1 //===- AsmLexer.cpp - Lexer for Assembly Files ----------------------------===//
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 class implements the lexer for assembly files.
12 //===----------------------------------------------------------------------===//
15 #include "llvm/Support/SourceMgr.h"
16 #include "llvm/Support/MemoryBuffer.h"
17 #include "llvm/Config/config.h" // for strtoull.
23 AsmLexer::AsmLexer(SourceMgr &SM) : SrcMgr(SM) {
25 CurBuf = SrcMgr.getMemoryBuffer(CurBuffer);
26 CurPtr = CurBuf->getBufferStart();
30 AsmLexer::~AsmLexer() {
33 SMLoc AsmLexer::getLoc() const {
34 return SMLoc::getFromPointer(TokStart);
37 void AsmLexer::PrintMessage(SMLoc Loc, const std::string &Msg,
38 const char *Type) const {
39 SrcMgr.PrintMessage(Loc, Msg, Type);
42 /// ReturnError - Set the error to the specified string at the specified
43 /// location. This is defined to always return AsmToken::Error.
44 AsmToken AsmLexer::ReturnError(const char *Loc, const std::string &Msg) {
45 SrcMgr.PrintMessage(SMLoc::getFromPointer(Loc), Msg, "error");
46 return AsmToken(AsmToken::Error, StringRef(Loc, 0));
49 /// EnterIncludeFile - Enter the specified file. This prints an error and
50 /// returns true on failure.
51 bool AsmLexer::EnterIncludeFile(const std::string &Filename) {
52 int NewBuf = SrcMgr.AddIncludeFile(Filename, SMLoc::getFromPointer(CurPtr));
56 // Save the line number and lex buffer of the includer.
58 CurBuf = SrcMgr.getMemoryBuffer(CurBuffer);
59 CurPtr = CurBuf->getBufferStart();
64 int AsmLexer::getNextChar() {
65 char CurChar = *CurPtr++;
68 return (unsigned char)CurChar;
70 // A nul character in the stream is either the end of the current buffer or
71 // a random nul in the file. Disambiguate that here.
72 if (CurPtr-1 != CurBuf->getBufferEnd())
73 return 0; // Just whitespace.
75 // If this is the end of an included file, pop the parent file off the
77 SMLoc ParentIncludeLoc = SrcMgr.getParentIncludeLoc(CurBuffer);
78 if (ParentIncludeLoc != SMLoc()) {
79 CurBuffer = SrcMgr.FindBufferContainingLoc(ParentIncludeLoc);
80 CurBuf = SrcMgr.getMemoryBuffer(CurBuffer);
81 CurPtr = ParentIncludeLoc.getPointer();
83 // Reset the token start pointer to the start of the new file.
89 // Otherwise, return end of file.
90 --CurPtr; // Another call to lex will return EOF again.
96 /// LexIdentifier: [a-zA-Z_.][a-zA-Z0-9_$.@]*
97 AsmToken AsmLexer::LexIdentifier() {
98 while (isalnum(*CurPtr) || *CurPtr == '_' || *CurPtr == '$' ||
99 *CurPtr == '.' || *CurPtr == '@')
101 return AsmToken(AsmToken::Identifier, StringRef(TokStart, CurPtr - TokStart));
104 /// LexPercent: Register: %[a-zA-Z0-9]+
105 AsmToken AsmLexer::LexPercent() {
106 if (!isalnum(*CurPtr))
107 return AsmToken(AsmToken::Percent, StringRef(CurPtr, 1)); // Single %.
109 while (isalnum(*CurPtr))
112 return AsmToken(AsmToken::Register, StringRef(TokStart, CurPtr - TokStart));
115 /// LexSlash: Slash: /
116 /// C-Style Comment: /* ... */
117 AsmToken AsmLexer::LexSlash() {
119 case '*': break; // C style comment.
120 case '/': return ++CurPtr, LexLineComment();
121 default: return AsmToken(AsmToken::Slash, StringRef(CurPtr, 1));
125 ++CurPtr; // skip the star.
