1 /* Parse expressions for GDB.
2 Copyright (C) 1986, 89, 90, 91, 94, 98, 1999 Free Software Foundation, Inc.
3 Modified from expread.y by the Department of Computer Science at the
4 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 2 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, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
22 /* Parse an expression from text in a string,
23 and return the result as a struct expression pointer.
24 That structure contains arithmetic operations in reverse polish,
25 with constants represented by operations that are followed by special data.
26 See expression.h for the details of the format.
27 What is important here is that it can be built up sequentially
28 during the process of parsing; the lower levels of the tree always
29 come first in the result. */
34 #include "gdb_string.h"
38 #include "expression.h"
42 #include "parser-defs.h"
44 #include "symfile.h" /* for overlay functions */
46 /* Global variables declared in parser-defs.h (and commented there). */
47 struct expression
*expout
;
50 struct block
*expression_context_block
;
51 struct block
*innermost_block
;
53 union type_stack_elt
*type_stack
;
54 int type_stack_depth
, type_stack_size
;
60 static int expressiondebug
= 0;
62 extern int hp_som_som_object_present
;
65 free_funcalls
PARAMS ((void));
68 prefixify_expression
PARAMS ((struct expression
*));
71 prefixify_subexp
PARAMS ((struct expression
*, struct expression
*, int, int));
73 void _initialize_parse
PARAMS ((void));
75 /* Data structure for saving values of arglist_len for function calls whose
76 arguments contain other function calls. */
84 static struct funcall
*funcall_chain
;
86 /* Assign machine-independent names to certain registers
87 (unless overridden by the REGISTER_NAMES table) */
89 unsigned num_std_regs
= 0;
90 struct std_regs
*std_regs
;
92 /* The generic method for targets to specify how their registers are
93 named. The mapping can be derived from three sources:
94 REGISTER_NAME; std_regs; or a target specific alias hook. */
97 target_map_name_to_register (str
, len
)
103 /* First try target specific aliases. We try these first because on some
104 systems standard names can be context dependent (eg. $pc on a
105 multiprocessor can be could be any of several PCs). */
106 #ifdef REGISTER_NAME_ALIAS_HOOK
107 i
= REGISTER_NAME_ALIAS_HOOK (str
, len
);
112 /* Search architectural register name space. */
113 for (i
= 0; i
< NUM_REGS
; i
++)
114 if (REGISTER_NAME (i
) && len
== strlen (REGISTER_NAME (i
))
115 && STREQN (str
, REGISTER_NAME (i
), len
))
120 /* Try standard aliases */
121 for (i
= 0; i
< num_std_regs
; i
++)
122 if (std_regs
[i
].name
&& len
== strlen (std_regs
[i
].name
)
123 && STREQN (str
, std_regs
[i
].name
, len
))
125 return std_regs
[i
].regnum
;
131 /* Begin counting arguments for a function call,
132 saving the data about any containing call. */
137 register struct funcall
*new;
139 new = (struct funcall
*) xmalloc (sizeof (struct funcall
));
140 new->next
= funcall_chain
;
141 new->arglist_len
= arglist_len
;
146 /* Return the number of arguments in a function call just terminated,
147 and restore the data for the containing function call. */
152 register int val
= arglist_len
;
153 register struct funcall
*call
= funcall_chain
;
154 funcall_chain
= call
->next
;
155 arglist_len
= call
->arglist_len
;
160 /* Free everything in the funcall chain.
161 Used when there is an error inside parsing. */
166 register struct funcall
*call
, *next
;
168 for (call
= funcall_chain
; call
; call
= next
)
175 /* This page contains the functions for adding data to the struct expression
176 being constructed. */
178 /* Add one element to the end of the expression. */
180 /* To avoid a bug in the Sun 4 compiler, we pass things that can fit into
181 a register through here */
184 write_exp_elt (expelt
)
185 union exp_element expelt
;
187 if (expout_ptr
>= expout_size
)
190 expout
= (struct expression
*)
191 xrealloc ((char *) expout
, sizeof (struct expression
)
192 + EXP_ELEM_TO_BYTES (expout_size
));
194 expout
->elts
[expout_ptr
++] = expelt
;
198 write_exp_elt_opcode (expelt
)
199 enum exp_opcode expelt
;
201 union exp_element tmp
;
209 write_exp_elt_sym (expelt
)
210 struct symbol
*expelt
;
212 union exp_element tmp
;
220 write_exp_elt_block (b
)
223 union exp_element tmp
;
229 write_exp_elt_longcst (expelt
)
232 union exp_element tmp
;
234 tmp
.longconst
= expelt
;
240 write_exp_elt_dblcst (expelt
)
243 union exp_element tmp
;
245 tmp
.doubleconst
= expelt
;
251 write_exp_elt_type (expelt
)
254 union exp_element tmp
;
262 write_exp_elt_intern (expelt
)
263 struct internalvar
*expelt
;
265 union exp_element tmp
;
267 tmp
.internalvar
= expelt
;
272 /* Add a string constant to the end of the expression.
