeThumbSPOpValue(const MCInst &MI, unsigned OpIdx,
282                                      SmallVectorImpl<MCFixup> &Fixups,
283                                      const MCSubtargetInfo &STI) const;
284 
285   /// getAddrModeISOpValue - Encode the t_addrmode_is# operands.
286   uint32_t getAddrModeISOpValue(const MCInst &MI, unsigned OpIdx,
287                                 SmallVectorImpl<MCFixup> &Fixups,
288                                 const MCSubtargetInfo &STI) const;
289 
290   /// getAddrModePCOpValue - Return encoding for t_addrmode_pc operands.
291   uint32_t getAddrModePCOpValue(const MCInst &MI, unsigned OpIdx,
292                                 SmallVectorImpl<MCFixup> &Fixups,
293                                 const MCSubtargetInfo &STI) const;
294 
295   /// getAddrMode5OpValue - Return encoding info for 'reg +/- (imm8 << 2)' operand.
296   uint32_t getAddrMode5OpValue(const MCInst &MI, unsigned OpIdx,
297                                SmallVectorImpl<MCFixup> &Fixups,
298                                const MCSubtargetInfo &STI) const;
299 
300   /// getAddrMode5FP16OpValue - Return encoding info for 'reg +/- (imm8 << 1)' operand.
301   uint32_t getAddrMode5FP16OpValue(const MCInst &MI, unsigned OpIdx,
302                                SmallVectorImpl<MCFixup> &Fixups,
303                                const MCSubtargetInfo &STI) const;
304 
305   /// getCCOutOpValue - Return encoding of the 's' bit.
306   unsigned getCCOutOpValue(const MCInst &MI, unsigned Op,
307                            SmallVectorImpl<MCFixup> &Fixups,
308                            const MCSubtargetInfo &STI) const {
309     // The operand is either reg0 or CPSR. The 's' bit is encoded as '0' or
310     // '1' respectively.
311     return MI.getOperand(Op).getReg() == ARM::CPSR;
312   }
313 
314   unsigned getModImmOpValue(const MCInst &MI, unsigned Op,
315                             SmallVectorImpl<MCFixup> &Fixups,
316                             const MCSubtargetInfo &ST) const;
317 
318   /// getT2SOImmOpValue - Return an encoded 12-bit shifted-immediate value.
319   unsigned getT2SOImmOpValue(const MCInst &MI, unsigned Op,
320                              SmallVectorImpl<MCFixup> &Fixups,
321                              const MCSubtargetInfo &STI) const;
322 
323   unsigned getT2AddrModeSORegOpValue(const MCInst &MI, unsigned OpNum,
324     SmallVectorImpl<MCFixup> &Fixups,
325     const MCSubtargetInfo &STI) const;
326   template<unsigned Bits, unsigned Shift>
327   unsigned getT2AddrModeImmOpValue(const MCInst &MI, unsigned OpNum,
328     SmallVectorImpl<MCFixup> &Fixups,
329     const MCSubtargetInfo &STI) const;
330   unsigned getT2AddrModeImm8OffsetOpValue(const MCInst &MI, unsigned OpNum,
331     SmallVectorImpl<MCFixup> &Fixups,
332     const MCSubtargetInfo &STI) const;
333 
334   /// getSORegOpValue - Return an encoded so_reg shifted register value.
335   unsigned getSORegRegOpValue(const MCInst &MI, unsigned Op,
336                            SmallVectorImpl<MCFixup> &Fixups,
337                            const MCSubtargetInfo &STI) const;
338   unsigned getSORegImmOpValue(const MCInst &MI, unsigned Op,
339                            SmallVectorImpl<MCFixup> &Fixups,
340                            const MCSubtargetInfo &STI) const;
341   unsigned getT2SORegOpValue(const MCInst &MI, unsigned Op,
342                              SmallVectorImpl<MCFixup> &Fixups,
343                              const MCSubtargetInfo &STI) const;
344 
345   unsigned getNEONVcvtImm32OpValue(const MCInst &MI, unsigned Op,
346                                    SmallVectorImpl<MCFixup> &Fixups,
347                                    const MCSubtargetInfo &STI) const {
348     return 64 - MI.getOperand(Op).getImm();
349   }
350 
351   unsigned getBitfieldInvertedMaskOpValue(const MCInst &MI, unsigned Op,
352                                       SmallVectorImpl<MCFixup> &Fixups,
353                                       const MCSubtargetInfo &STI) const;
354 
355   unsigned getRegisterListOpValue(const MCInst &MI, unsigned Op,
356                                   SmallVectorImpl<MCFixup> &Fixups,
357                                   const MCSubtargetInfo &STI) const;
358   unsigned getAddrMode6AddressOpValue(const MCInst &MI, unsigned Op,
359                                       SmallVectorImpl<MCFixup> &Fixups,
360                                       const MCSubtargetInfo &STI) const;
361   unsigned getAddrMode6OneLane32AddressOpValue(const MCInst &MI, unsigned Op,
362                                         SmallVectorImpl<MCFixup> &Fixups,
363                                         const MCSubtargetInfo &STI) const;
364   unsigned getAddrMode6DupAddressOpValue(const MCInst &MI, unsigned Op,
365                                         SmallVectorImpl<MCFixup> &Fixups,
366                                         const MCSubtargetInfo &STI) const;
367   unsigned getAddrMode6OffsetOpValue(const MCInst &MI, unsigned Op,
368                                      SmallVectorImpl<MCFixup> &Fixups,
369                                      const MCSubtargetInfo &STI) const;
370 
371   unsigned getShiftRight8Imm(const MCInst &MI, unsigned Op,
372                              SmallVectorImpl<MCFixup> &Fixups,
373                              const MCSubtargetInfo &STI) const;
374   unsigned getShiftRight16Imm(const MCInst &MI, unsigned Op,
375                               SmallVectorImpl<MCFixup> &Fixups,
376                               const MCSubtargetInfo &STI) const;
377   unsigned getShiftRight32Imm(const MCInst &MI, unsigned Op,
378                               SmallVectorImpl<MCFixup> &Fixups,
379                               const MCSubtargetInfo &STI) const;
380   unsigned getShiftRight64Imm(const MCInst &MI, unsigned Op,
381                               SmallVectorImpl<MCFixup> &Fixups,
382                               const MCSubtargetInfo &STI) const;
383 
384   unsigned getThumbSRImmOpValue(const MCInst &MI, unsigned Op,
385                                  SmallVectorImpl<MCFixup> &Fixups,
386                                  const MCSubtargetInfo &STI) const;
387 
388   unsigned NEONThumb2DataIPostEncoder(const MCInst &MI,
389                                       unsigned EncodedValue,
390                                       const MCSubtargetInfo &STI) const;
391   unsigned NEONThumb2LoadStorePostEncoder(const MCInst &MI,
392                                           unsigned EncodedValue,
393                                           const MCSubtargetInfo &STI) const;
394   unsigned NEONThumb2DupPostEncoder(const MCInst &MI,
395                                     unsigned EncodedValue,
396                                     const MCSubtargetInfo &STI) const;
397   unsigned NEONThumb2V8PostEncoder(const MCInst &MI,
398                                    unsigned EncodedValue,
399                                    const MCSubtargetInfo &STI) const;
400 
401   unsigned VFPThumb2PostEncoder(const MCInst &MI,
402                                 unsigned EncodedValue,
403                                 const MCSubtargetInfo &STI) const;
404 
405   uint32_t getPowerTwoOpValue(const MCInst &MI, unsigned OpIdx,
406                               SmallVectorImpl<MCFixup> &Fixups,
407                               const MCSubtargetInfo &STI) const;
408 
409   void encodeInstruction(const MCInst &MI, SmallVectorImpl<char> &CB,
410                          SmallVectorImpl<MCFixup> &Fixups,
411                          const MCSubtargetInfo &STI) const override;
412 
413   template <bool isNeg, ARM::Fixups fixup>
414   uint32_t getBFTargetOpValue(const MCInst &MI, unsigned OpIdx,
415                               SmallVectorImpl<MCFixup> &Fixups,
416                               const MCSubtargetInfo &STI) const;
417 
418   uint32_t getBFAfterTargetOpValue(const MCInst &MI, unsigned OpIdx,
419                                    SmallVectorImpl<MCFixup> &Fixups,
420                                    const MCSubtargetInfo &STI) const;
421 
422   uint32_t getVPTMaskOpValue(const MCInst &MI, unsigned OpIdx,
423                              SmallVectorImpl<MCFixup> &Fixups,
424                              const MCSubtargetInfo &STI) const;
425   uint32_t getRestrictedCondCodeOpValue(const MCInst &MI, unsigned OpIdx,
426                                         SmallVectorImpl<MCFixup> &Fixups,
427                                         const MCSubtargetInfo &STI) const;
428   template <unsigned size>
429   uint32_t getMVEPairVectorIndexOpValue(const MCInst &MI, unsigned OpIdx,
430                                         SmallVectorImpl<MCFixup> &Fixups,
431                                         const MCSubtargetInfo &STI) const;
432 };
433 
434 } // end anonymous namespace
435 
436 static void addFixup(SmallVectorImpl<MCFixup> &Fixups, uint32_t Offset,
437                      const MCExpr *Value, uint16_t Kind) {
438   bool PCRel = false;
439   switch (Kind) {
440   case ARM::fixup_arm_ldst_pcrel_12:
441   case ARM::fixup_t2_ldst_pcrel_12:
442   case ARM::fixup_arm_pcrel_10_unscaled:
443   case ARM::fixup_arm_pcrel_10:
444   case ARM::fixup_t2_pcrel_10:
445   case ARM::fixup_arm_pcrel_9:
446   case ARM::fixup_t2_pcrel_9:
447   case ARM::fixup_thumb_adr_pcrel_10:
448   case ARM::fixup_arm_adr_pcrel_12:
449   case ARM::fixup_t2_adr_pcrel_12:
450   case ARM::fixup_arm_condbranch:
451   case ARM::fixup_arm_uncondbranch:
452   case ARM::fixup_t2_condbranch:
453   case ARM::fixup_t2_uncondbranch:
454   case ARM::fixup_arm_thumb_br:
455   case ARM::fixup_arm_uncondbl:
456   case ARM::fixup_arm_condbl:
457   case ARM::fixup_arm_blx:
458   case ARM::fixup_arm_thumb_bl:
459   case ARM::fixup_arm_thumb_blx:
460   case ARM::fixup_arm_thumb_cb:
461   case ARM::fixup_arm_thumb_cp:
462   case ARM::fixup_arm_thumb_bcc:
463   case ARM::fixup_bf_branch:
464   case ARM::fixup_bf_target:
465   case ARM::fixup_bfl_target:
466   case ARM::fixup_bfc_target:
467   case ARM::fixup_wls:
468   case ARM::fixup_le:
469     PCRel = true;
470   }
471   Fixups.push_back(MCFixup::create(Offset, Value, Kind, PCRel));
472 }
473 
474 /// NEONThumb2DataIPostEncoder - Post-process encoded NEON data-processing
475 /// instructions, and rewrite them to their Thumb2 form if we are currently in
476 /// Thumb2 mode.
