/* YACC grammar for Chill expressions, for GDB. Copyright 1992, 1993 Free Software Foundation, Inc. This file is part of GDB. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* Parse a Chill expression from text in a string, and return the result as a struct expression pointer. That structure contains arithmetic operations in reverse polish, with constants represented by operations that are followed by special data. See expression.h for the details of the format. What is important here is that it can be built up sequentially during the process of parsing; the lower levels of the tree always come first in the result. Note that malloc's and realloc's in this file are transformed to xmalloc and xrealloc respectively by the same sed command in the makefile that remaps any other malloc/realloc inserted by the parser generator. Doing this with #defines and trying to control the interaction with include files ( and for example) just became too messy, particularly when such includes can be inserted at random times by the parser generator. Also note that the language accepted by this parser is more liberal than the one accepted by an actual Chill compiler. For example, the language rule that a simple name string can not be one of the reserved simple name strings is not enforced (e.g "case" is not treated as a reserved name). Another example is that Chill is a strongly typed language, and certain expressions that violate the type constraints may still be evaluated if gdb can do so in a meaningful manner, while such expressions would be rejected by the compiler. The reason for this more liberal behavior is the philosophy that the debugger is intended to be a tool that is used by the programmer when things go wrong, and as such, it should provide as few artificial barriers to it's use as possible. If it can do something meaningful, even something that violates language contraints that are enforced by the compiler, it should do so without complaint. */ %{ #include "defs.h" #include #include "expression.h" #include "language.h" #include "value.h" #include "parser-defs.h" #include "ch-lang.h" /* Remap normal yacc parser interface names (yyparse, yylex, yyerror, etc), as well as gratuitiously global symbol names, so we can have multiple yacc generated parsers in gdb. Note that these are only the variables produced by yacc. If other parser generators (bison, byacc, etc) produce additional global names that conflict at link time, then those parser generators need to be fixed instead of adding those names to this list. */ #define yymaxdepth chill_maxdepth #define yyparse chill_parse #define yylex chill_lex #define yyerror chill_error #define yylval chill_lval #define yychar chill_char #define yydebug chill_debug #define yypact chill_pact #define yyr1 chill_r1 #define yyr2 chill_r2 #define yydef chill_def #define yychk chill_chk #define yypgo chill_pgo #define yyact chill_act #define yyexca chill_exca #define yyerrflag chill_errflag #define yynerrs chill_nerrs #define yyps chill_ps #define yypv chill_pv #define yys chill_s #define yy_yys chill_yys #define yystate chill_state #define yytmp chill_tmp #define yyv chill_v #define yy_yyv chill_yyv #define yyval chill_val #define yylloc chill_lloc #define yyreds chill_reds /* With YYDEBUG defined */ #define yytoks chill_toks /* With YYDEBUG defined */ #ifndef YYDEBUG #define YYDEBUG 0 /* Default to no yydebug support */ #endif int yyparse PARAMS ((void)); static int yylex PARAMS ((void)); void yyerror PARAMS ((char *)); %} /* Although the yacc "value" of an expression is not used, since the result is stored in the structure being created, other node types do have values. */ %union { LONGEST lval; unsigned LONGEST ulval; struct { LONGEST val; struct type *type; } typed_val; double dval; struct symbol *sym; struct type *tval; struct stoken sval; struct ttype tsym; struct symtoken ssym; int voidval; struct block *bval; enum exp_opcode opcode; struct internalvar *ivar; struct type **tvec; int *ivec; } %token FIXME_01 %token FIXME_02 %token FIXME_03 %token FIXME_04 %token FIXME_05 %token FIXME_06 %token FIXME_07 %token FIXME_08 %token FIXME_09 %token FIXME_10 %token FIXME_11 %token FIXME_12 %token FIXME_13 %token FIXME_14 %token FIXME_15 %token FIXME_16 %token FIXME_17 %token FIXME_18 %token FIXME_19 %token FIXME_20 %token FIXME_21 %token FIXME_22 %token FIXME_24 %token FIXME_25 %token FIXME_26 %token FIXME_27 %token FIXME_28 %token FIXME_29 %token FIXME_30 %token INTEGER_LITERAL %token BOOLEAN_LITERAL %token CHARACTER_LITERAL %token FLOAT_LITERAL %token GENERAL_PROCEDURE_NAME %token LOCATION_NAME %token SET_LITERAL %token EMPTINESS_LITERAL %token CHARACTER_STRING_LITERAL %token BIT_STRING_LITERAL %token TYPENAME %token FIELD_NAME %token '.' %token ';' %token ':' %token CASE %token OF %token ESAC %token LOGIOR %token ORIF %token LOGXOR %token LOGAND %token ANDIF %token '=' %token NOTEQUAL %token '>' %token GTR %token '<' %token LEQ %token IN %token '+' %token '-' %token '*' %token '/' %token SLASH_SLASH %token MOD %token REM %token NOT %token POINTER %token RECEIVE %token '[' %token ']' %token '(' %token ')' %token UP %token IF %token THEN %token ELSE %token FI %token ELSIF %token ILLEGAL_TOKEN %token NUM %token PRED %token SUCC %token ABS %token CARD %token MAX_TOKEN %token MIN_TOKEN %token SIZE %token UPPER %token LOWER %token LENGTH /* Tokens which are not Chill tokens used in expressions, but rather GDB specific things that we recognize in the same context as Chill tokens (register names for example). */ %token GDB_REGNAME /* Machine register name */ %token GDB_LAST /* Value history */ %token GDB_VARIABLE /* Convenience variable */ %token GDB_ASSIGNMENT /* Assign value to somewhere */ %type location %type access_name %type primitive_value %type location_contents %type value_name %type literal %type tuple %type value_string_element %type value_string_slice %type value_array_element %type value_array_slice %type value_structure_field %type expression_conversion %type value_procedure_call %type value_built_in_routine_call %type chill_value_built_in_routine_call %type start_expression %type zero_adic_operator %type parenthesised_expression %type value %type undefined_value %type expression %type conditional_expression %type then_alternative %type else_alternative %type sub_expression %type value_case_alternative %type operand_0 %type operand_1 %type operand_2 %type operand_3 %type operand_4 %type operand_5 %type operand_6 %type synonym_name %type value_enumeration_name %type value_do_with_name %type value_receive_name %type string_primitive_value %type start_element %type left_element %type right_element %type slice_size %type array_primitive_value %type expression_list %type lower_element %type upper_element %type first_element %type mode_argument %type upper_lower_argument %type length_argument %type array_mode_name %type string_mode_name %type variant_structure_mode_name %type boolean_expression %type case_selector_list %type subexpression %type case_label_specification %type buffer_location %type single_assignment_action %type mode_name %% /* Z.200, 5.3.1 */ start : value { } | mode_name { write_exp_elt_opcode(OP_TYPE); write_exp_elt_type($1.type); write_exp_elt_opcode(OP_TYPE);} ; value : expression { $$ = 0; /* FIXME */ } | undefined_value { $$ = 0; /* FIXME */ } ; undefined_value : FIXME_01 { $$ = 0; /* FIXME */ } ; /* Z.200, 4.2.1 */ location : access_name | primitive_value POINTER { write_exp_elt_opcode (UNOP_IND); } ; /* Z.200, 4.2.2 */ access_name : LOCATION_NAME { write_exp_elt_opcode (OP_VAR_VALUE); write_exp_elt_sym ($1.sym); write_exp_elt_opcode (OP_VAR_VALUE); } | GDB_LAST /* gdb specific */ { write_exp_elt_opcode (OP_LAST); write_exp_elt_longcst ($1); write_exp_elt_opcode (OP_LAST); } | GDB_REGNAME /* gdb specific */ { write_exp_elt_opcode (OP_REGISTER); write_exp_elt_longcst ($1); write_exp_elt_opcode (OP_REGISTER); } | GDB_VARIABLE /* gdb specific */ { write_exp_elt_opcode (OP_INTERNALVAR); write_exp_elt_intern ($1); write_exp_elt_opcode (OP_INTERNALVAR); } | FIXME_03 { $$ = 0; /* FIXME */ } ; /* Z.200, 4.2.8 */ expression_list : expression { arglist_len = 1; } | expression_list ',' expression { arglist_len++; } /* Z.200, 5.2.1 */ primitive_value : location_contents { $$ = 0; /* FIXME */ } | value_name { $$ = 0; /* FIXME */ } | literal { $$ = 0; /* FIXME */ } | tuple { $$ = 0; /* FIXME */ } | value_string_element { $$ = 0; /* FIXME */ } | value_string_slice { $$ = 0; /* FIXME */ } | value_array_element { $$ = 0; /* FIXME */ } | value_array_slice { $$ = 0; /* FIXME */ } | value_structure_field { $$ = 0; /* FIXME */ } | expression_conversion { $$ = 0; /* FIXME */ } | value_procedure_call { $$ = 0; /* FIXME */ } | value_built_in_routine_call { $$ = 0; /* FIXME */ } | start_expression { $$ = 0; /* FIXME */ } | zero_adic_operator { $$ = 0; /* FIXME */ } | parenthesised_expression { $$ = 0; /* FIXME */ } ; /* Z.200, 5.2.2 */ location_contents: location { $$ = 0; /* FIXME */ } ; /* Z.200, 5.2.3 */ value_name : synonym_name { $$ = 0; /* FIXME */ } | value_enumeration_name { $$ = 0; /* FIXME */ } | value_do_with_name { $$ = 0; /* FIXME */ } | value_receive_name { $$ = 0; /* FIXME */ } | GENERAL_PROCEDURE_NAME { write_exp_elt_opcode (OP_VAR_VALUE); write_exp_elt_sym ($1.sym); write_exp_elt_opcode (OP_VAR_VALUE); } ; /* Z.200, 5.2.4.1 */ literal : INTEGER_LITERAL { write_exp_elt_opcode (OP_LONG); write_exp_elt_type ($1.type); write_exp_elt_longcst ((LONGEST) ($1.val)); write_exp_elt_opcode (OP_LONG); } | BOOLEAN_LITERAL { write_exp_elt_opcode (OP_BOOL); write_exp_elt_longcst ((LONGEST) $1); write_exp_elt_opcode (OP_BOOL); } | CHARACTER_LITERAL { write_exp_elt_opcode (OP_LONG); write_exp_elt_type ($1.type); write_exp_elt_longcst ((LONGEST) ($1.val)); write_exp_elt_opcode (OP_LONG); } | FLOAT_LITERAL { write_exp_elt_opcode (OP_DOUBLE); write_exp_elt_type (builtin_type_double); write_exp_elt_dblcst ($1); write_exp_elt_opcode (OP_DOUBLE); } | SET_LITERAL { $$ = 0; /* FIXME */ } | EMPTINESS_LITERAL { $$ = 0; /* FIXME */ } | CHARACTER_STRING_LITERAL { write_exp_elt_opcode (OP_STRING); write_exp_string ($1); write_exp_elt_opcode (OP_STRING); } | BIT_STRING_LITERAL { write_exp_elt_opcode (OP_BITSTRING); write_exp_bitstring ($1); write_exp_elt_opcode (OP_BITSTRING); } ; /* Z.200, 5.2.5 */ tuple : FIXME_04 { $$ = 0; /* FIXME */ } ; /* Z.200, 5.2.6 */ value_string_element: string_primitive_value '(' start_element ')' { $$ = 0; /* FIXME */ } ; /* Z.200, 5.2.7 */ value_string_slice: string_primitive_value '(' left_element ':' right_element ')' { $$ = 0; /* FIXME */ } | string_primitive_value '(' start_element UP slice_size ')' { $$ = 0; /* FIXME */ } ; /* Z.200, 5.2.8 */ value_array_element: array_primitive_value '(' /* This is to save the value of arglist_len being accumulated for each dimension. */ { start_arglist (); } expression_list ')' { write_exp_elt_opcode (MULTI_SUBSCRIPT); write_exp_elt_longcst ((LONGEST) end_arglist ()); write_exp_elt_opcode (MULTI_SUBSCRIPT); } ; /* Z.200, 5.2.9 */ value_array_slice: array_primitive_value '(' lower_element ':' upper_element ')' { $$ = 0; /* FIXME */ } | array_primitive_value '(' first_element UP slice_size ')' { $$ = 0; /* FIXME */ } ; /* Z.200, 5.2.10 */ value_structure_field: primitive_value FIELD_NAME { write_exp_elt_opcode (STRUCTOP_STRUCT); write_exp_string ($2); write_exp_elt_opcode (STRUCTOP_STRUCT); } ; /* Z.200, 5.2.11 */ expression_conversion: mode_name parenthesised_expression { write_exp_elt_opcode (UNOP_CAST); write_exp_elt_type ($1.type); write_exp_elt_opcode (UNOP_CAST); } ; /* Z.200, 5.2.12 */ value_procedure_call: FIXME_05 { $$ = 0; /* FIXME */ } ; /* Z.200, 5.2.13 */ value_built_in_routine_call: chill_value_built_in_routine_call { $$ = 0; /* FIXME */ } ; /* Z.200, 5.2.14 */ start_expression: FIXME_06 { $$ = 0; /* FIXME */ } /* Not in GNU-Chill */ ; /* Z.200, 5.2.15 */ zero_adic_operator: FIXME_07 { $$ = 0; /* FIXME */ } ; /* Z.200, 5.2.16 */ parenthesised_expression: '(' expression ')' { $$ = 0; /* FIXME */ } ; /* Z.200, 5.3.2 */ expression : operand_0 { $$ = 0; /* FIXME */ } | single_assignment_action { $$ = 0; /* FIXME */ } | conditional_expression { $$ = 0; /* FIXME */ } ; conditional_expression : IF boolean_expression then_alternative else_alternative FI { $$ = 0; /* FIXME */ } | CASE case_selector_list OF value_case_alternative '[' ELSE sub_expression ']' ESAC { $$ = 0; /* FIXME */ } ; then_alternative: THEN subexpression { $$ = 0; /* FIXME */ } ; else_alternative: ELSE subexpression { $$ = 0; /* FIXME */ } | ELSIF boolean_expression then_alternative else_alternative { $$ = 0; /* FIXME */ } ; sub_expression : expression { $$ = 0; /* FIXME */ } ; value_case_alternative: case_label_specification ':' sub_expression ';' { $$ = 0; /* FIXME */ } ; /* Z.200, 5.3.3 */ operand_0 : operand_1 { $$ = 0; /* FIXME */ } | operand_0 LOGIOR operand_1 { write_exp_elt_opcode (BINOP_BITWISE_IOR); } | operand_0 ORIF operand_1 { $$ = 0; /* FIXME */ } | operand_0 LOGXOR operand_1 { write_exp_elt_opcode (BINOP_BITWISE_XOR); } ; /* Z.200, 5.3.4 */ operand_1 : operand_2 { $$ = 0; /* FIXME */ } | operand_1 LOGAND operand_2 { write_exp_elt_opcode (BINOP_BITWISE_AND); } | operand_1 ANDIF operand_2 { $$ = 0; /* FIXME */ } ; /* Z.200, 5.3.5 */ operand_2 : operand_3 { $$ = 0; /* FIXME */ } | operand_2 '=' operand_3 { write_exp_elt_opcode (BINOP_EQUAL); } | operand_2 NOTEQUAL operand_3 { write_exp_elt_opcode (BINOP_NOTEQUAL); } | operand_2 '>' operand_3 { write_exp_elt_opcode (BINOP_GTR); } | operand_2 GTR operand_3 { write_exp_elt_opcode (BINOP_GEQ); } | operand_2 '<' operand_3 { write_exp_elt_opcode (BINOP_LESS); } | operand_2 LEQ operand_3 { write_exp_elt_opcode (BINOP_LEQ); } | operand_2 IN operand_3 { $$ = 0; /* FIXME */ } ; /* Z.200, 5.3.6 */ operand_3 : operand_4 { $$ = 0; /* FIXME */ } | operand_3 '+' operand_4 { write_exp_elt_opcode (BINOP_ADD); } | operand_3 '-' operand_4 { write_exp_elt_opcode (BINOP_SUB); } | operand_3 SLASH_SLASH operand_4 { write_exp_elt_opcode (BINOP_CONCAT); } ; /* Z.200, 5.3.7 */ operand_4 : operand_5 { $$ = 0; /* FIXME */ } | operand_4 '*' operand_5 { write_exp_elt_opcode (BINOP_MUL); } | operand_4 '/' operand_5 { write_exp_elt_opcode (BINOP_DIV); } | operand_4 MOD