274 String constants are stored by first writing an expression element
275 that contains the length of the string, then stuffing the string
276 constant itself into however many expression elements are needed
277 to hold it, and then writing another expression element that contains
278 the length of the string. I.E. an expression element at each end of
279 the string records the string length, so you can skip over the
280 expression elements containing the actual string bytes from either
281 end of the string. Note that this also allows gdb to handle
282 strings with embedded null bytes, as is required for some languages.
284 Don't be fooled by the fact that the string is null byte terminated,
285 this is strictly for the convenience of debugging gdb itself. Gdb
286 Gdb does not depend up the string being null terminated, since the
287 actual length is recorded in expression elements at each end of the
288 string. The null byte is taken into consideration when computing how
289 many expression elements are required to hold the string constant, of
294 write_exp_string (str
)
297 register int len
= str
.length
;
299 register char *strdata
;
301 /* Compute the number of expression elements required to hold the string
302 (including a null byte terminator), along with one expression element
303 at each end to record the actual string length (not including the
304 null byte terminator). */
306 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
+ 1);
308 /* Ensure that we have enough available expression elements to store
311 if ((expout_ptr
+ lenelt
) >= expout_size
)
313 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
314 expout
= (struct expression
*)
315 xrealloc ((char *) expout
, (sizeof (struct expression
)
316 + EXP_ELEM_TO_BYTES (expout_size
)));
319 /* Write the leading length expression element (which advances the current
320 expression element index), then write the string constant followed by a
321 terminating null byte, and then write the trailing length expression
324 write_exp_elt_longcst ((LONGEST
) len
);
325 strdata
= (char *) &expout
->elts
[expout_ptr
];
326 memcpy (strdata
, str
.ptr
, len
);
327 *(strdata
+ len
) = '\0';
328 expout_ptr
+= lenelt
- 2;
329 write_exp_elt_longcst ((LONGEST
) len
);
332 /* Add a bitstring constant to the end of the expression.
334 Bitstring constants are stored by first writing an expression element
335 that contains the length of the bitstring (in bits), then stuffing the
336 bitstring constant itself into however many expression elements are
337 needed to hold it, and then writing another expression element that
338 contains the length of the bitstring. I.E. an expression element at
339 each end of the bitstring records the bitstring length, so you can skip
340 over the expression elements containing the actual bitstring bytes from
341 either end of the bitstring. */
344 write_exp_bitstring (str
)
347 register int bits
= str
.length
; /* length in bits */
348 register int len
= (bits
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
350 register char *strdata
;
352 /* Compute the number of expression elements required to hold the bitstring,
353 along with one expression element at each end to record the actual
354 bitstring length in bits. */
356 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
);
358 /* Ensure that we have enough available expression elements to store
361 if ((expout_ptr
+ lenelt
) >= expout_size
)
363 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
364 expout
= (struct expression
*)
365 xrealloc ((char *) expout
, (sizeof (struct expression
)
366 + EXP_ELEM_TO_BYTES (expout_size
)));
369 /* Write the leading length expression element (which advances the current
370 expression element index), then write the bitstring constant, and then
371 write the trailing length expression element. */
373 write_exp_elt_longcst ((LONGEST
) bits
);
374 strdata
= (char *) &expout
->elts
[expout_ptr
];
375 memcpy (strdata
, str
.ptr
, len
);
376 expout_ptr
+= lenelt
- 2;
377 write_exp_elt_longcst ((LONGEST
) bits
);
380 /* Add the appropriate elements for a minimal symbol to the end of
381 the expression. The rationale behind passing in text_symbol_type and
382 data_symbol_type was so that Modula-2 could pass in WORD for
