1 //===- MILexer.cpp - Machine instructions lexer implementation ----------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the lexing of machine instructions.
12 //===----------------------------------------------------------------------===//
15 #include "llvm/ADT/StringExtras.h"
16 #include "llvm/ADT/StringSwitch.h"
17 #include "llvm/ADT/Twine.h"
24 /// This class provides a way to iterate and get characters from the source
31 Cursor(NoneType) : Ptr(nullptr), End(nullptr) {}
33 explicit Cursor(StringRef Str) {
35 End = Ptr + Str.size();
38 bool isEOF() const { return Ptr == End; }
40 char peek(int I = 0) const { return End - Ptr <= I ? 0 : Ptr[I]; }
42 void advance(unsigned I = 1) { Ptr += I; }
44 StringRef remaining() const { return StringRef(Ptr, End - Ptr); }
46 StringRef upto(Cursor C) const {
47 assert(C.Ptr >= Ptr && C.Ptr <= End);
48 return StringRef(Ptr, C.Ptr - Ptr);
51 StringRef::iterator location() const { return Ptr; }
53 operator bool() const { return Ptr != nullptr; }
56 } // end anonymous namespace
58 /// Skip the leading whitespace characters and return the updated cursor.
59 static Cursor skipWhitespace(Cursor C) {
60 while (isspace(C.peek()))
65 /// Return true if the given character satisfies the following regular
66 /// expression: [-a-zA-Z$._0-9]
67 static bool isIdentifierChar(char C) {
68 return isalpha(C) || isdigit(C) || C == '_' || C == '-' || C == '.' ||
72 /// Unescapes the given string value.
74 /// Expects the string value to be quoted.
75 static std::string unescapeQuotedString(StringRef Value) {
76 assert(Value.front() == '"' && Value.back() == '"');
77 Cursor C = Cursor(Value.substr(1, Value.size() - 2));
80 Str.reserve(C.remaining().size());
84 if (C.peek(1) == '\\') {
90 if (isxdigit(C.peek(1)) && isxdigit(C.peek(2))) {
91 Str += hexDigitValue(C.peek(1)) * 16 + hexDigitValue(C.peek(2));
102 /// Lex a string constant using the following regular expression: \"[^\"]*\"
103 static Cursor lexStringConstant(
105 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
106 assert(C.peek() == '"');
107 for (C.advance(); C.peek() != '"'; C.advance()) {
111 "end of machine instruction reached before the closing '\"'");
119 static Cursor lexName(
120 Cursor C, MIToken &Token, MIToken::TokenKind Type, unsigned PrefixLength,
121 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
123 C.advance(PrefixLength);
124 if (C.peek() == '"') {
125 if (Cursor R = lexStringConstant(C, ErrorCallback)) {
126 StringRef String = Range.upto(R);
127 Token = MIToken(Type, String,
128 unescapeQuotedString(String.drop_front(PrefixLength)),
132 Token = MIToken(MIToken::Error, Range.remaining());
135 while (isIdentifierChar(C.peek()))
137 Token = MIToken(Type, Range.upto(C), PrefixLength);
141 static Cursor maybeLexIntegerType(Cursor C, MIToken &Token) {
142 if (C.peek() != 'i' || !isdigit(C.peek(1)))
145 C.advance(); // Skip 'i'
146 while (isdigit(C.peek()))
148 Token = MIToken(MIToken::IntegerType, Range.upto(C));
152 static MIToken::TokenKind getIdentifierKind(StringRef Identifier) {
153 return StringSwitch<MIToken::TokenKind>(Identifier)
154 .Case("_", MIToken::underscore)
155 .Case("implicit", MIToken::kw_implicit)
156 .Case("implicit-def", MIToken::kw_implicit_define)
157 .Case("dead", MIToken::kw_dead)
158 .Case("killed", MIToken::kw_killed)
159 .Case("undef", MIToken::kw_undef)
160 .Case("early-clobber", MIToken::kw_early_clobber)
161 .Case("debug-use", MIToken::kw_debug_use)
162 .Case("frame-setup", MIToken::kw_frame_setup)
163 .Case("debug-location", MIToken::kw_debug_location)
164 .Case(".cfi_offset", MIToken::kw_cfi_offset)
165 .Case(".cfi_def_cfa_register", MIToken::kw_cfi_def_cfa_register)
166 .Case(".cfi_def_cfa_offset", MIToken::kw_cfi_def_cfa_offset)
167 .Case(".cfi_def_cfa", MIToken::kw_cfi_def_cfa)
168 .Case("blockaddress", MIToken::kw_blockaddress)
169 .Case("target-index", MIToken::kw_target_index)
170 .Case("half", MIToken::kw_half)
171 .Case("float", MIToken::kw_float)
172 .Case("double", MIToken::kw_double)
173 .Case("x86_fp80", MIToken::kw_x86_fp80)
174 .Case("fp128", MIToken::kw_fp128)
175 .Case("ppc_fp128", MIToken::kw_ppc_fp128)
176 .Case("target-flags", MIToken::kw_target_flags)
177 .Case("volatile", MIToken::kw_volatile)
178 .Default(MIToken::Identifier);
181 static Cursor maybeLexIdentifier(Cursor C, MIToken &Token) {
182 if (!isalpha(C.peek()) && C.peek() != '_' && C.peek() != '.')
