1 /* Parse expressions for GDB.
2 Copyright 1986, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
4 Modified from expread.y by the Department of Computer Science at the
5 State University of New York at Buffalo, 1991.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 /* Parse an expression from text in a string,
25 and return the result as a struct expression pointer.
26 That structure contains arithmetic operations in reverse polish,
27 with constants represented by operations that are followed by special data.
28 See expression.h for the details of the format.
29 What is important here is that it can be built up sequentially
30 during the process of parsing; the lower levels of the tree always
31 come first in the result. */
36 #include "gdb_string.h"
40 #include "expression.h"
44 #include "parser-defs.h"
46 #include "symfile.h" /* for overlay functions */
47 #include "inferior.h" /* for NUM_PSEUDO_REGS. NOTE: replace
48 with "gdbarch.h" when appropriate. */
50 #include "builtin-regs.h"
51 #include "gdb_assert.h"
54 /* Symbols which architectures can redefine. */
56 /* Some systems have routines whose names start with `$'. Giving this
57 macro a non-zero value tells GDB's expression parser to check for
58 such routines when parsing tokens that begin with `$'.
60 On HP-UX, certain system routines (millicode) have names beginning
61 with `$' or `$$'. For example, `$$dyncall' is a millicode routine
62 that handles inter-space procedure calls on PA-RISC. */
63 #ifndef SYMBOLS_CAN_START_WITH_DOLLAR
64 #define SYMBOLS_CAN_START_WITH_DOLLAR (0)
69 /* Global variables declared in parser-defs.h (and commented there). */
70 struct expression
*expout
;
73 struct block
*expression_context_block
;
74 struct block
*innermost_block
;
76 union type_stack_elt
*type_stack
;
77 int type_stack_depth
, type_stack_size
;
84 static int expressiondebug
= 0;
86 extern int hp_som_som_object_present
;
88 static void free_funcalls (void *ignore
);
90 static void prefixify_expression (struct expression
*);
93 prefixify_subexp (struct expression
*, struct expression
*, int, int);
95 void _initialize_parse (void);
97 /* Data structure for saving values of arglist_len for function calls whose
98 arguments contain other function calls. */
102 struct funcall
*next
;
106 static struct funcall
*funcall_chain
;
108 /* The generic method for targets to specify how their registers are
109 named. The mapping can be derived from two sources: REGISTER_NAME;
113 target_map_name_to_register (char *str
, int len
)
117 /* Search register name space. */
118 for (i
= 0; i
< NUM_REGS
+ NUM_PSEUDO_REGS
; i
++)
119 if (REGISTER_NAME (i
) && len
== strlen (REGISTER_NAME (i
))
120 && STREQN (str
, REGISTER_NAME (i
), len
))
125 /* Try builtin registers. */
126 i
= builtin_reg_map_name_to_regnum (str
, len
);
129 gdb_assert (i
>= NUM_REGS
+ NUM_PSEUDO_REGS
);
133 /* Try builtin registers. */
134 i
= builtin_reg_map_name_to_regnum (str
, len
);
137 gdb_assert (i
>= NUM_REGS
+ NUM_PSEUDO_REGS
);
144 /* Begin counting arguments for a function call,
145 saving the data about any containing call. */
150 register struct funcall
*new;
152 new = (struct funcall
*) xmalloc (sizeof (struct funcall
));
153 new->next
= funcall_chain
;
154 new->arglist_len
= arglist_len
;
159 /* Return the number of arguments in a function call just terminated,
160 and restore the data for the containing function call. */
165 register int val
= arglist_len
;
166 register struct funcall
*call
= funcall_chain
;
167 funcall_chain
= call
->next
;
168 arglist_len
= call
->arglist_len
;
173 /* Free everything in the funcall chain.