383 data_symbol_type. Perhaps it still is useful to have those types vary
384 based on the language, but they no longer have names like "int", so
385 the initial rationale is gone. */
387 static struct type
*msym_text_symbol_type
;
388 static struct type
*msym_data_symbol_type
;
389 static struct type
*msym_unknown_symbol_type
;
392 write_exp_msymbol (msymbol
, text_symbol_type
, data_symbol_type
)
393 struct minimal_symbol
*msymbol
;
394 struct type
*text_symbol_type
;
395 struct type
*data_symbol_type
;
399 write_exp_elt_opcode (OP_LONG
);
400 write_exp_elt_type (lookup_pointer_type (builtin_type_void
));
402 addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
403 if (overlay_debugging
)
404 addr
= symbol_overlayed_address (addr
, SYMBOL_BFD_SECTION (msymbol
));
405 write_exp_elt_longcst ((LONGEST
) addr
);
407 write_exp_elt_opcode (OP_LONG
);
409 write_exp_elt_opcode (UNOP_MEMVAL
);
410 switch (msymbol
-> type
)
414 case mst_solib_trampoline
:
415 write_exp_elt_type (msym_text_symbol_type
);
422 write_exp_elt_type (msym_data_symbol_type
);
426 write_exp_elt_type (msym_unknown_symbol_type
);
429 write_exp_elt_opcode (UNOP_MEMVAL
);
432 /* Recognize tokens that start with '$'. These include:
434 $regname A native register name or a "standard
437 $variable A convenience variable with a name chosen
440 $digits Value history with index <digits>, starting
441 from the first value which has index 1.
443 $$digits Value history with index <digits> relative
444 to the last value. I.E. $$0 is the last
445 value, $$1 is the one previous to that, $$2
446 is the one previous to $$1, etc.
448 $ | $0 | $$0 The last value in the value history.
450 $$ An abbreviation for the second to the last
451 value in the value history, I.E. $$1
456 write_dollar_variable (str
)
459 /* Handle the tokens $digits; also $ (short for $0) and $$ (short for $$1)
460 and $$digits (equivalent to $<-digits> if you could type that). */
462 struct symbol
* sym
= NULL
;
463 struct minimal_symbol
* msym
= NULL
;
467 /* Double dollar means negate the number and add -1 as well.
468 Thus $$ alone means -1. */
469 if (str
.length
>= 2 && str
.ptr
[1] == '$')
476 /* Just dollars (one or two) */
480 /* Is the rest of the token digits? */
481 for (; i
< str
.length
; i
++)
482 if (!(str
.ptr
[i
] >= '0' && str
.ptr
[i
] <= '9'))
486 i
= atoi (str
.ptr
+ 1 + negate
);
492 /* Handle tokens that refer to machine registers:
493 $ followed by a register name. */
494 i
= target_map_name_to_register( str
.ptr
+ 1, str
.length
- 1 );
496 goto handle_register
;
498 /* On HP-UX, certain system routines (millicode) have names beginning
499 with $ or $$, e.g. $$dyncall, which handles inter-space procedure
500 calls on PA-RISC. Check for those, first. */
502 sym
= lookup_symbol (copy_name (str
), (struct block
*) NULL
,
503 VAR_NAMESPACE
, (int *) NULL
, (struct symtab
**) NULL
);
506 write_exp_elt_opcode (OP_VAR_VALUE
);
507 write_exp_elt_block (block_found
); /* set by lookup_symbol */
508 write_exp_elt_sym (sym
);
509 write_exp_elt_opcode (OP_VAR_VALUE
);
512 msym
= lookup_minimal_symbol (copy_name (str
), NULL
, NULL
);
515 write_exp_msymbol (msym
,
516 lookup_function_type (builtin_type_int
),
521 /* Any other names starting in $ are debugger internal variables. */
523 write_exp_elt_opcode (OP_INTERNALVAR
);
524 write_exp_elt_intern (lookup_internalvar (copy_name (str
) + 1));
525 write_exp_elt_opcode (OP_INTERNALVAR
);
528 write_exp_elt_opcode (OP_LAST
);
529 write_exp_elt_longcst ((LONGEST
) i
);
530 write_exp_elt_opcode (OP_LAST
);
533 write_exp_elt_opcode (OP_REGISTER
);
534 write_exp_elt_longcst (i
);
535 write_exp_elt_opcode (OP_REGISTER
);
540 /* Parse a string that is possibly a namespace / nested class
541 specification, i.e., something of the form A::B::C::x. Input
542 (NAME) is the entire string; LEN is the current valid length; the
543 output is a string, TOKEN, which points to the largest recognized
544 prefix which is a series of namespaces or classes. CLASS_PREFIX is
545 another output, which records whether a nested class spec was
546 recognized (= 1) or a fully qualified variable name was found (=
547 0). ARGPTR is side-effected (if non-NULL) to point to beyond the
548 string recognized and consumed by this routine.
