initial checkin of SkSL compiler

src/sksl/sksl.flex

+/*
+
+        This file is IGNORED during the build process!
+
+        As this file is updated so infrequently and flex is not universally present on build machines,
+        the lex.sksl.c file must be manually regenerated if you make any changes to this file. Just run:
+
+                flex sksl.flex
+
+    You will have to manually add a copyright notice to the top of lex.sksl.c.
+    
+*/
+
+%option prefix="sksl"
+%option reentrant
+%option yylineno
+%option never-interactive
+%option nounistd
+
+DIGIT  [0-9]
+LETTER [a-zA-Z_$]
+
+%%
+
+{DIGIT}*"."{DIGIT}+([eE][+-]?{DIGIT}+)? { return SkSL::Token::FLOAT_LITERAL; }
+
+{DIGIT}+"."{DIGIT}*([eE][+-]?{DIGIT}+)? { return SkSL::Token::FLOAT_LITERAL; }
+
+{DIGIT}+([eE][+-]?{DIGIT}+) { return SkSL::Token::FLOAT_LITERAL; }
+
+{DIGIT}+ { return SkSL::Token::INT_LITERAL; }
+
+true { return SkSL::Token::TRUE_LITERAL; }
+
+false { return SkSL::Token::FALSE_LITERAL; }
+
+if { return SkSL::Token::IF; }
+
+else { return SkSL::Token::ELSE; }
+
+for { return SkSL::Token::FOR; }
+
+while { return SkSL::Token::WHILE; }
+
+do { return SkSL::Token::DO; }
+
+break { return SkSL::Token::BREAK; }
+
+continue { return SkSL::Token::CONTINUE; }
+
+discard { return SkSL::Token::DISCARD; }
+
+return { return SkSL::Token::RETURN; }
+
+in { return SkSL::Token::IN; }
+
+out { return SkSL::Token::OUT; }
+
+inout { return SkSL::Token::INOUT; }
+
+uniform { return SkSL::Token::UNIFORM; }
+
+const { return SkSL::Token::CONST; }
+
+lowp { return SkSL::Token::LOWP; }
+
+mediump { return SkSL::Token::MEDIUMP; }
+
+highp { return SkSL::Token::HIGHP; }
+
+struct { return SkSL::Token::STRUCT; }
+
+layout { return SkSL::Token::LAYOUT; }
+
+precision { return SkSL::Token::PRECISION; }
+
+{LETTER}({DIGIT}|{LETTER})* { return SkSL::Token::IDENTIFIER; }
+
+"#"{LETTER}({DIGIT}|{LETTER})* { return SkSL::Token::DIRECTIVE; }
+
+"(" { return SkSL::Token::LPAREN; }
+
+")" { return SkSL::Token::RPAREN; }
+
+"{" { return SkSL::Token::LBRACE; }
+
+"}" { return SkSL::Token::RBRACE; }
+
+"[" { return SkSL::Token::LBRACKET; }
+
+"]" { return SkSL::Token::RBRACKET; }
+
+"." { return SkSL::Token::DOT; }
+
+"," { return SkSL::Token::COMMA; }
+
+"++" { return SkSL::Token::PLUSPLUS; }
+
+"--" { return SkSL::Token::MINUSMINUS; }
+
+"+" { return SkSL::Token::PLUS; }
+
+"-" { return SkSL::Token::MINUS; }
+
+"*" { return SkSL::Token::STAR; }
+
+"/" { return SkSL::Token::SLASH; }
+
+"%" { return SkSL::Token::PERCENT; }
+
+"<<" { return SkSL::Token::SHL; }
+
+">>" { return SkSL::Token::SHR; }
+
+"|" { return SkSL::Token::BITWISEOR; }
+
+"^" { return SkSL::Token::BITWISEXOR; }
+
+"&" { return SkSL::Token::BITWISEAND; }
+
+"||" { return SkSL::Token::LOGICALOR; }

[dogben, 2016/06/20 16:23:19]

I don't know flex well enough to know if this will match when BITWISEOR is
listed before LOGICALOR.

[ethannicholas, 2016/06/20 17:45:49]

The order only matters when the matched text is the same length.

+
+"^^" { return SkSL::Token::LOGICALXOR; }
+
+"&&" { return SkSL::Token::LOGICALAND; }
+
+"!" { return SkSL::Token::NOT; }
+
+"?" { return SkSL::Token::QUESTION; }
+
+":" { return SkSL::Token::COLON; }
+
+"=" { return SkSL::Token::EQ; }
+
+"==" { return SkSL::Token::EQEQ; }
+
+"!=" { return SkSL::Token::NEQ; }
+
+">" { return SkSL::Token::GT; }
+
+"<" { return SkSL::Token::LT; }
+
+">=" { return SkSL::Token::GTEQ; }
+
+"<=" { return SkSL::Token::LTEQ; }
+
+"+=" { return SkSL::Token::PLUSEQ; }
+
+"-=" { return SkSL::Token::MINUSEQ; }
+
+"*=" { return SkSL::Token::STAREQ; }
+
+"/=" { return SkSL::Token::SLASHEQ; }
+
+"%=" { return SkSL::Token::PERCENTEQ; }
+
+"<<=" { return SkSL::Token::SHLEQ; }
+
+">>=" { return SkSL::Token::SHREQ; }
+
+"|=" { return SkSL::Token::BITWISEOREQ; }
+
+"^=" { return SkSL::Token::BITWISEXOREQ; }
+
+"&=" { return SkSL::Token::BITWISEANDEQ; }
+
+"||=" { return SkSL::Token::LOGICALOREQ; }
+
+"^^=" { return SkSL::Token::LOGICALXOREQ; }
+
+"&&=" { return SkSL::Token::LOGICALANDEQ; }
+
+";" { return SkSL::Token::SEMICOLON; }
+
+"//".* /* line comment */
+
+"/*"([^*]|"*"[^/])*"*/" /* block comment */
+
+[ \t\r\n]+  /* whitespace */
+
+.    { return SkSL::Token::INVALID_TOKEN; }
+
+%%
+
+int skslwrap(yyscan_t scanner) {
+    return 1; // terminate
+}