477 unsigned ARMMCCodeEmitter::NEONThumb2DataIPostEncoder(const MCInst &MI,
478                                                  unsigned EncodedValue,
479                                                  const MCSubtargetInfo &STI) const {
480   if (isThumb2(STI)) {
481     // NEON Thumb2 data-processsing encodings are very simple: bit 24 is moved
482     // to bit 12 of the high half-word (i.e. bit 28), and bits 27-24 are
483     // set to 1111.
484     unsigned Bit24 = EncodedValue & 0x01000000;
485     unsigned Bit28 = Bit24 << 4;
486     EncodedValue &= 0xEFFFFFFF;
487     EncodedValue |= Bit28;
488     EncodedValue |= 0x0F000000;
489   }
490 
491   return EncodedValue;
492 }
493 
494 /// NEONThumb2LoadStorePostEncoder - Post-process encoded NEON load/store
495 /// instructions, and rewrite them to their Thumb2 form if we are currently in
496 /// Thumb2 mode.
497 unsigned ARMMCCodeEmitter::NEONThumb2LoadStorePostEncoder(const MCInst &MI,
498                                                  unsigned EncodedValue,
499                                                  const MCSubtargetInfo &STI) const {
500   if (isThumb2(STI)) {
501     EncodedValue &= 0xF0FFFFFF;
502     EncodedValue |= 0x09000000;
503   }
504 
505   return EncodedValue;
506 }
507 
508 /// NEONThumb2DupPostEncoder - Post-process encoded NEON vdup
509 /// instructions, and rewrite them to their Thumb2 form if we are currently in
510 /// Thumb2 mode.
511 unsigned ARMMCCodeEmitter::NEONThumb2DupPostEncoder(const MCInst &MI,
512                                                  unsigned EncodedValue,
513                                                  const MCSubtargetInfo &STI) const {
514   if (isThumb2(STI)) {
515     EncodedValue &= 0x00FFFFFF;
516     EncodedValue |= 0xEE000000;
517   }
518 
519   return EncodedValue;
520 }
521 
522 /// Post-process encoded NEON v8 instructions, and rewrite them to Thumb2 form
523 /// if we are in Thumb2.
524 unsigned ARMMCCodeEmitter::NEONThumb2V8PostEncoder(const MCInst &MI,
525                                                  unsigned EncodedValue,
526                                                  const MCSubtargetInfo &STI) const {
527   if (isThumb2(STI)) {
528     EncodedValue |= 0xC000000; // Set bits 27-26
529   }
530 
531   return EncodedValue;
532 }
533 
534 /// VFPThumb2PostEncoder - Post-process encoded VFP instructions and rewrite
535 /// them to their Thumb2 form if we are currently in Thumb2 mode.
536 unsigned ARMMCCodeEmitter::
537 VFPThumb2PostEncoder(const MCInst &MI, unsigned EncodedValue,
538                      const MCSubtargetInfo &STI) const {
539   if (isThumb2(STI)) {
540     EncodedValue &= 0x0FFFFFFF;
541     EncodedValue |= 0xE0000000;
542   }
543   return EncodedValue;
544 }
545 
546 /// getMachineOpValue - Return binary encoding of operand. If the machine
547 /// operand requires relocation, record the relocation and return zero.
548 unsigned ARMMCCodeEmitter::
549 getMachineOpValue(const MCInst &MI, const MCOperand &MO,
550                   SmallVectorImpl<MCFixup> &Fixups,
551                   const MCSubtargetInfo &STI) const {
552   if (MO.isReg()) {
553     MCRegister Reg = MO.getReg();
554     unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(Reg);
555 
556     // In NEON, Q registers are encoded as 2x their register number,
557     // because they're using the same indices as the D registers they
558     // overlap. In MVE, there are no 64-bit vector instructions, so
559     // the encodings all refer to Q-registers by their literal
560     // register number.
561 
562     if (STI.hasFeature(ARM::HasMVEIntegerOps))
563       return RegNo;
564 
565     switch (Reg.id()) {
566     default:
567       return RegNo;
568     case ARM::Q0:  case ARM::Q1:  case ARM::Q2:  case ARM::Q3:
569     case ARM::Q4:  case ARM::Q5:  case ARM::Q6:  case ARM::Q7:
570     case ARM::Q8:  case ARM::Q9:  case ARM::Q10: case ARM::Q11:
571     case ARM::Q12: case ARM::Q13: case ARM::Q14: case ARM::Q15:
572       return 2 * RegNo;
573     }
574   } else if (MO.isImm()) {
575     return static_cast<unsigned>(MO.getImm());
576   } else if (MO.isDFPImm()) {
577     return static_cast<unsigned>(APFloat(bit_cast<double>(MO.getDFPImm()))
578                                      .bitcastToAPInt()
579                                      .getHiBits(32)
580                                      .getLimitedValue());
581   }
582 
583   llvm_unreachable("Unable to encode MCOperand!");
584 }
585 
586 /// getAddrModeImmOpValue - Return encoding info for 'reg +/- imm' operand.
587 bool ARMMCCodeEmitter::
588 EncodeAddrModeOpValues(const MCInst &MI, unsigned OpIdx, unsigned &Reg,
589                        unsigned &Imm, SmallVectorImpl<MCFixup> &Fixups,
590                        const MCSubtargetInfo &STI) const {
591   const MCOperand &MO  = MI.getOperand(OpIdx);
592   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
593 
594   Reg = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
595 
596   int32_t SImm = MO1.getImm();
597   bool isAdd = true;
598 
599   // Special value for #-0
600   if (SImm == INT32_MIN) {
601     SImm = 0;
602     isAdd = false;
603   }
604 
605   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
606   if (SImm < 0) {
607     SImm = -SImm;
608     isAdd = false;
609   }
610 
611   Imm = SImm;
612   return isAdd;
613 }
614 
615 /// getBranchTargetOpValue - Helper function to get the branch target operand,
616 /// which is either an immediate or requires a fixup.
617 static uint32_t getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
618                                        unsigned FixupKind,
619                                        SmallVectorImpl<MCFixup> &Fixups,
620                                        const MCSubtargetInfo &STI) {
621   const MCOperand &MO = MI.getOperand(OpIdx);
622 
623   // If the destination is an immediate, we have nothing to do.
624   if (MO.isImm()) return MO.getImm();
625   assert(MO.isExpr() && "Unexpected branch target type!");
626   const MCExpr *Expr = MO.getExpr();
627   MCFixupKind Kind = MCFixupKind(FixupKind);
628   addFixup(Fixups, 0, Expr, Kind);
629 
630   // All of the information is in the fixup.
631   return 0;
632 }
633 
634 // Thumb BL and BLX use a strange offset encoding where bits 22 and 21 are
635 // determined by negating them and XOR'ing them with bit 23.
636 static int32_t encodeThumbBLOffset(int32_t offset) {
637   offset >>= 1;
638   uint32_t S  = (offset & 0x800000) >> 23;
639   uint32_t J1 = (offset & 0x400000) >> 22;
640   uint32_t J2 = (offset & 0x200000) >> 21;
641   J1 = (~J1 & 0x1);
642   J2 = (~J2 & 0x1);
643   J1 ^= S;
644   J2 ^= S;
645 
646   offset &= ~0x600000;
647   offset |= J1 << 22;
648   offset |= J2 << 21;
649 
650   return offset;
651 }
652 
653 /// getThumbBLTargetOpValue - Return encoding info for immediate branch target.
654 uint32_t ARMMCCodeEmitter::
655 getThumbBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
656                         SmallVectorImpl<MCFixup> &Fixups,
657                         const MCSubtargetInfo &STI) const {
658   const MCOperand MO = MI.getOperand(OpIdx);
659   if (MO.isExpr())
660     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_bl,
661                                     Fixups, STI);
662   return encodeThumbBLOffset(MO.getImm());
663 }
664 
665 /// getThumbBLXTargetOpValue - Return encoding info for Thumb immediate
666 /// BLX branch target.
667 uint32_t ARMMCCodeEmitter::
668 getThumbBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
669                          SmallVectorImpl<MCFixup> &Fixups,
670                          const MCSubtargetInfo &STI) const {
671   const MCOperand MO = MI.getOperand(OpIdx);
672   if (MO.isExpr())
673     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_blx,
674                                     Fixups, STI);
675   return encodeThumbBLOffset(MO.getImm());
676 }
677 
678 /// getThumbBRTargetOpValue - Return encoding info for Thumb branch target.
679 uint32_t ARMMCCodeEmitter::
680 getThumbBRTargetOpValue(const MCInst &MI, unsigned OpIdx,
681                         SmallVectorImpl<MCFixup> &Fixups,
682                         const MCSubtargetInfo &STI) const {
683   const MCOperand MO = MI.getOperand(OpIdx);
684   if (MO.isExpr())
685     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_br,
686                                     Fixups, STI);
687   return (MO.getImm() >> 1);
688 }
689 
690 /// getThumbBCCTargetOpValue - Return encoding info for Thumb branch target.
691 uint32_t ARMMCCodeEmitter::
692 getThumbBCCTargetOpValue(const MCInst &MI, unsigned OpIdx,
693                          SmallVectorImpl<MCFixup> &Fixups,
694                          const MCSubtargetInfo &STI) const {
695   const MCOperand MO = MI.getOperand(OpIdx);
696   if (MO.isExpr())
697     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_bcc,
698                                     Fixups, STI);
699   return (MO.getImm() >> 1);
700 }
701 
702 /// getThumbCBTargetOpValue - Return encoding info for Thumb branch target.