550 The return value is a pointer to the symbol for the base class or
551 variable if found, or NULL if not found. Callers must check this
552 first -- if NULL, the outputs may not be correct.
554 This function is used c-exp.y. This is used specifically to get
555 around HP aCC (and possibly other compilers), which insists on
556 generating names with embedded colons for namespace or nested class
559 (Argument LEN is currently unused. 1997-08-27)
561 Callers must free memory allocated for the output string TOKEN. */
563 static const char coloncolon
[2] = {':',':'};
566 parse_nested_classes_for_hpacc (name
, len
, token
, class_prefix
, argptr
)
573 /* Comment below comes from decode_line_1 which has very similar
574 code, which is called for "break" command parsing. */
576 /* We have what looks like a class or namespace
577 scope specification (A::B), possibly with many
578 levels of namespaces or classes (A::B::C::D).
580 Some versions of the HP ANSI C++ compiler (as also possibly
581 other compilers) generate class/function/member names with
582 embedded double-colons if they are inside namespaces. To
583 handle this, we loop a few times, considering larger and
584 larger prefixes of the string as though they were single
585 symbols. So, if the initially supplied string is
586 A::B::C::D::foo, we have to look up "A", then "A::B",
587 then "A::B::C", then "A::B::C::D", and finally
588 "A::B::C::D::foo" as single, monolithic symbols, because
589 A, B, C or D may be namespaces.
591 Note that namespaces can nest only inside other
592 namespaces, and not inside classes. So we need only
593 consider *prefixes* of the string; there is no need to look up
594 "B::C" separately as a symbol in the previous example. */
598 char * prefix
= NULL
;
600 struct symbol
* sym_class
= NULL
;
601 struct symbol
* sym_var
= NULL
;
604 int colons_found
= 0;
609 /* Check for HP-compiled executable -- in other cases
610 return NULL, and caller must default to standard GDB
613 if (!hp_som_som_object_present
)
614 return (struct symbol
*) NULL
;
618 /* Skip over whitespace and possible global "::" */
619 while (*p
&& (*p
== ' ' || *p
== '\t')) p
++;
620 if (p
[0] == ':' && p
[1] == ':')
622 while (*p
&& (*p
== ' ' || *p
== '\t')) p
++;
626 /* Get to the end of the next namespace or class spec. */
627 /* If we're looking at some non-token, fail immediately */
629 if (!(isalpha (*p
) || *p
== '$' || *p
== '_'))
630 return (struct symbol
*) NULL
;
632 while (*p
&& (isalnum (*p
) || *p
== '$' || *p
== '_')) p
++;
636 /* If we have the start of a template specification,
637 scan right ahead to its end */
638 q
= find_template_name_end (p
);
645 /* Skip over "::" and whitespace for next time around */
646 while (*p
&& (*p
== ' ' || *p
== '\t')) p
++;
647 if (p
[0] == ':' && p
[1] == ':')
649 while (*p
&& (*p
== ' ' || *p
== '\t')) p
++;
651 /* Done with tokens? */
652 if (!*p
|| !(isalpha (*p
) || *p
== '$' || *p
== '_'))
655 tmp
= (char *) alloca (prefix_len
+ end
- start
+ 3);
658 memcpy (tmp
, prefix
, prefix_len
);
659 memcpy (tmp
+ prefix_len
, coloncolon
, 2);
660 memcpy (tmp
+ prefix_len
+ 2, start
, end
- start
);
661 tmp
[prefix_len
+ 2 + end
- start
] = '\000';
665 memcpy (tmp
, start
, end
- start
);
666 tmp
[end
- start
] = '\000';
670 prefix_len
= strlen (prefix
);
672 /* See if the prefix we have now is something we know about */
676 /* More tokens to process, so this must be a class/namespace */
677 sym_class
= lookup_symbol (prefix
, 0, STRUCT_NAMESPACE
,
678 0, (struct symtab
**) NULL
);
682 /* No more tokens, so try as a variable first */
683 sym_var
= lookup_symbol (prefix
, 0, VAR_NAMESPACE
,
684 0, (struct symtab
**) NULL
);
685 /* If failed, try as class/namespace */
687 sym_class
= lookup_symbol (prefix
, 0, STRUCT_NAMESPACE
,
688 0, (struct symtab
**) NULL
);
