1 //===-- RISCVAsmParser.cpp - Parse RISCV assembly to MCInst instructions --===//
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 #include "MCTargetDesc/RISCVAsmBackend.h"
10 #include "MCTargetDesc/RISCVInstPrinter.h"
11 #include "MCTargetDesc/RISCVMCExpr.h"
12 #include "MCTargetDesc/RISCVMCTargetDesc.h"
13 #include "MCTargetDesc/RISCVTargetStreamer.h"
14 #include "TargetInfo/RISCVTargetInfo.h"
15 #include "Utils/RISCVBaseInfo.h"
16 #include "Utils/RISCVMatInt.h"
17 #include "llvm/ADT/STLExtras.h"
18 #include "llvm/ADT/SmallBitVector.h"
19 #include "llvm/ADT/SmallString.h"
20 #include "llvm/ADT/SmallVector.h"
21 #include "llvm/ADT/Statistic.h"
22 #include "llvm/ADT/StringSwitch.h"
23 #include "llvm/MC/MCAssembler.h"
24 #include "llvm/MC/MCContext.h"
25 #include "llvm/MC/MCExpr.h"
26 #include "llvm/MC/MCInst.h"
27 #include "llvm/MC/MCInstBuilder.h"
28 #include "llvm/MC/MCObjectFileInfo.h"
29 #include "llvm/MC/MCParser/MCAsmLexer.h"
30 #include "llvm/MC/MCParser/MCParsedAsmOperand.h"
31 #include "llvm/MC/MCParser/MCTargetAsmParser.h"
32 #include "llvm/MC/MCRegisterInfo.h"
33 #include "llvm/MC/MCStreamer.h"
34 #include "llvm/MC/MCSubtargetInfo.h"
35 #include "llvm/MC/MCValue.h"
36 #include "llvm/Support/Casting.h"
37 #include "llvm/Support/MathExtras.h"
38 #include "llvm/Support/RISCVAttributes.h"
39 #include "llvm/Support/TargetRegistry.h"
40 
41 #include <limits>
42 
43 using namespace llvm;
44 
45 #define DEBUG_TYPE "riscv-asm-parser"
46 
47 // Include the auto-generated portion of the compress emitter.
48 #define GEN_COMPRESS_INSTR
49 #include "RISCVGenCompressInstEmitter.inc"
50 
51 STATISTIC(RISCVNumInstrsCompressed,
52           "Number of RISC-V Compressed instructions emitted");
53 
54 namespace {
55 struct RISCVOperand;
56 
57 struct ParserOptionsSet {
58   bool IsPicEnabled;
59 };
60 
61 class RISCVAsmParser : public MCTargetAsmParser {
62   SmallVector<FeatureBitset, 4> FeatureBitStack;
63 
64   SmallVector<ParserOptionsSet, 4> ParserOptionsStack;
65   ParserOptionsSet ParserOptions;
66 
67   SMLoc getLoc() const { return getParser().getTok().getLoc(); }
68   bool isRV64() const { return getSTI().hasFeature(RISCV::Feature64Bit); }
69   bool isRV32E() const { return getSTI().hasFeature(RISCV::FeatureRV32E); }
70 
71   RISCVTargetStreamer &getTargetStreamer() {
72     MCTargetStreamer &TS = *getParser().getStreamer().getTargetStreamer();
73     return static_cast<RISCVTargetStreamer &>(TS);
74   }
75 
76   unsigned validateTargetOperandClass(MCParsedAsmOperand &Op,
77                                       unsigned Kind) override;
78 
79   bool generateImmOutOfRangeError(OperandVector &Operands, uint64_t ErrorInfo,
80                                   int64_t Lower, int64_t Upper, Twine Msg);
81 
82   bool MatchAndEmitInstruction(SMLoc IDLoc, unsigned &Opcode,
83                                OperandVector &Operands, MCStreamer &Out,
84                                uint64_t &ErrorInfo,
85                                bool MatchingInlineAsm) override;
86 
87   bool ParseRegister(unsigned &RegNo, SMLoc &StartLoc, SMLoc &EndLoc) override;
88   OperandMatchResultTy tryParseRegister(unsigned &RegNo, SMLoc &StartLoc,
89                                         SMLoc &EndLoc) override;
90 
91   bool ParseInstruction(ParseInstructionInfo &Info, StringRef Name,
92                         SMLoc NameLoc, OperandVector &Operands) override;
93 
94   bool ParseDirective(AsmToken DirectiveID) override;
95 
96   // Helper to actually emit an instruction to the MCStreamer. Also, when
97   // possible, compression of the instruction is performed.
98   void emitToStreamer(MCStreamer &S, const MCInst &Inst);
99 
100   // Helper to emit a combination of LUI, ADDI(W), and SLLI instructions that
101   // synthesize the desired immedate value into the destination register.
102   void emitLoadImm(MCRegister DestReg, int64_t Value, MCStreamer &Out);
103 
104   // Helper to emit a combination of AUIPC and SecondOpcode. Used to implement
105   // helpers such as emitLoadLocalAddress and emitLoadAddress.
106   void emitAuipcInstPair(MCOperand DestReg, MCOperand TmpReg,
107                          const MCExpr *Symbol, RISCVMCExpr::VariantKind VKHi,
108                          unsigned SecondOpcode, SMLoc IDLoc, MCStreamer &Out);
109 
110   // Helper to emit pseudo instruction "lla" used in PC-rel addressing.
111   void emitLoadLocalAddress(MCInst &Inst, SMLoc IDLoc, MCStreamer &Out);
112 
113   // Helper to emit pseudo instruction "la" used in GOT/PC-rel addressing.
114   void emitLoadAddress(MCInst &Inst, SMLoc IDLoc, MCStreamer &Out);
115 
116   // Helper to emit pseudo instruction "la.tls.ie" used in initial-exec TLS
117   // addressing.
118   void emitLoadTLSIEAddress(MCInst &Inst, SMLoc IDLoc, MCStreamer &Out);
119 
120   // Helper to emit pseudo instruction "la.tls.gd" used in global-dynamic TLS
121   // addressing.
122   void emitLoadTLSGDAddress(MCInst &Inst, SMLoc IDLoc, MCStreamer &Out);
123 
124   // Helper to emit pseudo load/store instruction with a symbol.
125   void emitLoadStoreSymbol(MCInst &Inst, unsigned Opcode, SMLoc IDLoc,
126                            MCStreamer &Out, bool HasTmpReg);
127 
128   // Helper to emit pseudo sign/zero extend instruction.
129   void emitPseudoExtend(MCInst &Inst, bool SignExtend, int64_t Width,
130                         SMLoc IDLoc, MCStreamer &Out);
131 
132   // Checks that a PseudoAddTPRel is using x4/tp in its second input operand.
133   // Enforcing this using a restricted register class for the second input
134   // operand of PseudoAddTPRel results in a poor diagnostic due to the fact
135   // 'add' is an overloaded mnemonic.
136   bool checkPseudoAddTPRel(MCInst &Inst, OperandVector &Operands);
137 
138   // Check instruction constraints.
139   bool validateInstruction(MCInst &Inst, OperandVector &Operands);
140 
141   /// Helper for processing MC instructions that have been successfully matched
142   /// by MatchAndEmitInstruction. Modifications to the emitted instructions,
143   /// like the expansion of pseudo instructions (e.g., "li"), can be performed
144   /// in this method.
145   bool processInstruction(MCInst &Inst, SMLoc IDLoc, OperandVector &Operands,
146                           MCStreamer &Out);
147 
148 // Auto-generated instruction matching functions
149 #define GET_ASSEMBLER_HEADER
150 #include "RISCVGenAsmMatcher.inc"
151 
152   OperandMatchResultTy parseCSRSystemRegister(OperandVector &Operands);
153   OperandMatchResultTy parseImmediate(OperandVector &Operands);
154   OperandMatchResultTy parseRegister(OperandVector &Operands,
155                                      bool AllowParens = false);
156   OperandMatchResultTy parseMemOpBaseReg(OperandVector &Operands);
157   OperandMatchResultTy parseAtomicMemOp(OperandVector &Operands);
158   OperandMatchResultTy parseOperandWithModifier(OperandVector &Operands);
159   OperandMatchResultTy parseBareSymbol(OperandVector &Operands);
160   OperandMatchResultTy parseCallSymbol(OperandVector &Operands);
161   OperandMatchResultTy parsePseudoJumpSymbol(OperandVector &Operands);
162   OperandMatchResultTy parseJALOffset(OperandVector &Operands);
163   OperandMatchResultTy parseVTypeI(OperandVector &Operands);
164   OperandMatchResultTy parseMaskReg(OperandVector &Operands);
165 
166   bool parseOperand(OperandVector &Operands, StringRef Mnemonic);
167 
168   bool parseDirectiveOption();
169   bool parseDirectiveAttribute();
170 
171   void setFeatureBits(uint64_t Feature, StringRef FeatureString) {
172     if (!(getSTI().getFeatureBits()[Feature])) {
173       MCSubtargetInfo &STI = copySTI();
174       setAvailableFeatures(
175           ComputeAvailableFeatures(STI.ToggleFeature(FeatureString)));
176     }
177   }
178 
179   bool getFeatureBits(uint64_t Feature) {
180     return getSTI().getFeatureBits()[Feature];
181   }
182 
183   void clearFeatureBits(uint64_t Feature, StringRef FeatureString) {
184     if (getSTI().getFeatureBits()[Feature]) {
185       MCSubtargetInfo &STI = copySTI();
186       setAvailableFeatures(
187           ComputeAvailableFeatures(STI.ToggleFeature(FeatureString)));
188     }
189   }
190 
191   void pushFeatureBits() {
192     assert(FeatureBitStack.size() == ParserOptionsStack.size() &&
193            "These two stacks must be kept synchronized");
194     FeatureBitStack.push_back(getSTI().getFeatureBits());
195     ParserOptionsStack.push_back(ParserOptions);
196   }
197 
198   bool popFeatureBits() {
199     assert(FeatureBitStack.size() == ParserOptionsStack.size() &&
200            "These two stacks must be kept synchronized");
201     if (FeatureBitStack.empty())
202       return true;
203 
204     FeatureBitset FeatureBits = FeatureBitStack.pop_back_val();
205     copySTI().setFeatureBits(FeatureBits);
206     setAvailableFeatures(ComputeAvailableFeatures(FeatureBits));
207 
208     ParserOptions = ParserOptionsStack.pop_back_val();
209 
210     return false;
211   }
212 
213   std::unique_ptr<RISCVOperand> defaultMaskRegOp() const;
214 
215 public:
216   enum RISCVMatchResultTy {
217     Match_Dummy = FIRST_TARGET_MATCH_RESULT_TY,
218 #define GET_OPERAND_DIAGNOSTIC_TYPES
219 #include "RISCVGenAsmMatcher.inc"
220 #undef GET_OPERAND_DIAGNOSTIC_TYPES
221   };
222 
223   static bool classifySymbolRef(const MCExpr *Expr,
224                                 RISCVMCExpr::VariantKind &Kind);
225 
226   RISCVAsmParser(const MCSubtargetInfo &STI, MCAsmParser &Parser,
227                  const MCInstrInfo &MII, const MCTargetOptions &Options)
228       : MCTargetAsmParser(Options, STI, MII) {
229     Parser.addAliasForDirective(".half", ".2byte");
230     Parser.addAliasForDirective(".hword", ".2byte");
231     Parser.addAliasForDirective(".word", ".4byte");
232     Parser.addAliasForDirective(".dword", ".8byte");
233     setAvailableFeatures(ComputeAvailableFeatures(STI.getFeatureBits()));
234 
235     auto ABIName = StringRef(Options.ABIName);
236     if (ABIName.endswith("f") &&
237         !getSTI().getFeatureBits()[RISCV::FeatureStdExtF]) {
238       errs() << "Hard-float 'f' ABI can't be used for a target that "
239                 "doesn't support the F instruction set extension (ignoring "
240                 "target-abi)\n";
241     } else if (ABIName.endswith("d") &&
242                !getSTI().getFeatureBits()[RISCV::FeatureStdExtD]) {
243       errs() << "Hard-float 'd' ABI can't be used for a target that "
244                 "doesn't support the D instruction set extension (ignoring "
245                 "target-abi)\n";
246     }
247 
248     const MCObjectFileInfo *MOFI = Parser.getContext().getObjectFileInfo();
249     ParserOptions.IsPicEnabled = MOFI->isPositionIndependent();
250   }
251 };
252 
253 /// RISCVOperand - Instances of this class represent a parsed machine
254 /// instruction
255 struct RISCVOperand : public MCParsedAsmOperand {
256 
257   enum class KindTy {
258     Token,
259     Register,
260     Immediate,
261     SystemRegister,
262     VType,
263   } Kind;
264 
265   bool IsRV64;
266 
267   struct RegOp {
268     MCRegister RegNum;
269   };
270 
271   struct ImmOp {
272     const MCExpr *Val;
273   };
274 
275   struct SysRegOp {
276     const char *Data;
277     unsigned Length;
278     unsigned Encoding;
279     // FIXME: Add the Encoding parsed fields as needed for checks,
280     // e.g.: read/write or user/supervisor/machine privileges.