operand_5 { write_exp_elt_opcode (BINOP_MOD); } | operand_4 REM operand_5 { write_exp_elt_opcode (BINOP_REM); } ; /* Z.200, 5.3.8 */ operand_5 : operand_6 { $$ = 0; /* FIXME */ } | '-' operand_6 { write_exp_elt_opcode (UNOP_NEG); } | NOT operand_6 { write_exp_elt_opcode (UNOP_LOGICAL_NOT); } | parenthesised_expression literal /* We require the string operand to be a literal, to avoid some nasty parsing ambiguities. */ { write_exp_elt_opcode (BINOP_CONCAT); } ; /* Z.200, 5.3.9 */ operand_6 : POINTER location { write_exp_elt_opcode (UNOP_ADDR); } | RECEIVE buffer_location { $$ = 0; /* FIXME */ } | primitive_value { $$ = 0; /* FIXME */ } ; /* Z.200, 6.2 */ single_assignment_action : location GDB_ASSIGNMENT value { write_exp_elt_opcode (BINOP_ASSIGN); } ; /* Z.200, 6.20.3 */ chill_value_built_in_routine_call : NUM '(' expression ')' { $$ = 0; /* FIXME */ } | PRED '(' expression ')' { $$ = 0; /* FIXME */ } | SUCC '(' expression ')' { $$ = 0; /* FIXME */ } | ABS '(' expression ')' { $$ = 0; /* FIXME */ } | CARD '(' expression ')' { $$ = 0; /* FIXME */ } | MAX_TOKEN '(' expression ')' { $$ = 0; /* FIXME */ } | MIN_TOKEN '(' expression ')' { $$ = 0; /* FIXME */ } | SIZE '(' location ')' { $$ = 0; /* FIXME */ } | SIZE '(' mode_argument ')' { $$ = 0; /* FIXME */ } | UPPER '(' upper_lower_argument ')' { $$ = 0; /* FIXME */ } | LOWER '(' upper_lower_argument ')' { $$ = 0; /* FIXME */ } | LENGTH '(' length_argument ')' { $$ = 0; /* FIXME */ } ; mode_argument : mode_name { $$ = 0; /* FIXME */ } | array_mode_name '(' expression ')' { $$ = 0; /* FIXME */ } | string_mode_name '(' expression ')' { $$ = 0; /* FIXME */ } | variant_structure_mode_name '(' expression_list ')' { $$ = 0; /* FIXME */ } ; mode_name : TYPENAME ; upper_lower_argument : expression { $$ = 0; /* FIXME */ } | mode_name { $$ = 0; /* FIXME */ } ; length_argument : expression { $$ = 0; /* FIXME */ } ; /* Z.200, 12.4.3 */ array_primitive_value : primitive_value { $$ = 0; } ; /* Things which still need productions... */ array_mode_name : FIXME_08 { $$ = 0; } string_mode_name : FIXME_09 { $$ = 0; } variant_structure_mode_name: FIXME_10 { $$ = 0; } synonym_name : FIXME_11 { $$ = 0; } value_enumeration_name : FIXME_12 { $$ = 0; } value_do_with_name : FIXME_13 { $$ = 0; } value_receive_name : FIXME_14 { $$ = 0; } string_primitive_value : FIXME_15 { $$ = 0; } start_element : FIXME_16 { $$ = 0; } left_element : FIXME_17 { $$ = 0; } right_element : FIXME_18 { $$ = 0; } slice_size : FIXME_19 { $$ = 0; } lower_element : FIXME_20 { $$ = 0; } upper_element : FIXME_21 { $$ = 0; } first_element : FIXME_22 { $$ = 0; } boolean_expression : FIXME_26 { $$ = 0; } case_selector_list : FIXME_27 { $$ = 0; } subexpression : FIXME_28 { $$ = 0; } case_label_specification: FIXME_29 { $$ = 0; } buffer_location : FIXME_30 { $$ = 0; } %% /* Implementation of a dynamically expandable buffer for processing input characters acquired through lexptr and building a value to return in yylval. */ static char *tempbuf; /* Current buffer contents */ static int tempbufsize; /* Size of allocated buffer */ static int tempbufindex; /* Current index into buffer */ #define GROWBY_MIN_SIZE 64 /* Minimum amount to grow buffer by */ #define CHECKBUF(size) \ do { \ if (tempbufindex + (size) >= tempbufsize) \ { \ growbuf_by_size (size); \ } \ } while (0); /* Grow the static temp buffer if necessary, including allocating the first one on demand. */ static void growbuf_by_size (count) int count; { int growby; growby = max (count, GROWBY_MIN_SIZE); tempbufsize += growby; if (tempbuf == NULL) { tempbuf = (char *) malloc (tempbufsize); } else { tempbuf = (char *) realloc (tempbuf, tempbufsize); } } /* Try to consume a simple name string token. If successful, returns a pointer to a nullbyte terminated copy of the name that can be used in symbol table lookups. If not successful, returns NULL. */ static char * match_simple_name_string () { char *tokptr = lexptr; if (isalpha (*tokptr)) { char *result; do { tokptr++; } while (isalnum (*tokptr) || (*tokptr == '_')); yylval.sval.ptr = lexptr; yylval.sval.length = tokptr - lexptr; lexptr = tokptr; result = copy_name (yylval.sval); for (tokptr = result; *tokptr; tokptr++) if (isupper (*tokptr)) *tokptr = tolower(*tokptr); return result; } return (NULL); } /* Start looking for a value composed of valid digits as set by the base in use. Note that '_' characters are valid anywhere, in any quantity, and are simply ignored. Since we must find at least one valid digit, or reject this token as an integer literal, we keep track of how many digits we have encountered. */ static int decode_integer_value (base, tokptrptr, ivalptr) int base; char **tokptrptr; int *ivalptr; { char *tokptr = *tokptrptr; int temp; int digits = 0; while (*tokptr != '\0') { temp = tolower (*tokptr); tokptr++; switch (temp) { case '_': continue; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': temp -= '0'; break; case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': temp -= 'a'; temp += 10; break; default: temp = base; break; } if (temp < base) { digits++; *ivalptr *= base; *ivalptr += temp; } else { /* Found something not in domain for current base. */ tokptr--; /* Unconsume what gave us indigestion. */ break; } } /* If we didn't find any digits, then we don't have a valid integer value, so reject the entire token. Otherwise, update the lexical scan pointer, and return non-zero for success. */ if (digits == 0) { return (0); } else { *tokptrptr = tokptr; return (1); } } static int decode_integer_literal (valptr, tokptrptr) int *valptr; char **tokptrptr; { char *tokptr = *tokptrptr; int base = 0; int ival = 0; int explicit_base = 0; /* Look for an explicit base specifier, which is optional. */ switch (*tokptr) { case 'd': case 'D': explicit_base++; base = 10; tokptr++; break; case 'b': case 'B': explicit_base++; base = 2; tokptr++; break; case 'h': case 'H': explicit_base++; base = 16; tokptr++; break; case 'o': case 'O': explicit_base++; base = 8; tokptr++; break; default: base = 10; break; } /* If we found an explicit base ensure that the character after the explicit base is a single quote. */ if (explicit_base && (*tokptr++ != '\'')) { return (0); } /* Attempt to decode whatever follows as an integer value in the indicated base, updating the token pointer in the process and computing the value into ival. Also, if we have an explicit base, then the next character must not be a single quote, or we have a bitstring literal, so reject the entire token in this case. Otherwise, update the lexical scan pointer, and return non-zero for success. */ if (!decode_integer_value (base, &tokptr, &ival)) { return (0); } else if (explicit_base && (*tokptr == '\'')) { return (0); } else { *valptr = ival; *tokptrptr = tokptr; return (1); } } /* If it wasn't for the fact that floating point values can contain '_' characters, we could just let strtod do all the hard work by letting it try to consume as much of the current token buffer as possible and find a legal conversion. Unfortunately we need to filter out the '_' characters before calling strtod, which we do by copying the other legal chars to a local buffer to be converted. However since we also need to keep track of where the last unconsumed character in the input buffer is, we have transfer only as many characters as may compose a legal floating point value. */ static int match_float_literal () { char *tokptr = lexptr; char *buf; char *copy; char ch; double dval; extern double strtod (); /* Make local buffer in which to build the string to convert. This is required because underscores are valid in chill floating point numbers but not in the string passed to strtod to convert. The string will be no longer than our input string. */ copy = buf = (char *) alloca (strlen (tokptr) + 1); /* Transfer all leading digits to the conversion buffer, discarding any underscores. */ while (isdigit (*tokptr) || *tokptr == '_') { if (*tokptr != '_') { *copy++ = *tokptr; } tokptr++; } /* Now accept either a '.', or one of [eEdD]. Dot is legal regardless of whether we found any leading digits, and we simply accept it and continue on to look for the fractional part and/or exponent. One of [eEdD] is legal only if we have seen digits, and means that there is no fractional part. If we find neither of these, then this is not a floating point number, so return failure. */ switch (*tokptr++) { case '.': /* Accept and then look for fractional part and/or exponent. */ *copy++ = '.'; break; case 'e': case 'E': case 'd': case 'D': if (copy == buf) { return (0); } *copy++ = 'e'; goto collect_exponent; break; default: return (0); break; } /* We found a '.', copy any fractional digits to the conversion buffer, up to the first nondigit, non-underscore character. */ while (isdigit (*tokptr) || *tokptr == '_') { if (*tokptr != '_') { *copy++ = *tokptr; } tokptr++; } /* Look for an exponent, which must start with one of [eEdD]. If none is found, jump directly to trying to convert what we have collected so far. */ switch (*tokptr) { case 'e': case 'E': case 'd': case 'D': *copy++ = 'e'; tokptr++; break; default: goto convert_float; break; } /* Accept an optional '-' or '+' following one of [eEdD]. */ collect_exponent: if (*tokptr == '+' || *tokptr == '-') { *copy++ = *tokptr++; } /* Now copy an exponent into the conversion buffer. Note that at the moment underscores are *not* allowed in exponents. */ while (isdigit (*tokptr)) { *copy++ = *tokptr++; } /* If we transfered any chars to the