127 int CurChar = getNextChar();
130 return ReturnError(TokStart, "unterminated comment");
132 // End of the comment?
133 if (CurPtr[0] != '/') break;
135 ++CurPtr; // End the */.
141 /// LexLineComment: Comment: #[^\n]*
143 AsmToken AsmLexer::LexLineComment() {
144 // FIXME: This is broken if we happen to a comment at the end of a file, which
145 // was .included, and which doesn't end with a newline.
146 int CurChar = getNextChar();
147 while (CurChar != '\n' && CurChar != '\n' && CurChar != EOF)
148 CurChar = getNextChar();
151 return AsmToken(AsmToken::Eof, StringRef(CurPtr, 0));
152 return AsmToken(AsmToken::EndOfStatement, StringRef(CurPtr, 0));
156 /// LexDigit: First character is [0-9].
157 /// Local Label: [0-9][:]
158 /// Forward/Backward Label: [0-9][fb]
159 /// Binary integer: 0b[01]+
160 /// Octal integer: 0[0-7]+
161 /// Hex integer: 0x[0-9a-fA-F]+
162 /// Decimal integer: [1-9][0-9]*
163 /// TODO: FP literal.
164 AsmToken AsmLexer::LexDigit() {
166 return ReturnError(TokStart, "FIXME: local label not implemented");
167 if (*CurPtr == 'f' || *CurPtr == 'b')
168 return ReturnError(TokStart, "FIXME: directional label not implemented");
170 // Decimal integer: [1-9][0-9]*
171 if (CurPtr[-1] != '0') {
172 while (isdigit(*CurPtr))
174 return AsmToken(AsmToken::Integer, StringRef(TokStart, CurPtr - TokStart),
175 strtoll(TokStart, 0, 10));
178 if (*CurPtr == 'b') {
180 const char *NumStart = CurPtr;
181 while (CurPtr[0] == '0' || CurPtr[0] == '1')
184 // Requires at least one binary digit.
185 if (CurPtr == NumStart)
186 return ReturnError(CurPtr-2, "Invalid binary number");
187 return AsmToken(AsmToken::Integer, StringRef(TokStart, CurPtr - TokStart),
188 strtoll(NumStart, 0, 2));
191 if (*CurPtr == 'x') {
193 const char *NumStart = CurPtr;
194 while (isxdigit(CurPtr[0]))
197 // Requires at least one hex digit.
198 if (CurPtr == NumStart)
199 return ReturnError(CurPtr-2, "Invalid hexadecimal number");
203 return ReturnError(CurPtr-2, "Invalid hexadecimal number");
204 if (errno == ERANGE) {
207 return ReturnError(CurPtr-2, "Invalid hexadecimal number");
209 return ReturnError(CurPtr-2, "Hexadecimal number out of range");
211 return AsmToken(AsmToken::Integer, StringRef(TokStart, CurPtr - TokStart),
212 (int64_t) strtoull(NumStart, 0, 16));
215 // Must be an octal number, it starts with 0.
216 while (*CurPtr >= '0' && *CurPtr <= '7')
218 return AsmToken(AsmToken::Integer, StringRef(TokStart, CurPtr - TokStart),
219 strtoll(TokStart, 0, 8));
222 /// LexQuote: String: "..."
223 AsmToken AsmLexer::LexQuote() {
224 int CurChar = getNextChar();
225 // TODO: does gas allow multiline string constants?
226 while (CurChar != '"') {
227 if (CurChar == '\\') {
229 CurChar = getNextChar();
233 return ReturnError(TokStart, "unterminated string constant");
235 CurChar = getNextChar();
238 return AsmToken(AsmToken::String, StringRef(TokStart, CurPtr - TokStart));
241 StringRef AsmLexer::LexUntilEndOfStatement() {
244 while (*CurPtr != '#' && // Start of line comment.