281   };
282 
283   struct VTypeOp {
284     unsigned Val;
285   };
286 
287   SMLoc StartLoc, EndLoc;
288   union {
289     StringRef Tok;
290     RegOp Reg;
291     ImmOp Imm;
292     struct SysRegOp SysReg;
293     struct VTypeOp VType;
294   };
295 
296   RISCVOperand(KindTy K) : MCParsedAsmOperand(), Kind(K) {}
297 
298 public:
299   RISCVOperand(const RISCVOperand &o) : MCParsedAsmOperand() {
300     Kind = o.Kind;
301     IsRV64 = o.IsRV64;
302     StartLoc = o.StartLoc;
303     EndLoc = o.EndLoc;
304     switch (Kind) {
305     case KindTy::Register:
306       Reg = o.Reg;
307       break;
308     case KindTy::Immediate:
309       Imm = o.Imm;
310       break;
311     case KindTy::Token:
312       Tok = o.Tok;
313       break;
314     case KindTy::SystemRegister:
315       SysReg = o.SysReg;
316       break;
317     case KindTy::VType:
318       VType = o.VType;
319       break;
320     }
321   }
322 
323   bool isToken() const override { return Kind == KindTy::Token; }
324   bool isReg() const override { return Kind == KindTy::Register; }
325   bool isV0Reg() const {
326     return Kind == KindTy::Register && Reg.RegNum == RISCV::V0;
327   }
328   bool isImm() const override { return Kind == KindTy::Immediate; }
329   bool isMem() const override { return false; }
330   bool isSystemRegister() const { return Kind == KindTy::SystemRegister; }
331   bool isVType() const { return Kind == KindTy::VType; }
332 
333   bool isGPR() const {
334     return Kind == KindTy::Register &&
335            RISCVMCRegisterClasses[RISCV::GPRRegClassID].contains(Reg.RegNum);
336   }
337 
338   static bool evaluateConstantImm(const MCExpr *Expr, int64_t &Imm,
339                                   RISCVMCExpr::VariantKind &VK) {
340     if (auto *RE = dyn_cast<RISCVMCExpr>(Expr)) {
341       VK = RE->getKind();
342       return RE->evaluateAsConstant(Imm);
343     }
344 
345     if (auto CE = dyn_cast<MCConstantExpr>(Expr)) {
346       VK = RISCVMCExpr::VK_RISCV_None;
347       Imm = CE->getValue();
348       return true;
349     }
350 
351     return false;
352   }
353 
354   // True if operand is a symbol with no modifiers, or a constant with no
355   // modifiers and isShiftedInt<N-1, 1>(Op).
356   template <int N> bool isBareSimmNLsb0() const {
357     int64_t Imm;
358     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
359     if (!isImm())
360       return false;
361     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
362     bool IsValid;
363     if (!IsConstantImm)
364       IsValid = RISCVAsmParser::classifySymbolRef(getImm(), VK);
365     else
366       IsValid = isShiftedInt<N - 1, 1>(Imm);
367     return IsValid && VK == RISCVMCExpr::VK_RISCV_None;
368   }
369 
370   // Predicate methods for AsmOperands defined in RISCVInstrInfo.td
371 
372   bool isBareSymbol() const {
373     int64_t Imm;
374     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
375     // Must be of 'immediate' type but not a constant.
376     if (!isImm() || evaluateConstantImm(getImm(), Imm, VK))
377       return false;
378     return RISCVAsmParser::classifySymbolRef(getImm(), VK) &&
379            VK == RISCVMCExpr::VK_RISCV_None;
380   }
381 
382   bool isCallSymbol() const {
383     int64_t Imm;
384     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
385     // Must be of 'immediate' type but not a constant.
386     if (!isImm() || evaluateConstantImm(getImm(), Imm, VK))
387       return false;
388     return RISCVAsmParser::classifySymbolRef(getImm(), VK) &&
389            (VK == RISCVMCExpr::VK_RISCV_CALL ||
390             VK == RISCVMCExpr::VK_RISCV_CALL_PLT);
391   }
392 
393   bool isPseudoJumpSymbol() const {
394     int64_t Imm;
395     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
396     // Must be of 'immediate' type but not a constant.
397     if (!isImm() || evaluateConstantImm(getImm(), Imm, VK))
398       return false;
399     return RISCVAsmParser::classifySymbolRef(getImm(), VK) &&
400            VK == RISCVMCExpr::VK_RISCV_CALL;
401   }
402 
403   bool isTPRelAddSymbol() const {
404     int64_t Imm;
405     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
406     // Must be of 'immediate' type but not a constant.
407     if (!isImm() || evaluateConstantImm(getImm(), Imm, VK))
408       return false;
409     return RISCVAsmParser::classifySymbolRef(getImm(), VK) &&
410            VK == RISCVMCExpr::VK_RISCV_TPREL_ADD;
411   }
412 
413   bool isCSRSystemRegister() const { return isSystemRegister(); }
414 
415   bool isVTypeI() const { return isVType(); }
416 
417   /// Return true if the operand is a valid for the fence instruction e.g.
418   /// ('iorw').
419   bool isFenceArg() const {
420     if (!isImm())
421       return false;
422     const MCExpr *Val = getImm();
423     auto *SVal = dyn_cast<MCSymbolRefExpr>(Val);
424     if (!SVal || SVal->getKind() != MCSymbolRefExpr::VK_None)
425       return false;
426 
427     StringRef Str = SVal->getSymbol().getName();
428     // Letters must be unique, taken from 'iorw', and in ascending order. This
429     // holds as long as each individual character is one of 'iorw' and is
430     // greater than the previous character.
431     char Prev = '\0';
432     for (char c : Str) {
433       if (c != 'i' && c != 'o' && c != 'r' && c != 'w')
434         return false;
435       if (c <= Prev)
436         return false;
437       Prev = c;
438     }
439     return true;
440   }
441 
442   /// Return true if the operand is a valid floating point rounding mode.
443   bool isFRMArg() const {
444     if (!isImm())
445       return false;
446     const MCExpr *Val = getImm();
447     auto *SVal = dyn_cast<MCSymbolRefExpr>(Val);
448     if (!SVal || SVal->getKind() != MCSymbolRefExpr::VK_None)
449       return false;
450 
451     StringRef Str = SVal->getSymbol().getName();
452 
453     return RISCVFPRndMode::stringToRoundingMode(Str) != RISCVFPRndMode::Invalid;
454   }
455 
456   bool isImmXLenLI() const {
457     int64_t Imm;
458     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
459     if (!isImm())
460       return false;
461     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
462     if (VK == RISCVMCExpr::VK_RISCV_LO || VK == RISCVMCExpr::VK_RISCV_PCREL_LO)
463       return true;
464     // Given only Imm, ensuring that the actually specified constant is either
465     // a signed or unsigned 64-bit number is unfortunately impossible.
466     return IsConstantImm && VK == RISCVMCExpr::VK_RISCV_None &&
467            (isRV64() || (isInt<32>(Imm) || isUInt<32>(Imm)));
468   }
469 
470   bool isUImmLog2XLen() const {
471     int64_t Imm;
472     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
473     if (!isImm())
474       return false;
475     if (!evaluateConstantImm(getImm(), Imm, VK) ||
476         VK != RISCVMCExpr::VK_RISCV_None)
477       return false;
478     return (isRV64() && isUInt<6>(Imm)) || isUInt<5>(Imm);
479   }
480 
481   bool isUImmLog2XLenNonZero() const {
482     int64_t Imm;
483     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
484     if (!isImm())
485       return false;
486     if (!evaluateConstantImm(getImm(), Imm, VK) ||
487         VK != RISCVMCExpr::VK_RISCV_None)
488       return false;
489     if (Imm == 0)
490       return false;
491     return (isRV64() && isUInt<6>(Imm)) || isUInt<5>(Imm);
492   }
493 
494   bool isUImmLog2XLenHalf() const {
495     int64_t Imm;
496     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
497     if (!isImm())
498       return false;
499     if (!evaluateConstantImm(getImm(), Imm, VK) ||
500         VK != RISCVMCExpr::VK_RISCV_None)
501       return false;
502     return (isRV64() && isUInt<5>(Imm)) || isUInt<4>(Imm);
503   }
504 
505   bool isUImm5() const {
506     int64_t Imm;
507     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
508     if (!isImm())
509       return false;
510     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
511     return IsConstantImm && isUInt<5>(Imm) && VK == RISCVMCExpr::VK_RISCV_None;
512   }
513 
514   bool isUImm5NonZero() const {
515     int64_t Imm;
516     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
517     if (!isImm())
518       return false;
519     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
520     return IsConstantImm && isUInt<5>(Imm) && (Imm != 0) &&
521            VK == RISCVMCExpr::VK_RISCV_None;
522   }
523 
524   bool isSImm5() const {
525     if (!isImm())
526       return false;
527     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
528     int64_t Imm;
529     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
530     return IsConstantImm && isInt<5>(Imm) && VK == RISCVMCExpr::VK_RISCV_None;
531   }
532 
533   bool isSImm6() const {
534     if (!isImm())
535       return false;
536     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
537     int64_t Imm;
538     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
539     return IsConstantImm && isInt<6>(Imm) &&
540 	    VK == RISCVMCExpr::VK_RISCV_None;
541   }
542 
543   bool isSImm6NonZero() const {
544     if (!isImm())
545       return false;
546     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
547     int64_t Imm;
548     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
549     return IsConstantImm && isInt<6>(Imm) && (Imm != 0) &&
550            VK == RISCVMCExpr::VK_RISCV_None;
551   }
552 
553   bool isCLUIImm() const {
554     if (!isImm())
555       return false;
556     int64_t Imm;
557     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
558     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
559     return IsConstantImm && (Imm != 0) &&
560            (isUInt<5>(Imm) || (Imm >= 0xfffe0 && Imm <= 0xfffff)) &&
561            VK == RISCVMCExpr::VK_RISCV_None;
562   }
563 
564   bool isUImm7Lsb00() const {
565     if (!isImm())
566       return false;
567     int64_t Imm;
568     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
569     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
570     return IsConstantImm && isShiftedUInt<5, 2>(Imm) &&
571            VK == RISCVMCExpr::VK_RISCV_None;
572   }
573 
574   bool isUImm8Lsb00() const {
575     if (!isImm())
576       return false;
577     int64_t Imm;
578     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
579     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
580     return IsConstantImm && isShiftedUInt<6, 2>(Imm) &&
581            VK == RISCVMCExpr::VK_RISCV_None;
582   }
583 
584   bool isUImm8Lsb000() const {
585     if (!isImm())
586       return false;
587     int64_t Imm;
588     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
589     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
590     return IsConstantImm && isShiftedUInt<5, 3>(Imm) &&
591            VK == RISCVMCExpr::VK_RISCV_None;
592   }
593 
594   bool isSImm9Lsb0() const { return isBareSimmNLsb0<9>(); }
595 
596   bool isUImm9Lsb000() const {
597     if (!isImm())
598       return false;
599     int64_t Imm;
600     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
601     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
602     return IsConstantImm && isShiftedUInt<6, 3>(Imm) &&
603            VK == RISCVMCExpr::VK_RISCV_None;
604   }
605 
606   bool isUImm10Lsb00NonZero() const {
607     if (!isImm())
608       return false;
609     int64_t Imm;
610     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
611     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
612     return IsConstantImm && isShiftedUInt<8, 2>(Imm) && (Imm != 0) &&
613            VK == RISCVMCExpr::VK_RISCV_None;
614   }
615 
616   bool isSImm12() const {
617     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
618     int64_t Imm;
619     bool IsValid;
620     if (!isImm())
621       return false;
622     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
623     if (!IsConstantImm)
624       IsValid = RISCVAsmParser::classifySymbolRef(getImm(), VK);
625     else
626       IsValid = isInt<12>(Imm);
627     return IsValid && ((IsConstantImm && VK == RISCVMCExpr::VK_RISCV_None) ||
628                        VK == RISCVMCExpr::VK_RISCV_LO ||
629                        VK == RISCVMCExpr::VK_RISCV_PCREL_LO ||
630                        VK == RISCVMCExpr::VK_RISCV_TPREL_LO);
631   }
632 
633   bool isSImm12Lsb0() const { return isBareSimmNLsb0<12>(); }
634 
635   bool isSImm13Lsb0() const { return isBareSimmNLsb0<13>(); }
636 
637   bool isSImm10Lsb0000NonZero() const {
638     if (!isImm())
639       return false;
640     int64_t Imm;
641     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
642     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
643     return IsConstantImm && (Imm != 0) && isShiftedInt<6, 4>(Imm) &&
644            VK == RISCVMCExpr::VK_RISCV_None;
645   }
646 
647   bool isUImm20LUI() const {
648     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
649     int64_t Imm;
650     bool IsValid;
651     if (!isImm())
652       return false;
653     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
654     if (!IsConstantImm) {
655       IsValid = RISCVAsmParser::classifySymbolRef(getImm(), VK);
656       return IsValid && (VK == RISCVMCExpr::VK_RISCV_HI ||
657                          VK == RISCVMCExpr::VK_RISCV_TPREL_HI);
658     } else {
659       return isUInt<20>(Imm) && (VK == RISCVMCExpr::VK_RISCV_None ||