693 (t
= check_typedef (SYMBOL_TYPE (sym_class
)),
694 (TYPE_CODE (t
) == TYPE_CODE_STRUCT
695 || TYPE_CODE (t
) == TYPE_CODE_UNION
))))
697 /* We found a valid token */
698 *token
= (char *) xmalloc (prefix_len
+ 1 );
699 memcpy (*token
, prefix
, prefix_len
);
700 (*token
)[prefix_len
] = '\000';
704 /* No variable or class/namespace found, no more tokens */
706 return (struct symbol
*) NULL
;
709 /* Out of loop, so we must have found a valid token */
716 *argptr
= done
? p
: end
;
718 return sym_var
? sym_var
: sym_class
; /* found */
722 find_template_name_end (p
)
726 int just_seen_right
= 0;
727 int just_seen_colon
= 0;
728 int just_seen_space
= 0;
730 if (!p
|| (*p
!= '<'))
737 case '\'': case '\"':
739 /* In future, may want to allow these?? */
742 depth
++; /* start nested template */
743 if (just_seen_colon
|| just_seen_right
|| just_seen_space
)
744 return 0; /* but not after : or :: or > or space */
747 if (just_seen_colon
|| just_seen_right
)
748 return 0; /* end a (nested?) template */
749 just_seen_right
= 1; /* but not after : or :: */
750 if (--depth
== 0) /* also disallow >>, insist on > > */
751 return ++p
; /* if outermost ended, return */
754 if (just_seen_space
|| (just_seen_colon
> 1))
755 return 0; /* nested class spec coming up */
756 just_seen_colon
++; /* we allow :: but not :::: */
761 if (!((*p
>= 'a' && *p
<= 'z') || /* allow token chars */
762 (*p
>= 'A' && *p
<= 'Z') ||
763 (*p
>= '0' && *p
<= '9') ||
764 (*p
== '_') || (*p
== ',') || /* commas for template args */
765 (*p
== '&') || (*p
== '*') || /* pointer and ref types */
766 (*p
== '(') || (*p
== ')') || /* function types */
767 (*p
== '[') || (*p
== ']') )) /* array types */
782 /* Return a null-terminated temporary copy of the name
783 of a string token. */
789 memcpy (namecopy
, token
.ptr
, token
.length
);
790 namecopy
[token
.length
] = 0;
794 /* Reverse an expression from suffix form (in which it is constructed)
795 to prefix form (in which we can conveniently print or execute it). */
798 prefixify_expression (expr
)
799 register struct expression
*expr
;
802 sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expr
->nelts
);
803 register struct expression
*temp
;
804 register int inpos
= expr
->nelts
, outpos
= 0;
806 temp
= (struct expression
*) alloca (len
);
808 /* Copy the original expression into temp. */
809 memcpy (temp
, expr
, len
);
811 prefixify_subexp (temp
, expr
, inpos
, outpos
);
814 /* Return the number of exp_elements in the subexpression of EXPR
815 whose last exp_element is at index ENDPOS - 1 in EXPR. */
818 length_of_subexp (expr
, endpos
)
819 register struct expression
*expr
;
822 register int oplen
= 1;
823 register int args
= 0;
827 error ("?error in length_of_subexp");
829 i
= (int) expr
->elts
[endpos
- 1].opcode
;
835 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
836 oplen
= 5 + BYTES_TO_EXP_ELEM (oplen
+ 1);
859 case OP_F77_UNDETERMINED_ARGLIST
:
861 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
889 case STRUCTOP_STRUCT
:
897 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
898 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
902 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
903 oplen
= (oplen
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
904 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
);
909 args
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
910 args
-= longest_to_int (expr
->elts
[endpos
- 3].longconst
);
916 case TERNOP_SLICE_COUNT
:
921 case MULTI_SUBSCRIPT
:
923 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
926 case BINOP_ASSIGN_MODIFY
:
937 args
= 1 + (i
< (int) BINOP_END
);
942 oplen
+= length_of_subexp (expr
, endpos
- oplen
);
949 /* Copy the subexpression ending just before index INEND in INEXPR
950 into OUTEXPR, starting at index OUTBEG.
