1 /* YACC grammar for Modula-2 expressions, for GDB.
2 Copyright (C) 1986-2024 Free Software Foundation, Inc.
3 Generated from expread.y (now c-exp.y) and contributed by the Department
4 of Computer Science at the State University of New York at Buffalo, 1991.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 /* Parse a Modula-2 expression from text in a string,
22 and return the result as a struct expression pointer.
23 That structure contains arithmetic operations in reverse polish,
24 with constants represented by operations that are followed by special data.
25 See expression.h for the details of the format.
26 What is important here is that it can be built up sequentially
27 during the process of parsing; the lower levels of the tree always
28 come first in the result.
30 Note that malloc's and realloc's in this file are transformed to
31 xmalloc and xrealloc respectively by the same sed command in the
32 makefile that remaps any other malloc/realloc inserted by the parser
33 generator. Doing this with #defines and trying to control the interaction
34 with include files (<malloc.h> and <stdlib.h> for example) just became
35 too messy, particularly when such includes can be inserted at random
36 times by the parser generator. */
40 #include "expression.h"
43 #include "parser-defs.h"
48 #define parse_type(ps) builtin_type (ps->gdbarch ())
49 #define parse_m2_type(ps) builtin_m2_type (ps->gdbarch ())
51 /* Remap normal yacc parser interface names (yyparse, yylex, yyerror,
53 #define GDB_YY_REMAP_PREFIX m2_
56 /* The state of the parser, used internally when we are parsing the
59 static struct parser_state
*pstate
= NULL
;
63 static int yylex (void);
65 static void yyerror (const char *);
67 static int parse_number
(int);
69 /* The sign of the number being parsed. */
70 static int number_sign
= 1;
75 /* Although the yacc "value" of an expression is not used,
76 since the result is stored in the structure being created,
77 other node types do have values. */
88 const struct block
*bval
;
89 enum exp_opcode opcode
;
90 struct internalvar
*ivar
;
96 %type
<voidval
> exp type_exp start set
97 %type
<voidval
> variable
102 %token
<lval
> INT HEX ERROR
103 %token
<ulval
> UINT M2_TRUE M2_FALSE CHAR
106 /* Both NAME and TYPENAME tokens represent symbols in the input,
107 and both convey their data as strings.
108 But a TYPENAME is a string that happens to be defined as a typedef
109 or builtin type name (such as int or char)
110 and a NAME is any other symbol.
112 Contexts where this distinction is not important can use the
113 nonterminal "name", which matches either NAME or TYPENAME. */
116 %token
<sval
> NAME BLOCKNAME IDENT VARNAME
117 %token
<sval
> TYPENAME
119 %token SIZE CAP ORD HIGH ABS MIN_FUNC MAX_FUNC FLOAT_FUNC VAL CHR ODD TRUNC
121 %token INC DEC INCL EXCL
123 /* The GDB scope operator */
126 %token
<sval
> DOLLAR_VARIABLE
132 %left
'<' '>' LEQ GEQ
'=' NOTEQUAL
'#' IN
134 %left LOGICAL_AND
'&'
137 %left
'*' '/' DIV MOD
139 %right
'^' DOT
'[' '('
142 /* This is not an actual token ; it is used for precedence.