660                                  VK == RISCVMCExpr::VK_RISCV_HI ||
661                                  VK == RISCVMCExpr::VK_RISCV_TPREL_HI);
662     }
663   }
664 
665   bool isUImm20AUIPC() const {
666     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
667     int64_t Imm;
668     bool IsValid;
669     if (!isImm())
670       return false;
671     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
672     if (!IsConstantImm) {
673       IsValid = RISCVAsmParser::classifySymbolRef(getImm(), VK);
674       return IsValid && (VK == RISCVMCExpr::VK_RISCV_PCREL_HI ||
675                          VK == RISCVMCExpr::VK_RISCV_GOT_HI ||
676                          VK == RISCVMCExpr::VK_RISCV_TLS_GOT_HI ||
677                          VK == RISCVMCExpr::VK_RISCV_TLS_GD_HI);
678     } else {
679       return isUInt<20>(Imm) && (VK == RISCVMCExpr::VK_RISCV_None ||
680                                  VK == RISCVMCExpr::VK_RISCV_PCREL_HI ||
681                                  VK == RISCVMCExpr::VK_RISCV_GOT_HI ||
682                                  VK == RISCVMCExpr::VK_RISCV_TLS_GOT_HI ||
683                                  VK == RISCVMCExpr::VK_RISCV_TLS_GD_HI);
684     }
685   }
686 
687   bool isSImm21Lsb0JAL() const { return isBareSimmNLsb0<21>(); }
688 
689   bool isImmZero() const {
690     if (!isImm())
691       return false;
692     int64_t Imm;
693     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
694     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
695     return IsConstantImm && (Imm == 0) && VK == RISCVMCExpr::VK_RISCV_None;
696   }
697 
698   bool isSImm5Plus1() const {
699     if (!isImm())
700       return false;
701     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
702     int64_t Imm;
703     bool IsConstantImm = evaluateConstantImm(getImm(), Imm, VK);
704     return IsConstantImm && isInt<5>(Imm - 1) &&
705            VK == RISCVMCExpr::VK_RISCV_None;
706   }
707 
708   /// getStartLoc - Gets location of the first token of this operand
709   SMLoc getStartLoc() const override { return StartLoc; }
710   /// getEndLoc - Gets location of the last token of this operand
711   SMLoc getEndLoc() const override { return EndLoc; }
712   /// True if this operand is for an RV64 instruction
713   bool isRV64() const { return IsRV64; }
714 
715   unsigned getReg() const override {
716     assert(Kind == KindTy::Register && "Invalid type access!");
717     return Reg.RegNum.id();
718   }
719 
720   StringRef getSysReg() const {
721     assert(Kind == KindTy::SystemRegister && "Invalid type access!");
722     return StringRef(SysReg.Data, SysReg.Length);
723   }
724 
725   const MCExpr *getImm() const {
726     assert(Kind == KindTy::Immediate && "Invalid type access!");
727     return Imm.Val;
728   }
729 
730   StringRef getToken() const {
731     assert(Kind == KindTy::Token && "Invalid type access!");
732     return Tok;
733   }
734 
735   unsigned getVType() const {
736     assert(Kind == KindTy::VType && "Invalid type access!");
737     return VType.Val;
738   }
739 
740   void print(raw_ostream &OS) const override {
741     auto RegName = [](unsigned Reg) {
742       if (Reg)
743         return RISCVInstPrinter::getRegisterName(Reg);
744       else
745         return "noreg";
746     };
747 
748     switch (Kind) {
749     case KindTy::Immediate:
750       OS << *getImm();
751       break;
752     case KindTy::Register:
753       OS << "<register " << RegName(getReg()) << ">";
754       break;
755     case KindTy::Token:
756       OS << "'" << getToken() << "'";
757       break;
758     case KindTy::SystemRegister:
759       OS << "<sysreg: " << getSysReg() << '>';
760       break;
761     case KindTy::VType:
762       OS << "<vtype: ";
763       RISCVVType::printVType(getVType(), OS);
764       OS << '>';
765       break;
766     }
767   }
768 
769   static std::unique_ptr<RISCVOperand> createToken(StringRef Str, SMLoc S,
770                                                    bool IsRV64) {
771     auto Op = std::make_unique<RISCVOperand>(KindTy::Token);
772     Op->Tok = Str;
773     Op->StartLoc = S;
774     Op->EndLoc = S;
775     Op->IsRV64 = IsRV64;
776     return Op;
777   }
778 
779   static std::unique_ptr<RISCVOperand> createReg(unsigned RegNo, SMLoc S,
780                                                  SMLoc E, bool IsRV64) {
781     auto Op = std::make_unique<RISCVOperand>(KindTy::Register);
782     Op->Reg.RegNum = RegNo;
783     Op->StartLoc = S;
784     Op->EndLoc = E;
785     Op->IsRV64 = IsRV64;
786     return Op;
787   }
788 
789   static std::unique_ptr<RISCVOperand> createImm(const MCExpr *Val, SMLoc S,
790                                                  SMLoc E, bool IsRV64) {
791     auto Op = std::make_unique<RISCVOperand>(KindTy::Immediate);
792     Op->Imm.Val = Val;
793     Op->StartLoc = S;
794     Op->EndLoc = E;
795     Op->IsRV64 = IsRV64;
796     return Op;
797   }
798 
799   static std::unique_ptr<RISCVOperand>
800   createSysReg(StringRef Str, SMLoc S, unsigned Encoding, bool IsRV64) {
801     auto Op = std::make_unique<RISCVOperand>(KindTy::SystemRegister);
802     Op->SysReg.Data = Str.data();
803     Op->SysReg.Length = Str.size();
804     Op->SysReg.Encoding = Encoding;
805     Op->StartLoc = S;
806     Op->IsRV64 = IsRV64;
807     return Op;
808   }
809 
810   static std::unique_ptr<RISCVOperand> createVType(unsigned VTypeI, SMLoc S,
811                                                    bool IsRV64) {
812     auto Op = std::make_unique<RISCVOperand>(KindTy::VType);
813     Op->VType.Val = VTypeI;
814     Op->StartLoc = S;
815     Op->IsRV64 = IsRV64;
816     return Op;
817   }
818 
819   void addExpr(MCInst &Inst, const MCExpr *Expr) const {
820     assert(Expr && "Expr shouldn't be null!");
821     int64_t Imm = 0;
822     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
823     bool IsConstant = evaluateConstantImm(Expr, Imm, VK);
824 
825     if (IsConstant)
826       Inst.addOperand(MCOperand::createImm(Imm));
827     else
828       Inst.addOperand(MCOperand::createExpr(Expr));
829   }
830 
831   // Used by the TableGen Code
832   void addRegOperands(MCInst &Inst, unsigned N) const {
833     assert(N == 1 && "Invalid number of operands!");
834     Inst.addOperand(MCOperand::createReg(getReg()));
835   }
836 
837   void addImmOperands(MCInst &Inst, unsigned N) const {
838     assert(N == 1 && "Invalid number of operands!");
839     addExpr(Inst, getImm());
840   }
841 
842   void addSImm5Plus1Operands(MCInst &Inst, unsigned N) const {
843     assert(N == 1 && "Invalid number of operands!");
844     int64_t Imm = 0;
845     RISCVMCExpr::VariantKind VK = RISCVMCExpr::VK_RISCV_None;
846     bool IsConstant = evaluateConstantImm(getImm(), Imm, VK);
847     assert(IsConstant && "Expect constant value!");
848     (void)IsConstant;
849     Inst.addOperand(MCOperand::createImm(Imm - 1));
850   }
851 
852   void addFenceArgOperands(MCInst &Inst, unsigned N) const {
853     assert(N == 1 && "Invalid number of operands!");
854     // isFenceArg has validated the operand, meaning this cast is safe
855     auto SE = cast<MCSymbolRefExpr>(getImm());
856 
857     unsigned Imm = 0;
858     for (char c : SE->getSymbol().getName()) {
859       switch (c) {
860       default:
861         llvm_unreachable("FenceArg must contain only [iorw]");
862       case 'i': Imm |= RISCVFenceField::I; break;
863       case 'o': Imm |= RISCVFenceField::O; break;
864       case 'r': Imm |= RISCVFenceField::R; break;
865       case 'w': Imm |= RISCVFenceField::W; break;
866       }
867     }
868     Inst.addOperand(MCOperand::createImm(Imm));
869   }
870 
871   void addCSRSystemRegisterOperands(MCInst &Inst, unsigned N) const {
872     assert(N == 1 && "Invalid number of operands!");
873     Inst.addOperand(MCOperand::createImm(SysReg.Encoding));
874   }
875 
876   void addVTypeIOperands(MCInst &Inst, unsigned N) const {
877     assert(N == 1 && "Invalid number of operands!");
878     Inst.addOperand(MCOperand::createImm(getVType()));
879   }
880 
881   // Returns the rounding mode represented by this RISCVOperand. Should only
882   // be called after checking isFRMArg.
883   RISCVFPRndMode::RoundingMode getRoundingMode() const {
884     // isFRMArg has validated the operand, meaning this cast is safe.
885     auto SE = cast<MCSymbolRefExpr>(getImm());
886     RISCVFPRndMode::RoundingMode FRM =
887         RISCVFPRndMode::stringToRoundingMode(SE->getSymbol().getName());
888     assert(FRM != RISCVFPRndMode::Invalid && "Invalid rounding mode");
889     return FRM;
890   }
891 
892   void addFRMArgOperands(MCInst &Inst, unsigned N) const {
893     assert(N == 1 && "Invalid number of operands!");
894     Inst.addOperand(MCOperand::createImm(getRoundingMode()));
895   }
896 };
897 } // end anonymous namespace.
898 
899 #define GET_REGISTER_MATCHER
900 #define GET_SUBTARGET_FEATURE_NAME
901 #define GET_MATCHER_IMPLEMENTATION
902 #define GET_MNEMONIC_SPELL_CHECKER
903 #include "RISCVGenAsmMatcher.inc"
904 
905 static MCRegister convertFPR64ToFPR16(MCRegister Reg) {
906   assert(Reg >= RISCV::F0_D && Reg <= RISCV::F31_D && "Invalid register");
907   return Reg - RISCV::F0_D + RISCV::F0_H;
908 }
909 
910 static MCRegister convertFPR64ToFPR32(MCRegister Reg) {
911   assert(Reg >= RISCV::F0_D && Reg <= RISCV::F31_D && "Invalid register");
912   return Reg - RISCV::F0_D + RISCV::F0_F;
913 }
914 
915 unsigned RISCVAsmParser::validateTargetOperandClass(MCParsedAsmOperand &AsmOp,
916                                                     unsigned Kind) {
917   RISCVOperand &Op = static_cast<RISCVOperand &>(AsmOp);
918   if (!Op.isReg())
919     return Match_InvalidOperand;
920 
921   MCRegister Reg = Op.getReg();
922   bool IsRegFPR64 =
923       RISCVMCRegisterClasses[RISCV::FPR64RegClassID].contains(Reg);
924   bool IsRegFPR64C =
925       RISCVMCRegisterClasses[RISCV::FPR64CRegClassID].contains(Reg);
926 
927   // As the parser couldn't differentiate an FPR32 from an FPR64, coerce the
928   // register from FPR64 to FPR32 or FPR64C to FPR32C if necessary.
929   if ((IsRegFPR64 && Kind == MCK_FPR32) ||
930       (IsRegFPR64C && Kind == MCK_FPR32C)) {
931     Op.Reg.RegNum = convertFPR64ToFPR32(Reg);
932     return Match_Success;
933   }
934   // As the parser couldn't differentiate an FPR16 from an FPR64, coerce the
935   // register from FPR64 to FPR16 if necessary.
936   if (IsRegFPR64 && Kind == MCK_FPR16) {
937     Op.Reg.RegNum = convertFPR64ToFPR16(Reg);
938     return Match_Success;
939   }
940   return Match_InvalidOperand;
941 }
942 
943 bool RISCVAsmParser::generateImmOutOfRangeError(
944     OperandVector &Operands, uint64_t ErrorInfo, int64_t Lower, int64_t Upper,
945     Twine Msg = "immediate must be an integer in the range") {
946   SMLoc ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
947   return Error(ErrorLoc, Msg + " [" + Twine(Lower) + ", " + Twine(Upper) + "]");
948 }
949 
950 static std::string RISCVMnemonicSpellCheck(StringRef S,
951                                           const FeatureBitset &FBS,
952                                           unsigned VariantID = 0);
953 
954 bool RISCVAsmParser::MatchAndEmitInstruction(SMLoc IDLoc, unsigned &Opcode,
955                                              OperandVector &Operands,
956                                              MCStreamer &Out,
957                                              uint64_t &ErrorInfo,
958                                              bool MatchingInlineAsm) {
959   MCInst Inst;
960   FeatureBitset MissingFeatures;
961 
962   auto Result =
963     MatchInstructionImpl(Operands, Inst, ErrorInfo, MissingFeatures,
964                          MatchingInlineAsm);
965   switch (Result) {
966   default:
967     break;
968   case Match_Success:
969     if (validateInstruction(Inst, Operands))
970       return true;
971     return processInstruction(Inst, IDLoc, Operands, Out);
972   case Match_MissingFeature: {
973     assert(MissingFeatures.any() && "Unknown missing features!");
974     bool FirstFeature = true;
975     std::string Msg = "instruction requires the following:";
976     for (unsigned i = 0, e = MissingFeatures.size(); i != e; ++i) {
977       if (MissingFeatures[i]) {
978         Msg += FirstFeature ? " " : ", ";
979         Msg += getSubtargetFeatureName(i);
980         FirstFeature = false;
981       }
982     }
983     return Error(IDLoc, Msg);
984   }
985   case Match_MnemonicFail: {
986     FeatureBitset FBS = ComputeAvailableFeatures(getSTI().getFeatureBits());
987     std::string Suggestion = RISCVMnemonicSpellCheck(
988       ((RISCVOperand &)*Operands[0]).getToken(), FBS);
989     return Error(IDLoc, "unrecognized instruction mnemonic" + Suggestion);
990   }
991   case Match_InvalidOperand: {
992     SMLoc ErrorLoc = IDLoc;
993     if (ErrorInfo != ~0U) {
994       if (ErrorInfo >= Operands.size())
995         return Error(ErrorLoc, "too few operands for instruction");
996 
997       ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
998       if (ErrorLoc == SMLoc())
999         ErrorLoc = IDLoc;
1000     }
1001     return Error(ErrorLoc, "invalid operand for instruction");
1002   }
1003   }
1004 
1005   // Handle the case when the error message is of specific type
1006   // other than the generic Match_InvalidOperand, and the
1007   // corresponding operand is missing.
