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"
30 #include "llvm/Config/config.h"
32 typedef std::pair<llvm::Record*, std::vector<llvm::Init*>*> SubClassRefTy;
33 #include "FileParser.h"
39 // Global variable recording the location of the include directory
40 std::vector<std::string> IncludeDirectories;
42 /// ParseInt - This has to handle the special case of binary numbers 0b0101
44 static int ParseInt(const char *Str) {
45 if (Str[0] == '0' && Str[1] == 'b')
46 return strtoll(Str+2, 0, 2);
47 return strtoll(Str, 0, 0);
50 static int CommentDepth = 0;
56 YY_BUFFER_STATE Buffer;
58 IncludeRec(const std::string &FN, FILE *F)
59 : Filename(FN), File(F), LineNo(0){
63 static std::vector<IncludeRec> IncludeStack;
66 if (IncludeStack.empty())
67 return std::cerr << "At end of input: ";
69 for (unsigned i = 0, e = IncludeStack.size()-1; i != e; ++i)
70 std::cerr << "Included from " << IncludeStack[i].Filename << ":"
71 << IncludeStack[i].LineNo << ":\n";
72 return std::cerr << "Parsing " << IncludeStack.back().Filename << ":"
73 << Filelineno << ": ";
76 /// ParseFile - this function begins the parsing of the specified tablegen file.
78 void ParseFile(const std::string &Filename,
79 const std::vector<std::string> &IncludeDirs) {
81 if (Filename != "-") {
82 F = fopen(Filename.c_str(), "r");
85 std::cerr << "Could not open input file '" + Filename + "'!\n";
88 IncludeStack.push_back(IncludeRec(Filename, F));
90 IncludeStack.push_back(IncludeRec("<stdin>", stdin));
93 // Record the location of the include directory so that the lexer can find
95 IncludeDirectories = IncludeDirs;
103 /// HandleInclude - This function is called when an include directive is
104 /// encountered in the input stream...
106 static void HandleInclude(const char *Buffer) {
107 unsigned Length = yyleng;
108 assert(Buffer[Length-1] == '"');
109 Buffer += strlen("include ");
110 Length -= strlen("include ");
111 while (*Buffer != '"') {
115 assert(Length >= 2 && "Double quotes not found?");
116 std::string Filename(Buffer+1, Buffer+Length-1);
117 //std::cerr << "Filename = '" << Filename << "'\n";
119 // Save the line number and lex buffer of the includer...
120 IncludeStack.back().LineNo = Filelineno;
121 IncludeStack.back().Buffer = YY_CURRENT_BUFFER;
123 // Open the new input file...
124 yyin = fopen(Filename.c_str(), "r");
126 // If we couldn't find the file in the current directory, look for it in
127 // the include directories.
129 std::string NextFilename;
130 for (unsigned i = 0, e = IncludeDirectories.size(); i != e; ++i) {
131 NextFilename = IncludeDirectories[i] + "/" + Filename;
132 if ((yyin = fopen(NextFilename.c_str(), "r")))
137 err() << "Could not find include file '" << Filename << "'!\n";
140 Filename = NextFilename;
143 // Add the file to our include stack...
144 IncludeStack.push_back(IncludeRec(Filename, yyin));
145 Filelineno = 1; // Reset line numbering...
146 //yyrestart(yyin); // Start lexing the new file...
148 yy_switch_to_buffer(yy_create_buffer(yyin, YY_BUF_SIZE));
151 /// yywrap - This is called when the lexer runs out of input in one of the
152 /// files. Switch back to an includer if an includee has run out of input.
156 if (IncludeStack.back().File != stdin)
157 fclose(IncludeStack.back().File);
158 IncludeStack.pop_back();
159 if (IncludeStack.empty()) return 1; // Top-level file is done.
161 // Otherwise, we need to switch back to a file which included the current one.
162 Filelineno = IncludeStack.back().LineNo; // Restore current line number
163 yy_switch_to_buffer(IncludeStack.back().Buffer);
167 } // End llvm namespace
169 using namespace llvm;
175 Identifier [a-zA-Z_][0-9a-zA-Z_]*
176 Integer [-+]?[0-9]+|0x[0-9a-fA-F]+|0b[01]+
177 CodeFragment \[\{([^}]+|\}[^\]])*\}\]
179 IncludeStr include[ \t\n]+\"[^"]*\"
183 {Comment} { /* Ignore comments */ }
185 {IncludeStr} { HandleInclude(yytext); }
186 {CodeFragment} { Filelval.StrVal = new std::string(yytext+2, yytext+yyleng-2);
187 return CODEFRAGMENT; }
191 bits { return BITS; }
192 string { return STRING; }
193 list { return LIST; }
194 code { return CODE; }
197 class { return CLASS; }
199 defm { return DEFM; }
200 multiclass { return MULTICLASS; }
201 field { return FIELD; }
205 !sra { return SRATOK; }
206 !srl { return SRLTOK; }
207 !shl { return SHLTOK; }
208 !strconcat { return STRCONCATTOK; }
211 {Identifier} { Filelval.StrVal = new std::string(yytext, yytext+yyleng);
213 ${Identifier} { Filelval.StrVal = new std::string(yytext+1, yytext+yyleng);
216 {StringVal} { Filelval.StrVal = new std::string(yytext+1, yytext+yyleng-1);
219 {Integer} { Filelval.IntVal = ParseInt(Filetext); return INTVAL; }
221 [ \t\n\r]+ { /* Ignore whitespace */ }
224 "/*" { BEGIN(comment); CommentDepth++; }
225 <comment>[^*/]* {} /* eat anything that's not a '*' or '/' */
226 <comment>"*"+[^*/]* {} /* eat up '*'s not followed by '/'s */
227 <comment>"/*" { ++CommentDepth; }
228 <comment>"/"+[^*/]* {} /* eat up /'s not followed by *'s */
229 <comment>"*"+"/" { if (!--CommentDepth) { BEGIN(INITIAL); } }
230 <comment><<EOF>> { err() << "Unterminated comment!\n"; exit(1); }
232 . { return Filetext[0]; }