245 *CurPtr != ';' && // End of statement marker.
248 (*CurPtr != 0 || CurPtr != CurBuf->getBufferEnd()))
250 return StringRef(TokStart, CurPtr-TokStart);
253 AsmToken AsmLexer::LexToken() {
255 // This always consumes at least one character.
256 int CurChar = getNextChar();
260 // Handle identifier: [a-zA-Z_.][a-zA-Z0-9_$.@]*
261 if (isalpha(CurChar) || CurChar == '_' || CurChar == '.')
262 return LexIdentifier();
264 // Unknown character, emit an error.
265 return ReturnError(TokStart, "invalid character in input");
266 case EOF: return AsmToken(AsmToken::Eof, StringRef(TokStart, 0));
270 // Ignore whitespace.
272 case '\n': // FALL THROUGH.
273 case '\r': // FALL THROUGH.
274 case ';': return AsmToken(AsmToken::EndOfStatement, StringRef(TokStart, 1));
275 case ':': return AsmToken(AsmToken::Colon, StringRef(TokStart, 1));
276 case '+': return AsmToken(AsmToken::Plus, StringRef(TokStart, 1));
277 case '-': return AsmToken(AsmToken::Minus, StringRef(TokStart, 1));
278 case '~': return AsmToken(AsmToken::Tilde, StringRef(TokStart, 1));
279 case '(': return AsmToken(AsmToken::LParen, StringRef(TokStart, 1));
280 case ')': return AsmToken(AsmToken::RParen, StringRef(TokStart, 1));
281 case '*': return AsmToken(AsmToken::Star, StringRef(TokStart, 1));
282 case ',': return AsmToken(AsmToken::Comma, StringRef(TokStart, 1));
283 case '$': return AsmToken(AsmToken::Dollar, StringRef(TokStart, 1));
286 return ++CurPtr, AsmToken(AsmToken::EqualEqual, StringRef(TokStart, 2));
287 return AsmToken(AsmToken::Equal, StringRef(TokStart, 1));
290 return ++CurPtr, AsmToken(AsmToken::PipePipe, StringRef(TokStart, 2));
291 return AsmToken(AsmToken::Pipe, StringRef(TokStart, 1));
292 case '^': return AsmToken(AsmToken::Caret, StringRef(TokStart, 1));
295 return ++CurPtr, AsmToken(AsmToken::AmpAmp, StringRef(TokStart, 2));
296 return AsmToken(AsmToken::Amp, StringRef(TokStart, 1));
299 return ++CurPtr, AsmToken(AsmToken::ExclaimEqual, StringRef(TokStart, 2));
300 return AsmToken(AsmToken::Exclaim, StringRef(TokStart, 1));
301 case '%': return LexPercent();
302 case '/': return LexSlash();
303 case '#': return LexLineComment();
304 case '"': return LexQuote();
305 case '0': case '1': case '2': case '3': case '4':
306 case '5': case '6': case '7': case '8': case '9':
310 case '<': return ++CurPtr, AsmToken(AsmToken::LessLess,
311 StringRef(TokStart, 2));
312 case '=': return ++CurPtr, AsmToken(AsmToken::LessEqual,
313 StringRef(TokStart, 2));
314 case '>': return ++CurPtr, AsmToken(AsmToken::LessGreater,
315 StringRef(TokStart, 2));
316 default: return AsmToken(AsmToken::Less, StringRef(TokStart, 1));
320 case '>': return ++CurPtr, AsmToken(AsmToken::GreaterGreater,
321 StringRef(TokStart, 2));
322 case '=': return ++CurPtr, AsmToken(AsmToken::GreaterEqual,
323 StringRef(TokStart, 2));
324 default: return AsmToken(AsmToken::Greater, StringRef(TokStart, 1));
327 // TODO: Quoted identifiers (objc methods etc)
328 // local labels: [0-9][:]
329 // Forward/backward labels: [0-9][fb]
330 // Integers, fp constants, character constants.