703 uint32_t ARMMCCodeEmitter::
704 getThumbCBTargetOpValue(const MCInst &MI, unsigned OpIdx,
705                         SmallVectorImpl<MCFixup> &Fixups,
706                         const MCSubtargetInfo &STI) const {
707   const MCOperand MO = MI.getOperand(OpIdx);
708   if (MO.isExpr())
709     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_cb, Fixups, STI);
710   return (MO.getImm() >> 1);
711 }
712 
713 /// Return true if this branch has a non-always predication
714 static bool HasConditionalBranch(const MCInst &MI) {
715   int NumOp = MI.getNumOperands();
716   if (NumOp >= 2) {
717     for (int i = 0; i < NumOp-1; ++i) {
718       const MCOperand &MCOp1 = MI.getOperand(i);
719       const MCOperand &MCOp2 = MI.getOperand(i + 1);
720       if (MCOp1.isImm() && MCOp2.isReg() &&
721           (!MCOp2.getReg() || MCOp2.getReg() == ARM::CPSR)) {
722         if (ARMCC::CondCodes(MCOp1.getImm()) != ARMCC::AL)
723           return true;
724       }
725     }
726   }
727   return false;
728 }
729 
730 /// getBranchTargetOpValue - Return encoding info for 24-bit immediate branch
731 /// target.
732 uint32_t ARMMCCodeEmitter::
733 getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
734                        SmallVectorImpl<MCFixup> &Fixups,
735                        const MCSubtargetInfo &STI) const {
736   // FIXME: This really, really shouldn't use TargetMachine. We don't want
737   // coupling between MC and TM anywhere we can help it.
738   if (isThumb2(STI))
739     return
740       ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_condbranch, Fixups, STI);
741   return getARMBranchTargetOpValue(MI, OpIdx, Fixups, STI);
742 }
743 
744 /// getBranchTargetOpValue - Return encoding info for 24-bit immediate branch
745 /// target.
746 uint32_t ARMMCCodeEmitter::
747 getARMBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
748                           SmallVectorImpl<MCFixup> &Fixups,
749                           const MCSubtargetInfo &STI) const {
750   const MCOperand MO = MI.getOperand(OpIdx);
751   if (MO.isExpr()) {
752     if (HasConditionalBranch(MI))
753       return ::getBranchTargetOpValue(MI, OpIdx,
754                                       ARM::fixup_arm_condbranch, Fixups, STI);
755     return ::getBranchTargetOpValue(MI, OpIdx,
756                                     ARM::fixup_arm_uncondbranch, Fixups, STI);
757   }
758 
759   return MO.getImm() >> 2;
760 }
761 
762 uint32_t ARMMCCodeEmitter::
763 getARMBLTargetOpValue(const MCInst &MI, unsigned OpIdx,
764                           SmallVectorImpl<MCFixup> &Fixups,
765                           const MCSubtargetInfo &STI) const {
766   const MCOperand MO = MI.getOperand(OpIdx);
767   if (MO.isExpr()) {
768     if (HasConditionalBranch(MI))
769       return ::getBranchTargetOpValue(MI, OpIdx,
770                                       ARM::fixup_arm_condbl, Fixups, STI);
771     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_uncondbl, Fixups, STI);
772   }
773 
774   return MO.getImm() >> 2;
775 }
776 
777 uint32_t ARMMCCodeEmitter::
778 getARMBLXTargetOpValue(const MCInst &MI, unsigned OpIdx,
779                           SmallVectorImpl<MCFixup> &Fixups,
780                           const MCSubtargetInfo &STI) const {
781   const MCOperand MO = MI.getOperand(OpIdx);
782   if (MO.isExpr())
783     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_blx, Fixups, STI);
784 
785   return MO.getImm() >> 1;
786 }
787 
788 /// getUnconditionalBranchTargetOpValue - Return encoding info for 24-bit
789 /// immediate branch target.
790 uint32_t ARMMCCodeEmitter::getThumbBranchTargetOpValue(
791     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
792     const MCSubtargetInfo &STI) const {
793   unsigned Val = 0;
794   const MCOperand MO = MI.getOperand(OpIdx);
795 
796   if(MO.isExpr())
797     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_uncondbranch, Fixups, STI);
798   else
799     Val = MO.getImm() >> 1;
800 
801   bool I  = (Val & 0x800000);
802   bool J1 = (Val & 0x400000);
803   bool J2 = (Val & 0x200000);
804   if (I ^ J1)
805     Val &= ~0x400000;
806   else
807     Val |= 0x400000;
808 
809   if (I ^ J2)
810     Val &= ~0x200000;
811   else
812     Val |= 0x200000;
813 
814   return Val;
815 }
816 
817 /// getAdrLabelOpValue - Return encoding info for 12-bit shifted-immediate
818 /// ADR label target.
819 uint32_t ARMMCCodeEmitter::
820 getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
821                    SmallVectorImpl<MCFixup> &Fixups,
822                    const MCSubtargetInfo &STI) const {
823   const MCOperand MO = MI.getOperand(OpIdx);
824   if (MO.isExpr())
825     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_adr_pcrel_12,
826                                     Fixups, STI);
827   int64_t offset = MO.getImm();
828   uint32_t Val = 0x2000;
829 
830   int SoImmVal;
831   if (offset == INT32_MIN) {
832     Val = 0x1000;
833     SoImmVal = 0;
834   } else if (offset < 0) {
835     Val = 0x1000;
836     offset *= -1;
837     SoImmVal = ARM_AM::getSOImmVal(offset);
838     if(SoImmVal == -1) {
839       Val = 0x2000;
840       offset *= -1;
841       SoImmVal = ARM_AM::getSOImmVal(offset);
842     }
843   } else {
844     SoImmVal = ARM_AM::getSOImmVal(offset);
845     if(SoImmVal == -1) {
846       Val = 0x1000;
847       offset *= -1;
848       SoImmVal = ARM_AM::getSOImmVal(offset);
849     }
850   }
851 
852   assert(SoImmVal != -1 && "Not a valid so_imm value!");
853 
854   Val |= SoImmVal;
855   return Val;
856 }
857 
858 /// getT2AdrLabelOpValue - Return encoding info for 12-bit immediate ADR label
859 /// target.
860 uint32_t ARMMCCodeEmitter::
861 getT2AdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
862                    SmallVectorImpl<MCFixup> &Fixups,
863                    const MCSubtargetInfo &STI) const {
864   const MCOperand MO = MI.getOperand(OpIdx);
865   if (MO.isExpr())
866     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_adr_pcrel_12,
867                                     Fixups, STI);
868   int32_t Val = MO.getImm();
869   if (Val == INT32_MIN)
870     Val = 0x1000;
871   else if (Val < 0) {
872     Val *= -1;
873     Val |= 0x1000;
874   }
875   return Val;
876 }
877 
878 /// getITMaskOpValue - Return the architectural encoding of an IT
879 /// predication mask, given the MCOperand format.
880 uint32_t ARMMCCodeEmitter::
881 getITMaskOpValue(const MCInst &MI, unsigned OpIdx,
882                  SmallVectorImpl<MCFixup> &Fixups,
883                  const MCSubtargetInfo &STI) const {
884   const MCOperand MaskMO = MI.getOperand(OpIdx);
885   assert(MaskMO.isImm() && "Unexpected operand type!");
886 
887   unsigned Mask = MaskMO.getImm();
888 
889   // IT masks are encoded as a sequence of replacement low-order bits
890   // for the condition code. So if the low bit of the starting
891   // condition code is 1, then we have to flip all the bits above the
892   // terminating bit (which is the lowest 1 bit).
893   assert(OpIdx > 0 && "IT mask appears first!");
894   const MCOperand CondMO = MI.getOperand(OpIdx-1);
895   assert(CondMO.isImm() && "Unexpected operand type!");
896   if (CondMO.getImm() & 1) {
897     unsigned LowBit = Mask & -Mask;
898     unsigned BitsAboveLowBit = 0xF & (-LowBit << 1);
899     Mask ^= BitsAboveLowBit;
900   }
901 
902   return Mask;
903 }
904 
905 /// getThumbAdrLabelOpValue - Return encoding info for 8-bit immediate ADR label
906 /// target.
907 uint32_t ARMMCCodeEmitter::
908 getThumbAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
909                    SmallVectorImpl<MCFixup> &Fixups,
910                    const MCSubtargetInfo &STI) const {
911   const MCOperand MO = MI.getOperand(OpIdx);
912   if (MO.isExpr())
913     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_thumb_adr_pcrel_10,
914                                     Fixups, STI);
915   return MO.getImm();
916 }
917 
918 /// getThumbAddrModeRegRegOpValue - Return encoding info for 'reg + reg'
919 /// operand.
920 uint32_t ARMMCCodeEmitter::
921 getThumbAddrModeRegRegOpValue(const MCInst &MI, unsigned OpIdx,
922                               SmallVectorImpl<MCFixup> &,
923                               const MCSubtargetInfo &STI) const {
924   // [Rn, Rm]
925   //   {5-3} = Rm
926   //   {2-0} = Rn
927   const MCOperand &MO1 = MI.getOperand(OpIdx);
928   const MCOperand &MO2 = MI.getOperand(OpIdx + 1);
929   unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
930   unsigned Rm = CTX.getRegisterInfo()->getEncodingValue(MO2.getReg());
931   return (Rm << 3) | Rn;
932 }
933 
934 /// getMVEShiftImmOpValue - Return encoding info for the 'sz:imm5'
935 /// operand.
936 uint32_t
937 ARMMCCodeEmitter::getMVEShiftImmOpValue(const MCInst &MI, unsigned OpIdx,
938                                         SmallVectorImpl<MCFixup> &Fixups,
939                                         const MCSubtargetInfo &STI) const {
940   // {4-0} = szimm5
941   // The value we are trying to encode is an immediate between either the
942   // range of [1-7] or [1-15] depending on whether we are dealing with the
943   // u8/s8 or the u16/s16 variants respectively.
944   // This value is encoded as follows, if ShiftImm is the value within those
945   // ranges then the encoding szimm5 = ShiftImm + size, where size is either 8
946   // or 16.
947 
948   unsigned Size, ShiftImm;
949   switch(MI.getOpcode()) {
950     case ARM::MVE_VSHLL_imms16bh:
951     case ARM::MVE_VSHLL_imms16th:
952     case ARM::MVE_VSHLL_immu16bh:
953     case ARM::MVE_VSHLL_immu16th:
954       Size = 16;
955       break;
956     case ARM::MVE_VSHLL_imms8bh:
957     case ARM::MVE_VSHLL_imms8th:
958     case ARM::MVE_VSHLL_immu8bh:
959     case ARM::MVE_VSHLL_immu8th:
960       Size = 8;
961       break;
962     default:
963       llvm_unreachable("Use of operand not supported by this instruction");
964   }
965   ShiftImm = MI.getOperand(OpIdx).getImm();
966   return Size + ShiftImm;
967 }
968 
969 /// getAddrModeImm12OpValue - Return encoding info for 'reg +/- imm12' operand.