174 Used when there is an error inside parsing. */
177 free_funcalls (void *ignore
)
179 register struct funcall
*call
, *next
;
181 for (call
= funcall_chain
; call
; call
= next
)
188 /* This page contains the functions for adding data to the struct expression
189 being constructed. */
191 /* Add one element to the end of the expression. */
193 /* To avoid a bug in the Sun 4 compiler, we pass things that can fit into
194 a register through here */
197 write_exp_elt (union exp_element expelt
)
199 if (expout_ptr
>= expout_size
)
202 expout
= (struct expression
*)
203 xrealloc ((char *) expout
, sizeof (struct expression
)
204 + EXP_ELEM_TO_BYTES (expout_size
));
206 expout
->elts
[expout_ptr
++] = expelt
;
210 write_exp_elt_opcode (enum exp_opcode expelt
)
212 union exp_element tmp
;
220 write_exp_elt_sym (struct symbol
*expelt
)
222 union exp_element tmp
;
230 write_exp_elt_block (struct block
*b
)
232 union exp_element tmp
;
238 write_exp_elt_longcst (LONGEST expelt
)
240 union exp_element tmp
;
242 tmp
.longconst
= expelt
;
248 write_exp_elt_dblcst (DOUBLEST expelt
)
250 union exp_element tmp
;
252 tmp
.doubleconst
= expelt
;
258 write_exp_elt_type (struct type
*expelt
)
260 union exp_element tmp
;
268 write_exp_elt_intern (struct internalvar
*expelt
)
270 union exp_element tmp
;
272 tmp
.internalvar
= expelt
;
277 /* Add a string constant to the end of the expression.
279 String constants are stored by first writing an expression element
280 that contains the length of the string, then stuffing the string
281 constant itself into however many expression elements are needed
282 to hold it, and then writing another expression element that contains
283 the length of the string. I.E. an expression element at each end of
284 the string records the string length, so you can skip over the
285 expression elements containing the actual string bytes from either
286 end of the string. Note that this also allows gdb to handle
287 strings with embedded null bytes, as is required for some languages.
289 Don't be fooled by the fact that the string is null byte terminated,
290 this is strictly for the convenience of debugging gdb itself. Gdb
291 Gdb does not depend up the string being null terminated, since the
292 actual length is recorded in expression elements at each end of the
293 string. The null byte is taken into consideration when computing how
294 many expression elements are required to hold the string constant, of
299 write_exp_string (struct stoken str
)
301 register int len
= str
.length
;
303 register char *strdata
;
305 /* Compute the number of expression elements required to hold the string
306 (including a null byte terminator), along with one expression element
307 at each end to record the actual string length (not including the
308 null byte terminator). */
310 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
+ 1);
312 /* Ensure that we have enough available expression elements to store
315 if ((expout_ptr
+ lenelt
) >= expout_size
)
317 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
318 expout
= (struct expression
*)
319 xrealloc ((char *) expout
, (sizeof (struct expression
)
320 + EXP_ELEM_TO_BYTES (expout_size
)));
323 /* Write the leading length expression element (which advances the current
324 expression element index), then write the string constant followed by a
325 terminating null byte, and then write the trailing length expression
328 write_exp_elt_longcst ((LONGEST
) len
);
329 strdata
= (char *) &expout
->elts
[expout_ptr
];
330 memcpy (strdata
, str
.ptr
, len
);
331 *(strdata
+ len
) = '\0';
332 expout_ptr
+= lenelt
- 2;
333 write_exp_elt_longcst ((LONGEST
) len
);
336 /* Add a bitstring constant to the end of the expression.