154 { pstate
->push_new
<type_operation
> ($1); }
159 exp
: exp
'^' %prec UNARY
160 { pstate
->wrap
<unop_ind_operation
> (); }
164 { number_sign
= -1; }
167 pstate
->wrap
<unary_neg_operation
> (); }
170 exp
: '+' exp %prec UNARY
171 { pstate
->wrap
<unary_plus_operation
> (); }
174 exp
: not_exp exp %prec UNARY
175 { pstate
->wrap
<unary_logical_not_operation
> (); }
182 exp
: CAP
'(' exp
')'
183 { error (_
("CAP function is not implemented")); }
186 exp
: ORD
'(' exp
')'
187 { error (_
("ORD function is not implemented")); }
190 exp
: ABS
'(' exp
')'
191 { error (_
("ABS function is not implemented")); }
194 exp
: HIGH
'(' exp
')'
195 { pstate
->wrap
<m2_unop_high_operation
> (); }
198 exp
: MIN_FUNC
'(' type
')'
199 { error (_
("MIN function is not implemented")); }
202 exp
: MAX_FUNC
'(' type
')'
203 { error (_
("MAX function is not implemented")); }
206 exp
: FLOAT_FUNC
'(' exp
')'
207 { error (_
("FLOAT function is not implemented")); }
210 exp
: VAL
'(' type
',' exp
')'
211 { error (_
("VAL function is not implemented")); }
214 exp
: CHR
'(' exp
')'
215 { error (_
("CHR function is not implemented")); }
218 exp
: ODD
'(' exp
')'
219 { error (_
("ODD function is not implemented")); }
222 exp
: TRUNC
'(' exp
')'
223 { error (_
("TRUNC function is not implemented")); }
226 exp
: TSIZE
'(' exp
')'
227 { pstate
->wrap
<unop_sizeof_operation
> (); }
230 exp
: SIZE exp %prec UNARY
231 { pstate
->wrap
<unop_sizeof_operation
> (); }
235 exp
: INC
'(' exp
')'
236 { pstate
->wrap
<preinc_operation
> (); }
239 exp
: INC
'(' exp
',' exp
')'
241 operation_up rhs
= pstate
->pop
();
242 operation_up lhs
= pstate
->pop
();
243 pstate
->push_new
<assign_modify_operation
>
244 (BINOP_ADD
, std
::move
(lhs
), std
::move
(rhs
));
248 exp
: DEC
'(' exp
')'
249 { pstate
->wrap
<predec_operation
> (); }
252 exp
: DEC
'(' exp
',' exp
')'
254 operation_up rhs
= pstate
->pop
();
255 operation_up lhs
= pstate
->pop
();
256 pstate
->push_new
<assign_modify_operation
>
257 (BINOP_SUB
, std
::move
(lhs
), std
::move
(rhs
));
263 pstate
->push_new
<structop_operation
>
264 (pstate
->pop
(), copy_name
($3));
272 { error (_
("Sets are not implemented."));}
275 exp
: INCL
'(' exp
',' exp
')'
276 { error (_
("Sets are not implemented."));}
279 exp
: EXCL
'(' exp
',' exp
')'
280 { error (_
("Sets are not implemented."));}
283 set
: '{' arglist
'}'
284 { error (_
("Sets are not implemented."));}
285 | type
'{' arglist
'}'
286 { error (_
("Sets are not implemented."));}
290 /* Modula-2 array subscript notation [a,b,c...]. */
292 /* This function just saves the number of arguments
293 that follow in the list. It is *not* specific to
295 { pstate
->start_arglist
(); }
296 non_empty_arglist
']' %prec DOT
298 gdb_assert
(pstate
->arglist_len
> 0);
299 std
::vector
<operation_up
> args
300 = pstate
->pop_vector
(pstate
->end_arglist
());
301 pstate
->push_new
<multi_subscript_operation
>
302 (pstate
->pop
(), std
::move
(args
));
307 /* This is to save the value of arglist_len
308 being accumulated by an outer function call. */
309 { pstate
->start_arglist
(); }
310 arglist
')' %prec DOT
312 std
::vector
<operation_up
> args
313 = pstate
->pop_vector
(pstate
->end_arglist
());
314 pstate
->push_new
<funcall_operation
>
315 (pstate
->pop
(), std
::move
(args
));
323 { pstate
->arglist_len
= 1; }
326 arglist
: arglist
',' exp %prec ABOVE_COMMA
327 { pstate
->arglist_len
++; }
332 { pstate
->arglist_len
= 1; }
336 : non_empty_arglist
',' exp %prec ABOVE_COMMA
337 { pstate
->arglist_len
++; }
341 exp