970 uint32_t ARMMCCodeEmitter::
971 getAddrModeImm12OpValue(const MCInst &MI, unsigned OpIdx,
972                         SmallVectorImpl<MCFixup> &Fixups,
973                         const MCSubtargetInfo &STI) const {
974   // {17-13} = reg
975   // {12}    = (U)nsigned (add == '1', sub == '0')
976   // {11-0}  = imm12
977   unsigned Reg = 0, Imm12 = 0;
978   bool isAdd = true;
979   // If The first operand isn't a register, we have a label reference.
980   const MCOperand &MO = MI.getOperand(OpIdx);
981   if (MO.isReg()) {
982     const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
983     if (MO1.isImm()) {
984       isAdd = EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm12, Fixups, STI);
985     } else if (MO1.isExpr()) {
986       assert(!isThumb(STI) && !isThumb2(STI) &&
987              "Thumb mode requires different encoding");
988       Reg = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
989       isAdd = false; // 'U' bit is set as part of the fixup.
990       MCFixupKind Kind = ARM::fixup_arm_ldst_abs_12;
991       addFixup(Fixups, 0, MO1.getExpr(), Kind);
992     }
993   } else if (MO.isExpr()) {
994     Reg = CTX.getRegisterInfo()->getEncodingValue(ARM::PC); // Rn is PC.
995     isAdd = false; // 'U' bit is set as part of the fixup.
996     MCFixupKind Kind;
997     if (isThumb2(STI))
998       Kind = ARM::fixup_t2_ldst_pcrel_12;
999     else
1000       Kind = ARM::fixup_arm_ldst_pcrel_12;
1001     addFixup(Fixups, 0, MO.getExpr(), Kind);
1002 
1003     ++MCNumCPRelocations;
1004   } else {
1005     Reg = ARM::PC;
1006     int32_t Offset = MO.getImm();
1007     if (Offset == INT32_MIN) {
1008       Offset = 0;
1009       isAdd = false;
1010     } else if (Offset < 0) {
1011       Offset *= -1;
1012       isAdd = false;
1013     }
1014     Imm12 = Offset;
1015   }
1016   uint32_t Binary = Imm12 & 0xfff;
1017   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1018   if (isAdd)
1019     Binary |= (1 << 12);
1020   Binary |= (Reg << 13);
1021   return Binary;
1022 }
1023 
1024 template<unsigned Bits, unsigned Shift>
1025 uint32_t ARMMCCodeEmitter::
1026 getT2ScaledImmOpValue(const MCInst &MI, unsigned OpIdx,
1027                       SmallVectorImpl<MCFixup> &Fixups,
1028                       const MCSubtargetInfo &STI) const {
1029   // FIXME: The immediate operand should have already been encoded like this
1030   // before ever getting here. The encoder method should just need to combine
1031   // the MI operands for the register and the offset into a single
1032   // representation for the complex operand in the .td file. This isn't just
1033   // style, unfortunately. As-is, we can't represent the distinct encoding
1034   // for #-0.
1035 
1036   // {Bits}    = (U)nsigned (add == '1', sub == '0')
1037   // {(Bits-1)-0}  = immediate
1038   int32_t Imm = MI.getOperand(OpIdx).getImm();
1039   bool isAdd = Imm >= 0;
1040 
1041   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1042   if (Imm < 0)
1043     Imm = -(uint32_t)Imm;
1044 
1045   Imm >>= Shift;
1046 
1047   uint32_t Binary = Imm & ((1U << Bits) - 1);
1048   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1049   if (isAdd)
1050     Binary |= (1U << Bits);
1051   return Binary;
1052 }
1053 
1054 /// getMveAddrModeRQOpValue - Return encoding info for 'reg, vreg'
1055 /// operand.
1056 uint32_t ARMMCCodeEmitter::
1057 getMveAddrModeRQOpValue(const MCInst &MI, unsigned OpIdx,
1058                         SmallVectorImpl<MCFixup> &Fixups,
1059                         const MCSubtargetInfo &STI) const {
1060     // {6-3} Rn
1061     // {2-0} Qm
1062     const MCOperand &M0 = MI.getOperand(OpIdx);
1063     const MCOperand &M1 = MI.getOperand(OpIdx + 1);
1064 
1065     unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(M0.getReg());
1066     unsigned Qm = CTX.getRegisterInfo()->getEncodingValue(M1.getReg());
1067 
1068     assert(Qm < 8 && "Qm is supposed to be encodable in 3 bits");
1069 
1070     return (Rn << 3) | Qm;
1071 }
1072 
1073 /// getMveAddrModeRQOpValue - Return encoding info for 'reg, vreg'
1074 /// operand.
1075 template<int shift>
1076 uint32_t ARMMCCodeEmitter::
1077 getMveAddrModeQOpValue(const MCInst &MI, unsigned OpIdx,
1078                         SmallVectorImpl<MCFixup> &Fixups,
1079                         const MCSubtargetInfo &STI) const {
1080     // {10-8} Qm
1081     // {7-0} Imm
1082     const MCOperand &M0 = MI.getOperand(OpIdx);
1083     const MCOperand &M1 = MI.getOperand(OpIdx + 1);
1084 
1085     unsigned Qm = CTX.getRegisterInfo()->getEncodingValue(M0.getReg());
1086     int32_t Imm = M1.getImm();
1087 
1088     bool isAdd = Imm >= 0;
1089 
1090     Imm >>= shift;
1091 
1092     if (!isAdd)
1093       Imm = -(uint32_t)Imm;
1094 
1095     Imm &= 0x7f;
1096 
1097     if (isAdd)
1098       Imm |= 0x80;
1099 
1100     assert(Qm < 8 && "Qm is supposed to be encodable in 3 bits");
1101 
1102     return (Qm << 8) | Imm;
1103 }
1104 
1105 /// getT2AddrModeImm8s4OpValue - Return encoding info for
1106 /// 'reg +/- imm8<<2' operand.
1107 uint32_t ARMMCCodeEmitter::
1108 getT2AddrModeImm8s4OpValue(const MCInst &MI, unsigned OpIdx,
1109                         SmallVectorImpl<MCFixup> &Fixups,
1110                         const MCSubtargetInfo &STI) const {
1111   // {12-9} = reg
1112   // {8}    = (U)nsigned (add == '1', sub == '0')
1113   // {7-0}  = imm8
1114   unsigned Reg, Imm8;
1115   bool isAdd = true;
1116   // If The first operand isn't a register, we have a label reference.
1117   const MCOperand &MO = MI.getOperand(OpIdx);
1118   if (!MO.isReg()) {
1119     Reg = CTX.getRegisterInfo()->getEncodingValue(ARM::PC);   // Rn is PC.
1120     Imm8 = 0;
1121     isAdd = false ; // 'U' bit is set as part of the fixup.
1122 
1123     assert(MO.isExpr() && "Unexpected machine operand type!");
1124     const MCExpr *Expr = MO.getExpr();
1125     MCFixupKind Kind = ARM::fixup_t2_pcrel_10;
1126     addFixup(Fixups, 0, Expr, Kind);
1127 
1128     ++MCNumCPRelocations;
1129   } else
1130     isAdd = EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm8, Fixups, STI);
1131 
1132   // FIXME: The immediate operand should have already been encoded like this
1133   // before ever getting here. The encoder method should just need to combine
1134   // the MI operands for the register and the offset into a single
1135   // representation for the complex operand in the .td file. This isn't just
1136   // style, unfortunately. As-is, we can't represent the distinct encoding
1137   // for #-0.
1138   assert(((Imm8 & 0x3) == 0) && "Not a valid immediate!");
1139   uint32_t Binary = (Imm8 >> 2) & 0xff;
1140   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1141   if (isAdd)
1142     Binary |= (1 << 8);
1143   Binary |= (Reg << 9);
1144   return Binary;
1145 }
1146 
1147 /// getT2AddrModeImm7s4OpValue - Return encoding info for
1148 /// 'reg +/- imm7<<2' operand.
1149 uint32_t
1150 ARMMCCodeEmitter::getT2AddrModeImm7s4OpValue(const MCInst &MI, unsigned OpIdx,
1151                                              SmallVectorImpl<MCFixup> &Fixups,
1152                                              const MCSubtargetInfo &STI) const {
1153   // {11-8} = reg
1154   // {7}    = (A)dd (add == '1', sub == '0')
1155   // {6-0}  = imm7
1156   unsigned Reg, Imm7;
1157   // If The first operand isn't a register, we have a label reference.
1158   bool isAdd = EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm7, Fixups, STI);
1159 
1160   // FIXME: The immediate operand should have already been encoded like this
1161   // before ever getting here. The encoder method should just need to combine
1162   // the MI operands for the register and the offset into a single
1163   // representation for the complex operand in the .td file. This isn't just
1164   // style, unfortunately. As-is, we can't represent the distinct encoding
1165   // for #-0.
1166   uint32_t Binary = (Imm7 >> 2) & 0xff;
1167   // Immediate is always encoded as positive. The 'A' bit controls add vs sub.
1168   if (isAdd)
1169     Binary |= (1 << 7);
1170   Binary |= (Reg << 8);
1171   return Binary;
1172 }
1173 
1174 /// getT2AddrModeImm0_1020s4OpValue - Return encoding info for
1175 /// 'reg + imm8<<2' operand.
1176 uint32_t ARMMCCodeEmitter::
1177 getT2AddrModeImm0_1020s4OpValue(const MCInst &MI, unsigned OpIdx,
1178                         SmallVectorImpl<MCFixup> &Fixups,
1179                         const MCSubtargetInfo &STI) const {
1180   // {11-8} = reg
1181   // {7-0}  = imm8
1182   const MCOperand &MO = MI.getOperand(OpIdx);
1183   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1184   unsigned Reg = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1185   unsigned Imm8 = MO1.getImm();
1186   return (Reg << 8) | Imm8;
1187 }
1188 
1189 uint32_t ARMMCCodeEmitter::getHiLoImmOpValue(const MCInst &MI, unsigned OpIdx,
1190                                              SmallVectorImpl<MCFixup> &Fixups,
1191                                              const MCSubtargetInfo &STI) const {
1192   // {20-16} = imm{15-12}
1193   // {11-0}  = imm{11-0}
1194   const MCOperand &MO = MI.getOperand(OpIdx);
1195   if (MO.isImm())
1196     // Hi / lo bits already extracted during earlier passes.
1197     return static_cast<unsigned>(MO.getImm());
1198 
1199   // Handle :upper16:, :lower16:, :upper8_15:, :upper0_7:, :lower8_15:
1200   // :lower0_7: assembly prefixes.
