LLVM 19.0.0git
TGLexer.h
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1//===- TGLexer.h - Lexer for TableGen Files ---------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This class represents the Lexer for tablegen files.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_LIB_TABLEGEN_TGLEXER_H
14#define LLVM_LIB_TABLEGEN_TGLEXER_H
15
16#include "llvm/ADT/StringRef.h"
17#include "llvm/ADT/StringSet.h"
19#include "llvm/Support/SMLoc.h"
20#include <cassert>
21#include <memory>
22#include <set>
23#include <string>
24#include <vector>
25
26namespace llvm {
27template <typename T> class ArrayRef;
28class SourceMgr;
29class Twine;
30
31namespace tgtok {
32enum TokKind {
33 // Markers
36
37 // Tokens with no info.
38 minus, // -
39 plus, // +
42 l_brace, // {
43 r_brace, // }
44 l_paren, // (
45 r_paren, // )
46 less, // <
47 greater, // >
48 colon, // :
49 semi, // ;
50 comma, // ,
51 dot, // .
52 equal, // =
54 paste, // #
55 dotdotdot, // ...
56
57 // Boolean literals.
60
61 // Integer value.
63
64 // Binary constant. Note that these are sized according to the number of
65 // bits given.
67
68 // Preprocessing tokens for internal usage by the lexer.
69 // They are never returned as a result of Lex().
75
76 // Reserved keywords. ('ElseKW' is named to distinguish it from the
77 // existing 'Else' that means the preprocessor #else.)
92
93 // Object start tokens.
108
109 // Bang operators.
162
163 // String valued tokens.
170};
171
172/// isBangOperator - Return true if this is a bang operator.
173static inline bool isBangOperator(tgtok::TokKind Kind) {
174 return tgtok::BANG_OPERATOR_FIRST <= Kind && Kind <= BANG_OPERATOR_LAST;
175}
176
177/// isObjectStart - Return true if this is a valid first token for a statement.
178static inline bool isObjectStart(tgtok::TokKind Kind) {
179 return tgtok::OBJECT_START_FIRST <= Kind && Kind <= OBJECT_START_LAST;
180}
181
182/// isStringValue - Return true if this is a string value.
183static inline bool isStringValue(tgtok::TokKind Kind) {
184 return tgtok::STRING_VALUE_FIRST <= Kind && Kind <= STRING_VALUE_LAST;
185}
186} // namespace tgtok
187
188/// TGLexer - TableGen Lexer class.
189class TGLexer {
190 SourceMgr &SrcMgr;
191
192 const char *CurPtr = nullptr;
193 StringRef CurBuf;
194
195 // Information about the current token.
196 const char *TokStart = nullptr;
198 std::string CurStrVal; // This is valid for Id, StrVal, VarName, CodeFragment
199 int64_t CurIntVal = 0; // This is valid for IntVal.
200
201 /// CurBuffer - This is the current buffer index we're lexing from as managed
202 /// by the SourceMgr object.
203 unsigned CurBuffer = 0;
204
205public:
206 typedef std::set<std::string> DependenciesSetTy;
207
208private:
209 /// Dependencies - This is the list of all included files.
210 DependenciesSetTy Dependencies;
211
212public:
213 TGLexer(SourceMgr &SrcMgr, ArrayRef<std::string> Macros);
214
216 return CurCode = LexToken(CurPtr == CurBuf.begin());
217 }
218
220 return Dependencies;
221 }
222
223 tgtok::TokKind getCode() const { return CurCode; }
224
225 const std::string &getCurStrVal() const {
226 assert(tgtok::isStringValue(CurCode) &&
227 "This token doesn't have a string value");
228 return CurStrVal;
229 }
230 int64_t getCurIntVal() const {
231 assert(CurCode == tgtok::IntVal && "This token isn't an integer");
232 return CurIntVal;
233 }
234 std::pair<int64_t, unsigned> getCurBinaryIntVal() const {
235 assert(CurCode == tgtok::BinaryIntVal &&
236 "This token isn't a binary integer");
237 return std::make_pair(CurIntVal, (CurPtr - TokStart)-2);
238 }
239
240 SMLoc getLoc() const;
241 SMRange getLocRange() const;
242
243private:
244 /// LexToken - Read the next token and return its code.