1008   if (Result > FIRST_TARGET_MATCH_RESULT_TY) {
1009     SMLoc ErrorLoc = IDLoc;
1010     if (ErrorInfo != ~0U && ErrorInfo >= Operands.size())
1011         return Error(ErrorLoc, "too few operands for instruction");
1012   }
1013 
1014   switch(Result) {
1015   default:
1016     break;
1017   case Match_InvalidImmXLenLI:
1018     if (isRV64()) {
1019       SMLoc ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
1020       return Error(ErrorLoc, "operand must be a constant 64-bit integer");
1021     }
1022     return generateImmOutOfRangeError(Operands, ErrorInfo,
1023                                       std::numeric_limits<int32_t>::min(),
1024                                       std::numeric_limits<uint32_t>::max());
1025   case Match_InvalidImmZero: {
1026     SMLoc ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
1027     return Error(ErrorLoc, "immediate must be zero");
1028   }
1029   case Match_InvalidUImmLog2XLen:
1030     if (isRV64())
1031       return generateImmOutOfRangeError(Operands, ErrorInfo, 0, (1 << 6) - 1);
1032     return generateImmOutOfRangeError(Operands, ErrorInfo, 0, (1 << 5) - 1);
1033   case Match_InvalidUImmLog2XLenNonZero:
1034     if (isRV64())
1035       return generateImmOutOfRangeError(Operands, ErrorInfo, 1, (1 << 6) - 1);
1036     return generateImmOutOfRangeError(Operands, ErrorInfo, 1, (1 << 5) - 1);
1037   case Match_InvalidUImmLog2XLenHalf:
1038     if (isRV64())
1039       return generateImmOutOfRangeError(Operands, ErrorInfo, 0, (1 << 5) - 1);
1040     return generateImmOutOfRangeError(Operands, ErrorInfo, 0, (1 << 4) - 1);
1041   case Match_InvalidUImm5:
1042     return generateImmOutOfRangeError(Operands, ErrorInfo, 0, (1 << 5) - 1);
1043   case Match_InvalidSImm5:
1044     return generateImmOutOfRangeError(Operands, ErrorInfo, -(1 << 4),
1045                                       (1 << 4) - 1);
1046   case Match_InvalidSImm6:
1047     return generateImmOutOfRangeError(Operands, ErrorInfo, -(1 << 5),
1048                                       (1 << 5) - 1);
1049   case Match_InvalidSImm6NonZero:
1050     return generateImmOutOfRangeError(
1051         Operands, ErrorInfo, -(1 << 5), (1 << 5) - 1,
1052         "immediate must be non-zero in the range");
1053   case Match_InvalidCLUIImm:
1054     return generateImmOutOfRangeError(
1055         Operands, ErrorInfo, 1, (1 << 5) - 1,
1056         "immediate must be in [0xfffe0, 0xfffff] or");
1057   case Match_InvalidUImm7Lsb00:
1058     return generateImmOutOfRangeError(
1059         Operands, ErrorInfo, 0, (1 << 7) - 4,
1060         "immediate must be a multiple of 4 bytes in the range");
1061   case Match_InvalidUImm8Lsb00:
1062     return generateImmOutOfRangeError(
1063         Operands, ErrorInfo, 0, (1 << 8) - 4,
1064         "immediate must be a multiple of 4 bytes in the range");
1065   case Match_InvalidUImm8Lsb000:
1066     return generateImmOutOfRangeError(
1067         Operands, ErrorInfo, 0, (1 << 8) - 8,
1068         "immediate must be a multiple of 8 bytes in the range");
1069   case Match_InvalidSImm9Lsb0:
1070     return generateImmOutOfRangeError(
1071         Operands, ErrorInfo, -(1 << 8), (1 << 8) - 2,
1072         "immediate must be a multiple of 2 bytes in the range");
1073   case Match_InvalidUImm9Lsb000:
1074     return generateImmOutOfRangeError(
1075         Operands, ErrorInfo, 0, (1 << 9) - 8,
1076         "immediate must be a multiple of 8 bytes in the range");
1077   case Match_InvalidUImm10Lsb00NonZero:
1078     return generateImmOutOfRangeError(
1079         Operands, ErrorInfo, 4, (1 << 10) - 4,
1080         "immediate must be a multiple of 4 bytes in the range");
1081   case Match_InvalidSImm10Lsb0000NonZero:
1082     return generateImmOutOfRangeError(
1083         Operands, ErrorInfo, -(1 << 9), (1 << 9) - 16,
1084         "immediate must be a multiple of 16 bytes and non-zero in the range");
1085   case Match_InvalidSImm12:
1086     return generateImmOutOfRangeError(
1087         Operands, ErrorInfo, -(1 << 11), (1 << 11) - 1,
1088         "operand must be a symbol with %lo/%pcrel_lo/%tprel_lo modifier or an "
1089         "integer in the range");
1090   case Match_InvalidSImm12Lsb0:
1091     return generateImmOutOfRangeError(
1092         Operands, ErrorInfo, -(1 << 11), (1 << 11) - 2,
1093         "immediate must be a multiple of 2 bytes in the range");
1094   case Match_InvalidSImm13Lsb0:
1095     return generateImmOutOfRangeError(
1096         Operands, ErrorInfo, -(1 << 12), (1 << 12) - 2,
1097         "immediate must be a multiple of 2 bytes in the range");
1098   case Match_InvalidUImm20LUI:
1099     return generateImmOutOfRangeError(Operands, ErrorInfo, 0, (1 << 20) - 1,
1100                                       "operand must be a symbol with "
1101                                       "%hi/%tprel_hi modifier or an integer in "
1102                                       "the range");
1103   case Match_InvalidUImm20AUIPC:
1104     return generateImmOutOfRangeError(
1105         Operands, ErrorInfo, 0, (1 << 20) - 1,
1106         "operand must be a symbol with a "
1107         "%pcrel_hi/%got_pcrel_hi/%tls_ie_pcrel_hi/%tls_gd_pcrel_hi modifier or "
1108         "an integer in the range");
1109   case Match_InvalidSImm21Lsb0JAL:
1110     return generateImmOutOfRangeError(
1111         Operands, ErrorInfo, -(1 << 20), (1 << 20) - 2,
1112         "immediate must be a multiple of 2 bytes in the range");
1113   case Match_InvalidCSRSystemRegister: {
1114     return generateImmOutOfRangeError(Operands, ErrorInfo, 0, (1 << 12) - 1,
1115                                       "operand must be a valid system register "
1116                                       "name or an integer in the range");
1117   }
1118   case Match_InvalidFenceArg: {
1119     SMLoc ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
1120     return Error(
1121         ErrorLoc,
1122         "operand must be formed of letters selected in-order from 'iorw'");
1123   }
1124   case Match_InvalidFRMArg: {
1125     SMLoc ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
1126     return Error(
1127         ErrorLoc,
1128         "operand must be a valid floating point rounding mode mnemonic");
1129   }
1130   case Match_InvalidBareSymbol: {
1131     SMLoc ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
1132     return Error(ErrorLoc, "operand must be a bare symbol name");
1133   }
1134   case Match_InvalidPseudoJumpSymbol: {
1135     SMLoc ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
1136     return Error(ErrorLoc, "operand must be a valid jump target");
1137   }
1138   case Match_InvalidCallSymbol: {
1139     SMLoc ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
1140     return Error(ErrorLoc, "operand must be a bare symbol name");
1141   }
1142   case Match_InvalidTPRelAddSymbol: {
1143     SMLoc ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
1144     return Error(ErrorLoc, "operand must be a symbol with %tprel_add modifier");
1145   }
1146   case Match_InvalidVTypeI: {
1147     SMLoc ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
1148     return Error(
1149         ErrorLoc,
1150         "operand must be "
1151         "e[8|16|32|64|128|256|512|1024],m[1|2|4|8|f2|f4|f8],[ta|tu],[ma|mu]");
1152   }
1153   case Match_InvalidVMaskRegister: {
1154     SMLoc ErrorLoc = ((RISCVOperand &)*Operands[ErrorInfo]).getStartLoc();
1155     return Error(ErrorLoc, "operand must be v0.t");
1156   }
1157   case Match_InvalidSImm5Plus1: {
1158     return generateImmOutOfRangeError(Operands, ErrorInfo, -(1 << 4) + 1,
1159                                       (1 << 4),
1160                                       "immediate must be in the range");
1161   }
1162   }
1163 
1164   llvm_unreachable("Unknown match type detected!");
1165 }
1166 
1167 // Attempts to match Name as a register (either using the default name or
1168 // alternative ABI names), setting RegNo to the matching register. Upon
1169 // failure, returns true and sets RegNo to 0. If IsRV32E then registers
1170 // x16-x31 will be rejected.
1171 static bool matchRegisterNameHelper(bool IsRV32E, MCRegister &RegNo,
1172                                     StringRef Name) {
1173   RegNo = MatchRegisterName(Name);
1174   // The 16-/32- and 64-bit FPRs have the same asm name. Check that the initial
1175   // match always matches the 64-bit variant, and not the 16/32-bit one.
1176   assert(!(RegNo >= RISCV::F0_H && RegNo <= RISCV::F31_H));
1177   assert(!(RegNo >= RISCV::F0_F && RegNo <= RISCV::F31_F));
1178   // The default FPR register class is based on the tablegen enum ordering.
1179   static_assert(RISCV::F0_D < RISCV::F0_H, "FPR matching must be updated");
1180   static_assert(RISCV::F0_D < RISCV::F0_F, "FPR matching must be updated");
1181   if (RegNo == RISCV::NoRegister)
1182     RegNo = MatchRegisterAltName(Name);
1183   if (IsRV32E && RegNo >= RISCV::X16 && RegNo <= RISCV::X31)
1184     RegNo = RISCV::NoRegister;
1185   return RegNo == RISCV::NoRegister;
1186 }
1187 
1188 bool RISCVAsmParser::ParseRegister(unsigned &RegNo, SMLoc &StartLoc,
1189                                    SMLoc &EndLoc) {
1190   if (tryParseRegister(RegNo, StartLoc, EndLoc) != MatchOperand_Success)
1191     return Error(StartLoc, "invalid register name");
1192   return false;
1193 }
1194 
1195 OperandMatchResultTy RISCVAsmParser::tryParseRegister(unsigned &RegNo,
1196                                                       SMLoc &StartLoc,
1197                                                       SMLoc &EndLoc) {
1198   const AsmToken &Tok = getParser().getTok();
1199   StartLoc = Tok.getLoc();
1200   EndLoc = Tok.getEndLoc();
1201   RegNo = 0;
1202   StringRef Name = getLexer().getTok().getIdentifier();
1203 
1204   if (matchRegisterNameHelper(isRV32E(), (MCRegister &)RegNo, Name))
1205     return MatchOperand_NoMatch;
1206 
1207   getParser().Lex(); // Eat identifier token.
1208   return MatchOperand_Success;
1209 }
1210 
1211 OperandMatchResultTy RISCVAsmParser::parseRegister(OperandVector &Operands,
1212                                                    bool AllowParens) {
1213   SMLoc FirstS = getLoc();
1214   bool HadParens = false;
1215   AsmToken LParen;
1216 
1217   // If this is an LParen and a parenthesised register name is allowed, parse it
1218   // atomically.
1219   if (AllowParens && getLexer().is(AsmToken::LParen)) {
1220     AsmToken Buf[2];
1221     size_t ReadCount = getLexer().peekTokens(Buf);
1222     if (ReadCount == 2 && Buf[1].getKind() == AsmToken::RParen) {
1223       HadParens = true;
1224       LParen = getParser().getTok();
1225       getParser().Lex(); // Eat '('
1226     }
1227   }
1228 
1229   switch (getLexer().getKind()) {
1230   default:
1231     if (HadParens)
1232       getLexer().UnLex(LParen);
1233     return MatchOperand_NoMatch;
1234   case AsmToken::Identifier:
1235     StringRef Name = getLexer().getTok().getIdentifier();
1236     MCRegister RegNo;
1237     matchRegisterNameHelper(isRV32E(), RegNo, Name);
1238 
1239     if (RegNo == RISCV::NoRegister) {
1240       if (HadParens)
1241         getLexer().UnLex(LParen);
1242       return MatchOperand_NoMatch;
1243     }
1244     if (HadParens)
1245       Operands.push_back(RISCVOperand::createToken("(", FirstS, isRV64()));
1246     SMLoc S = getLoc();
1247     SMLoc E = SMLoc::getFromPointer(S.getPointer() - 1);
1248     getLexer().Lex();
1249     Operands.push_back(RISCVOperand::createReg(RegNo, S, E, isRV64()));
1250   }
1251 
1252   if (HadParens) {
1253     getParser().Lex(); // Eat ')'
1254     Operands.push_back(RISCVOperand::createToken(")", getLoc(), isRV64()));
1255   }
1256 
1257   return MatchOperand_Success;
1258 }
1259 
1260 OperandMatchResultTy
1261 RISCVAsmParser::parseCSRSystemRegister(OperandVector &Operands) {
1262   SMLoc S = getLoc();
1263   const MCExpr *Res;
1264 
1265   switch (getLexer().getKind()) {
1266   default:
1267     return MatchOperand_NoMatch;
1268   case AsmToken::LParen:
1269   case AsmToken::Minus:
1270   case AsmToken::Plus:
1271   case AsmToken::Exclaim:
1272   case AsmToken::Tilde:
1273   case AsmToken::Integer:
1274   case AsmToken::String: {
1275     if (getParser().parseExpression(Res))
1276       return MatchOperand_ParseFail;
1277 
1278     auto *CE = dyn_cast<MCConstantExpr>(Res);
1279     if (CE) {
1280       int64_t Imm = CE->getValue();
1281       if (isUInt<12>(Imm)) {
1282         auto SysReg = RISCVSysReg::lookupSysRegByEncoding(Imm);
1283         // Accept an immediate representing a named or un-named Sys Reg
1284         // if the range is valid, regardless of the required features.