1201   const MCExpr *E = MO.getExpr();
1202   MCFixupKind Kind;
1203   if (E->getKind() == MCExpr::Specifier) {
1204     auto *ARM16Expr = cast<MCSpecifierExpr>(E);
1205     E = ARM16Expr->getSubExpr();
1206 
1207     if (const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(E)) {
1208       const int64_t Value = MCE->getValue();
1209       if (Value > UINT32_MAX)
1210         report_fatal_error("constant value truncated (limited to 32-bit)");
1211 
1212       switch (ARM16Expr->getSpecifier()) {
1213       case ARM::S_HI16:
1214         return (int32_t(Value) & 0xffff0000) >> 16;
1215       case ARM::S_LO16:
1216         return (int32_t(Value) & 0x0000ffff);
1217 
1218       case ARM::S_HI_8_15:
1219         return (int32_t(Value) & 0xff000000) >> 24;
1220       case ARM::S_HI_0_7:
1221         return (int32_t(Value) & 0x00ff0000) >> 16;
1222       case ARM::S_LO_8_15:
1223         return (int32_t(Value) & 0x0000ff00) >> 8;
1224       case ARM::S_LO_0_7:
1225         return (int32_t(Value) & 0x000000ff);
1226 
1227       default: llvm_unreachable("Unsupported ARMFixup");
1228       }
1229     }
1230 
1231     switch (ARM16Expr->getSpecifier()) {
1232     default: llvm_unreachable("Unsupported ARMFixup");
1233     case ARM::S_HI16:
1234       Kind = MCFixupKind(isThumb(STI) ? ARM::fixup_t2_movt_hi16
1235                                       : ARM::fixup_arm_movt_hi16);
1236       break;
1237     case ARM::S_LO16:
1238       Kind = MCFixupKind(isThumb(STI) ? ARM::fixup_t2_movw_lo16
1239                                       : ARM::fixup_arm_movw_lo16);
1240       break;
1241     case ARM::S_HI_8_15:
1242       if (!isThumb(STI))
1243         llvm_unreachable(":upper_8_15: not supported in Arm state");
1244       Kind = ARM::fixup_arm_thumb_upper_8_15;
1245       break;
1246     case ARM::S_HI_0_7:
1247       if (!isThumb(STI))
1248         llvm_unreachable(":upper_0_7: not supported in Arm state");
1249       Kind = ARM::fixup_arm_thumb_upper_0_7;
1250       break;
1251     case ARM::S_LO_8_15:
1252       if (!isThumb(STI))
1253         llvm_unreachable(":lower_8_15: not supported in Arm state");
1254       Kind = ARM::fixup_arm_thumb_lower_8_15;
1255       break;
1256     case ARM::S_LO_0_7:
1257       if (!isThumb(STI))
1258         llvm_unreachable(":lower_0_7: not supported in Arm state");
1259       Kind = ARM::fixup_arm_thumb_lower_0_7;
1260       break;
1261     }
1262 
1263     addFixup(Fixups, 0, E, Kind);
1264     return 0;
1265   }
1266   // If the expression doesn't have :upper16:, :lower16: on it, it's just a
1267   // plain immediate expression, previously those evaluated to the lower 16 bits
1268   // of the expression regardless of whether we have a movt or a movw, but that
1269   // led to misleadingly results.  This is disallowed in the AsmParser in
1270   // validateInstruction() so this should never happen.  The same holds for
1271   // thumb1 :upper8_15:, :upper0_7:, lower8_15: or :lower0_7: with movs or adds.
1272   llvm_unreachable("expression without :upper16:, :lower16:, :upper8_15:,"
1273                    ":upper0_7:, lower8_15: or :lower0_7:");
1274 }
1275 
1276 uint32_t ARMMCCodeEmitter::
1277 getLdStSORegOpValue(const MCInst &MI, unsigned OpIdx,
1278                     SmallVectorImpl<MCFixup> &Fixups,
1279                     const MCSubtargetInfo &STI) const {
1280   const MCOperand &MO = MI.getOperand(OpIdx);
1281   const MCOperand &MO1 = MI.getOperand(OpIdx+1);
1282   const MCOperand &MO2 = MI.getOperand(OpIdx+2);
1283   unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1284   unsigned Rm = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
1285   unsigned ShImm = ARM_AM::getAM2Offset(MO2.getImm());
1286   bool isAdd = ARM_AM::getAM2Op(MO2.getImm()) == ARM_AM::add;
1287   ARM_AM::ShiftOpc ShOp = ARM_AM::getAM2ShiftOpc(MO2.getImm());
1288   unsigned SBits = getShiftOp(ShOp);
1289 
1290   // While "lsr #32" and "asr #32" exist, they are encoded with a 0 in the shift
1291   // amount. However, it would be an easy mistake to make so check here.
1292   assert((ShImm & ~0x1f) == 0 && "Out of range shift amount");
1293 
1294   // {16-13} = Rn
1295   // {12}    = isAdd
1296   // {11-0}  = shifter
1297   //  {3-0}  = Rm
1298   //  {4}    = 0
1299   //  {6-5}  = type
1300   //  {11-7} = imm
1301   uint32_t Binary = Rm;
1302   Binary |= Rn << 13;
1303   Binary |= SBits << 5;
1304   Binary |= ShImm << 7;
1305   if (isAdd)
1306     Binary |= 1 << 12;
1307   return Binary;
1308 }
1309 
1310 uint32_t ARMMCCodeEmitter::
1311 getAddrMode2OffsetOpValue(const MCInst &MI, unsigned OpIdx,
1312                           SmallVectorImpl<MCFixup> &Fixups,
1313                           const MCSubtargetInfo &STI) const {
1314   // {13}     1 == imm12, 0 == Rm
1315   // {12}     isAdd
1316   // {11-0}   imm12/Rm
1317   const MCOperand &MO = MI.getOperand(OpIdx);
1318   const MCOperand &MO1 = MI.getOperand(OpIdx+1);
1319   unsigned Imm = MO1.getImm();
1320   bool isAdd = ARM_AM::getAM2Op(Imm) == ARM_AM::add;
1321   bool isReg = MO.getReg().isValid();
1322   uint32_t Binary = ARM_AM::getAM2Offset(Imm);
1323   // if reg +/- reg, Rm will be non-zero. Otherwise, we have reg +/- imm12
1324   if (isReg) {
1325     ARM_AM::ShiftOpc ShOp = ARM_AM::getAM2ShiftOpc(Imm);
1326     Binary <<= 7;                    // Shift amount is bits [11:7]
1327     Binary |= getShiftOp(ShOp) << 5; // Shift type is bits [6:5]
1328     Binary |= CTX.getRegisterInfo()->getEncodingValue(MO.getReg()); // Rm is bits [3:0]
1329   }
1330   return Binary | (isAdd << 12) | (isReg << 13);
1331 }
1332 
1333 uint32_t ARMMCCodeEmitter::
1334 getPostIdxRegOpValue(const MCInst &MI, unsigned OpIdx,
1335                      SmallVectorImpl<MCFixup> &Fixups,
1336                      const MCSubtargetInfo &STI) const {
1337   // {4}      isAdd
1338   // {3-0}    Rm
1339   const MCOperand &MO = MI.getOperand(OpIdx);
1340   const MCOperand &MO1 = MI.getOperand(OpIdx+1);
1341   bool isAdd = MO1.getImm() != 0;
1342   return CTX.getRegisterInfo()->getEncodingValue(MO.getReg()) | (isAdd << 4);
1343 }
1344 
1345 uint32_t ARMMCCodeEmitter::
1346 getAddrMode3OffsetOpValue(const MCInst &MI, unsigned OpIdx,
1347                           SmallVectorImpl<MCFixup> &Fixups,
1348                           const MCSubtargetInfo &STI) const {
1349   // {9}      1 == imm8, 0 == Rm
1350   // {8}      isAdd
1351   // {7-4}    imm7_4/zero
1352   // {3-0}    imm3_0/Rm
1353   const MCOperand &MO = MI.getOperand(OpIdx);
1354   const MCOperand &MO1 = MI.getOperand(OpIdx+1);
1355   unsigned Imm = MO1.getImm();
1356   bool isAdd = ARM_AM::getAM3Op(Imm) == ARM_AM::add;
1357   bool isImm = !MO.getReg().isValid();
1358   uint32_t Imm8 = ARM_AM::getAM3Offset(Imm);
1359   // if reg +/- reg, Rm will be non-zero. Otherwise, we have reg +/- imm8
1360   if (!isImm)
1361     Imm8 = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1362   return Imm8 | (isAdd << 8) | (isImm << 9);
1363 }
1364 
1365 uint32_t ARMMCCodeEmitter::
1366 getAddrMode3OpValue(const MCInst &MI, unsigned OpIdx,
1367                     SmallVectorImpl<MCFixup> &Fixups,
1368                     const MCSubtargetInfo &STI) const {
1369   // {13}     1 == imm8, 0 == Rm
1370   // {12-9}   Rn
1371   // {8}      isAdd
1372   // {7-4}    imm7_4/zero
1373   // {3-0}    imm3_0/Rm
1374   const MCOperand &MO = MI.getOperand(OpIdx);
1375   const MCOperand &MO1 = MI.getOperand(OpIdx+1);
1376   const MCOperand &MO2 = MI.getOperand(OpIdx+2);
1377 
1378   // If The first operand isn't a register, we have a label reference.
1379   if (!MO.isReg()) {
1380     unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(ARM::PC);   // Rn is PC.
1381 
1382     assert(MO.isExpr() && "Unexpected machine operand type!");
1383     const MCExpr *Expr = MO.getExpr();
1384     MCFixupKind Kind = ARM::fixup_arm_pcrel_10_unscaled;
1385     addFixup(Fixups, 0, Expr, Kind);
1386 
1387     ++MCNumCPRelocations;
1388     return (Rn << 9) | (1 << 13);
1389   }
1390   unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1391   unsigned Imm = MO2.getImm();
1392   bool isAdd = ARM_AM::getAM3Op(Imm) == ARM_AM::add;
1393   bool isImm = !MO1.getReg().isValid();
1394   uint32_t Imm8 = ARM_AM::getAM3Offset(Imm);
1395   // if reg +/- reg, Rm will be non-zero. Otherwise, we have reg +/- imm8
1396   if (!isImm)
1397     Imm8 = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
1398   return (Rn << 9) | Imm8 | (isAdd << 8) | (isImm << 13);
1399 }
1400 
1401 /// getAddrModeThumbSPOpValue - Encode the t_addrmode_sp operands.