245 tgtok::TokKind LexToken(bool FileOrLineStart = false);
246
247 tgtok::TokKind ReturnError(SMLoc Loc, const Twine &Msg);
248 tgtok::TokKind ReturnError(const char *Loc, const Twine &Msg);
249
250 int getNextChar();
251 int peekNextChar(int Index) const;
252 void SkipBCPLComment();
253 bool SkipCComment();
254 tgtok::TokKind LexIdentifier();
255 bool LexInclude();
256 tgtok::TokKind LexString();
257 tgtok::TokKind LexVarName();
258 tgtok::TokKind LexNumber();
259 tgtok::TokKind LexBracket();
260 tgtok::TokKind LexExclaim();
261
262 // Process EOF encountered in LexToken().
263 // If EOF is met in an include file, then the method will update
264 // CurPtr, CurBuf and preprocessing include stack, and return true.
265 // If EOF is met in the top-level file, then the method will
266 // update and check the preprocessing include stack, and return false.
267 bool processEOF();
268
269 // *** Structures and methods for preprocessing support ***
270
271 // A set of macro names that are defined either via command line or
272 // by using:
273 // #define NAME
274 StringSet<> DefinedMacros;
275
276 // Each of #ifdef and #else directives has a descriptor associated
277 // with it.
278 //
279 // An ordered list of preprocessing controls defined by #ifdef/#else
280 // directives that are in effect currently is called preprocessing
281 // control stack. It is represented as a vector of PreprocessorControlDesc's.
282 //
283 // The control stack is updated according to the following rules:
284 //
285 // For each #ifdef we add an element to the control stack.
286 // For each #else we replace the top element with a descriptor
287 // with an inverted IsDefined value.
288 // For each #endif we pop the top element from the control stack.
289 //
290 // When CurPtr reaches the current buffer's end, the control stack
291 // must be empty, i.e. #ifdef and the corresponding #endif
292 // must be located in the same file.
293 struct PreprocessorControlDesc {
294 // Either tgtok::Ifdef or tgtok::Else.
295 tgtok::TokKind Kind;
296
297 // True, if the condition for this directive is true, false - otherwise.
298 // Examples:
299 // #ifdef NAME : true, if NAME is defined, false - otherwise.
300 // ...
301 // #else : false, if NAME is defined, true - otherwise.
302 bool IsDefined;
303
304 // Pointer into CurBuf to the beginning of the preprocessing directive
305 // word, e.g.:
306 // #ifdef NAME
307 // ^ - SrcPos
308 SMLoc SrcPos;
309 };
310
311 // We want to disallow code like this:
312 // file1.td:
313 // #define NAME
314 // #ifdef NAME
315 // include "file2.td"
316 // EOF
317 // file2.td:
318 // #endif
319 // EOF
320 //
321 // To do this, we clear the preprocessing control stack on entry
322 // to each of the included file. PrepIncludeStack is used to store
323 // preprocessing control stacks for the current file and all its
324 // parent files. The back() element is the preprocessing control
325 // stack for the current file.
326 std::vector<std::unique_ptr<std::vector<PreprocessorControlDesc>>>
327 PrepIncludeStack;
328
329 // Validate that the current preprocessing control stack is empty,
330 // since we are about to exit a file, and pop the include stack.
331 //
332 // If IncludeStackMustBeEmpty is true, the include stack must be empty
333 // after the popping, otherwise, the include stack must not be empty
334 // after the popping. Basically, the include stack must be empty
335 // only if we exit the "top-level" file (i.e. finish lexing).
336 //
337 // The method returns false, if the current preprocessing control stack
338 // is not empty (e.g. there is an unterminated #ifdef/#else),
339 // true - otherwise.
340 bool prepExitInclude(bool IncludeStackMustBeEmpty);
341
342 // Look ahead for a preprocessing directive starting from CurPtr. The caller
343 // must only call this method, if *(CurPtr - 1) is '#'. If the method matches
344 // a preprocessing directive word followed by a whitespace, then it returns
345 // one of the internal token kinds, i.e. Ifdef, Else, Endif, Define.
346 //
347 // CurPtr is not adjusted by this method.
348 tgtok::TokKind prepIsDirective() const;
349
350 // Given a preprocessing token kind, adjusts CurPtr to the end
351 // of the preprocessing directive word. Returns true, unless
352 // an unsupported token kind is passed in.
353 //
354 // We use look-ahead prepIsDirective() and prepEatPreprocessorDirective()
355 // to avoid adjusting CurPtr before we are sure that '#' is followed
356 // by a preprocessing directive. If it is not, then we fall back to
357 // tgtok::paste interpretation of '#'.
358 bool prepEatPreprocessorDirective(tgtok::TokKind Kind);
359
360 // The main "exit" point from the token parsing to preprocessor.
