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"
31 #include "llvm/Support/Streams.h"
33 typedef std::pair<llvm::Record*, std::vector<llvm::Init*>*> SubClassRefTy;
34 #include "FileParser.h"
40 // Global variable recording the location of the include directory
41 std::vector<std::string> IncludeDirectories;
43 /// ParseInt - This has to handle the special case of binary numbers 0b0101
45 static int ParseInt(const char *Str) {
46 if (Str[0] == '0' && Str[1] == 'b')
47 return strtoll(Str+2, 0, 2);
48 return strtoll(Str, 0, 0);
51 static int CommentDepth = 0;
57 YY_BUFFER_STATE Buffer;
59 IncludeRec(const std::string &FN, FILE *F)
60 : Filename(FN), File(F), LineNo(0){
64 static std::vector<IncludeRec> IncludeStack;
67 if (IncludeStack.empty()) {
68 cerr << "At end of input: ";
69 return *cerr.stream();
72 for (unsigned i = 0, e = IncludeStack.size()-1; i != e; ++i)
73 cerr << "Included from " << IncludeStack[i].Filename << ":"
74 << IncludeStack[i].LineNo << ":\n";
75 cerr << "Parsing " << IncludeStack.back().Filename << ":"
76 << Filelineno << ": ";
77 return *cerr.stream();
80 /// ParseFile - this function begins the parsing of the specified tablegen file.
82 void ParseFile(const std::string &Filename,
83 const std::vector<std::string> &IncludeDirs) {
85 if (Filename != "-") {
86 F = fopen(Filename.c_str(), "r");
89 cerr << "Could not open input file '" + Filename + "'!\n";
92 IncludeStack.push_back(IncludeRec(Filename, F));
94 IncludeStack.push_back(IncludeRec("<stdin>", stdin));
97 // Record the location of the include directory so that the lexer can find
99 IncludeDirectories = IncludeDirs;
107 /// HandleInclude - This function is called when an include directive is
108 /// encountered in the input stream...
110 static void HandleInclude(const char *Buffer) {
111 unsigned Length = yyleng;
112 assert(Buffer[Length-1] == '"');
113 Buffer += strlen("include ");
114 Length -= strlen("include ");
115 while (*Buffer != '"') {
119 assert(Length >= 2 && "Double quotes not found?");
120 std::string Filename(Buffer+1, Buffer+Length-1);
121 //cerr << "Filename = '" << Filename << "'\n";
123 // Save the line number and lex buffer of the includer...
124 IncludeStack.back().LineNo = Filelineno;
125 IncludeStack.back().Buffer = YY_CURRENT_BUFFER;
127 // Open the new input file...
128 yyin = fopen(Filename.c_str(), "r");
130 // If we couldn't find the file in the current directory, look for it in
131 // the include directories.
133 std::string NextFilename;
134 for (unsigned i = 0, e = IncludeDirectories.size(); i != e; ++i) {
135 NextFilename = IncludeDirectories[i] + "/" + Filename;
136 if ((yyin = fopen(NextFilename.c_str(), "r")))
141 err() << "Could not find include file '" << Filename << "'!\n";
144 Filename = NextFilename;
147 // Add the file to our include stack...
148 IncludeStack.push_back(IncludeRec(Filename, yyin));
149 Filelineno = 1; // Reset line numbering...
150 //yyrestart(yyin); // Start lexing the new file...
152 yy_switch_to_buffer(yy_create_buffer(yyin, YY_BUF_SIZE));
155 /// yywrap - This is called when the lexer runs out of input in one of the
156 /// files. Switch back to an includer if an includee has run out of input.
160 if (IncludeStack.back().File != stdin)
161 fclose(IncludeStack.back().File);
162 IncludeStack.pop_back();
163 if (IncludeStack.empty()) return 1; // Top-level file is done.
165 // Otherwise, we need to switch back to a file which included the current one.
166 Filelineno = IncludeStack.back().LineNo; // Restore current line number
167 yy_switch_to_buffer(IncludeStack.back().Buffer);
171 } // End llvm namespace
173 using namespace llvm;
179 Identifier [a-zA-Z_][0-9a-zA-Z_]*
180 Integer [-+]?[0-9]+|0x[0-9a-fA-F]+|0b[01]+
181 CodeFragment \[\{([^}]+|\}[^\]])*\}\]
183 IncludeStr include[ \t\n]+\"[^"]*\"
187 {Comment} { /* Ignore comments */ }
189 {IncludeStr} { HandleInclude(yytext); }
190 {CodeFragment} { Filelval.StrVal = new std::string(yytext+2, yytext+yyleng-2);
191 return CODEFRAGMENT; }
195 bits { return BITS; }
196 string { return STRING; }
197 list { return LIST; }
198 code { return CODE; }
201 class { return CLASS; }
203 defm { return DEFM; }
204 multiclass { return MULTICLASS; }
205 field { return FIELD; }
209 !sra { return SRATOK; }
210 !srl { return SRLTOK; }
211 !shl { return SHLTOK; }
212 !strconcat { return STRCONCATTOK; }
215 {Identifier} { Filelval.StrVal = new std::string(yytext, yytext+yyleng);
217 ${Identifier} { Filelval.StrVal = new std::string(yytext+1, yytext+yyleng);
220 {StringVal} { Filelval.StrVal = new std::string(yytext+1, yytext+yyleng-1);
223 {Integer} { Filelval.IntVal = ParseInt(Filetext); return INTVAL; }
225 [ \t\n\r]+ { /* Ignore whitespace */ }
228 "/*" { BEGIN(comment); CommentDepth++; }
229 <comment>[^*/]* {} /* eat anything that's not a '*' or '/' */
230 <comment>"*"+[^*/]* {} /* eat up '*'s not followed by '/'s */
231 <comment>"/*" { ++CommentDepth; }
232 <comment>"/"+[^*/]* {} /* eat up /'s not followed by *'s */
233 <comment>"*"+"/" { if (!--CommentDepth) { BEGIN(INITIAL); } }
234 <comment><<EOF>> { err() << "Unterminated comment!\n"; exit(1); }
236 . { return Filetext[0]; }