1402 uint32_t ARMMCCodeEmitter::
1403 getAddrModeThumbSPOpValue(const MCInst &MI, unsigned OpIdx,
1404                           SmallVectorImpl<MCFixup> &Fixups,
1405                           const MCSubtargetInfo &STI) const {
1406   // [SP, #imm]
1407   //   {7-0} = imm8
1408   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1409   assert(MI.getOperand(OpIdx).getReg() == ARM::SP &&
1410          "Unexpected base register!");
1411 
1412   // The immediate is already shifted for the implicit zeroes, so no change
1413   // here.
1414   return MO1.getImm() & 0xff;
1415 }
1416 
1417 /// getAddrModeISOpValue - Encode the t_addrmode_is# operands.
1418 uint32_t ARMMCCodeEmitter::
1419 getAddrModeISOpValue(const MCInst &MI, unsigned OpIdx,
1420                      SmallVectorImpl<MCFixup> &Fixups,
1421                      const MCSubtargetInfo &STI) const {
1422   // [Rn, #imm]
1423   //   {7-3} = imm5
1424   //   {2-0} = Rn
1425   const MCOperand &MO = MI.getOperand(OpIdx);
1426   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1427   unsigned Rn = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1428   unsigned Imm5 = MO1.getImm();
1429   return ((Imm5 & 0x1f) << 3) | Rn;
1430 }
1431 
1432 /// getAddrModePCOpValue - Return encoding for t_addrmode_pc operands.
1433 uint32_t ARMMCCodeEmitter::
1434 getAddrModePCOpValue(const MCInst &MI, unsigned OpIdx,
1435                      SmallVectorImpl<MCFixup> &Fixups,
1436                      const MCSubtargetInfo &STI) const {
1437   const MCOperand MO = MI.getOperand(OpIdx);
1438   if (MO.isExpr())
1439     return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_thumb_cp, Fixups, STI);
1440   return (MO.getImm() >> 2);
1441 }
1442 
1443 /// getAddrMode5OpValue - Return encoding info for 'reg +/- (imm8 << 2)' operand.
1444 uint32_t ARMMCCodeEmitter::
1445 getAddrMode5OpValue(const MCInst &MI, unsigned OpIdx,
1446                     SmallVectorImpl<MCFixup> &Fixups,
1447                     const MCSubtargetInfo &STI) const {
1448   // {12-9} = reg
1449   // {8}    = (U)nsigned (add == '1', sub == '0')
1450   // {7-0}  = imm8
1451   unsigned Reg, Imm8;
1452   bool isAdd;
1453   // If The first operand isn't a register, we have a label reference.
1454   const MCOperand &MO = MI.getOperand(OpIdx);
1455   if (!MO.isReg()) {
1456     Reg = CTX.getRegisterInfo()->getEncodingValue(ARM::PC);   // Rn is PC.
1457     Imm8 = 0;
1458     isAdd = false; // 'U' bit is handled as part of the fixup.
1459 
1460     assert(MO.isExpr() && "Unexpected machine operand type!");
1461     const MCExpr *Expr = MO.getExpr();
1462     MCFixupKind Kind;
1463     if (isThumb2(STI))
1464       Kind = ARM::fixup_t2_pcrel_10;
1465     else
1466       Kind = ARM::fixup_arm_pcrel_10;
1467     addFixup(Fixups, 0, Expr, Kind);
1468 
1469     ++MCNumCPRelocations;
1470   } else {
1471     EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm8, Fixups, STI);
1472     isAdd = ARM_AM::getAM5Op(Imm8) == ARM_AM::add;
1473   }
1474 
1475   uint32_t Binary = ARM_AM::getAM5Offset(Imm8);
1476   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1477   if (isAdd)
1478     Binary |= (1 << 8);
1479   Binary |= (Reg << 9);
1480   return Binary;
1481 }
1482 
1483 /// getAddrMode5FP16OpValue - Return encoding info for 'reg +/- (imm8 << 1)' operand.
1484 uint32_t ARMMCCodeEmitter::
1485 getAddrMode5FP16OpValue(const MCInst &MI, unsigned OpIdx,
1486                     SmallVectorImpl<MCFixup> &Fixups,
1487                     const MCSubtargetInfo &STI) const {
1488   // {12-9} = reg
1489   // {8}    = (U)nsigned (add == '1', sub == '0')
1490   // {7-0}  = imm8
1491   unsigned Reg, Imm8;
1492   bool isAdd;
1493   // If The first operand isn't a register, we have a label reference.
1494   const MCOperand &MO = MI.getOperand(OpIdx);
1495   if (!MO.isReg()) {
1496     Reg = CTX.getRegisterInfo()->getEncodingValue(ARM::PC);   // Rn is PC.
1497     Imm8 = 0;
1498     isAdd = false; // 'U' bit is handled as part of the fixup.
1499 
1500     assert(MO.isExpr() && "Unexpected machine operand type!");
1501     const MCExpr *Expr = MO.getExpr();
1502     MCFixupKind Kind;
1503     if (isThumb2(STI))
1504       Kind = ARM::fixup_t2_pcrel_9;
1505     else
1506       Kind = ARM::fixup_arm_pcrel_9;
1507     addFixup(Fixups, 0, Expr, Kind);
1508 
1509     ++MCNumCPRelocations;
1510   } else {
1511     EncodeAddrModeOpValues(MI, OpIdx, Reg, Imm8, Fixups, STI);
1512     isAdd = ARM_AM::getAM5Op(Imm8) == ARM_AM::add;
1513   }
1514 
1515   uint32_t Binary = ARM_AM::getAM5Offset(Imm8);
1516   // Immediate is always encoded as positive. The 'U' bit controls add vs sub.
1517   if (isAdd)
1518     Binary |= (1 << 8);
1519   Binary |= (Reg << 9);
1520   return Binary;
1521 }
1522 
1523 unsigned ARMMCCodeEmitter::getModImmOpValue(const MCInst &MI, unsigned Op,
1524                                             SmallVectorImpl<MCFixup> &Fixups,
1525                                             const MCSubtargetInfo &ST) const {
1526   const MCOperand &MO = MI.getOperand(Op);
1527 
1528   // Support for fixups (MCFixup)
1529   if (MO.isExpr()) {
1530     const MCExpr *Expr = MO.getExpr();
1531     // Fixups resolve to plain values that need to be encoded.
1532     MCFixupKind Kind = ARM::fixup_arm_mod_imm;
1533     addFixup(Fixups, 0, Expr, Kind);
1534     return 0;
1535   }
1536 
1537   // Immediate is already in its encoded format
1538   return MO.getImm();
1539 }
1540 
1541 unsigned ARMMCCodeEmitter::getT2SOImmOpValue(const MCInst &MI, unsigned Op,
1542                                              SmallVectorImpl<MCFixup> &Fixups,
1543                                              const MCSubtargetInfo &STI) const {
1544   const MCOperand &MO = MI.getOperand(Op);
1545 
1546   // Support for fixups (MCFixup)
1547   if (MO.isExpr()) {
1548     const MCExpr *Expr = MO.getExpr();
1549     // Fixups resolve to plain values that need to be encoded.
1550     MCFixupKind Kind = ARM::fixup_t2_so_imm;
1551     addFixup(Fixups, 0, Expr, Kind);
1552     return 0;
1553   }
1554   unsigned SoImm = MO.getImm();
1555   unsigned Encoded = ARM_AM::getT2SOImmVal(SoImm);
1556   assert(Encoded != ~0U && "Not a Thumb2 so_imm value?");
1557   return Encoded;
1558 }
1559 
1560 unsigned ARMMCCodeEmitter::
1561 getSORegRegOpValue(const MCInst &MI, unsigned OpIdx,
1562                 SmallVectorImpl<MCFixup> &Fixups,
1563                 const MCSubtargetInfo &STI) const {
1564   // Sub-operands are [reg, reg, imm]. The first register is Rm, the reg to be
1565   // shifted. The second is Rs, the amount to shift by, and the third specifies
1566   // the type of the shift.
1567   //
1568   // {3-0} = Rm.
1569   // {4}   = 1
1570   // {6-5} = type
1571   // {11-8} = Rs
1572   // {7}    = 0
1573 
1574   const MCOperand &MO  = MI.getOperand(OpIdx);
1575   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1576   const MCOperand &MO2 = MI.getOperand(OpIdx + 2);
1577   ARM_AM::ShiftOpc SOpc = ARM_AM::getSORegShOp(MO2.getImm());
1578 
1579   // Encode Rm.
1580   unsigned Binary = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1581 
1582   // Encode the shift opcode.
1583   unsigned SBits = 0;
1584   MCRegister Rs = MO1.getReg();
1585   if (Rs) {
1586     // Set shift operand (bit[7:4]).
1587     // LSL - 0001
1588     // LSR - 0011
1589     // ASR - 0101
1590     // ROR - 0111
1591     switch (SOpc) {
1592     default: llvm_unreachable("Unknown shift opc!");
1593     case ARM_AM::lsl: SBits = 0x1; break;
1594     case ARM_AM::lsr: SBits = 0x3; break;
1595     case ARM_AM::asr: SBits = 0x5; break;
1596     case ARM_AM::ror: SBits = 0x7; break;
1597     }
1598   }
1599 
1600   Binary |= SBits << 4;
1601 
1602   // Encode the shift operation Rs.
1603   // Encode Rs bit[11:8].
1604   assert(ARM_AM::getSORegOffset(MO2.getImm()) == 0);
1605   return Binary | (CTX.getRegisterInfo()->getEncodingValue(Rs) << ARMII::RegRsShift);
1606 }
1607 
1608 unsigned ARMMCCodeEmitter::
1609 getSORegImmOpValue(const MCInst &MI, unsigned OpIdx,
1610                 SmallVectorImpl<MCFixup> &Fixups,
1611                 const MCSubtargetInfo &STI) const {
1612   // Sub-operands are [reg, imm]. The first register is Rm, the reg to be
1613   // shifted. The second is the amount to shift by.
1614   //
1615   // {3-0} = Rm.
1616   // {4}   = 0
1617   // {6-5} = type
1618   // {11-7} = imm
1619 
1620   const MCOperand &MO  = MI.getOperand(OpIdx);
1621   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1622   ARM_AM::ShiftOpc SOpc = ARM_AM::getSORegShOp(MO1.getImm());
1623 
1624   // Encode Rm.
1625   unsigned Binary = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1626 
1627   // Encode the shift opcode.
1628   unsigned SBits = 0;
1629 
1630   // Set shift operand (bit[6:4]).