: '{' type
'}' exp %prec UNARY
343 pstate
->push_new
<unop_memval_operation
>
344 (pstate
->pop
(), $2);
348 exp
: type
'(' exp
')' %prec UNARY
350 pstate
->push_new
<unop_cast_operation
>
351 (pstate
->pop
(), $1);
359 /* Binary operators in order of decreasing precedence. Note that some
360 of these operators are overloaded! (ie. sets) */
364 { pstate
->wrap2
<repeat_operation
> (); }
368 { pstate
->wrap2
<mul_operation
> (); }
372 { pstate
->wrap2
<div_operation
> (); }
376 { pstate
->wrap2
<intdiv_operation
> (); }
380 { pstate
->wrap2
<rem_operation
> (); }
384 { pstate
->wrap2
<add_operation
> (); }
388 { pstate
->wrap2
<sub_operation
> (); }
392 { pstate
->wrap2
<equal_operation
> (); }
395 exp
: exp NOTEQUAL exp
396 { pstate
->wrap2
<notequal_operation
> (); }
398 { pstate
->wrap2
<notequal_operation
> (); }
402 { pstate
->wrap2
<leq_operation
> (); }
406 { pstate
->wrap2
<geq_operation
> (); }
410 { pstate
->wrap2
<less_operation
> (); }
414 { pstate
->wrap2
<gtr_operation
> (); }
417 exp
: exp LOGICAL_AND exp
418 { pstate
->wrap2
<logical_and_operation
> (); }
422 { pstate
->wrap2
<logical_or_operation
> (); }
426 { pstate
->wrap2
<assign_operation
> (); }
433 { pstate
->push_new
<bool_operation
> ($1); }
437 { pstate
->push_new
<bool_operation
> ($1); }
442 pstate
->push_new
<long_const_operation
>
443 (parse_m2_type
(pstate
)->builtin_int
, $1);
449 pstate
->push_new
<long_const_operation
>
450 (parse_m2_type
(pstate
)->builtin_card
, $1);
456 pstate
->push_new
<long_const_operation
>
457 (parse_m2_type
(pstate
)->builtin_char
, $1);
465 std
::copy
(std
::begin
($1), std
::end
($1),
467 pstate
->push_new
<float_const_operation
>
468 (parse_m2_type
(pstate
)->builtin_real
, data
);
475 exp
: SIZE
'(' type
')' %prec UNARY
477 pstate
->push_new
<long_const_operation
>
478 (parse_m2_type
(pstate
)->builtin_int
,
484 { error (_
("strings are not implemented")); }
487 /* This will be used for extensions later. Like adding modules. */
489 { $$
= $1->value_block
(); }
494 = lookup_symbol
(copy_name
($1).c_str
(),
495 pstate
->expression_context_block
,
496 SEARCH_VFT
, 0).symbol
;
501 /* GDB scope operator */
502 fblock
: block COLONCOLON BLOCKNAME
504 = lookup_symbol
(copy_name
($3).c_str
(), $1,
505 SEARCH_VFT
, 0).symbol
;
506 if
(!tem || tem
->aclass
() != LOC_BLOCK
)
507 error (_
("No function \"%s\" in specified context."),
508 copy_name
($3).c_str
());
513 /* Useful for assigning to PROCEDURE variables */
516 block_symbol sym
{ $1, nullptr
};
517 pstate
->push_new
<var_value_operation
> (sym
);
521 /* GDB internal ($foo) variable */
522 variable: DOLLAR_VARIABLE
523 { pstate
->push_dollar
($1); }
526 /* GDB scope operator */
527 variable: block COLONCOLON NAME
528 { struct block_symbol sym
529 = lookup_symbol
(copy_name
($3).c_str
(), $1,
533 error (_
("No symbol \"%s\" in specified context."),
534 copy_name
($3).c_str
());
535 if
(symbol_read_needs_frame
(sym.symbol
))
536 pstate
->block_tracker
->update
(sym
);
538 pstate
->push_new
<var_value_operation
> (sym
);
542 /* Base case for variables. */
544 { struct block_symbol sym
;
545 struct field_of_this_result is_a_field_of_this
;
547 std
::string name
= copy_name
($1);
549 = lookup_symbol
(name.c_str
(),
550 pstate
->expression_context_block
,
552 &is_a_field_of_this
);
554 pstate
->push_symbol
(name.c_str
(), sym
);
561 = lookup_typename
(pstate
->language
(),
562 copy_name
($1).c_str
(),
563 pstate
->expression_context_block
,
571 /* Take care of parsing a number (anything that starts with a digit).