1285         Operands.push_back(RISCVOperand::createSysReg(
1286             SysReg ? SysReg->Name : "", S, Imm, isRV64()));
1287         return MatchOperand_Success;
1288       }
1289     }
1290 
1291     Twine Msg = "immediate must be an integer in the range";
1292     Error(S, Msg + " [" + Twine(0) + ", " + Twine((1 << 12) - 1) + "]");
1293     return MatchOperand_ParseFail;
1294   }
1295   case AsmToken::Identifier: {
1296     StringRef Identifier;
1297     if (getParser().parseIdentifier(Identifier))
1298       return MatchOperand_ParseFail;
1299 
1300     auto SysReg = RISCVSysReg::lookupSysRegByName(Identifier);
1301     if (!SysReg)
1302       SysReg = RISCVSysReg::lookupSysRegByAltName(Identifier);
1303     // Accept a named Sys Reg if the required features are present.
1304     if (SysReg) {
1305       if (!SysReg->haveRequiredFeatures(getSTI().getFeatureBits())) {
1306         Error(S, "system register use requires an option to be enabled");
1307         return MatchOperand_ParseFail;
1308       }
1309       Operands.push_back(RISCVOperand::createSysReg(
1310           Identifier, S, SysReg->Encoding, isRV64()));
1311       return MatchOperand_Success;
1312     }
1313 
1314     Twine Msg = "operand must be a valid system register name "
1315                 "or an integer in the range";
1316     Error(S, Msg + " [" + Twine(0) + ", " + Twine((1 << 12) - 1) + "]");
1317     return MatchOperand_ParseFail;
1318   }
1319   case AsmToken::Percent: {
1320     // Discard operand with modifier.
1321     Twine Msg = "immediate must be an integer in the range";
1322     Error(S, Msg + " [" + Twine(0) + ", " + Twine((1 << 12) - 1) + "]");
1323     return MatchOperand_ParseFail;
1324   }
1325   }
1326 
1327   return MatchOperand_NoMatch;
1328 }
1329 
1330 OperandMatchResultTy RISCVAsmParser::parseImmediate(OperandVector &Operands) {
1331   SMLoc S = getLoc();
1332   SMLoc E = SMLoc::getFromPointer(S.getPointer() - 1);
1333   const MCExpr *Res;
1334 
1335   switch (getLexer().getKind()) {
1336   default:
1337     return MatchOperand_NoMatch;
1338   case AsmToken::LParen:
1339   case AsmToken::Dot:
1340   case AsmToken::Minus:
1341   case AsmToken::Plus:
1342   case AsmToken::Exclaim:
1343   case AsmToken::Tilde:
1344   case AsmToken::Integer:
1345   case AsmToken::String:
1346   case AsmToken::Identifier:
1347     if (getParser().parseExpression(Res))
1348       return MatchOperand_ParseFail;
1349     break;
1350   case AsmToken::Percent:
1351     return parseOperandWithModifier(Operands);
1352   }
1353 
1354   Operands.push_back(RISCVOperand::createImm(Res, S, E, isRV64()));
1355   return MatchOperand_Success;
1356 }
1357 
1358 OperandMatchResultTy
1359 RISCVAsmParser::parseOperandWithModifier(OperandVector &Operands) {
1360   SMLoc S = getLoc();
1361   SMLoc E = SMLoc::getFromPointer(S.getPointer() - 1);
1362 
1363   if (getLexer().getKind() != AsmToken::Percent) {
1364     Error(getLoc(), "expected '%' for operand modifier");
1365     return MatchOperand_ParseFail;
1366   }
1367 
1368   getParser().Lex(); // Eat '%'
1369 
1370   if (getLexer().getKind() != AsmToken::Identifier) {
1371     Error(getLoc(), "expected valid identifier for operand modifier");
1372     return MatchOperand_ParseFail;
1373   }
1374   StringRef Identifier = getParser().getTok().getIdentifier();
1375   RISCVMCExpr::VariantKind VK = RISCVMCExpr::getVariantKindForName(Identifier);
1376   if (VK == RISCVMCExpr::VK_RISCV_Invalid) {
1377     Error(getLoc(), "unrecognized operand modifier");
1378     return MatchOperand_ParseFail;
1379   }
1380 
1381   getParser().Lex(); // Eat the identifier
1382   if (getLexer().getKind() != AsmToken::LParen) {
1383     Error(getLoc(), "expected '('");
1384     return MatchOperand_ParseFail;
1385   }
1386   getParser().Lex(); // Eat '('
1387 
1388   const MCExpr *SubExpr;
1389   if (getParser().parseParenExpression(SubExpr, E)) {
1390     return MatchOperand_ParseFail;
1391   }
1392 
1393   const MCExpr *ModExpr = RISCVMCExpr::create(SubExpr, VK, getContext());
1394   Operands.push_back(RISCVOperand::createImm(ModExpr, S, E, isRV64()));
1395   return MatchOperand_Success;
1396 }
1397 
1398 OperandMatchResultTy RISCVAsmParser::parseBareSymbol(OperandVector &Operands) {
1399   SMLoc S = getLoc();
1400   SMLoc E = SMLoc::getFromPointer(S.getPointer() - 1);
1401   const MCExpr *Res;
1402 
1403   if (getLexer().getKind() != AsmToken::Identifier)
1404     return MatchOperand_NoMatch;
1405 
1406   StringRef Identifier;
1407   AsmToken Tok = getLexer().getTok();
1408 
1409   if (getParser().parseIdentifier(Identifier))
1410     return MatchOperand_ParseFail;
1411 
1412   if (Identifier.consume_back("@plt")) {
1413     Error(getLoc(), "'@plt' operand not valid for instruction");
1414     return MatchOperand_ParseFail;
1415   }
1416 
1417   MCSymbol *Sym = getContext().getOrCreateSymbol(Identifier);
1418 
1419   if (Sym->isVariable()) {
1420     const MCExpr *V = Sym->getVariableValue(/*SetUsed=*/false);
1421     if (!isa<MCSymbolRefExpr>(V)) {
1422       getLexer().UnLex(Tok); // Put back if it's not a bare symbol.
1423       return MatchOperand_NoMatch;
1424     }
1425     Res = V;
1426   } else
1427     Res = MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_None, getContext());
1428 
1429   MCBinaryExpr::Opcode Opcode;
1430   switch (getLexer().getKind()) {
1431   default:
1432     Operands.push_back(RISCVOperand::createImm(Res, S, E, isRV64()));
1433     return MatchOperand_Success;
1434   case AsmToken::Plus:
1435     Opcode = MCBinaryExpr::Add;
1436     break;
1437   case AsmToken::Minus:
1438     Opcode = MCBinaryExpr::Sub;
1439     break;
1440   }
1441 
1442   const MCExpr *Expr;
1443   if (getParser().parseExpression(Expr))
1444     return MatchOperand_ParseFail;
1445   Res = MCBinaryExpr::create(Opcode, Res, Expr, getContext());
1446   Operands.push_back(RISCVOperand::createImm(Res, S, E, isRV64()));
1447   return MatchOperand_Success;
1448 }
1449 
1450 OperandMatchResultTy RISCVAsmParser::parseCallSymbol(OperandVector &Operands) {
1451   SMLoc S = getLoc();
1452   SMLoc E = SMLoc::getFromPointer(S.getPointer() - 1);
1453   const MCExpr *Res;
1454 
1455   if (getLexer().getKind() != AsmToken::Identifier)
1456     return MatchOperand_NoMatch;
1457 
1458   // Avoid parsing the register in `call rd, foo` as a call symbol.
1459   if (getLexer().peekTok().getKind() != AsmToken::EndOfStatement)
1460     return MatchOperand_NoMatch;
1461 
1462   StringRef Identifier;
1463   if (getParser().parseIdentifier(Identifier))
1464     return MatchOperand_ParseFail;
1465 
1466   RISCVMCExpr::VariantKind Kind = RISCVMCExpr::VK_RISCV_CALL;
1467   if (Identifier.consume_back("@plt"))
1468     Kind = RISCVMCExpr::VK_RISCV_CALL_PLT;
1469 
1470   MCSymbol *Sym = getContext().getOrCreateSymbol(Identifier);
1471   Res = MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_None, getContext());
1472   Res = RISCVMCExpr::create(Res, Kind, getContext());
1473   Operands.push_back(RISCVOperand::createImm(Res, S, E, isRV64()));
1474   return MatchOperand_Success;
1475 }
1476 
1477 OperandMatchResultTy
1478 RISCVAsmParser::parsePseudoJumpSymbol(OperandVector &Operands) {
1479   SMLoc S = getLoc();
1480   SMLoc E = SMLoc::getFromPointer(S.getPointer() - 1);
1481   const MCExpr *Res;
1482 
1483   if (getParser().parseExpression(Res))
1484     return MatchOperand_ParseFail;
1485 
1486   if (Res->getKind() != MCExpr::ExprKind::SymbolRef ||
1487       cast<MCSymbolRefExpr>(Res)->getKind() ==
1488           MCSymbolRefExpr::VariantKind::VK_PLT) {
1489     Error(S, "operand must be a valid jump target");
1490     return MatchOperand_ParseFail;
1491   }
1492 
1493   Res = RISCVMCExpr::create(Res, RISCVMCExpr::VK_RISCV_CALL, getContext());
1494   Operands.push_back(RISCVOperand::createImm(Res, S, E, isRV64()));
1495   return MatchOperand_Success;
1496 }
1497 
1498 OperandMatchResultTy RISCVAsmParser::parseJALOffset(OperandVector &Operands) {
1499   // Parsing jal operands is fiddly due to the `jal foo` and `jal ra, foo`
1500   // both being acceptable forms. When parsing `jal ra, foo` this function
1501   // will be called for the `ra` register operand in an attempt to match the
1502   // single-operand alias. parseJALOffset must fail for this case. It would
1503   // seem logical to try parse the operand using parseImmediate and return
1504   // NoMatch if the next token is a comma (meaning we must be parsing a jal in
1505   // the second form rather than the first). We can't do this as there's no
1506   // way of rewinding the lexer state. Instead, return NoMatch if this operand
1507   // is an identifier and is followed by a comma.
1508   if (getLexer().is(AsmToken::Identifier) &&
1509       getLexer().peekTok().is(AsmToken::Comma))
1510     return MatchOperand_NoMatch;
1511 
1512   return parseImmediate(Operands);
1513 }
1514 
1515 OperandMatchResultTy RISCVAsmParser::parseVTypeI(OperandVector &Operands) {
1516   SMLoc S = getLoc();
1517   if (getLexer().getKind() != AsmToken::Identifier)
1518     return MatchOperand_NoMatch;
1519 
1520   // Parse "e8,m1,t[a|u],m[a|u]"
1521   StringRef Name = getLexer().getTok().getIdentifier();
1522   if (!Name.consume_front("e"))
1523     return MatchOperand_NoMatch;
1524   unsigned Sew;
1525   if (Name.getAsInteger(10, Sew))
1526     return MatchOperand_NoMatch;
1527   if (!RISCVVType::isValidSEW(Sew))
1528     return MatchOperand_NoMatch;
1529   getLexer().Lex();
1530 
1531   if (!getLexer().is(AsmToken::Comma))
1532     return MatchOperand_NoMatch;
1533   getLexer().Lex();
1534 
1535   Name = getLexer().getTok().getIdentifier();
1536   if (!Name.consume_front("m"))
1537     return MatchOperand_NoMatch;
1538   // "m" or "mf"
1539   bool Fractional = Name.consume_front("f");
1540   unsigned Lmul;
1541   if (Name.getAsInteger(10, Lmul))
1542     return MatchOperand_NoMatch;
1543   if (!RISCVVType::isValidLMUL(Lmul, Fractional))
1544     return MatchOperand_NoMatch;
1545   getLexer().Lex();
1546 
1547   if (!getLexer().is(AsmToken::Comma))
1548     return MatchOperand_NoMatch;
1549   getLexer().Lex();
1550 
1551   Name = getLexer().getTok().getIdentifier();
1552   // ta or tu
1553   bool TailAgnostic;
1554   if (Name == "ta")
1555     TailAgnostic = true;
1556   else if (Name == "tu")
1557     TailAgnostic = false;
1558   else
1559     return MatchOperand_NoMatch;
1560   getLexer().Lex();
1561 
1562   if (!getLexer().is(AsmToken::Comma))
1563     return MatchOperand_NoMatch;
1564   getLexer().Lex();
1565 
1566   Name = getLexer().getTok().getIdentifier();
1567   // ma or mu
1568   bool MaskAgnostic;
1569   if (Name == "ma")
1570     MaskAgnostic = true;
1571   else if (Name == "mu")
1572     MaskAgnostic = false;
1573   else
1574     return MatchOperand_NoMatch;
1575   getLexer().Lex();
1576 
1577   if (getLexer().getKind() != AsmToken::EndOfStatement)
1578     return MatchOperand_NoMatch;
1579 
1580   unsigned SewLog2 = Log2_32(Sew / 8);
1581   unsigned LmulLog2 = Log2_32(Lmul);
1582   RISCVVSEW VSEW = static_cast<RISCVVSEW>(SewLog2);
1583   RISCVVLMUL VLMUL =
1584       static_cast<RISCVVLMUL>(Fractional ? 8 - LmulLog2 : LmulLog2);
1585 
1586   unsigned VTypeI =
1587       RISCVVType::encodeVTYPE(VLMUL, VSEW, TailAgnostic, MaskAgnostic);
1588   Operands.push_back(RISCVOperand::createVType(VTypeI, S, isRV64()));
1589 
1590   return MatchOperand_Success;
1591 }
1592 
1593 OperandMatchResultTy RISCVAsmParser::parseMaskReg(OperandVector &Operands) {
1594   switch (getLexer().getKind()) {
1595   default:
1596     return MatchOperand_NoMatch;
1597   case AsmToken::Identifier:
1598     StringRef Name = getLexer().getTok().getIdentifier();
1599     if (!Name.consume_back(".t")) {
1600       Error(getLoc(), "expected '.t' suffix");
1601       return MatchOperand_ParseFail;
1602     }
1603     MCRegister RegNo;
1604     matchRegisterNameHelper(isRV32E(), RegNo, Name);
1605 
1606     if (RegNo == RISCV::NoRegister)
1607       return MatchOperand_NoMatch;
1608     if (RegNo != RISCV::V0)
1609       return MatchOperand_NoMatch;
1610     SMLoc S = getLoc();
1611     SMLoc E = SMLoc::getFromPointer(S.getPointer() - 1);
1612     getLexer().Lex();
1613     Operands.push_back(RISCVOperand::createReg(RegNo, S, E, isRV64()));
1614   }
1615 
1616   return MatchOperand_Success;
1617 }
1618 
1619 OperandMatchResultTy
1620 RISCVAsmParser::parseMemOpBaseReg(OperandVector &Operands) {
1621   if (getLexer().isNot(AsmToken::LParen)) {
1622     Error(getLoc(), "expected '('");
1623     return MatchOperand_ParseFail;
1624   }
1625 
1626   getParser().Lex(); // Eat '('
1627   Operands.push_back(RISCVOperand::createToken("(", getLoc(), isRV64()));
1628 
1629   if (parseRegister(Operands) != MatchOperand_Success) {
1630     Error(getLoc(), "expected register");
1631     return MatchOperand_ParseFail;
1632   }
1633 
1634   if (getLexer().isNot(AsmToken::RParen)) {
1635     Error(getLoc(), "expected ')'");
1636     return MatchOperand_ParseFail;
1637   }
1638 
1639   getParser().Lex(); // Eat ')'
1640   Operands.push_back(RISCVOperand::createToken(")", getLoc(), isRV64()));
1641 
1642   return MatchOperand_Success;
1643 }
1644 
1645 OperandMatchResultTy RISCVAsmParser::parseAtomicMemOp(OperandVector &Operands) {
1646   // Atomic operations such as lr.w, sc.w, and amo*.w accept a "memory operand"
1647   // as one of their register operands, such as `(a0)`. This just denotes that
1648   // the register (in this case `a0`) contains a memory address.
