cmFortranParser: Parse keywords as lexical tokens

Teach the lexer to match and return specific Fortran keywords as tokens.
Update the parser to use these instead of always using a WORD token and
then checking the text.  This avoids extra string comparisons and will
allow more grammar productions to be unambiguously added later for
additional Fortran statements.

Source/cmFortranLexer.h

@@ -337,7 +337,7 @@ extern int cmFortran_yylex (yyscan_t yyscanner);
 #undef YY_DECL
 #endif
 
-#line 176 "cmFortranLexer.in.l"
+#line 182 "cmFortranLexer.in.l"
 
 
 #line 344 "cmFortranLexer.h"

Source/cmFortranLexer.in.l

@@ -151,6 +151,12 @@ $[ \t]*endif    { return F90PPR_ENDIF; }
 
 =|=>                     { return ASSIGNMENT_OP; }
 
+[Ee][Nn][Dd] { return END; }
+[Ii][Nn][Cc][Ll][Uu][Dd][Ee] { return INCLUDE; }
+[Ii][Nn][Tt][Ee][Rr][Ff][Aa][Cc][Ee] { return INTERFACE; }
+[Mm][Oo][Dd][Uu][Ll][Ee] { return MODULE; }
+[Uu][Ss][Ee] { return USE; }
+
 [a-zA-Z_][a-zA-Z_0-9]* {
   yylvalp->string = strdup(yytext);
   return WORD;

Source/cmFortranParser.y

@@ -52,12 +52,6 @@ static void cmFortran_yyerror(yyscan_t yyscanner, const char* message)
   cmFortranParser_Error(parser, message);
 }
 
-static bool cmFortranParserIsKeyword(const char* word,
-                                            const char* keyword)
-{
-  return cmsysString_strcasecmp(word, keyword) == 0;
-}
-
 /* Disable some warnings in the generated code.  */
 #ifdef _MSC_VER
 # pragma warning (disable: 4102) /* Unused goto label.  */
@@ -95,6 +89,11 @@ static bool cmFortranParserIsKeyword(const char* word,
 %token <number> UNTERMINATED_STRING
 %token <string> STRING WORD
 %token <string> CPP_INCLUDE_ANGLE
+%token END
+%token INCLUDE
+%token INTERFACE
+%token MODULE
+%token USE
 
 /*-------------------------------------------------------------------------*/
 /* grammar */
@@ -103,55 +102,45 @@ static bool cmFortranParserIsKeyword(const char* word,
 code: /* empty */ | code stmt;
 
 stmt:
-  WORD EOSTMT {
-    if (cmFortranParserIsKeyword($1, "interface")) {
-      cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
-      cmFortranParser_SetInInterface(parser, true);
-      }
-    free($1);
+  INTERFACE EOSTMT {
+    cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
+    cmFortranParser_SetInInterface(parser, true);
   }
-| WORD WORD other EOSTMT {
-    if (cmFortranParserIsKeyword($1, "use")) {
-      cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
-      cmFortranParser_RuleUse(parser, $2);
-    } else if (cmFortranParserIsKeyword($1, "module")) {
-      cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
-      cmFortranParser_RuleModule(parser, $2);
-    } else if (cmFortranParserIsKeyword($1, "interface")) {
-      cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
-      cmFortranParser_SetInInterface(parser, true);
-    } else if (cmFortranParserIsKeyword($2, "interface") &&
-               cmFortranParserIsKeyword($1, "end")) {
-      cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
-      cmFortranParser_SetInInterface(parser, false);
-    }
-    free($1);
+| USE WORD other EOSTMT {
+    cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
+    cmFortranParser_RuleUse(parser, $2);
     free($2);
   }
-| WORD DCOLON WORD other EOSTMT {
-    if (cmFortranParserIsKeyword($1, "use")) {
-      cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
-      cmFortranParser_RuleUse(parser, $3);
-    }
-    free($1);
+| MODULE WORD other EOSTMT {
+    cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
+    cmFortranParser_RuleModule(parser, $2);
+    free($2);
+  }
+| INTERFACE WORD other EOSTMT {
+    cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
+    cmFortranParser_SetInInterface(parser, true);
+    free($2);
+  }
+| END INTERFACE other EOSTMT {
+    cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
+    cmFortranParser_SetInInterface(parser, false);
+  }
+| USE DCOLON WORD other EOSTMT {
+    cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
+    cmFortranParser_RuleUse(parser, $3);
     free($3);
   }
-| WORD COMMA WORD DCOLON WORD other EOSTMT {
-    if (cmFortranParserIsKeyword($1, "use") &&
-        cmFortranParserIsKeyword($3, "non_intrinsic") ) {
+| USE COMMA WORD DCOLON WORD other EOSTMT {
+    if (cmsysString_strcasecmp($3, "non_intrinsic") == 0) {
       cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
       cmFortranParser_RuleUse(parser, $5);
     }
-    free($1);
     free($3);
     free($5);
   }
-| WORD STRING other EOSTMT {
-    if (cmFortranParserIsKeyword($1, "include")) {
-      cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
-      cmFortranParser_RuleInclude(parser, $2);
-    }
-    free($1);
+| INCLUDE STRING other EOSTMT {
+    cmFortranParser* parser = cmFortran_yyget_extra(yyscanner);
+    cmFortranParser_RuleInclude(parser, $2);
     free($2);
   }
 | CPP_LINE_DIRECTIVE STRING other EOSTMT {
@@ -224,6 +213,11 @@ other: /* empty */ | other misc_code ;
 
 misc_code:
   WORD                { free ($1); }
+| END
+| INCLUDE
+| INTERFACE
+| MODULE
+| USE
 | STRING              { free ($1); }
 | GARBAGE
 | ASSIGNMENT_OP

Source/cmFortranParserTokens.h

@@ -73,7 +73,12 @@ extern int cmFortran_yydebug;
     UNTERMINATED_STRING = 283,
     STRING = 284,
     WORD = 285,
-    CPP_INCLUDE_ANGLE = 286
+    CPP_INCLUDE_ANGLE = 286,
+    END = 287,
+    INCLUDE = 288,
+    INTERFACE = 289,
+    MODULE = 290,
+    USE = 291
   };
 #endif
 /* Tokens.  */
@@ -106,17 +111,22 @@ extern int cmFortran_yydebug;
 #define STRING 284
 #define WORD 285
 #define CPP_INCLUDE_ANGLE 286
+#define END 287
+#define INCLUDE 288
+#define INTERFACE 289
+#define MODULE 290
+#define USE 291
 
 /* Value type.  */
 #if ! defined YYSTYPE && ! defined YYSTYPE_IS_DECLARED
 
 union YYSTYPE
 {
-#line 81 "cmFortranParser.y" /* yacc.c:1909  */
+#line 75 "cmFortranParser.y" /* yacc.c:1909  */
 
   char* string;
 
-#line 120 "cmFortranParserTokens.h" /* yacc.c:1909  */
+#line 130 "cmFortranParserTokens.h" /* yacc.c:1909  */
 };
 
 typedef union YYSTYPE YYSTYPE;