185 while (isIdentifierChar(C.peek()))
187 auto Identifier = Range.upto(C);
188 Token = MIToken(getIdentifierKind(Identifier), Identifier);
192 static Cursor maybeLexMachineBasicBlock(
193 Cursor C, MIToken &Token,
194 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
195 if (!C.remaining().startswith("%bb."))
198 C.advance(4); // Skip '%bb.'
199 if (!isdigit(C.peek())) {
200 Token = MIToken(MIToken::Error, C.remaining());
201 ErrorCallback(C.location(), "expected a number after '%bb.'");
204 auto NumberRange = C;
205 while (isdigit(C.peek()))
207 StringRef Number = NumberRange.upto(C);
208 unsigned StringOffset = 4 + Number.size(); // Drop '%bb.<id>'
209 if (C.peek() == '.') {
210 C.advance(); // Skip '.'
212 while (isIdentifierChar(C.peek()))
215 Token = MIToken(MIToken::MachineBasicBlock, Range.upto(C), APSInt(Number),
220 static Cursor maybeLexIndex(Cursor C, MIToken &Token, StringRef Rule,
221 MIToken::TokenKind Kind) {
222 if (!C.remaining().startswith(Rule) || !isdigit(C.peek(Rule.size())))
225 C.advance(Rule.size());
226 auto NumberRange = C;
227 while (isdigit(C.peek()))
229 Token = MIToken(Kind, Range.upto(C), APSInt(NumberRange.upto(C)));
233 static Cursor maybeLexIndexAndName(Cursor C, MIToken &Token, StringRef Rule,
234 MIToken::TokenKind Kind) {
235 if (!C.remaining().startswith(Rule) || !isdigit(C.peek(Rule.size())))
238 C.advance(Rule.size());
239 auto NumberRange = C;
240 while (isdigit(C.peek()))
242 StringRef Number = NumberRange.upto(C);
243 unsigned StringOffset = Rule.size() + Number.size();
244 if (C.peek() == '.') {
247 while (isIdentifierChar(C.peek()))
250 Token = MIToken(Kind, Range.upto(C), APSInt(Number), StringOffset);
254 static Cursor maybeLexJumpTableIndex(Cursor C, MIToken &Token) {
255 return maybeLexIndex(C, Token, "%jump-table.", MIToken::JumpTableIndex);
258 static Cursor maybeLexStackObject(Cursor C, MIToken &Token) {
259 return maybeLexIndexAndName(C, Token, "%stack.", MIToken::StackObject);
262 static Cursor maybeLexFixedStackObject(Cursor C, MIToken &Token) {
263 return maybeLexIndex(C, Token, "%fixed-stack.", MIToken::FixedStackObject);
266 static Cursor maybeLexConstantPoolItem(Cursor C, MIToken &Token) {
267 return maybeLexIndex(C, Token, "%const.", MIToken::ConstantPoolItem);
270 static Cursor maybeLexIRBlock(
271 Cursor C, MIToken &Token,
272 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
273 const StringRef Rule = "%ir-block.";
274 if (!C.remaining().startswith(Rule))
276 if (isdigit(C.peek(Rule.size())))
277 return maybeLexIndex(C, Token, Rule, MIToken::IRBlock);
278 return lexName(C, Token, MIToken::NamedIRBlock, Rule.size(), ErrorCallback);
281 static Cursor maybeLexIRValue(
282 Cursor C, MIToken &Token,
283 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
284 const StringRef Rule = "%ir.";
285 if (!C.remaining().startswith(Rule))
287 return lexName(C, Token, MIToken::NamedIRValue, Rule.size(), ErrorCallback);
290 static Cursor lexVirtualRegister(Cursor C, MIToken &Token) {
292 C.advance(); // Skip '%'
293 auto NumberRange = C;
294 while (isdigit(C.peek()))
296 Token = MIToken(MIToken::VirtualRegister, Range.upto(C),
297 APSInt(NumberRange.upto(C)));
301 static Cursor maybeLexRegister(Cursor C, MIToken &Token) {
304 if (isdigit(C.peek(1)))
305 return lexVirtualRegister(C, Token);
307 C.advance(); // Skip '%'
308 while (isIdentifierChar(C.peek()))
310 Token = MIToken(MIToken::NamedRegister, Range.upto(C),
311 /*StringOffset=*/1); // Drop the '%'
315 static Cursor maybeLexGlobalValue(
316 Cursor C, MIToken &Token,
317 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
320 if (!isdigit(C.peek(1)))
321 return lexName(C, Token, MIToken::NamedGlobalValue, /*PrefixLength=*/1,
324 C.advance(1); // Skip the '@'
325 auto NumberRange = C;
326 while (isdigit(C.peek()))
329 MIToken(MIToken::GlobalValue, Range.upto(C), APSInt(NumberRange.upto(C)));
333 static Cursor maybeLexExternalSymbol(
334 Cursor C, MIToken &Token,
335 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
338 return lexName(C, Token, MIToken::ExternalSymbol, /*PrefixLength=*/1,
342 static bool isValidHexFloatingPointPrefix(char C) {
343 return C == 'H' || C == 'K' || C == 'L' || C == 'M';
346 static Cursor maybeLexHexFloatingPointLiteral(Cursor C, MIToken &Token) {
347 if (C.peek() != '0' || C.peek(1) != 'x')
350 C.advance(2); // Skip '0x'
351 if (isValidHexFloatingPointPrefix(C.peek()))
353 while (isxdigit(C.peek()))
355 Token = MIToken(MIToken::FloatingPointLiteral, Range.upto(C));
359 static Cursor lexFloatingPointLiteral(Cursor Range, Cursor C, MIToken &Token) {
361 // Skip over [0-9]*([eE][-+]?[0-9]+)?