1649   //
1650   // Normally, we would be able to parse these by putting the parens into the
1651   // instruction string. However, GNU as also accepts a zero-offset memory
1652   // operand (such as `0(a0)`), and ignores the 0. Normally this would be parsed
1653   // with parseImmediate followed by parseMemOpBaseReg, but these instructions
1654   // do not accept an immediate operand, and we do not want to add a "dummy"
1655   // operand that is silently dropped.
1656   //
1657   // Instead, we use this custom parser. This will: allow (and discard) an
1658   // offset if it is zero; require (and discard) parentheses; and add only the
1659   // parsed register operand to `Operands`.
1660   //
1661   // These operands are printed with RISCVInstPrinter::printAtomicMemOp, which
1662   // will only print the register surrounded by parentheses (which GNU as also
1663   // uses as its canonical representation for these operands).
1664   std::unique_ptr<RISCVOperand> OptionalImmOp;
1665 
1666   if (getLexer().isNot(AsmToken::LParen)) {
1667     // Parse an Integer token. We do not accept arbritrary constant expressions
1668     // in the offset field (because they may include parens, which complicates
1669     // parsing a lot).
1670     int64_t ImmVal;
1671     SMLoc ImmStart = getLoc();
1672     if (getParser().parseIntToken(ImmVal,
1673                                   "expected '(' or optional integer offset"))
1674       return MatchOperand_ParseFail;
1675 
1676     // Create a RISCVOperand for checking later (so the error messages are
1677     // nicer), but we don't add it to Operands.
1678     SMLoc ImmEnd = getLoc();
1679     OptionalImmOp =
1680         RISCVOperand::createImm(MCConstantExpr::create(ImmVal, getContext()),
1681                                 ImmStart, ImmEnd, isRV64());
1682   }
1683 
1684   if (getLexer().isNot(AsmToken::LParen)) {
1685     Error(getLoc(), OptionalImmOp ? "expected '(' after optional integer offset"
1686                                   : "expected '(' or optional integer offset");
1687     return MatchOperand_ParseFail;
1688   }
1689   getParser().Lex(); // Eat '('
1690 
1691   if (parseRegister(Operands) != MatchOperand_Success) {
1692     Error(getLoc(), "expected register");
1693     return MatchOperand_ParseFail;
1694   }
1695 
1696   if (getLexer().isNot(AsmToken::RParen)) {
1697     Error(getLoc(), "expected ')'");
1698     return MatchOperand_ParseFail;
1699   }
1700   getParser().Lex(); // Eat ')'
1701 
1702   // Deferred Handling of non-zero offsets. This makes the error messages nicer.
1703   if (OptionalImmOp && !OptionalImmOp->isImmZero()) {
1704     Error(OptionalImmOp->getStartLoc(), "optional integer offset must be 0",
1705           SMRange(OptionalImmOp->getStartLoc(), OptionalImmOp->getEndLoc()));
1706     return MatchOperand_ParseFail;
1707   }
1708 
1709   return MatchOperand_Success;
1710 }
1711 
1712 /// Looks at a token type and creates the relevant operand from this
1713 /// information, adding to Operands. If operand was parsed, returns false, else
1714 /// true.
1715 bool RISCVAsmParser::parseOperand(OperandVector &Operands, StringRef Mnemonic) {
1716   // Check if the current operand has a custom associated parser, if so, try to
1717   // custom parse the operand, or fallback to the general approach.
1718   OperandMatchResultTy Result =
1719       MatchOperandParserImpl(Operands, Mnemonic, /*ParseForAllFeatures=*/true);
1720   if (Result == MatchOperand_Success)
1721     return false;
1722   if (Result == MatchOperand_ParseFail)
1723     return true;
1724 
1725   // Attempt to parse token as a register.
1726   if (parseRegister(Operands, true) == MatchOperand_Success)
1727     return false;
1728 
1729   // Attempt to parse token as an immediate
1730   if (parseImmediate(Operands) == MatchOperand_Success) {
1731     // Parse memory base register if present
1732     if (getLexer().is(AsmToken::LParen))
1733       return parseMemOpBaseReg(Operands) != MatchOperand_Success;
1734     return false;
1735   }
1736 
1737   // Finally we have exhausted all options and must declare defeat.
1738   Error(getLoc(), "unknown operand");
1739   return true;
1740 }
1741 
1742 bool RISCVAsmParser::ParseInstruction(ParseInstructionInfo &Info,
1743                                       StringRef Name, SMLoc NameLoc,
1744                                       OperandVector &Operands) {
1745   // Ensure that if the instruction occurs when relaxation is enabled,
1746   // relocations are forced for the file. Ideally this would be done when there
1747   // is enough information to reliably determine if the instruction itself may
1748   // cause relaxations. Unfortunately instruction processing stage occurs in the
1749   // same pass as relocation emission, so it's too late to set a 'sticky bit'
1750   // for the entire file.
1751   if (getSTI().getFeatureBits()[RISCV::FeatureRelax]) {
1752     auto *Assembler = getTargetStreamer().getStreamer().getAssemblerPtr();
1753     if (Assembler != nullptr) {
1754       RISCVAsmBackend &MAB =
1755           static_cast<RISCVAsmBackend &>(Assembler->getBackend());
1756       MAB.setForceRelocs();
1757     }
1758   }
1759 
1760   // First operand is token for instruction
1761   Operands.push_back(RISCVOperand::createToken(Name, NameLoc, isRV64()));
1762 
1763   // If there are no more operands, then finish
1764   if (getLexer().is(AsmToken::EndOfStatement))
1765     return false;
1766 
1767   // Parse first operand
1768   if (parseOperand(Operands, Name))
1769     return true;
1770 
1771   // Parse until end of statement, consuming commas between operands
1772   unsigned OperandIdx = 1;
1773   while (getLexer().is(AsmToken::Comma)) {
1774     // Consume comma token
1775     getLexer().Lex();
1776 
1777     // Parse next operand
1778     if (parseOperand(Operands, Name))
1779       return true;
1780 
1781     ++OperandIdx;
1782   }
1783 
1784   if (getLexer().isNot(AsmToken::EndOfStatement)) {
1785     SMLoc Loc = getLexer().getLoc();
1786     getParser().eatToEndOfStatement();
1787     return Error(Loc, "unexpected token");
1788   }
1789 
1790   getParser().Lex(); // Consume the EndOfStatement.
1791   return false;
1792 }
1793 
1794 bool RISCVAsmParser::classifySymbolRef(const MCExpr *Expr,
1795                                        RISCVMCExpr::VariantKind &Kind) {
1796   Kind = RISCVMCExpr::VK_RISCV_None;
1797 
1798   if (const RISCVMCExpr *RE = dyn_cast<RISCVMCExpr>(Expr)) {
1799     Kind = RE->getKind();
1800     Expr = RE->getSubExpr();
1801   }
1802 
1803   MCValue Res;
1804   MCFixup Fixup;
1805   if (Expr->evaluateAsRelocatable(Res, nullptr, &Fixup))
1806     return Res.getRefKind() == RISCVMCExpr::VK_RISCV_None;
1807   return false;
1808 }
1809 
1810 bool RISCVAsmParser::ParseDirective(AsmToken DirectiveID) {
1811   // This returns false if this function recognizes the directive
1812   // regardless of whether it is successfully handles or reports an
1813   // error. Otherwise it returns true to give the generic parser a
1814   // chance at recognizing it.
1815   StringRef IDVal = DirectiveID.getString();
1816 
1817   if (IDVal == ".option")
1818     return parseDirectiveOption();
1819   else if (IDVal == ".attribute")
1820     return parseDirectiveAttribute();
1821 
1822   return true;
1823 }
1824 
1825 bool RISCVAsmParser::parseDirectiveOption() {
1826   MCAsmParser &Parser = getParser();
1827   // Get the option token.
1828   AsmToken Tok = Parser.getTok();
1829   // At the moment only identifiers are supported.
1830   if (Tok.isNot(AsmToken::Identifier))
1831     return Error(Parser.getTok().getLoc(),
1832                  "unexpected token, expected identifier");
1833 
1834   StringRef Option = Tok.getIdentifier();
1835 
1836   if (Option == "push") {
1837     getTargetStreamer().emitDirectiveOptionPush();
1838 
1839     Parser.Lex();
1840     if (Parser.getTok().isNot(AsmToken::EndOfStatement))
1841       return Error(Parser.getTok().getLoc(),
1842                    "unexpected token, expected end of statement");
1843 
1844     pushFeatureBits();
1845     return false;
1846   }
1847 
1848   if (Option == "pop") {
1849     SMLoc StartLoc = Parser.getTok().getLoc();
1850     getTargetStreamer().emitDirectiveOptionPop();
1851 
1852     Parser.Lex();
1853     if (Parser.getTok().isNot(AsmToken::EndOfStatement))
1854       return Error(Parser.getTok().getLoc(),
1855                    "unexpected token, expected end of statement");
1856 
1857     if (popFeatureBits())
1858       return Error(StartLoc, ".option pop with no .option push");
1859 
1860     return false;
1861   }
1862 
1863   if (Option == "rvc") {
1864     getTargetStreamer().emitDirectiveOptionRVC();
1865 
1866     Parser.Lex();
1867     if (Parser.getTok().isNot(AsmToken::EndOfStatement))
1868       return Error(Parser.getTok().getLoc(),
1869                    "unexpected token, expected end of statement");
1870 
1871     setFeatureBits(RISCV::FeatureStdExtC, "c");
1872     return false;
1873   }
1874 
1875   if (Option == "norvc") {
1876     getTargetStreamer().emitDirectiveOptionNoRVC();
1877 
1878     Parser.Lex();
1879     if (Parser.getTok().isNot(AsmToken::EndOfStatement))
1880       return Error(Parser.getTok().getLoc(),
1881                    "unexpected token, expected end of statement");
1882 
1883     clearFeatureBits(RISCV::FeatureStdExtC, "c");
1884     return false;
1885   }
1886 
1887   if (Option == "pic") {
1888     getTargetStreamer().emitDirectiveOptionPIC();
1889 
1890     Parser.Lex();
1891     if (Parser.getTok().isNot(AsmToken::EndOfStatement))
1892       return Error(Parser.getTok().getLoc(),
1893                    "unexpected token, expected end of statement");
1894 
1895     ParserOptions.IsPicEnabled = true;
1896     return false;
1897   }
1898 
1899   if (Option == "nopic") {
1900     getTargetStreamer().emitDirectiveOptionNoPIC();
1901 
1902     Parser.Lex();
1903     if (Parser.getTok().isNot(AsmToken::EndOfStatement))
1904       return Error(Parser.getTok().getLoc(),
1905                    "unexpected token, expected end of statement");
1906 
1907     ParserOptions.IsPicEnabled = false;
1908     return false;
1909   }
1910 
1911   if (Option == "relax") {
1912     getTargetStreamer().emitDirectiveOptionRelax();
1913 
1914     Parser.Lex();
1915     if (Parser.getTok().isNot(AsmToken::EndOfStatement))
1916       return Error(Parser.getTok().getLoc(),
1917                    "unexpected token, expected end of statement");
1918 
1919     setFeatureBits(RISCV::FeatureRelax, "relax");
1920     return false;
1921   }
1922 
1923   if (Option == "norelax") {
1924     getTargetStreamer().emitDirectiveOptionNoRelax();
1925 
1926     Parser.Lex();
1927     if (Parser.getTok().isNot(AsmToken::EndOfStatement))
1928       return Error(Parser.getTok().getLoc(),
1929                    "unexpected token, expected end of statement");
1930 
1931     clearFeatureBits(RISCV::FeatureRelax, "relax");
1932     return false;
1933   }
1934 
1935   // Unknown option.