361 //
362 // The method is called for CurPtr, when prepIsDirective() returns
363 // true. The first parameter matches the result of prepIsDirective(),
364 // denoting the actual preprocessor directive to be processed.
365 //
366 // If the preprocessing directive disables the tokens processing, e.g.:
367 // #ifdef NAME // NAME is undefined
368 // then lexPreprocessor() enters the lines-skipping mode.
369 // In this mode, it does not parse any tokens, because the code under
370 // the #ifdef may not even be a correct tablegen code. The preprocessor
371 // looks for lines containing other preprocessing directives, which
372 // may be prepended with whitespaces and C-style comments. If the line
373 // does not contain a preprocessing directive, it is skipped completely.
374 // Otherwise, the preprocessing directive is processed by recursively
375 // calling lexPreprocessor(). The processing of the encountered
376 // preprocessing directives includes updating preprocessing control stack
377 // and adding new macros into DefinedMacros set.
378 //
379 // The second parameter controls whether lexPreprocessor() is called from
380 // LexToken() (true) or recursively from lexPreprocessor() (false).
381 //
382 // If ReturnNextLiveToken is true, the method returns the next
383 // LEX token following the current directive or following the end
384 // of the disabled preprocessing region corresponding to this directive.
385 // If ReturnNextLiveToken is false, the method returns the first parameter,
386 // unless there were errors encountered in the disabled preprocessing
387 // region - in this case, it returns tgtok::Error.
388 tgtok::TokKind lexPreprocessor(tgtok::TokKind Kind,
389 bool ReturnNextLiveToken = true);
390
391 // Worker method for lexPreprocessor() to skip lines after some
392 // preprocessing directive up to the buffer end or to the directive
393 // that re-enables token processing. The method returns true
394 // upon processing the next directive that re-enables tokens
395 // processing. False is returned if an error was encountered.
396 //
397 // Note that prepSkipRegion() calls lexPreprocessor() to process
398 // encountered preprocessing directives. In this case, the second
399 // parameter to lexPreprocessor() is set to false. Being passed
400 // false ReturnNextLiveToken, lexPreprocessor() must never call
401 // prepSkipRegion(). We assert this by passing ReturnNextLiveToken
402 // to prepSkipRegion() and checking that it is never set to false.
403 bool prepSkipRegion(bool MustNeverBeFalse);
404
405 // Lex name of the macro after either #ifdef or #define. We could have used
406 // LexIdentifier(), but it has special handling of "include" word, which
407 // could result in awkward diagnostic errors. Consider:
408 // ----
409 // #ifdef include
410 // class ...
411 // ----
412 // LexIdentifier() will engage LexInclude(), which will complain about
413 // missing file with name "class". Instead, prepLexMacroName() will treat
414 // "include" as a normal macro name.
415 //
416 // On entry, CurPtr points to the end of a preprocessing directive word.
417 // The method allows for whitespaces between the preprocessing directive
418 // and the macro name. The allowed whitespaces are ' ' and '\t'.
419 //
420 // If the first non-whitespace symbol after the preprocessing directive
421 // is a valid start symbol for an identifier (i.e. [a-zA-Z_]), then
422 // the method updates TokStart to the position of the first non-whitespace
423 // symbol, sets CurPtr to the position of the macro name's last symbol,
424 // and returns a string reference to the macro name. Otherwise,
425 // TokStart is set to the first non-whitespace symbol after the preprocessing
426 // directive, and the method returns an empty string reference.
427 //
428 // In all cases, TokStart may be used to point to the word following
429 // the preprocessing directive.
430 StringRef prepLexMacroName();
431
432 // Skip any whitespaces starting from CurPtr. The method is used
433 // only in the lines-skipping mode to find the first non-whitespace
434 // symbol after or at CurPtr. Allowed whitespaces are ' ', '\t', '\n'
435 // and '\r'. The method skips C-style comments as well, because
436 // it is used to find the beginning of the preprocessing directive.
437 // If we do not handle C-style comments the following code would
438 // result in incorrect detection of a preprocessing directive:
439 // /*
440 // #ifdef NAME
441 // */
442 // As long as we skip C-style comments, the following code is correctly
443 // recognized as a preprocessing directive:
444 // /* first line comment
445 // second line comment */ #ifdef NAME
446 //
447 // The method returns true upon reaching the first non-whitespace symbol
448 // or EOF, CurPtr is set to point to this symbol. The method returns false,
449 // if an error occurred during skipping of a C-style comment.
450 bool prepSkipLineBegin();
451
452 // Skip any whitespaces or comments after a preprocessing directive.