572 Set yylval and return the token type; update lexptr.
573 LEN is the number of characters in it. */
575 /*** Needs some error checking for the float case ***/
578 parse_number
(int olen
)
580 const char *p
= pstate
->lexptr
;
584 int base
= input_radix
;
592 else if
(p
[len
-1] == 'C' || p
[len
-1] == 'B')
595 ischar
= p
[len
-1] == 'C';
599 /* Scan the number */
600 for
(c
= 0; c
< len
; c
++)
602 if
(p
[c
] == '.' && base
== 10)
604 /* It's a float since it contains a point. */
605 if
(!parse_float
(p
, len
,
606 parse_m2_type
(pstate
)->builtin_real
,
610 pstate
->lexptr
+= len
;
613 if
(p
[c
] == '.' && base
!= 10)
614 error (_
("Floating point numbers must be base 10."));
615 if
(base
== 10 && (p
[c
] < '0' || p
[c
] > '9'))
616 error (_
("Invalid digit \'%c\' in number."),p
[c
]);
623 if
( base
== 8 && (c
== '8' || c
== '9'))
624 error (_
("Invalid digit \'%c\' in octal number."),c
);
625 if
(c
>= '0' && c
<= '9')
629 if
(base
== 16 && c
>= 'A' && c
<= 'F')
637 if
(n
== 0 && prevn
== 0)
639 else if
(RANGE_CHECK
&& prevn
>= n
)
640 range_error
(_
("Overflow on numeric constant."));
646 if
(*p
== 'B' ||
*p
== 'C' ||
*p
== 'H')
647 pstate
->lexptr
++; /* Advance past B,C or H */
655 int int_bits
= gdbarch_int_bit
(pstate
->gdbarch
());
656 bool have_signed
= number_sign
== -1;
657 bool have_unsigned
= number_sign
== 1;
658 if
(have_signed
&& fits_in_type
(number_sign
, n
, int_bits
, true
))
663 else if
(have_unsigned
&& fits_in_type
(number_sign
, n
, int_bits
, false
))
669 error (_
("Overflow on numeric constant."));
681 { {'<', '>'}, NOTEQUAL
},
682 { {':', '='}, ASSIGN
},
685 { {':', ':'}, COLONCOLON
},
689 /* Some specific keywords */
696 static struct keyword keytab
[] =
699 {"IN", IN
},/* Note space after IN */
700 {"AND", LOGICAL_AND
},
718 {"FLOAT", FLOAT_FUNC
},
724 /* Depth of parentheses. */
725 static int paren_depth
;
727 /* Read one token, getting characters through lexptr. */
729 /* This is where we will check to make sure that the language and the
730 operators used are compatible */
738 const char *tokstart
;
743 pstate
->prev_lexptr
= pstate
->lexptr
;
745 tokstart
= pstate
->lexptr
;
748 /* See if it is a special token of length 2 */
749 for
( i
= 0 ; i
< (int) (sizeof tokentab2
/ sizeof tokentab2
[0]) ; i
++)
750 if
(strncmp
(tokentab2
[i
].name
, tokstart
, 2) == 0)
753 return tokentab2
[i
].token
;
756 switch
(c
= *tokstart
)
773 if
(paren_depth
== 0)
780 if
(pstate
->comma_terminates
&& paren_depth
== 0)
786 /* Might be a floating point number. */
787 if
(pstate
->lexptr
[1] >= '0' && pstate
->lexptr
[1] <= '9')
788 break
; /* Falls into number code. */
795 /* These are character tokens that appear as-is in the YACC grammar */
818 for
(namelen
= 1; (c
= tokstart
[namelen
]) != quote
&& c
!= '\0'; namelen
++)
821 c
= tokstart
[++namelen
];
822 if
(c
>= '0' && c
<= '9')
824 c
= tokstart
[++namelen
];
825 if
(c
>= '0' && c
<= '9')
826 c
= tokstart
[++namelen
];
830 error (_
("Unterminated string or character constant."));
831 yylval.sval.ptr
= tokstart
+ 1;
832 yylval.sval.length
= namelen
- 1;
833 pstate
->lexptr
+= namelen
+ 1;
835 if
(namelen
== 2) /* Single character */
837 yylval.ulval
= tokstart
[1];
844 /* Is it a number? */
845 /* Note: We have already dealt with the case of the token '.'.