1936   Warning(Parser.getTok().getLoc(),
1937           "unknown option, expected 'push', 'pop', 'rvc', 'norvc', 'relax' or "
1938           "'norelax'");
1939   Parser.eatToEndOfStatement();
1940   return false;
1941 }
1942 
1943 /// parseDirectiveAttribute
1944 ///  ::= .attribute expression ',' ( expression | "string" )
1945 ///  ::= .attribute identifier ',' ( expression | "string" )
1946 bool RISCVAsmParser::parseDirectiveAttribute() {
1947   MCAsmParser &Parser = getParser();
1948   int64_t Tag;
1949   SMLoc TagLoc;
1950   TagLoc = Parser.getTok().getLoc();
1951   if (Parser.getTok().is(AsmToken::Identifier)) {
1952     StringRef Name = Parser.getTok().getIdentifier();
1953     Optional<unsigned> Ret =
1954         ELFAttrs::attrTypeFromString(Name, RISCVAttrs::RISCVAttributeTags);
1955     if (!Ret.hasValue()) {
1956       Error(TagLoc, "attribute name not recognised: " + Name);
1957       return false;
1958     }
1959     Tag = Ret.getValue();
1960     Parser.Lex();
1961   } else {
1962     const MCExpr *AttrExpr;
1963 
1964     TagLoc = Parser.getTok().getLoc();
1965     if (Parser.parseExpression(AttrExpr))
1966       return true;
1967 
1968     const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(AttrExpr);
1969     if (check(!CE, TagLoc, "expected numeric constant"))
1970       return true;
1971 
1972     Tag = CE->getValue();
1973   }
1974 
1975   if (Parser.parseToken(AsmToken::Comma, "comma expected"))
1976     return true;
1977 
1978   StringRef StringValue;
1979   int64_t IntegerValue = 0;
1980   bool IsIntegerValue = true;
1981 
1982   // RISC-V attributes have a string value if the tag number is odd
1983   // and an integer value if the tag number is even.
1984   if (Tag % 2)
1985     IsIntegerValue = false;
1986 
1987   SMLoc ValueExprLoc = Parser.getTok().getLoc();
1988   if (IsIntegerValue) {
1989     const MCExpr *ValueExpr;
1990     if (Parser.parseExpression(ValueExpr))
1991       return true;
1992 
1993     const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(ValueExpr);
1994     if (!CE)
1995       return Error(ValueExprLoc, "expected numeric constant");
1996     IntegerValue = CE->getValue();
1997   } else {
1998     if (Parser.getTok().isNot(AsmToken::String))
1999       return Error(Parser.getTok().getLoc(), "expected string constant");
2000 
2001     StringValue = Parser.getTok().getStringContents();
2002     Parser.Lex();
2003   }
2004 
2005   if (Parser.parseToken(AsmToken::EndOfStatement,
2006                         "unexpected token in '.attribute' directive"))
2007     return true;
2008 
2009   if (Tag == RISCVAttrs::ARCH) {
2010     StringRef Arch = StringValue;
2011     if (Arch.consume_front("rv32"))
2012       clearFeatureBits(RISCV::Feature64Bit, "64bit");
2013     else if (Arch.consume_front("rv64"))
2014       setFeatureBits(RISCV::Feature64Bit, "64bit");
2015     else
2016       return Error(ValueExprLoc, "bad arch string " + Arch);
2017 
2018     while (!Arch.empty()) {
2019       if (Arch[0] == 'i')
2020         clearFeatureBits(RISCV::FeatureRV32E, "e");
2021       else if (Arch[0] == 'e')
2022         setFeatureBits(RISCV::FeatureRV32E, "e");
2023       else if (Arch[0] == 'g') {
2024         clearFeatureBits(RISCV::FeatureRV32E, "e");
2025         setFeatureBits(RISCV::FeatureStdExtM, "m");
2026         setFeatureBits(RISCV::FeatureStdExtA, "a");
2027         setFeatureBits(RISCV::FeatureStdExtF, "f");
2028         setFeatureBits(RISCV::FeatureStdExtD, "d");
2029       } else if (Arch[0] == 'm')
2030         setFeatureBits(RISCV::FeatureStdExtM, "m");
2031       else if (Arch[0] == 'a')
2032         setFeatureBits(RISCV::FeatureStdExtA, "a");
2033       else if (Arch[0] == 'f')
2034         setFeatureBits(RISCV::FeatureStdExtF, "f");
2035       else if (Arch[0] == 'd') {
2036         setFeatureBits(RISCV::FeatureStdExtF, "f");
2037         setFeatureBits(RISCV::FeatureStdExtD, "d");
2038       } else if (Arch[0] == 'c') {
2039         setFeatureBits(RISCV::FeatureStdExtC, "c");
2040       } else
2041         return Error(ValueExprLoc, "bad arch string " + Arch);
2042 
2043       Arch = Arch.drop_front(1);
2044       int major = 0;
2045       int minor = 0;
2046       Arch.consumeInteger(10, major);
2047       Arch.consume_front("p");
2048       Arch.consumeInteger(10, minor);
2049       if (major != 0 || minor != 0) {
2050         Arch = Arch.drop_until([](char c) { return c == '_' || c == '"'; });
2051         Arch = Arch.drop_while([](char c) { return c == '_'; });
2052       }
2053     }
2054   }
2055 
2056   if (IsIntegerValue)
2057     getTargetStreamer().emitAttribute(Tag, IntegerValue);
2058   else {
2059     if (Tag != RISCVAttrs::ARCH) {
2060       getTargetStreamer().emitTextAttribute(Tag, StringValue);
2061     } else {
2062       std::string formalArchStr = "rv32";
2063       if (getFeatureBits(RISCV::Feature64Bit))
2064         formalArchStr = "rv64";
2065       if (getFeatureBits(RISCV::FeatureRV32E))
2066         formalArchStr = (Twine(formalArchStr) + "e1p9").str();
2067       else
2068         formalArchStr = (Twine(formalArchStr) + "i2p0").str();
2069 
2070       if (getFeatureBits(RISCV::FeatureStdExtM))
2071         formalArchStr = (Twine(formalArchStr) + "_m2p0").str();
2072       if (getFeatureBits(RISCV::FeatureStdExtA))
2073         formalArchStr = (Twine(formalArchStr) + "_a2p0").str();
2074       if (getFeatureBits(RISCV::FeatureStdExtF))
2075         formalArchStr = (Twine(formalArchStr) + "_f2p0").str();
2076       if (getFeatureBits(RISCV::FeatureStdExtD))
2077         formalArchStr = (Twine(formalArchStr) + "_d2p0").str();
2078       if (getFeatureBits(RISCV::FeatureStdExtC))
2079         formalArchStr = (Twine(formalArchStr) + "_c2p0").str();
2080 
2081       getTargetStreamer().emitTextAttribute(Tag, formalArchStr);
2082     }
2083   }
2084 
2085   return false;
2086 }
2087 
2088 void RISCVAsmParser::emitToStreamer(MCStreamer &S, const MCInst &Inst) {
2089   MCInst CInst;
2090   bool Res = compressInst(CInst, Inst, getSTI(), S.getContext());
2091   if (Res)
2092     ++RISCVNumInstrsCompressed;
2093   S.emitInstruction((Res ? CInst : Inst), getSTI());
2094 }
2095 
2096 void RISCVAsmParser::emitLoadImm(MCRegister DestReg, int64_t Value,
2097                                  MCStreamer &Out) {
2098   RISCVMatInt::InstSeq Seq;
2099   RISCVMatInt::generateInstSeq(Value, isRV64(), Seq);
2100 
2101   MCRegister SrcReg = RISCV::X0;
2102   for (RISCVMatInt::Inst &Inst : Seq) {
2103     if (Inst.Opc == RISCV::LUI) {
2104       emitToStreamer(
2105           Out, MCInstBuilder(RISCV::LUI).addReg(DestReg).addImm(Inst.Imm));
2106     } else {
2107       emitToStreamer(
2108           Out, MCInstBuilder(Inst.Opc).addReg(DestReg).addReg(SrcReg).addImm(
2109                    Inst.Imm));
2110     }
2111 
2112     // Only the first instruction has X0 as its source.
2113     SrcReg = DestReg;
2114   }
2115 }
2116 
2117 void RISCVAsmParser::emitAuipcInstPair(MCOperand DestReg, MCOperand TmpReg,
2118                                        const MCExpr *Symbol,
2119                                        RISCVMCExpr::VariantKind VKHi,
2120                                        unsigned SecondOpcode, SMLoc IDLoc,
2121                                        MCStreamer &Out) {
2122   // A pair of instructions for PC-relative addressing; expands to
2123   //   TmpLabel: AUIPC TmpReg, VKHi(symbol)
2124   //             OP DestReg, TmpReg, %pcrel_lo(TmpLabel)
2125   MCContext &Ctx = getContext();
2126 
2127   MCSymbol *TmpLabel = Ctx.createTempSymbol(
2128       "pcrel_hi", /* AlwaysAddSuffix */ true, /* CanBeUnnamed */ false);
2129   Out.emitLabel(TmpLabel);
2130 
2131   const RISCVMCExpr *SymbolHi = RISCVMCExpr::create(Symbol, VKHi, Ctx);
2132   emitToStreamer(
2133       Out, MCInstBuilder(RISCV::AUIPC).addOperand(TmpReg).addExpr(SymbolHi));
2134 
2135   const MCExpr *RefToLinkTmpLabel =
2136       RISCVMCExpr::create(MCSymbolRefExpr::create(TmpLabel, Ctx),
2137                           RISCVMCExpr::VK_RISCV_PCREL_LO, Ctx);
2138 
2139   emitToStreamer(Out, MCInstBuilder(SecondOpcode)
2140                           .addOperand(DestReg)
2141                           .addOperand(TmpReg)
2142                           .addExpr(RefToLinkTmpLabel));
2143 }
2144 
2145 void RISCVAsmParser::emitLoadLocalAddress(MCInst &Inst, SMLoc IDLoc,
2146                                           MCStreamer &Out) {
2147   // The load local address pseudo-instruction "lla" is used in PC-relative
2148   // addressing of local symbols:
2149   //   lla rdest, symbol
2150   // expands to
2151   //   TmpLabel: AUIPC rdest, %pcrel_hi(symbol)
2152   //             ADDI rdest, rdest, %pcrel_lo(TmpLabel)
2153   MCOperand DestReg = Inst.getOperand(0);
2154   const MCExpr *Symbol = Inst.getOperand(1).getExpr();
2155   emitAuipcInstPair(DestReg, DestReg, Symbol, RISCVMCExpr::VK_RISCV_PCREL_HI,
2156                     RISCV::ADDI, IDLoc, Out);
2157 }
2158 
2159 void RISCVAsmParser::emitLoadAddress(MCInst &Inst, SMLoc IDLoc,
2160                                      MCStreamer &Out) {
2161   // The load address pseudo-instruction "la" is used in PC-relative and
2162   // GOT-indirect addressing of global symbols:
2163   //   la rdest, symbol
2164   // expands to either (for non-PIC)
2165   //   TmpLabel: AUIPC rdest, %pcrel_hi(symbol)
2166   //             ADDI rdest, rdest, %pcrel_lo(TmpLabel)
2167   // or (for PIC)
2168   //   TmpLabel: AUIPC rdest, %got_pcrel_hi(symbol)
2169   //             Lx rdest, %pcrel_lo(TmpLabel)(rdest)
2170   MCOperand DestReg = Inst.getOperand(0);
2171   const MCExpr *Symbol = Inst.getOperand(1).getExpr();
2172   unsigned SecondOpcode;
2173   RISCVMCExpr::VariantKind VKHi;
2174   if (ParserOptions.IsPicEnabled) {
2175     SecondOpcode = isRV64() ? RISCV::LD : RISCV::LW;
2176     VKHi = RISCVMCExpr::VK_RISCV_GOT_HI;
2177   } else {
2178     SecondOpcode = RISCV::ADDI;
2179     VKHi = RISCVMCExpr::VK_RISCV_PCREL_HI;
2180   }
2181   emitAuipcInstPair(DestReg, DestReg, Symbol, VKHi, SecondOpcode, IDLoc, Out);
2182 }
2183 
2184 void RISCVAsmParser::emitLoadTLSIEAddress(MCInst &Inst, SMLoc IDLoc,
2185                                           MCStreamer &Out) {
2186   // The load TLS IE address pseudo-instruction "la.tls.ie" is used in
2187   // initial-exec TLS model addressing of global symbols:
2188   //   la.tls.ie rdest, symbol
2189   // expands to
2190   //   TmpLabel: AUIPC rdest, %tls_ie_pcrel_hi(symbol)
2191   //             Lx rdest, %pcrel_lo(TmpLabel)(rdest)
2192   MCOperand DestReg = Inst.getOperand(0);
2193   const MCExpr *Symbol = Inst.getOperand(1).getExpr();
2194   unsigned SecondOpcode = isRV64() ? RISCV::LD : RISCV::LW;
2195   emitAuipcInstPair(DestReg, DestReg, Symbol, RISCVMCExpr::VK_RISCV_TLS_GOT_HI,
2196                     SecondOpcode, IDLoc, Out);
2197 }
2198 
2199 void RISCVAsmParser::emitLoadTLSGDAddress(MCInst &Inst, SMLoc IDLoc,
2200                                           MCStreamer &Out) {
2201   // The load TLS GD address pseudo-instruction "la.tls.gd" is used in
2202   // global-dynamic TLS model addressing of global symbols:
2203   //   la.tls.gd rdest, symbol
2204   // expands to
2205   //   TmpLabel: AUIPC rdest, %tls_gd_pcrel_hi(symbol)
2206   //             ADDI rdest, rdest, %pcrel_lo(TmpLabel)
2207   MCOperand DestReg = Inst.getOperand(0);
2208   const MCExpr *Symbol = Inst.getOperand(1).getExpr();
2209   emitAuipcInstPair(DestReg, DestReg, Symbol, RISCVMCExpr::VK_RISCV_TLS_GD_HI,
2210                     RISCV::ADDI, IDLoc, Out);
2211 }
2212 
2213 void RISCVAsmParser::emitLoadStoreSymbol(MCInst &Inst, unsigned Opcode,
2214                                          SMLoc IDLoc, MCStreamer &Out,
2215                                          bool HasTmpReg) {
2216   // The load/store pseudo-instruction does a pc-relative load with
2217   // a symbol.
