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 void MIToken::unescapeQuotedStringValue(std::string &Str) const {
73 assert(isStringValueQuoted() && "String value isn't quoted");
74 StringRef Value = Range.drop_front(StringOffset);
75 assert(Value.front() == '"' && Value.back() == '"');
76 Cursor C = Cursor(Value.substr(1, Value.size() - 2));
79 Str.reserve(C.remaining().size());
83 if (C.peek(1) == '\\') {
89 if (isxdigit(C.peek(1)) && isxdigit(C.peek(2))) {
90 Str += hexDigitValue(C.peek(1)) * 16 + hexDigitValue(C.peek(2));
100 /// Lex a string constant using the following regular expression: \"[^\"]*\"
101 static Cursor lexStringConstant(
103 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
104 assert(C.peek() == '"');
105 for (C.advance(); C.peek() != '"'; C.advance()) {
109 "end of machine instruction reached before the closing '\"'");
117 static MIToken::TokenKind getIdentifierKind(StringRef Identifier) {
118 return StringSwitch<MIToken::TokenKind>(Identifier)
119 .Case("_", MIToken::underscore)
120 .Case("implicit", MIToken::kw_implicit)
121 .Case("implicit-def", MIToken::kw_implicit_define)
122 .Case("dead", MIToken::kw_dead)
123 .Case("killed", MIToken::kw_killed)
124 .Case("undef", MIToken::kw_undef)
125 .Case("frame-setup", MIToken::kw_frame_setup)
126 .Default(MIToken::Identifier);
129 static Cursor maybeLexIdentifier(Cursor C, MIToken &Token) {
130 if (!isalpha(C.peek()) && C.peek() != '_')
133 while (isIdentifierChar(C.peek()))
135 auto Identifier = Range.upto(C);
136 Token = MIToken(getIdentifierKind(Identifier), Identifier);
140 static Cursor maybeLexMachineBasicBlock(
141 Cursor C, MIToken &Token,
142 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
143 if (!C.remaining().startswith("%bb."))
146 C.advance(4); // Skip '%bb.'
147 if (!isdigit(C.peek())) {
148 Token = MIToken(MIToken::Error, C.remaining());
149 ErrorCallback(C.location(), "expected a number after '%bb.'");
152 auto NumberRange = C;
153 while (isdigit(C.peek()))
155 StringRef Number = NumberRange.upto(C);
156 unsigned StringOffset = 4 + Number.size(); // Drop '%bb.<id>'
157 if (C.peek() == '.') {
158 C.advance(); // Skip '.'
160 while (isIdentifierChar(C.peek()))
163 Token = MIToken(MIToken::MachineBasicBlock, Range.upto(C), APSInt(Number),
168 static Cursor maybeLexIndex(Cursor C, MIToken &Token, StringRef Rule,
169 MIToken::TokenKind Kind) {
170 if (!C.remaining().startswith(Rule) || !isdigit(C.peek(Rule.size())))
173 C.advance(Rule.size());
174 auto NumberRange = C;
175 while (isdigit(C.peek()))
177 Token = MIToken(Kind, Range.upto(C), APSInt(NumberRange.upto(C)));
181 static Cursor maybeLexIndexAndName(Cursor C, MIToken &Token, StringRef Rule,
182 MIToken::TokenKind Kind) {
183 if (!C.remaining().startswith(Rule) || !isdigit(C.peek(Rule.size())))
186 C.advance(Rule.size());
187 auto NumberRange = C;
188 while (isdigit(C.peek()))
190 StringRef Number = NumberRange.upto(C);
191 unsigned StringOffset = Rule.size() + Number.size();
192 if (C.peek() == '.') {
195 while (isIdentifierChar(C.peek()))
198 Token = MIToken(Kind, Range.upto(C), APSInt(Number), StringOffset);
202 static Cursor maybeLexJumpTableIndex(Cursor C, MIToken &Token) {
203 return maybeLexIndex(C, Token, "%jump-table.", MIToken::JumpTableIndex);
206 static Cursor maybeLexStackObject(Cursor C, MIToken &Token) {
207 return maybeLexIndexAndName(C, Token, "%stack.", MIToken::StackObject);
210 static Cursor maybeLexFixedStackObject(Cursor C, MIToken &Token) {
211 return maybeLexIndex(C, Token, "%fixed-stack.", MIToken::FixedStackObject);
214 static Cursor maybeLexConstantPoolItem(Cursor C, MIToken &Token) {
215 return maybeLexIndex(C, Token, "%const.", MIToken::ConstantPoolItem);
218 static Cursor lexVirtualRegister(Cursor C, MIToken &Token) {
220 C.advance(); // Skip '%'
221 auto NumberRange = C;
222 while (isdigit(C.peek()))