338 Bitstring constants are stored by first writing an expression element
339 that contains the length of the bitstring (in bits), then stuffing the
340 bitstring constant itself into however many expression elements are
341 needed to hold it, and then writing another expression element that
342 contains the length of the bitstring. I.E. an expression element at
343 each end of the bitstring records the bitstring length, so you can skip
344 over the expression elements containing the actual bitstring bytes from
345 either end of the bitstring. */
348 write_exp_bitstring (struct stoken str
)
350 register int bits
= str
.length
; /* length in bits */
351 register int len
= (bits
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
353 register char *strdata
;
355 /* Compute the number of expression elements required to hold the bitstring,
356 along with one expression element at each end to record the actual
357 bitstring length in bits. */
359 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
);
361 /* Ensure that we have enough available expression elements to store
364 if ((expout_ptr
+ lenelt
) >= expout_size
)
366 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
367 expout
= (struct expression
*)
368 xrealloc ((char *) expout
, (sizeof (struct expression
)
369 + EXP_ELEM_TO_BYTES (expout_size
)));
372 /* Write the leading length expression element (which advances the current
373 expression element index), then write the bitstring constant, and then
374 write the trailing length expression element. */
376 write_exp_elt_longcst ((LONGEST
) bits
);
377 strdata
= (char *) &expout
->elts
[expout_ptr
];
378 memcpy (strdata
, str
.ptr
, len
);
379 expout_ptr
+= lenelt
- 2;
380 write_exp_elt_longcst ((LONGEST
) bits
);
383 /* Add the appropriate elements for a minimal symbol to the end of
384 the expression. The rationale behind passing in text_symbol_type and
385 data_symbol_type was so that Modula-2 could pass in WORD for
386 data_symbol_type. Perhaps it still is useful to have those types vary
387 based on the language, but they no longer have names like "int", so
388 the initial rationale is gone. */
390 static struct type
*msym_text_symbol_type
;
391 static struct type
*msym_data_symbol_type
;
392 static struct type
*msym_unknown_symbol_type
;
395 write_exp_msymbol (struct minimal_symbol
*msymbol
,
396 struct type
*text_symbol_type
,
397 struct type
*data_symbol_type
)
401 write_exp_elt_opcode (OP_LONG
);
402 /* Let's make the type big enough to hold a 64-bit address. */
403 write_exp_elt_type (builtin_type_CORE_ADDR
);
405 addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
406 if (overlay_debugging
)
407 addr
= symbol_overlayed_address (addr
, SYMBOL_BFD_SECTION (msymbol
));
408 write_exp_elt_longcst ((LONGEST
) addr
);
410 write_exp_elt_opcode (OP_LONG
);
412 write_exp_elt_opcode (UNOP_MEMVAL
);
413 switch (msymbol
->type
)
417 case mst_solib_trampoline
:
418 write_exp_elt_type (msym_text_symbol_type
);
425 write_exp_elt_type (msym_data_symbol_type
);
429 write_exp_elt_type (msym_unknown_symbol_type
);
432 write_exp_elt_opcode (UNOP_MEMVAL
);
435 /* Recognize tokens that start with '$'. These include:
437 $regname A native register name or a "standard
440 $variable A convenience variable with a name chosen
443 $digits Value history with index <digits>, starting
444 from the first value which has index 1.
446 $$digits Value history with index <digits> relative
447 to the last value. I.E. $$0 is the last
448 value, $$1 is the one previous to that, $$2
449 is the one previous to $$1, etc.
451 $ | $0 | $$0 The last value in the value history.
453 $$ An abbreviation for the second to the last
454 value in the value history, I.E. $$1
459 write_dollar_variable (struct stoken str
)
461 /* Handle the tokens $digits; also $ (short for $0) and $$ (short for $$1)
462 and $$digits (equivalent to $<-digits> if you could type that). */
466 /* Double dollar means negate the number and add -1 as well.