2218   //
2219   // The expansion looks like this
2220   //
2221   //   TmpLabel: AUIPC tmp, %pcrel_hi(symbol)
2222   //             [S|L]X    rd, %pcrel_lo(TmpLabel)(tmp)
2223   MCOperand DestReg = Inst.getOperand(0);
2224   unsigned SymbolOpIdx = HasTmpReg ? 2 : 1;
2225   unsigned TmpRegOpIdx = HasTmpReg ? 1 : 0;
2226   MCOperand TmpReg = Inst.getOperand(TmpRegOpIdx);
2227   const MCExpr *Symbol = Inst.getOperand(SymbolOpIdx).getExpr();
2228   emitAuipcInstPair(DestReg, TmpReg, Symbol, RISCVMCExpr::VK_RISCV_PCREL_HI,
2229                     Opcode, IDLoc, Out);
2230 }
2231 
2232 void RISCVAsmParser::emitPseudoExtend(MCInst &Inst, bool SignExtend,
2233                                       int64_t Width, SMLoc IDLoc,
2234                                       MCStreamer &Out) {
2235   // The sign/zero extend pseudo-instruction does two shifts, with the shift
2236   // amounts dependent on the XLEN.
2237   //
2238   // The expansion looks like this
2239   //
2240   //    SLLI rd, rs, XLEN - Width
2241   //    SR[A|R]I rd, rd, XLEN - Width
2242   MCOperand DestReg = Inst.getOperand(0);
2243   MCOperand SourceReg = Inst.getOperand(1);
2244 
2245   unsigned SecondOpcode = SignExtend ? RISCV::SRAI : RISCV::SRLI;
2246   int64_t ShAmt = (isRV64() ? 64 : 32) - Width;
2247 
2248   assert(ShAmt > 0 && "Shift amount must be non-zero.");
2249 
2250   emitToStreamer(Out, MCInstBuilder(RISCV::SLLI)
2251                           .addOperand(DestReg)
2252                           .addOperand(SourceReg)
2253                           .addImm(ShAmt));
2254 
2255   emitToStreamer(Out, MCInstBuilder(SecondOpcode)
2256                           .addOperand(DestReg)
2257                           .addOperand(DestReg)
2258                           .addImm(ShAmt));
2259 }
2260 
2261 bool RISCVAsmParser::checkPseudoAddTPRel(MCInst &Inst,
2262                                          OperandVector &Operands) {
2263   assert(Inst.getOpcode() == RISCV::PseudoAddTPRel && "Invalid instruction");
2264   assert(Inst.getOperand(2).isReg() && "Unexpected second operand kind");
2265   if (Inst.getOperand(2).getReg() != RISCV::X4) {
2266     SMLoc ErrorLoc = ((RISCVOperand &)*Operands[3]).getStartLoc();
2267     return Error(ErrorLoc, "the second input operand must be tp/x4 when using "
2268                            "%tprel_add modifier");
2269   }
2270 
2271   return false;
2272 }
2273 
2274 std::unique_ptr<RISCVOperand> RISCVAsmParser::defaultMaskRegOp() const {
2275   return RISCVOperand::createReg(RISCV::NoRegister, llvm::SMLoc(),
2276                                  llvm::SMLoc(), isRV64());
2277 }
2278 
2279 bool RISCVAsmParser::validateInstruction(MCInst &Inst,
2280                                          OperandVector &Operands) {
2281   const MCInstrDesc &MCID = MII.get(Inst.getOpcode());
2282   unsigned TargetFlags =
2283       (MCID.TSFlags >> RISCVII::ConstraintOffset) & RISCVII::ConstraintMask;
2284   if (TargetFlags == RISCVII::NoConstraint)
2285     return false;
2286 
2287   unsigned DestReg = Inst.getOperand(0).getReg();
2288   unsigned CheckReg;
2289   // Operands[1] will be the first operand, DestReg.
2290   SMLoc Loc = Operands[1]->getStartLoc();
2291   if (TargetFlags & RISCVII::VS2Constraint) {
2292     CheckReg = Inst.getOperand(1).getReg();
2293     if (DestReg == CheckReg)
2294       return Error(Loc, "The destination vector register group cannot overlap"
2295                         " the source vector register group.");
2296   }
2297   if ((TargetFlags & RISCVII::VS1Constraint) && (Inst.getOperand(2).isReg())) {
2298     CheckReg = Inst.getOperand(2).getReg();
2299     if (DestReg == CheckReg)
2300       return Error(Loc, "The destination vector register group cannot overlap"
2301                         " the source vector register group.");
2302   }
2303   if ((TargetFlags & RISCVII::VMConstraint) && (DestReg == RISCV::V0)) {
2304     // vadc, vsbc are special cases. These instructions have no mask register.
2305     // The destination register could not be V0.
2306     unsigned Opcode = Inst.getOpcode();
2307     if (Opcode == RISCV::VADC_VVM || Opcode == RISCV::VADC_VXM ||
2308         Opcode == RISCV::VADC_VIM || Opcode == RISCV::VSBC_VVM ||
2309         Opcode == RISCV::VSBC_VXM || Opcode == RISCV::VFMERGE_VFM ||
2310         Opcode == RISCV::VMERGE_VIM || Opcode == RISCV::VMERGE_VVM ||
2311         Opcode == RISCV::VMERGE_VXM)
2312       return Error(Loc, "The destination vector register group cannot be V0.");
2313 
2314     // Regardless masked or unmasked version, the number of operands is the
2315     // same. For example, "viota.m v0, v2" is "viota.m v0, v2, NoRegister"
2316     // actually. We need to check the last operand to ensure whether it is
2317     // masked or not.
2318     if ((TargetFlags & RISCVII::OneInput) && (Inst.getNumOperands() == 3))
2319       CheckReg = Inst.getOperand(2).getReg();
2320     else if (Inst.getNumOperands() == 4)
2321       CheckReg = Inst.getOperand(3).getReg();
2322     if (DestReg == CheckReg)
2323       return Error(Loc, "The destination vector register group cannot overlap"
2324                         " the mask register.");
2325   }
2326   return false;
2327 }
2328 
2329 bool RISCVAsmParser::processInstruction(MCInst &Inst, SMLoc IDLoc,
2330                                         OperandVector &Operands,
2331                                         MCStreamer &Out) {
2332   Inst.setLoc(IDLoc);
2333 
2334   switch (Inst.getOpcode()) {
2335   default:
2336     break;
2337   case RISCV::PseudoLI: {
2338     MCRegister Reg = Inst.getOperand(0).getReg();
2339     const MCOperand &Op1 = Inst.getOperand(1);
2340     if (Op1.isExpr()) {
2341       // We must have li reg, %lo(sym) or li reg, %pcrel_lo(sym) or similar.
2342       // Just convert to an addi. This allows compatibility with gas.
2343       emitToStreamer(Out, MCInstBuilder(RISCV::ADDI)
2344                               .addReg(Reg)
2345                               .addReg(RISCV::X0)
2346                               .addExpr(Op1.getExpr()));
2347       return false;
2348     }
2349     int64_t Imm = Inst.getOperand(1).getImm();
2350     // On RV32 the immediate here can either be a signed or an unsigned
2351     // 32-bit number. Sign extension has to be performed to ensure that Imm
2352     // represents the expected signed 64-bit number.
2353     if (!isRV64())
2354       Imm = SignExtend64<32>(Imm);
2355     emitLoadImm(Reg, Imm, Out);
2356     return false;
2357   }
2358   case RISCV::PseudoLLA:
2359     emitLoadLocalAddress(Inst, IDLoc, Out);
2360     return false;
2361   case RISCV::PseudoLA:
2362     emitLoadAddress(Inst, IDLoc, Out);
2363     return false;
2364   case RISCV::PseudoLA_TLS_IE:
2365     emitLoadTLSIEAddress(Inst, IDLoc, Out);
2366     return false;
2367   case RISCV::PseudoLA_TLS_GD:
2368     emitLoadTLSGDAddress(Inst, IDLoc, Out);
2369     return false;
2370   case RISCV::PseudoLB:
2371     emitLoadStoreSymbol(Inst, RISCV::LB, IDLoc, Out, /*HasTmpReg=*/false);
2372     return false;
2373   case RISCV::PseudoLBU:
2374     emitLoadStoreSymbol(Inst, RISCV::LBU, IDLoc, Out, /*HasTmpReg=*/false);
2375     return false;
2376   case RISCV::PseudoLH:
2377     emitLoadStoreSymbol(Inst, RISCV::LH, IDLoc, Out, /*HasTmpReg=*/false);
2378     return false;
2379   case RISCV::PseudoLHU:
2380     emitLoadStoreSymbol(Inst, RISCV::LHU, IDLoc, Out, /*HasTmpReg=*/false);
2381     return false;
2382   case RISCV::PseudoLW:
2383     emitLoadStoreSymbol(Inst, RISCV::LW, IDLoc, Out, /*HasTmpReg=*/false);
2384     return false;
2385   case RISCV::PseudoLWU:
2386     emitLoadStoreSymbol(Inst, RISCV::LWU, IDLoc, Out, /*HasTmpReg=*/false);
2387     return false;
2388   case RISCV::PseudoLD:
2389     emitLoadStoreSymbol(Inst, RISCV::LD, IDLoc, Out, /*HasTmpReg=*/false);
2390     return false;
2391   case RISCV::PseudoFLH:
2392     emitLoadStoreSymbol(Inst, RISCV::FLH, IDLoc, Out, /*HasTmpReg=*/true);
2393     return false;
2394   case RISCV::PseudoFLW:
2395     emitLoadStoreSymbol(Inst, RISCV::FLW, IDLoc, Out, /*HasTmpReg=*/true);
2396     return false;
2397   case RISCV::PseudoFLD:
2398     emitLoadStoreSymbol(Inst, RISCV::FLD, IDLoc, Out, /*HasTmpReg=*/true);
2399     return false;
2400   case RISCV::PseudoSB:
2401     emitLoadStoreSymbol(Inst, RISCV::SB, IDLoc, Out, /*HasTmpReg=*/true);
2402     return false;
2403   case RISCV::PseudoSH:
2404     emitLoadStoreSymbol(Inst, RISCV::SH, IDLoc, Out, /*HasTmpReg=*/true);
2405     return false;
2406   case RISCV::PseudoSW:
2407     emitLoadStoreSymbol(Inst, RISCV::SW, IDLoc, Out, /*HasTmpReg=*/true);
2408     return false;
2409   case RISCV::PseudoSD:
2410     emitLoadStoreSymbol(Inst, RISCV::SD, IDLoc, Out, /*HasTmpReg=*/true);
2411     return false;
2412   case RISCV::PseudoFSH:
2413     emitLoadStoreSymbol(Inst, RISCV::FSH, IDLoc, Out, /*HasTmpReg=*/true);
2414     return false;
2415   case RISCV::PseudoFSW:
2416     emitLoadStoreSymbol(Inst, RISCV::FSW, IDLoc, Out, /*HasTmpReg=*/true);
2417     return false;
2418   case RISCV::PseudoFSD:
2419     emitLoadStoreSymbol(Inst, RISCV::FSD, IDLoc, Out, /*HasTmpReg=*/true);
2420     return false;
2421   case RISCV::PseudoAddTPRel:
2422     if (checkPseudoAddTPRel(Inst, Operands))
2423       return true;
2424     break;
2425   case RISCV::PseudoSEXT_B:
2426     emitPseudoExtend(Inst, /*SignExtend=*/true, /*Width=*/8, IDLoc, Out);
2427     return false;
2428   case RISCV::PseudoSEXT_H:
2429     emitPseudoExtend(Inst, /*SignExtend=*/true, /*Width=*/16, IDLoc, Out);
2430     return false;
2431   case RISCV::PseudoZEXT_H:
2432     emitPseudoExtend(Inst, /*SignExtend=*/false, /*Width=*/16, IDLoc, Out);
2433     return false;
2434   case RISCV::PseudoZEXT_W:
2435     emitPseudoExtend(Inst, /*SignExtend=*/false, /*Width=*/32, IDLoc, Out);
2436     return false;
2437   }
2438 
2439   emitToStreamer(Out, Inst);
2440   return false;
2441 }
2442 
2443 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeRISCVAsmParser() {
2444   RegisterMCAsmParser<RISCVAsmParser> X(getTheRISCV32Target());
2445   RegisterMCAsmParser<RISCVAsmParser> Y(getTheRISCV64Target());
2446 }
2447