1 /*===-- FileLexer.l - Scanner for TableGen Files ----------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines a simple flex scanner for TableGen files. This is pretty
11 // straight-forward, except for the magic to handle file inclusion.
13 //===----------------------------------------------------------------------===*/
18 %option never-interactive
22 %option outfile="Lexer.cpp"
31 typedef std::pair<llvm::Record*, std::vector<llvm::Init*>*> SubClassRefTy;
32 #include "FileParser.h"
38 // Global variable recording the location of the include directory
39 std::vector<std::string> IncludeDirectories;
41 /// ParseInt - This has to handle the special case of binary numbers 0b0101
43 static int ParseInt(const char *Str) {
44 if (Str[0] == '0' && Str[1] == 'b')
45 return strtol(Str+2, 0, 2);
46 return strtol(Str, 0, 0);
49 static int CommentDepth = 0;
55 YY_BUFFER_STATE Buffer;
57 IncludeRec(const std::string &FN, FILE *F)
58 : Filename(FN), File(F), LineNo(0){
62 static std::vector<IncludeRec> IncludeStack;
65 if (IncludeStack.empty())
66 return std::cerr << "At end of input: ";
68 for (unsigned i = 0, e = IncludeStack.size()-1; i != e; ++i)
69 std::cerr << "Included from " << IncludeStack[i].Filename << ":"
70 << IncludeStack[i].LineNo << ":\n";
71 return std::cerr << "Parsing " << IncludeStack.back().Filename << ":"
72 << Filelineno << ": ";
75 /// ParseFile - this function begins the parsing of the specified tablegen file.
77 void ParseFile(const std::string &Filename,
78 const std::vector<std::string> &IncludeDirs) {
80 if (Filename != "-") {
81 F = fopen(Filename.c_str(), "r");
84 std::cerr << "Could not open input file '" + Filename + "'!\n";
87 IncludeStack.push_back(IncludeRec(Filename, F));
89 IncludeStack.push_back(IncludeRec("<stdin>", stdin));
92 // Record the location of the include directory so that the lexer can find
94 IncludeDirectories = IncludeDirs;
102 /// HandleInclude - This function is called when an include directive is
103 /// encountered in the input stream...
105 static void HandleInclude(const char *Buffer) {
106 unsigned Length = yyleng;
107 assert(Buffer[Length-1] == '"');
108 Buffer += strlen("include ");
109 Length -= strlen("include ");
110 while (*Buffer != '"') {
114 assert(Length >= 2 && "Double quotes not found?");
115 std::string Filename(Buffer+1, Buffer+Length-1);
116 //std::cerr << "Filename = '" << Filename << "'\n";
118 // Save the line number and lex buffer of the includer...
119 IncludeStack.back().LineNo = Filelineno;
120 IncludeStack.back().Buffer = YY_CURRENT_BUFFER;
122 // Open the new input file...
123 yyin = fopen(Filename.c_str(), "r");
125 // If we couldn't find the file in the current directory, look for it in
126 // the include directories.
128 std::string NextFilename;
129 for (unsigned i = 0, e = IncludeDirectories.size(); i != e; ++i) {
130 NextFilename = IncludeDirectories[i] + "/" + Filename;
131 if ((yyin = fopen(NextFilename.c_str(), "r")))
136 err() << "Could not find include file '" << Filename << "'!\n";
139 Filename = NextFilename;
142 // Add the file to our include stack...
143 IncludeStack.push_back(IncludeRec(Filename, yyin));
144 Filelineno = 1; // Reset line numbering...
145 //yyrestart(yyin); // Start lexing the new file...
147 yy_switch_to_buffer(yy_create_buffer(yyin, YY_BUF_SIZE));
150 /// yywrap - This is called when the lexer runs out of input in one of the
151 /// files. Switch back to an includer if an includee has run out of input.
155 if (IncludeStack.back().File != stdin)
156 fclose(IncludeStack.back().File);
157 IncludeStack.pop_back();
158 if (IncludeStack.empty()) return 1; // Top-level file is done.
160 // Otherwise, we need to switch back to a file which included the current one.
161 Filelineno = IncludeStack.back().LineNo; // Restore current line number
162 yy_switch_to_buffer(IncludeStack.back().Buffer);
166 } // End llvm namespace
168 using namespace llvm;
174 Identifier [a-zA-Z_][0-9a-zA-Z_]*
175 Integer [-+]?[0-9]+|0x[0-9a-fA-F]+|0b[01]+
176 CodeFragment \[\{([^}]+|\}[^\]])*\}\]
178 IncludeStr include[ \t\n]+\"[^"]*\"
182 {Comment} { /* Ignore comments */ }
184 {IncludeStr} { HandleInclude(yytext); }
185 {CodeFragment} { Filelval.StrVal = new std::string(yytext+2, yytext+yyleng-2);
186 return CODEFRAGMENT; }
190 bits { return BITS; }
191 string { return STRING; }
192 list { return LIST; }
193 code { return CODE; }
196 class { return CLASS; }
198 defm { return DEFM; }
199 multiclass { return MULTICLASS; }
200 field { return FIELD; }
204 !sra { return SRATOK; }
205 !srl { return SRLTOK; }
206 !shl { return SHLTOK; }
207 !strconcat { return STRCONCATTOK; }
210 {Identifier} { Filelval.StrVal = new std::string(yytext, yytext+yyleng);
212 ${Identifier} { Filelval.StrVal = new std::string(yytext+1, yytext+yyleng);
215 {StringVal} { Filelval.StrVal = new std::string(yytext+1, yytext+yyleng-1);
218 {Integer} { Filelval.IntVal = ParseInt(Filetext); return INTVAL; }
220 [ \t\n\r]+ { /* Ignore whitespace */ }
223 "/*" { BEGIN(comment); CommentDepth++; }
224 <comment>[^*/]* {} /* eat anything that's not a '*' or '/' */
225 <comment>"*"+[^*/]* {} /* eat up '*'s not followed by '/'s */
226 <comment>"/*" { ++CommentDepth; }
227 <comment>"/"+[^*/]* {} /* eat up /'s not followed by *'s */
228 <comment>"*"+"/" { if (!--CommentDepth) { BEGIN(INITIAL); } }
229 <comment><<EOF>> { err() << "Unterminated comment!\n"; exit(1); }
231 . { return Filetext[0]; }