224 Token = MIToken(MIToken::VirtualRegister, Range.upto(C),
225 APSInt(NumberRange.upto(C)));
229 static Cursor maybeLexRegister(Cursor C, MIToken &Token) {
232 if (isdigit(C.peek(1)))
233 return lexVirtualRegister(C, Token);
235 C.advance(); // Skip '%'
236 while (isIdentifierChar(C.peek()))
238 Token = MIToken(MIToken::NamedRegister, Range.upto(C),
239 /*StringOffset=*/1); // Drop the '%'
243 static Cursor maybeLexGlobalValue(
244 Cursor C, MIToken &Token,
245 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
249 C.advance(); // Skip the '@'
250 if (C.peek() == '"') {
251 if (Cursor R = lexStringConstant(C, ErrorCallback)) {
252 Token = MIToken(MIToken::QuotedNamedGlobalValue, Range.upto(R),
253 /*StringOffset=*/1); // Drop the '@'
256 Token = MIToken(MIToken::Error, Range.remaining());
259 if (!isdigit(C.peek())) {
260 while (isIdentifierChar(C.peek()))
262 Token = MIToken(MIToken::NamedGlobalValue, Range.upto(C),
263 /*StringOffset=*/1); // Drop the '@'
266 auto NumberRange = C;
267 while (isdigit(C.peek()))
270 MIToken(MIToken::GlobalValue, Range.upto(C), APSInt(NumberRange.upto(C)));
274 static Cursor lexName(
275 Cursor C, MIToken &Token, MIToken::TokenKind Type,
276 MIToken::TokenKind QuotedType, unsigned PrefixLength,
277 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
279 C.advance(PrefixLength);
280 if (C.peek() == '"') {
281 if (Cursor R = lexStringConstant(C, ErrorCallback)) {
282 Token = MIToken(QuotedType, Range.upto(R), PrefixLength);
285 Token = MIToken(MIToken::Error, Range.remaining());
288 while (isIdentifierChar(C.peek()))
290 Token = MIToken(Type, Range.upto(C), PrefixLength);
294 static Cursor maybeLexExternalSymbol(
295 Cursor C, MIToken &Token,
296 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
299 return lexName(C, Token, MIToken::ExternalSymbol,
300 MIToken::QuotedExternalSymbol,
301 /*PrefixLength=*/1, ErrorCallback);
304 static Cursor maybeLexIntegerLiteral(Cursor C, MIToken &Token) {
305 if (!isdigit(C.peek()) && (C.peek() != '-' || !isdigit(C.peek(1))))
309 while (isdigit(C.peek()))
311 StringRef StrVal = Range.upto(C);
312 Token = MIToken(MIToken::IntegerLiteral, StrVal, APSInt(StrVal));
316 static MIToken::TokenKind symbolToken(char C) {
319 return MIToken::comma;
321 return MIToken::equal;
323 return MIToken::colon;
325 return MIToken::Error;
329 static Cursor maybeLexSymbol(Cursor C, MIToken &Token) {
330 auto Kind = symbolToken(C.peek());
331 if (Kind == MIToken::Error)
335 Token = MIToken(Kind, Range.upto(C));
339 StringRef llvm::lexMIToken(
340 StringRef Source, MIToken &Token,
341 function_ref<void(StringRef::iterator Loc, const Twine &)> ErrorCallback) {
342 auto C = skipWhitespace(Cursor(Source));
344 Token = MIToken(MIToken::Eof, C.remaining());
345 return C.remaining();
348 if (Cursor R = maybeLexIdentifier(C, Token))
349 return R.remaining();
350 if (Cursor R = maybeLexMachineBasicBlock(C, Token, ErrorCallback))
351 return R.remaining();
352 if (Cursor R = maybeLexJumpTableIndex(C, Token))
353 return R.remaining();
354 if (Cursor R = maybeLexStackObject(C, Token))
355 return R.remaining();
356 if (Cursor R = maybeLexFixedStackObject(C, Token))
357 return R.remaining();
358 if (Cursor R = maybeLexConstantPoolItem(C, Token))
359 return R.remaining();
360 if (Cursor R = maybeLexRegister(C, Token))
361 return R.remaining();
362 if (Cursor R = maybeLexGlobalValue(C, Token, ErrorCallback))
363 return R.remaining();
364 if (Cursor R = maybeLexExternalSymbol(C, Token, ErrorCallback))
365 return R.remaining();
366 if (Cursor R = maybeLexIntegerLiteral(C, Token))
367 return R.remaining();
368 if (Cursor R = maybeLexSymbol(C, Token))
369 return R.remaining();
371 Token = MIToken(MIToken::Error, C.remaining());
372 ErrorCallback(C.location(),
373 Twine("unexpected character '") + Twine(C.peek()) + "'");
374 return C.remaining();