1631   // LSL - 000
1632   // LSR - 010
1633   // ASR - 100
1634   // ROR - 110
1635   // RRX - 110 and bit[11:8] clear.
1636   switch (SOpc) {
1637   default: llvm_unreachable("Unknown shift opc!");
1638   case ARM_AM::lsl: SBits = 0x0; break;
1639   case ARM_AM::lsr: SBits = 0x2; break;
1640   case ARM_AM::asr: SBits = 0x4; break;
1641   case ARM_AM::ror: SBits = 0x6; break;
1642   case ARM_AM::rrx:
1643     Binary |= 0x60;
1644     return Binary;
1645   }
1646 
1647   // Encode shift_imm bit[11:7].
1648   Binary |= SBits << 4;
1649   unsigned Offset = ARM_AM::getSORegOffset(MO1.getImm());
1650   assert(Offset < 32 && "Offset must be in range 0-31!");
1651   return Binary | (Offset << 7);
1652 }
1653 
1654 
1655 unsigned ARMMCCodeEmitter::
1656 getT2AddrModeSORegOpValue(const MCInst &MI, unsigned OpNum,
1657                 SmallVectorImpl<MCFixup> &Fixups,
1658                 const MCSubtargetInfo &STI) const {
1659   const MCOperand &MO1 = MI.getOperand(OpNum);
1660   const MCOperand &MO2 = MI.getOperand(OpNum+1);
1661   const MCOperand &MO3 = MI.getOperand(OpNum+2);
1662 
1663   // Encoded as [Rn, Rm, imm].
1664   // FIXME: Needs fixup support.
1665   unsigned Value = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
1666   Value <<= 4;
1667   Value |= CTX.getRegisterInfo()->getEncodingValue(MO2.getReg());
1668   Value <<= 2;
1669   Value |= MO3.getImm();
1670 
1671   return Value;
1672 }
1673 
1674 template<unsigned Bits, unsigned Shift>
1675 unsigned ARMMCCodeEmitter::
1676 getT2AddrModeImmOpValue(const MCInst &MI, unsigned OpNum,
1677                         SmallVectorImpl<MCFixup> &Fixups,
1678                         const MCSubtargetInfo &STI) const {
1679   const MCOperand &MO1 = MI.getOperand(OpNum);
1680   const MCOperand &MO2 = MI.getOperand(OpNum+1);
1681 
1682   // FIXME: Needs fixup support.
1683   unsigned Value = CTX.getRegisterInfo()->getEncodingValue(MO1.getReg());
1684 
1685   // If the immediate is B bits long, we need B+1 bits in order
1686   // to represent the (inverse of the) sign bit.
1687   Value <<= (Bits + 1);
1688   int32_t tmp = (int32_t)MO2.getImm();
1689   if (tmp == INT32_MIN) { // represents subtracting zero rather than adding it
1690     tmp = 0;
1691   } else if (tmp < 0) {
1692     tmp = abs(tmp);
1693   } else {
1694     Value |= (1U << Bits); // Set the ADD bit
1695   }
1696   Value |= (tmp >> Shift) & ((1U << Bits) - 1);
1697   return Value;
1698 }
1699 
1700 unsigned ARMMCCodeEmitter::
1701 getT2AddrModeImm8OffsetOpValue(const MCInst &MI, unsigned OpNum,
1702                          SmallVectorImpl<MCFixup> &Fixups,
1703                          const MCSubtargetInfo &STI) const {
1704   const MCOperand &MO1 = MI.getOperand(OpNum);
1705 
1706   // FIXME: Needs fixup support.
1707   unsigned Value = 0;
1708   auto tmp = static_cast<uint32_t>(MO1.getImm());
1709   if (static_cast<int32_t>(tmp) < 0)
1710     tmp = -tmp;
1711   else
1712     Value |= 256; // Set the ADD bit
1713   Value |= tmp & 255;
1714   return Value;
1715 }
1716 
1717 unsigned ARMMCCodeEmitter::
1718 getT2SORegOpValue(const MCInst &MI, unsigned OpIdx,
1719                 SmallVectorImpl<MCFixup> &Fixups,
1720                 const MCSubtargetInfo &STI) const {
1721   // Sub-operands are [reg, imm]. The first register is Rm, the reg to be
1722   // shifted. The second is the amount to shift by.
1723   //
1724   // {3-0} = Rm.
1725   // {4}   = 0
1726   // {6-5} = type
1727   // {11-7} = imm
1728 
1729   const MCOperand &MO  = MI.getOperand(OpIdx);
1730   const MCOperand &MO1 = MI.getOperand(OpIdx + 1);
1731   ARM_AM::ShiftOpc SOpc = ARM_AM::getSORegShOp(MO1.getImm());
1732 
1733   // Encode Rm.
1734   unsigned Binary = CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1735 
1736   // Encode the shift opcode.
1737   unsigned SBits = 0;
1738   // Set shift operand (bit[6:4]).
1739   // LSL - 000
1740   // LSR - 010
1741   // ASR - 100
1742   // ROR - 110
1743   switch (SOpc) {
1744   default: llvm_unreachable("Unknown shift opc!");
1745   case ARM_AM::lsl: SBits = 0x0; break;
1746   case ARM_AM::lsr: SBits = 0x2; break;
1747   case ARM_AM::asr: SBits = 0x4; break;
1748   case ARM_AM::rrx: [[fallthrough]];
1749   case ARM_AM::ror: SBits = 0x6; break;
1750   }
1751 
1752   Binary |= SBits << 4;
1753   if (SOpc == ARM_AM::rrx)
1754     return Binary;
1755 
1756   // Encode shift_imm bit[11:7].
1757   return Binary | ARM_AM::getSORegOffset(MO1.getImm()) << 7;
1758 }
1759 
1760 unsigned ARMMCCodeEmitter::
1761 getBitfieldInvertedMaskOpValue(const MCInst &MI, unsigned Op,
1762                                SmallVectorImpl<MCFixup> &Fixups,
1763                                const MCSubtargetInfo &STI) const {
1764   // 10 bits. lower 5 bits are the lsb of the mask, high five bits are the
1765   // msb of the mask.
1766   const MCOperand &MO = MI.getOperand(Op);
1767   uint32_t v = ~MO.getImm();
1768   uint32_t lsb = llvm::countr_zero(v);
1769   uint32_t msb = llvm::Log2_32(v);
1770   assert(v != 0 && lsb < 32 && msb < 32 && "Illegal bitfield mask!");
1771   return lsb | (msb << 5);
1772 }
1773 
1774 unsigned ARMMCCodeEmitter::
1775 getRegisterListOpValue(const MCInst &MI, unsigned Op,
1776                        SmallVectorImpl<MCFixup> &Fixups,
1777                        const MCSubtargetInfo &STI) const {
1778   // VLDM/VSTM/VSCCLRM:
1779   //   {12-8} = Vd
1780   //   {7-0}  = Number of registers
1781   //
1782   // LDM/STM:
1783   //   {15-0}  = Bitfield of GPRs.
1784   MCRegister Reg = MI.getOperand(Op).getReg();
1785   bool SPRRegs = ARMMCRegisterClasses[ARM::SPRRegClassID].contains(Reg);
1786   bool DPRRegs = ARMMCRegisterClasses[ARM::DPRRegClassID].contains(Reg);
1787 
1788   unsigned Binary = 0;
1789 
1790   if (SPRRegs || DPRRegs || Reg == ARM::VPR) {
1791     // VLDM/VSTM/VSCCLRM
1792     unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(Reg);
1793     unsigned NumRegs = (MI.getNumOperands() - Op) & 0xff;
1794     Binary |= (RegNo & 0x1f) << 8;
1795 
1796     if (MI.getOpcode() == ARM::VSCCLRMD)
1797       // Ignore VPR
1798       --NumRegs;
1799     else if (MI.getOpcode() == ARM::VSCCLRMS) {
1800       // The register list can contain both S registers and D registers, with D
1801       // registers counting as two registers. VPR doesn't count towards the
1802       // number of registers.
1803       NumRegs = 0;
1804       for (unsigned I = Op, E = MI.getNumOperands(); I < E; ++I) {
1805         Reg = MI.getOperand(I).getReg();
1806         if (ARMMCRegisterClasses[ARM::SPRRegClassID].contains(Reg))
1807           NumRegs += 1;
1808         else if (ARMMCRegisterClasses[ARM::DPRRegClassID].contains(Reg))
1809           NumRegs += 2;
1810       }
1811     }
1812     if (SPRRegs)
1813       Binary |= NumRegs;
1814     else
1815       Binary |= NumRegs * 2;
1816   } else {
1817     const MCRegisterInfo &MRI = *CTX.getRegisterInfo();
1818     assert(is_sorted(drop_begin(MI, Op),
1819                      [&](const MCOperand &LHS, const MCOperand &RHS) {
1820                        return MRI.getEncodingValue(LHS.getReg()) <
1821                               MRI.getEncodingValue(RHS.getReg());
1822                      }));
1823     for (unsigned I = Op, E = MI.getNumOperands(); I < E; ++I) {
1824       unsigned RegNo = MRI.getEncodingValue(MI.getOperand(I).getReg());
1825       Binary |= 1 << RegNo;
1826     }
1827   }
1828 
1829   return Binary;
1830 }
1831 
1832 /// getAddrMode6AddressOpValue - Encode an addrmode6 register number along
1833 /// with the alignment operand.
1834 unsigned ARMMCCodeEmitter::
1835 getAddrMode6AddressOpValue(const MCInst &MI, unsigned Op,
1836                            SmallVectorImpl<MCFixup> &Fixups,
1837                            const MCSubtargetInfo &STI) const {
1838   const MCOperand &Reg = MI.getOperand(Op);
1839   const MCOperand &Imm = MI.getOperand(Op + 1);
1840 
1841   unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(Reg.getReg());
1842   unsigned Align = 0;
1843 
1844   switch (Imm.getImm()) {
1845   default: break;
1846   case 2:
1847   case 4:
1848   case 8:  Align = 0x01; break;
1849   case 16: Align = 0x02; break;
1850   case 32: Align = 0x03; break;
1851   }
1852 
1853   return RegNo | (Align << 4);
1854 }
1855 
1856 /// getAddrMode6OneLane32AddressOpValue - Encode an addrmode6 register number
1857 /// along  with the alignment operand for use in VST1 and VLD1 with size 32.