846 See case '.' above. */
847 if
((c
>= '0' && c
<= '9'))
850 int got_dot
= 0, got_e
= 0;
851 const char *p
= tokstart
;
856 if
(!got_e
&& (*p
== 'e' ||
*p
== 'E'))
858 else if
(!got_dot
&& *p
== '.')
860 else if
(got_e
&& (p
[-1] == 'e' || p
[-1] == 'E')
861 && (*p
== '-' ||
*p
== '+'))
862 /* This is the sign of the exponent, not the end of the
865 else if
((*p
< '0' ||
*p
> '9') &&
866 (*p
< 'A' ||
*p
> 'F') &&
867 (*p
!= 'H')) /* Modula-2 hexadecimal number */
870 toktype
= parse_number
(p
- tokstart
);
871 if
(toktype
== ERROR
)
872 error (_
("Invalid number \"%.*s\"."), (int) (p
- tokstart
),
878 if
(!(c
== '_' || c
== '$'
879 ||
(c
>= 'a' && c
<= 'z') ||
(c
>= 'A' && c
<= 'Z')))
880 /* We must have come across a bad character (e.g. ';'). */
881 error (_
("Invalid character '%c' in expression."), c
);
883 /* It's a name. See how long it is. */
885 for
(c
= tokstart
[namelen
];
886 (c
== '_' || c
== '$' ||
(c
>= '0' && c
<= '9')
887 ||
(c
>= 'a' && c
<= 'z') ||
(c
>= 'A' && c
<= 'Z'));
888 c
= tokstart
[++namelen
])
891 /* The token "if" terminates the expression and is NOT
892 removed from the input stream. */
893 if
(namelen
== 2 && tokstart
[0] == 'i' && tokstart
[1] == 'f')
898 pstate
->lexptr
+= namelen
;
900 /* Lookup special keywords */
901 for
(i
= 0 ; i
< (int) (sizeof
(keytab
) / sizeof
(keytab
[0])) ; i
++)
902 if
(namelen
== strlen
(keytab
[i
].keyw
)
903 && strncmp
(tokstart
, keytab
[i
].keyw
, namelen
) == 0)
904 return keytab
[i
].token
;
906 yylval.sval.ptr
= tokstart
;
907 yylval.sval.length
= namelen
;
909 if
(*tokstart
== '$')
910 return DOLLAR_VARIABLE
;
912 /* Use token-type BLOCKNAME for symbols that happen to be defined as
913 functions. If this is not so, then ...
914 Use token-type TYPENAME for symbols that happen to be defined
915 currently as names of types; NAME for other symbols.
916 The caller is not constrained to care about the distinction. */
918 std
::string tmp
= copy_name
(yylval.sval
);
921 if
(lookup_symtab
(tmp.c_str
()))
923 sym
= lookup_symbol
(tmp.c_str
(), pstate
->expression_context_block
,
924 SEARCH_VFT
, 0).symbol
;
925 if
(sym
&& sym
->aclass
() == LOC_BLOCK
)
927 if
(lookup_typename
(pstate
->language
(),
928 tmp.c_str
(), pstate
->expression_context_block
, 1))
933 switch
(sym
->aclass
())
939 case LOC_REGPARM_ADDR
:
942 case LOC_CONST_BYTES
:
943 case LOC_OPTIMIZED_OUT
:
954 error (_
("internal: Undefined class in m2lex()"));
958 error (_
("internal: Unforseen case in m2lex()"));
961 error (_
("unhandled token in m2lex()"));
967 /* Built-in BOOLEAN type. This is sort of a hack. */
968 if
(startswith
(tokstart
, "TRUE"))
973 else if
(startswith
(tokstart
, "FALSE"))
980 /* Must be another type of name... */
986 m2_language::parser
(struct parser_state
*par_state
) const
988 /* Setting up the parser state. */
989 scoped_restore pstate_restore
= make_scoped_restore
(&pstate
);
990 gdb_assert
(par_state
!= NULL
);
994 int result
= yyparse ();
996 pstate
->set_operation
(pstate
->pop
());
1001 yyerror (const char *msg
)
1003 pstate
->parse_error
(msg
);