951 In the process, convert it from suffix to prefix form. */
954 prefixify_subexp (inexpr
, outexpr
, inend
, outbeg
)
955 register struct expression
*inexpr
;
956 struct expression
*outexpr
;
960 register int oplen
= 1;
961 register int args
= 0;
964 enum exp_opcode opcode
;
966 /* Compute how long the last operation is (in OPLEN),
967 and also how many preceding subexpressions serve as
968 arguments for it (in ARGS). */
970 opcode
= inexpr
->elts
[inend
- 1].opcode
;
975 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
976 oplen
= 5 + BYTES_TO_EXP_ELEM (oplen
+ 1);
999 case OP_F77_UNDETERMINED_ARGLIST
:
1001 args
= 1 + longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1027 case STRUCTOP_STRUCT
:
1036 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1037 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
1041 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1042 oplen
= (oplen
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
1043 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
);
1048 args
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1049 args
-= longest_to_int (inexpr
->elts
[inend
- 3].longconst
);
1055 case TERNOP_SLICE_COUNT
:
1059 case BINOP_ASSIGN_MODIFY
:
1065 case MULTI_SUBSCRIPT
:
1067 args
= 1 + longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1076 args
= 1 + ((int) opcode
< (int) BINOP_END
);
1079 /* Copy the final operator itself, from the end of the input
1080 to the beginning of the output. */
1082 memcpy (&outexpr
->elts
[outbeg
], &inexpr
->elts
[inend
],
1083 EXP_ELEM_TO_BYTES (oplen
));
1086 /* Find the lengths of the arg subexpressions. */
1087 arglens
= (int *) alloca (args
* sizeof (int));
1088 for (i
= args
- 1; i
>= 0; i
--)
1090 oplen
= length_of_subexp (inexpr
, inend
);
1095 /* Now copy each subexpression, preserving the order of
1096 the subexpressions, but prefixifying each one.
1097 In this loop, inend starts at the beginning of
1098 the expression this level is working on
1099 and marches forward over the arguments.
1100 outbeg does similarly in the output. */
1101 for (i
= 0; i
< args
; i
++)
1105 prefixify_subexp (inexpr
, outexpr
, inend
, outbeg
);
1110 /* This page contains the two entry points to this file. */
1112 /* Read an expression from the string *STRINGPTR points to,
1113 parse it, and return a pointer to a struct expression that we malloc.
1114 Use block BLOCK as the lexical context for variable names;
1115 if BLOCK is zero, use the block of the selected stack frame.
1116 Meanwhile, advance *STRINGPTR to point after the expression,
1117 at the first nonwhite character that is not part of the expression
1118 (possibly a null character).
1120 If COMMA is nonzero, stop if a comma is reached. */
1123 parse_exp_1 (stringptr
, block
, comma
)
1125 struct block
*block
;
1128 struct cleanup
*old_chain
;
1130 lexptr
= *stringptr
;
1133 type_stack_depth
= 0;
1135 comma_terminates
= comma
;
1137 if (lexptr
== 0 || *lexptr
== 0)
1138 error_no_arg ("expression to compute");
1140 old_chain
= make_cleanup ((make_cleanup_func
) free_funcalls
, 0);
1143 expression_context_block
= block
? block
: get_selected_block ();
1145 namecopy
= (char *) alloca (strlen (lexptr
) + 1);
1148 expout
= (struct expression
*)
1149 xmalloc (sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expout_size
));
1150 expout
->language_defn
= current_language
;
1151 make_cleanup ((make_cleanup_func
) free_current_contents
, &expout
);
1153 if (current_language
->la_parser ())
1154 current_language
->la_error (NULL
);
1156 discard_cleanups (old_chain
);
1158 /* Record the actual number of expression elements, and then
1159 reallocate the expression memory so that we free up any
1162 expout
->nelts
= expout_ptr
;
1163 expout
= (struct expression
*)
1164 xrealloc ((char *) expout
,