453 // The method returns true upon reaching either end of the line
454 // or end of the file. If there is a multiline C-style comment
455 // after the preprocessing directive, the method skips
456 // the comment, so the final CurPtr may point to one of the next lines.
457 // The method returns false, if an error occurred during skipping
458 // C- or C++-style comment, or a non-whitespace symbol appears
459 // after the preprocessing directive.
460 //
461 // The method maybe called both during lines-skipping and tokens
462 // processing. It actually verifies that only whitespaces or/and
463 // comments follow a preprocessing directive.
464 //
465 // After the execution of this mehod, CurPtr points either to new line
466 // symbol, buffer end or non-whitespace symbol following the preprocesing
467 // directive.
468 bool prepSkipDirectiveEnd();
469
470 // Return true, if the current preprocessor control stack is such that
471 // we should allow lexer to process the next token, false - otherwise.
472 //
473 // In particular, the method returns true, if all the #ifdef/#else
474 // controls on the stack have their IsDefined member set to true.
475 bool prepIsProcessingEnabled();
476
477 // Report an error, if we reach EOF with non-empty preprocessing control
478 // stack. This means there is no matching #endif for the previous
479 // #ifdef/#else.
480 void prepReportPreprocessorStackError();
481};
482
483} // end namespace llvm
484
485#endif
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
StringSet - A set-like wrapper for the StringMap.
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: ArrayRef.h:41
Represents a location in source code.
Definition: SMLoc.h:23
Represents a range in source code.
Definition: SMLoc.h:48
This owns the files read by a parser, handles include stacks, and handles diagnostic wrangling.
Definition: SourceMgr.h:31
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
iterator begin() const
Definition: StringRef.h:111
StringSet - A wrapper for StringMap that provides set-like functionality.
Definition: StringSet.h:23
TGLexer - TableGen Lexer class.
Definition: TGLexer.h:189
SMRange getLocRange() const
Definition: TGLexer.cpp:66
tgtok::TokKind Lex()
Definition: TGLexer.h:215
int64_t getCurIntVal() const
Definition: TGLexer.h:230
std::pair< int64_t, unsigned > getCurBinaryIntVal() const
Definition: TGLexer.h:234
const std::string & getCurStrVal() const
Definition: TGLexer.h:225
tgtok::TokKind getCode() const
Definition: TGLexer.h:223
SMLoc getLoc() const
Definition: TGLexer.cpp:62
std::set< std::string > DependenciesSetTy
Definition: TGLexer.h:206
const DependenciesSetTy & getDependencies() const
Definition: TGLexer.h:219
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
static bool isBangOperator(tgtok::TokKind Kind)
isBangOperator - Return true if this is a bang operator.
Definition: TGLexer.h:173
@ r_square
Definition: TGLexer.h:41
@ XListSplat
Definition: TGLexer.h:125
@ XSetDagArg
Definition: TGLexer.h:158
@ BANG_OPERATOR_FIRST
Definition: TGLexer.h:110
@ XGetDagName
Definition: TGLexer.h:157
@ STRING_VALUE_FIRST
Definition: TGLexer.h:164
@ l_square
Definition: TGLexer.h:40
@ CodeFragment
Definition: TGLexer.h:168
@ XInterleave
Definition: TGLexer.h:127
@ MultiClass
Definition: TGLexer.h:106
@ BinaryIntVal
Definition: TGLexer.h:66
@ XSetDagName
Definition: TGLexer.h:159
@ BANG_OPERATOR_LAST
Definition: TGLexer.h:161
@ OBJECT_START_LAST
Definition: TGLexer.h:107
@ STRING_VALUE_LAST
Definition: TGLexer.h:169
@ XGetDagArg
Definition: TGLexer.h:156
@ XListConcat
Definition: TGLexer.h:124
@ OBJECT_START_FIRST
Definition: TGLexer.h:94
@ XStrConcat
Definition: TGLexer.h:126
@ FalseVal
Definition: TGLexer.h:59
@ dotdotdot
Definition: TGLexer.h:55
@ question
Definition: TGLexer.h:53
@ XListRemove
Definition: TGLexer.h:152
static bool isObjectStart(tgtok::TokKind Kind)
isObjectStart - Return true if this is a valid first token for a statement.
Definition: TGLexer.h:178
static bool isStringValue(tgtok::TokKind Kind)
isStringValue - Return true if this is a string value.
Definition: TGLexer.h:183
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
ArrayRef(const T &OneElt) -> ArrayRef< T >