1858 unsigned ARMMCCodeEmitter::
1859 getAddrMode6OneLane32AddressOpValue(const MCInst &MI, unsigned Op,
1860                                     SmallVectorImpl<MCFixup> &Fixups,
1861                                     const MCSubtargetInfo &STI) const {
1862   const MCOperand &Reg = MI.getOperand(Op);
1863   const MCOperand &Imm = MI.getOperand(Op + 1);
1864 
1865   unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(Reg.getReg());
1866   unsigned Align = 0;
1867 
1868   switch (Imm.getImm()) {
1869   default: break;
1870   case 8:
1871   case 16:
1872   case 32: // Default '0' value for invalid alignments of 8, 16, 32 bytes.
1873   case 2: Align = 0x00; break;
1874   case 4: Align = 0x03; break;
1875   }
1876 
1877   return RegNo | (Align << 4);
1878 }
1879 
1880 
1881 /// getAddrMode6DupAddressOpValue - Encode an addrmode6 register number and
1882 /// alignment operand for use in VLD-dup instructions.  This is the same as
1883 /// getAddrMode6AddressOpValue except for the alignment encoding, which is
1884 /// different for VLD4-dup.
1885 unsigned ARMMCCodeEmitter::
1886 getAddrMode6DupAddressOpValue(const MCInst &MI, unsigned Op,
1887                               SmallVectorImpl<MCFixup> &Fixups,
1888                               const MCSubtargetInfo &STI) const {
1889   const MCOperand &Reg = MI.getOperand(Op);
1890   const MCOperand &Imm = MI.getOperand(Op + 1);
1891 
1892   unsigned RegNo = CTX.getRegisterInfo()->getEncodingValue(Reg.getReg());
1893   unsigned Align = 0;
1894 
1895   switch (Imm.getImm()) {
1896   default: break;
1897   case 2:
1898   case 4:
1899   case 8:  Align = 0x01; break;
1900   case 16: Align = 0x03; break;
1901   }
1902 
1903   return RegNo | (Align << 4);
1904 }
1905 
1906 unsigned ARMMCCodeEmitter::
1907 getAddrMode6OffsetOpValue(const MCInst &MI, unsigned Op,
1908                           SmallVectorImpl<MCFixup> &Fixups,
1909                           const MCSubtargetInfo &STI) const {
1910   const MCOperand &MO = MI.getOperand(Op);
1911   if (!MO.getReg())
1912     return 0x0D;
1913   return CTX.getRegisterInfo()->getEncodingValue(MO.getReg());
1914 }
1915 
1916 unsigned ARMMCCodeEmitter::
1917 getShiftRight8Imm(const MCInst &MI, unsigned Op,
1918                   SmallVectorImpl<MCFixup> &Fixups,
1919                   const MCSubtargetInfo &STI) const {
1920   return 8 - MI.getOperand(Op).getImm();
1921 }
1922 
1923 unsigned ARMMCCodeEmitter::
1924 getShiftRight16Imm(const MCInst &MI, unsigned Op,
1925                    SmallVectorImpl<MCFixup> &Fixups,
1926                    const MCSubtargetInfo &STI) const {
1927   return 16 - MI.getOperand(Op).getImm();
1928 }
1929 
1930 unsigned ARMMCCodeEmitter::
1931 getShiftRight32Imm(const MCInst &MI, unsigned Op,
1932                    SmallVectorImpl<MCFixup> &Fixups,
1933                    const MCSubtargetInfo &STI) const {
1934   return 32 - MI.getOperand(Op).getImm();
1935 }
1936 
1937 unsigned ARMMCCodeEmitter::
1938 getShiftRight64Imm(const MCInst &MI, unsigned Op,
1939                    SmallVectorImpl<MCFixup> &Fixups,
1940                    const MCSubtargetInfo &STI) const {
1941   return 64 - MI.getOperand(Op).getImm();
1942 }
1943 
1944 void ARMMCCodeEmitter::encodeInstruction(const MCInst &MI,
1945                                          SmallVectorImpl<char> &CB,
1946                                          SmallVectorImpl<MCFixup> &Fixups,
1947                                          const MCSubtargetInfo &STI) const {
1948   // Pseudo instructions don't get encoded.
1949   const MCInstrDesc &Desc = MCII.get(MI.getOpcode());
1950   uint64_t TSFlags = Desc.TSFlags;
1951   if ((TSFlags & ARMII::FormMask) == ARMII::Pseudo)
1952     return;
1953 
1954   int Size;
1955   if (Desc.getSize() == 2 || Desc.getSize() == 4)
1956     Size = Desc.getSize();
1957   else
1958     llvm_unreachable("Unexpected instruction size!");
1959 
1960   auto Endian =
1961       IsLittleEndian ? llvm::endianness::little : llvm::endianness::big;
1962   uint32_t Binary = getBinaryCodeForInstr(MI, Fixups, STI);
1963   if (Size == 2) {
1964     support::endian::write<uint16_t>(CB, Binary, Endian);
1965   } else if (isThumb(STI)) {
1966     // Thumb 32-bit wide instructions need to emit the high order halfword
1967     // first.
1968     support::endian::write<uint16_t>(CB, Binary >> 16, Endian);
1969     support::endian::write<uint16_t>(CB, Binary & 0xffff, Endian);
1970   } else {
1971     support::endian::write<uint32_t>(CB, Binary, Endian);
1972   }
1973   ++MCNumEmitted;  // Keep track of the # of mi's emitted.
1974 }
1975 
1976 template <bool isNeg, ARM::Fixups fixup>
1977 uint32_t
1978 ARMMCCodeEmitter::getBFTargetOpValue(const MCInst &MI, unsigned OpIdx,
1979                                      SmallVectorImpl<MCFixup> &Fixups,
1980                                      const MCSubtargetInfo &STI) const {
1981   const MCOperand MO = MI.getOperand(OpIdx);
1982   if (MO.isExpr())
1983     return ::getBranchTargetOpValue(MI, OpIdx, fixup, Fixups, STI);
1984   return isNeg ? -(MO.getImm() >> 1) : (MO.getImm() >> 1);
1985 }
1986 
1987 uint32_t
1988 ARMMCCodeEmitter::getBFAfterTargetOpValue(const MCInst &MI, unsigned OpIdx,
1989                                           SmallVectorImpl<MCFixup> &Fixups,
1990                                           const MCSubtargetInfo &STI) const {
1991   const MCOperand MO = MI.getOperand(OpIdx);
1992   const MCOperand BranchMO = MI.getOperand(0);
1993 
1994   if (MO.isExpr()) {
1995     assert(BranchMO.isExpr());
1996     const MCExpr *DiffExpr = MCBinaryExpr::createSub(
1997         MO.getExpr(), BranchMO.getExpr(), CTX);
1998     MCFixupKind Kind = ARM::fixup_bfcsel_else_target;
1999     addFixup(Fixups, 0, DiffExpr, Kind);
2000     return 0;
2001   }
2002 
2003   assert(MO.isImm() && BranchMO.isImm());
2004   int Diff = MO.getImm() - BranchMO.getImm();
2005   assert(Diff == 4 || Diff == 2);
2006 
2007   return Diff == 4;
2008 }
2009 
2010 uint32_t ARMMCCodeEmitter::getVPTMaskOpValue(const MCInst &MI, unsigned OpIdx,
2011                                              SmallVectorImpl<MCFixup> &Fixups,
2012                                              const MCSubtargetInfo &STI)const {
2013   const MCOperand MO = MI.getOperand(OpIdx);
2014   assert(MO.isImm() && "Unexpected operand type!");
2015 
2016   int Value = MO.getImm();
2017   int Imm = 0;
2018 
2019   // VPT Masks are actually encoded as a series of invert/don't invert bits,
2020   // rather than true/false bits.
2021   unsigned PrevBit = 0;
2022   for (int i = 3; i >= 0; --i) {
2023     unsigned Bit = (Value >> i) & 1;
2024 
2025     // Check if we are at the end of the mask.
2026     if ((Value & ~(~0U << i)) == 0) {
2027       Imm |= (1 << i);
2028       break;
2029     }
2030 
2031     // Convert the bit in the mask based on the previous bit.
2032     if (Bit != PrevBit)
2033       Imm |= (1 << i);
2034 
2035     PrevBit = Bit;
2036   }
2037 
2038   return Imm;
2039 }
2040 
2041 uint32_t ARMMCCodeEmitter::getRestrictedCondCodeOpValue(
2042     const MCInst &MI, unsigned OpIdx, SmallVectorImpl<MCFixup> &Fixups,
2043     const MCSubtargetInfo &STI) const {
2044 
2045   const MCOperand MO = MI.getOperand(OpIdx);
2046   assert(MO.isImm() && "Unexpected operand type!");
2047 
2048   switch (MO.getImm()) {
2049   default:
2050     assert(0 && "Unexpected Condition!");
2051     return 0;
2052   case ARMCC::HS:
2053   case ARMCC::EQ:
2054     return 0;
2055   case ARMCC::HI:
2056   case ARMCC::NE:
2057     return 1;
2058   case ARMCC::GE:
2059     return 4;
2060   case ARMCC::LT:
2061     return 5;
2062   case ARMCC::GT:
2063     return 6;
2064   case ARMCC::LE:
2065     return 7;
2066   }
2067 }
2068 
2069 uint32_t ARMMCCodeEmitter::
2070 getPowerTwoOpValue(const MCInst &MI, unsigned OpIdx,
2071                    SmallVectorImpl<MCFixup> &Fixups,
2072                    const MCSubtargetInfo &STI) const {
2073   const MCOperand &MO = MI.getOperand(OpIdx);
2074   assert(MO.isImm() && "Unexpected operand type!");
2075   return llvm::countr_zero((uint64_t)MO.getImm());
2076 }
2077 
2078 template <unsigned start>
2079 uint32_t ARMMCCodeEmitter::
2080 getMVEPairVectorIndexOpValue(const MCInst &MI, unsigned OpIdx,
2081                              SmallVectorImpl<MCFixup> &Fixups,
2082                              const MCSubtargetInfo &STI) const {
2083   const MCOperand MO = MI.getOperand(OpIdx);
2084   assert(MO.isImm() && "Unexpected operand type!");
2085 
2086   int Value = MO.getImm();
2087   return Value - start;
2088 }
2089 
2090 #include "ARMGenMCCodeEmitter.inc"
2091 
2092 MCCodeEmitter *llvm::createARMLEMCCodeEmitter(const MCInstrInfo &MCII,
2093                                               MCContext &Ctx) {
2094   return new ARMMCCodeEmitter(MCII, Ctx, true);
2095 }
2096 
2097 MCCodeEmitter *llvm::createARMBEMCCodeEmitter(const MCInstrInfo &MCII,
2098                                               MCContext &Ctx) {
2099   return new ARMMCCodeEmitter(MCII, Ctx, false);
2100 }
2101