conversion buffer, try to interpret its contents as a floating point value. If any characters remain, then we must not have a valid floating point string. */ convert_float: *copy = '\0'; if (copy != buf) { dval = strtod (buf, ©); if (*copy == '\0') { yylval.dval = dval; lexptr = tokptr; return (FLOAT_LITERAL); } } return (0); } /* Recognize a string literal. A string literal is a nonzero sequence of characters enclosed in matching single or double quotes, except that a single character inside single quotes is a character literal, which we reject as a string literal. To embed the terminator character inside a string, it is simply doubled (I.E. "this""is""one""string") */ static int match_string_literal () { char *tokptr = lexptr; for (tempbufindex = 0, tokptr++; *tokptr != '\0'; tokptr++) { CHECKBUF (1); if (*tokptr == *lexptr) { if (*(tokptr + 1) == *lexptr) { tokptr++; } else { break; } } tempbuf[tempbufindex++] = *tokptr; } if (*tokptr == '\0' /* no terminator */ || tempbufindex == 0 /* no string */ || (tempbufindex == 1 && *tokptr == '\'')) /* char literal */ { return (0); } else { tempbuf[tempbufindex] = '\0'; yylval.sval.ptr = tempbuf; yylval.sval.length = tempbufindex; lexptr = ++tokptr; return (CHARACTER_STRING_LITERAL); } } /* Recognize a character literal. A character literal is single character or a control sequence, enclosed in single quotes. A control sequence is a comma separated list of one or more integer literals, enclosed in parenthesis and introduced with a circumflex character. EX: 'a' '^(7)' '^(7,8)' As a GNU chill extension, the syntax C'xx' is also recognized as a character literal, where xx is a hex value for the character. Note that more than a single character, enclosed in single quotes, is a string literal. Also note that the control sequence form is not in GNU Chill since it is ambiguous with the string literal form using single quotes. I.E. is '^(7)' a character literal or a string literal. In theory it it possible to tell by context, but GNU Chill doesn't accept the control sequence form, so neither do we (for now the code is disabled). Returns CHARACTER_LITERAL if a match is found. */ static int match_character_literal () { char *tokptr = lexptr; int ival = 0; if ((tolower (*tokptr) == 'c') && (*(tokptr + 1) == '\'')) { /* We have a GNU chill extension form, so skip the leading "C'", decode the hex value, and then ensure that we have a trailing single quote character. */ tokptr += 2; if (!decode_integer_value (16, &tokptr, &ival) || (*tokptr != '\'')) { return (0); } tokptr++; } else if (*tokptr == '\'') { tokptr++; /* Determine which form we have, either a control sequence or the single character form. */ if ((*tokptr == '^') && (*(tokptr + 1) == '(')) { #if 0 /* Disable, see note above. -fnf */ /* Match and decode a control sequence. Return zero if we don't find a valid integer literal, or if the next unconsumed character after the integer literal is not the trailing ')'. FIXME: We currently don't handle the multiple integer literal form. */ tokptr += 2; if (!decode_integer_literal (&ival, &tokptr) || (*tokptr++ != ')')) { return (0); } #else return (0); #endif } else { ival = *tokptr++; } /* The trailing quote has not yet been consumed. If we don't find it, then we have no match. */ if (*tokptr++ != '\'') { return (0); } } else { /* Not a character literal. */ return (0); } yylval.typed_val.val = ival; yylval.typed_val.type = builtin_type_chill_char; lexptr = tokptr; return (CHARACTER_LITERAL); } /* Recognize an integer literal, as specified in Z.200 sec 5.2.4.2. Note that according to 5.2.4.2, a single "_" is also a valid integer literal, however GNU-chill requires there to be at least one "digit" in any integer literal. */ static int match_integer_literal () { char *tokptr = lexptr; int ival; if (!decode_integer_literal (&ival, &tokptr)) { return (0); } else { yylval.typed_val.val = ival; yylval.typed_val.type = builtin_type_int; lexptr = tokptr; return (INTEGER_LITERAL); } } /* Recognize a bit-string literal, as specified in Z.200 sec 5.2.4.8 Note that according to 5.2.4.8, a single "_" is also a valid bit-string literal, however GNU-chill requires there to be at least one "digit" in any bit-string literal. */ static int match_bitstring_literal () { char *tokptr = lexptr; int mask; int bitoffset = 0; int bitcount = 0; int base; int digit; tempbufindex = 0; /* Look for the required explicit base specifier. */ switch (*tokptr++) { case 'b': case 'B': base = 2; break; case 'o': case 'O': base = 8; break; case 'h': case 'H': base = 16; break; default: return (0); break; } /* Ensure that the character after the explicit base is a single quote. */ if (*tokptr++ != '\'') { return (0); } while (*tokptr != '\0' && *tokptr != '\'') { digit = tolower (*tokptr); tokptr++; switch (digit) { case '_': continue; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': digit -= '0'; break; case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': digit -= 'a'; digit += 10; break; default: return (0); break; } if (digit >= base) { /* Found something not in domain for current base. */ return (0); } else { /* Extract bits from digit, starting with the msbit appropriate for the current base, and packing them into the bitstring byte, starting at the lsbit. */ for (mask = (base >> 1); mask > 0; mask >>= 1) { bitcount++; CHECKBUF (1); if (digit & mask) { tempbuf[tempbufindex] |= (1 << bitoffset); } bitoffset++; if (bitoffset == HOST_CHAR_BIT) { bitoffset = 0; tempbufindex++; } } } } /* Verify that we consumed everything up to the trailing single quote, and that we found some bits (IE not just underbars). */ if (*tokptr++ != '\'') { return (0); } else { yylval.sval.ptr = tempbuf; yylval.sval.length = bitcount; lexptr = tokptr; return (BIT_STRING_LITERAL); } } /* Recognize tokens that start with '$'. These include: $regname A native register name or a "standard register name". Return token GDB_REGNAME. $variable A convenience variable with a name chosen by the user. Return token GDB_VARIABLE. $digits Value history with index , starting from the first value which has index 1. Return GDB_LAST. $$digits Value history with index relative to the last value. I.E. $$0 is the last value, $$1 is the one previous to that, $$2 is the one previous to $$1, etc. Return token GDB_LAST. $ | $0 | $$0 The last value in the value history. Return token GDB_LAST. $$ An abbreviation for the second to the last value in the value history, I.E. $$1 Return token GDB_LAST. Note that we currently assume that register names and convenience variables follow the convention of starting with a letter or '_'. */ static int match_dollar_tokens () { char *tokptr; int regno; int namelength; int negate; int ival; /* We will always have a successful match, even if it is just for a single '$', the abbreviation for $$0. So advance lexptr. */ tokptr = ++lexptr; if (*tokptr == '_' || isalpha (*tokptr)) { /* Look for a match with a native register name, usually something like "r0" for example. */ for (regno = 0; regno < NUM_REGS; regno++) { namelength = strlen (reg_names[regno]); if (STREQN (tokptr, reg_names[regno], namelength) && !isalnum (tokptr[namelength])) { yylval.lval = regno; lexptr += namelength + 1; return (GDB_REGNAME); } } /* Look for a match with a standard register name, usually something like "pc", which gdb always recognizes as the program counter regardless of what the native register name is. */ for (regno = 0; regno < num_std_regs; regno++) { namelength = strlen (std_regs[regno].name); if (STREQN (tokptr, std_regs[regno].name, namelength) && !isalnum (tokptr[namelength])) { yylval.lval = std_regs[regno].regnum; lexptr += namelength; return (GDB_REGNAME); } } /* Attempt to match against a convenience variable. Note that this will always succeed, because if no variable of that name already exists, the lookup_internalvar will create one for us. Also note that both lexptr and tokptr currently point to the start of the input string we are trying to match, and that we have already tested the first character for non-numeric, so we don't have to treat it specially. */ while (*tokptr == '_' || isalnum (*tokptr)) { tokptr++; } yylval.sval.ptr = lexptr; yylval.sval.length = tokptr - lexptr; yylval.ivar = lookup_internalvar (copy_name (yylval.sval)); lexptr = tokptr; return (GDB_VARIABLE); } /* Since we didn't match against a register name or convenience variable, our only choice left is a history value. */ if (*tokptr == '$') { negate = 1; ival = 1; tokptr++; } else { negate = 0; ival = 0; } /* Attempt to decode more characters as an integer value giving the index in the history list. If successful, the value will overwrite ival (currently 0 or 1), and if not, ival will be left alone, which is good since it is currently correct for the '$' or '$$' case. */ decode_integer_literal (&ival, &tokptr); yylval.lval = negate ? -ival : ival; lexptr = tokptr; return (GDB_LAST); } struct token { char *operator; int token; }; static const struct token idtokentab[] = { { "length", LENGTH }, { "lower", LOWER }, { "upper", UPPER }, { "andif", ANDIF }, { "pred", PRED }, { "succ", SUCC }, { "card", CARD }, { "size", SIZE }, { "orif", ORIF }, { "num", NUM }, { "abs", ABS }, { "max", MAX_TOKEN }, { "min", MIN_TOKEN }, { "mod", MOD }, { "rem", REM }, { "not", NOT }, { "xor", LOGXOR }, { "and", LOGAND }, { "in", IN }, { "or", LOGIOR } }; static const struct token tokentab2[] = { { ":=", GDB_ASSIGNMENT }, { "//", SLASH_SLASH }, { "->", POINTER }, { "/=", NOTEQUAL }, { "<=", LEQ }, { ">=", GTR } }; /* Read one token, getting characters through lexptr. */ /* This is where we will check to make sure that the language and the operators used are compatible. */ static int yylex () { unsigned int i; int token; char *simplename; struct symbol *sym; /* Skip over any leading whitespace. */ while (isspace (*lexptr)) { lexptr++; } /* Look for special single character cases which can't be the first character of some other multicharacter token. */ switch (*lexptr) { case '\0': return (0); case ',': case '=': case ';': case '!': case '+': case '*': case '(': case ')': case '[': case ']': return (*lexptr++); } /* Look for characters which start a particular kind of multicharacter token, such as a character literal, register name, convenience variable name, string literal, etc. */ switch (*lexptr) { case '\'': case '\"': /* First try to match a string literal, which is any nonzero sequence of characters enclosed in matching single or double quotes, except that a single character inside single quotes is a character literal, so we have to catch that case also. */ token = match_string_literal (); if (token != 0) { return (token); } if (*lexptr == '\'') { token = match_character_literal (); if (token != 0) { return (token); } } break; case 'C': case 'c': token = match_character_literal (); if (token != 0) { return (token); } break; case '$': token = match_dollar_tokens (); if (token != 0) { return (token); } break; } /* See if it is a special token of length 2. */ for (i = 0; i < sizeof (tokentab2) / sizeof (tokentab2[0]); i++) { if (STREQN (lexptr, tokentab2[i].operator, 2)) { lexptr += 2; return (tokentab2[i].token); } } /* Look for single character cases which which could be the first character of some other multicharacter token, but aren't, or we would already have found it. */ switch (*lexptr) { case '-': case ':': case '/': case '<': case '>': return (*lexptr++); } /* Look for a float literal before looking for an integer literal, so we match as much of the input stream as possible. */ token = match_float_literal (); if (token != 0) { return (token); } token = match_bitstring_literal (); if (token != 0) { return (token); } token = match_integer_literal (); if (token != 0) { return (token); } /* Try to match a simple name string, and if a match is found, then further classify what sort of name it is and return an appropriate token. Note that attempting to match a simple name string consumes the token from lexptr, so we can't back out if we later find that we can't classify what sort of name it is. */ simplename = match_simple_name_string (); if (simplename != NULL) { /* See if it is a reserved identifier. */ for (i = 0; i < sizeof (idtokentab) / sizeof (idtokentab[0]); i++) { if (STREQ (simplename, idtokentab[i].operator)) { return (idtokentab[i].token); } } /* Look for other special tokens. */ if (STREQ (simplename, "true")) { yylval.ulval = 1; return (BOOLEAN_LITERAL); } if (STREQ (simplename, "false")) { yylval.ulval = 0; return (BOOLEAN_LITERAL); } sym = lookup_symbol (simplename, expression_context_block, VAR_NAMESPACE, (int *) NULL, (struct symtab **) NULL); if (sym != NULL) { yylval.ssym.stoken.ptr = NULL; yylval.ssym.stoken.length = 0; yylval.ssym.sym = sym; yylval.ssym.is_a_field_of_this = 0; /* FIXME, C++'ism */ switch (SYMBOL_CLASS (sym)) { case LOC_BLOCK: /* Found a procedure name. */ return (GENERAL_PROCEDURE_NAME); case LOC_STATIC: /* Found a global or local static variable. */ return (LOCATION_NAME); case LOC_REGISTER: case LOC_ARG: case LOC_REF_ARG: case LOC_REGPARM: case LOC_LOCAL: case LOC_LOCAL_ARG: if (innermost_block == NULL || contained_in (block_found, innermost_block)) { innermost_block = block_found; } return (LOCATION_NAME); break; case LOC_CONST: case LOC_LABEL: return (LOCATION_NAME); break; case LOC_TYPEDEF: yylval.tsym.type = SYMBOL_TYPE (sym); return TYPENAME; case LOC_UNDEF: case LOC_CONST_BYTES: case LOC_OPTIMIZED_OUT: error ("Symbol \"%s\" names no location.", simplename); break; } } else if (!have_full_symbols () && !have_partial_symbols ()) { error ("No symbol table is loaded. Use the \"file\" command."); } else { error ("No symbol \"%s\" in current context.", simplename); } } /* Catch single character tokens which are not part of some longer token. */ switch (*lexptr) { case '.': /* Not float for example. */ lexptr++; while (isspace (*lexptr)) lexptr++; simplename = match_simple_name_string (); if (!simplename) return '.'; return FIELD_NAME; } return (ILLEGAL_TOKEN); } void yyerror (msg) char *msg; /* unused */ { printf ("Parsing: %s\n", lexptr); if (yychar < 256) { error ("Invalid syntax in expression near character '%c'.", yychar); } else { error ("Invalid syntax in expression"); } }