1165 sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expout_ptr
));;
1167 /* Convert expression from postfix form as generated by yacc
1168 parser, to a prefix form. */
1170 if (expressiondebug
)
1171 dump_prefix_expression (expout
, gdb_stdout
,
1172 "before conversion to prefix form");
1174 prefixify_expression (expout
);
1176 if (expressiondebug
)
1177 dump_postfix_expression (expout
, gdb_stdout
,
1178 "after conversion to prefix form");
1180 *stringptr
= lexptr
;
1184 /* Parse STRING as an expression, and complain if this fails
1185 to use up all of the contents of STRING. */
1188 parse_expression (string
)
1191 register struct expression
*exp
;
1192 exp
= parse_exp_1 (&string
, 0, 0);
1194 error ("Junk after end of expression.");
1198 /* Stuff for maintaining a stack of types. Currently just used by C, but
1199 probably useful for any language which declares its types "backwards". */
1203 enum type_pieces tp
;
1205 if (type_stack_depth
== type_stack_size
)
1207 type_stack_size
*= 2;
1208 type_stack
= (union type_stack_elt
*)
1209 xrealloc ((char *) type_stack
, type_stack_size
* sizeof (*type_stack
));
1211 type_stack
[type_stack_depth
++].piece
= tp
;
1218 if (type_stack_depth
== type_stack_size
)
1220 type_stack_size
*= 2;
1221 type_stack
= (union type_stack_elt
*)
1222 xrealloc ((char *) type_stack
, type_stack_size
* sizeof (*type_stack
));
1224 type_stack
[type_stack_depth
++].int_val
= n
;
1230 if (type_stack_depth
)
1231 return type_stack
[--type_stack_depth
].piece
;
1238 if (type_stack_depth
)
1239 return type_stack
[--type_stack_depth
].int_val
;
1240 /* "Can't happen". */
1244 /* Pop the type stack and return the type which corresponds to FOLLOW_TYPE
1245 as modified by all the stuff on the stack. */
1247 follow_types (follow_type
)
1248 struct type
*follow_type
;
1252 struct type
*range_type
;
1255 switch (pop_type ())
1261 follow_type
= lookup_pointer_type (follow_type
);
1264 follow_type
= lookup_reference_type (follow_type
);
1267 array_size
= pop_type_int ();
1268 /* FIXME-type-allocation: need a way to free this type when we are
1271 create_range_type ((struct type
*) NULL
,
1272 builtin_type_int
, 0,
1273 array_size
>= 0 ? array_size
- 1 : 0);
1275 create_array_type ((struct type
*) NULL
,
1276 follow_type
, range_type
);
1278 TYPE_ARRAY_UPPER_BOUND_TYPE(follow_type
)
1279 = BOUND_CANNOT_BE_DETERMINED
;
1282 /* FIXME-type-allocation: need a way to free this type when we are
1284 follow_type
= lookup_function_type (follow_type
);
1290 static void build_parse
PARAMS ((void));
1296 msym_text_symbol_type
=
1297 init_type (TYPE_CODE_FUNC
, 1, 0, "<text variable, no debug info>", NULL
);
1298 TYPE_TARGET_TYPE (msym_text_symbol_type
) = builtin_type_int
;
1299 msym_data_symbol_type
=
1300 init_type (TYPE_CODE_INT
, TARGET_INT_BIT
/ HOST_CHAR_BIT
, 0,
1301 "<data variable, no debug info>", NULL
);
1302 msym_unknown_symbol_type
=
1303 init_type (TYPE_CODE_INT
, 1, 0,
1304 "<variable (not text or data), no debug info>",
1307 /* create the std_regs table */
1326 /* create an empty table */
1327 std_regs
= xmalloc ((num_std_regs
+ 1) * sizeof *std_regs
);
1331 std_regs
[i
].name
= "pc";
1332 std_regs
[i
].regnum
= PC_REGNUM
;
1336 std_regs
[i
].name
= "fp";
1337 std_regs
[i
].regnum
= FP_REGNUM
;
1341 std_regs
[i
].name
= "sp";
1342 std_regs
[i
].regnum
= SP_REGNUM
;
1346 std_regs
[i
].name
= "ps";
1347 std_regs
[i
].regnum
= PS_REGNUM
;
1350 memset (&std_regs
[i
], 0, sizeof (std_regs
[i
]));
1354 _initialize_parse ()
1356 type_stack_size
= 80;
1357 type_stack_depth
= 0;
1358 type_stack
= (union type_stack_elt
*)
1359 xmalloc (type_stack_size
* sizeof (*type_stack
));
1364 add_set_cmd ("expressiondebug", class_maintenance
, var_zinteger
,
1365 (char *)&expressiondebug
,
1366 "Set expression debugging.\n\
1367 When non-zero, the internal representation of expressions will be printed.",