362 while (isdigit(C.peek()))
364 if ((C.peek() == 'e' || C.peek() == 'E') &&
365 (isdigit(C.peek(1)) ||
366 ((C.peek(1) == '-' || C.peek(1) == '+') && isdigit(C.peek(2))))) {
368 while (isdigit(C.peek()))
371 Token = MIToken(MIToken::FloatingPointLiteral, Range.upto(C));
375 static Cursor maybeLexNumericalLiteral(Cursor C, MIToken &Token) {
376 if (!isdigit(C.peek()) && (C.peek() != '-' || !isdigit(C.peek(1))))
380 while (isdigit(C.peek()))
383 return lexFloatingPointLiteral(Range, C, Token);
384 StringRef StrVal = Range.upto(C);
385 Token = MIToken(MIToken::IntegerLiteral, StrVal, APSInt(StrVal));
389 static MIToken::TokenKind symbolToken(char C) {
392 return MIToken::comma;
394 return MIToken::equal;
396 return MIToken::colon;
398 return MIToken::exclaim;
400 return MIToken::lparen;
402 return MIToken::rparen;
404 return MIToken::plus;
406 return MIToken::minus;
408 return MIToken::Error;
412 static Cursor maybeLexSymbol(Cursor C, MIToken &Token) {
413 MIToken::TokenKind Kind;
415 if (C.peek() == ':' && C.peek(1) == ':') {
416 Kind = MIToken::coloncolon;
419 Kind = symbolToken(C.peek());
420 if (Kind == MIToken::Error)
424 Token = MIToken(Kind, Range.upto(C));
428 StringRef llvm::lexMIToken(
429 StringRef Source, MIToken &Token,
430 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
431 auto C = skipWhitespace(Cursor(Source));
433 Token = MIToken(MIToken::Eof, C.remaining());
434 return C.remaining();
437 if (Cursor R = maybeLexIntegerType(C, Token))
438 return R.remaining();
439 if (Cursor R = maybeLexIdentifier(C, Token))
440 return R.remaining();
441 if (Cursor R = maybeLexMachineBasicBlock(C, Token, ErrorCallback))
442 return R.remaining();
443 if (Cursor R = maybeLexJumpTableIndex(C, Token))
444 return R.remaining();
445 if (Cursor R = maybeLexStackObject(C, Token))
446 return R.remaining();
447 if (Cursor R = maybeLexFixedStackObject(C, Token))
448 return R.remaining();
449 if (Cursor R = maybeLexConstantPoolItem(C, Token))
450 return R.remaining();
451 if (Cursor R = maybeLexIRBlock(C, Token, ErrorCallback))
452 return R.remaining();
453 if (Cursor R = maybeLexIRValue(C, Token, ErrorCallback))
454 return R.remaining();
455 if (Cursor R = maybeLexRegister(C, Token))
456 return R.remaining();
457 if (Cursor R = maybeLexGlobalValue(C, Token, ErrorCallback))
458 return R.remaining();
459 if (Cursor R = maybeLexExternalSymbol(C, Token, ErrorCallback))
460 return R.remaining();
461 if (Cursor R = maybeLexHexFloatingPointLiteral(C, Token))
462 return R.remaining();
463 if (Cursor R = maybeLexNumericalLiteral(C, Token))
464 return R.remaining();
465 if (Cursor R = maybeLexSymbol(C, Token))
466 return R.remaining();
468 Token = MIToken(MIToken::Error, C.remaining());
469 ErrorCallback(C.location(),
470 Twine("unexpected character '") + Twine(C.peek()) + "'");
471 return C.remaining();