467 Thus $$ alone means -1. */
468 if (str
.length
>= 2 && str
.ptr
[1] == '$')
475 /* Just dollars (one or two) */
479 /* Is the rest of the token digits? */
480 for (; i
< str
.length
; i
++)
481 if (!(str
.ptr
[i
] >= '0' && str
.ptr
[i
] <= '9'))
485 i
= atoi (str
.ptr
+ 1 + negate
);
491 /* Handle tokens that refer to machine registers:
492 $ followed by a register name. */
493 i
= target_map_name_to_register (str
.ptr
+ 1, str
.length
- 1);
495 goto handle_register
;
497 if (SYMBOLS_CAN_START_WITH_DOLLAR
)
499 struct symbol
*sym
= NULL
;
500 struct minimal_symbol
*msym
= NULL
;
502 /* On HP-UX, certain system routines (millicode) have names beginning
503 with $ or $$, e.g. $$dyncall, which handles inter-space procedure
504 calls on PA-RISC. Check for those, first. */
506 /* This code is not enabled on non HP-UX systems, since worst case
507 symbol table lookup performance is awful, to put it mildly. */
509 sym
= lookup_symbol (copy_name (str
), (struct block
*) NULL
,
510 VAR_NAMESPACE
, (int *) NULL
, (struct symtab
**) NULL
);
513 write_exp_elt_opcode (OP_VAR_VALUE
);
514 write_exp_elt_block (block_found
); /* set by lookup_symbol */
515 write_exp_elt_sym (sym
);
516 write_exp_elt_opcode (OP_VAR_VALUE
);
519 msym
= lookup_minimal_symbol (copy_name (str
), NULL
, NULL
);
522 write_exp_msymbol (msym
,
523 lookup_function_type (builtin_type_int
),
529 /* Any other names starting in $ are debugger internal variables. */
531 write_exp_elt_opcode (OP_INTERNALVAR
);
532 write_exp_elt_intern (lookup_internalvar (copy_name (str
) + 1));
533 write_exp_elt_opcode (OP_INTERNALVAR
);
536 write_exp_elt_opcode (OP_LAST
);
537 write_exp_elt_longcst ((LONGEST
) i
);
538 write_exp_elt_opcode (OP_LAST
);
541 write_exp_elt_opcode (OP_REGISTER
);
542 write_exp_elt_longcst (i
);
543 write_exp_elt_opcode (OP_REGISTER
);
548 /* Parse a string that is possibly a namespace / nested class
549 specification, i.e., something of the form A::B::C::x. Input
550 (NAME) is the entire string; LEN is the current valid length; the
551 output is a string, TOKEN, which points to the largest recognized
552 prefix which is a series of namespaces or classes. CLASS_PREFIX is
553 another output, which records whether a nested class spec was
554 recognized (= 1) or a fully qualified variable name was found (=
555 0). ARGPTR is side-effected (if non-NULL) to point to beyond the
556 string recognized and consumed by this routine.
558 The return value is a pointer to the symbol for the base class or
559 variable if found, or NULL if not found. Callers must check this
560 first -- if NULL, the outputs may not be correct.
562 This function is used c-exp.y. This is used specifically to get
563 around HP aCC (and possibly other compilers), which insists on
564 generating names with embedded colons for namespace or nested class
567 (Argument LEN is currently unused. 1997-08-27)
569 Callers must free memory allocated for the output string TOKEN. */
571 static const char coloncolon
[2] =
575 parse_nested_classes_for_hpacc (char *name
, int len
, char **token
,
576 int *class_prefix
, char **argptr
)
578 /* Comment below comes from decode_line_1 which has very similar
579 code, which is called for "break" command parsing. */
581 /* We have what looks like a class or namespace
582 scope specification (A::B), possibly with many
583 levels of namespaces or classes (A::B::C::D).
585 Some versions of the HP ANSI C++ compiler (as also possibly
586 other compilers) generate class/function/member names with
587 embedded double-colons if they are inside namespaces. To
588 handle this, we loop a few times, considering larger and
589 larger prefixes of the string as though they were single
590 symbols. So, if the initially supplied string is
591 A::B::C::D::foo, we have to look up "A", then "A::B",
592 then "A::B::C", then "A::B::C::D", and finally
593 "A::B::C::D::foo" as single, monolithic symbols, because
594 A, B, C or D may be namespaces.
596 Note that namespaces can nest only inside other
597 namespaces, and not inside classes. So we need only
598 consider *prefixes* of the string; there is no need to look up
599 "B::C" separately as a symbol in the previous example. */
605 struct symbol
*sym_class
= NULL
;
606 struct symbol
*sym_var
= NULL
;
612 /* Check for HP-compiled executable -- in other cases
613 return NULL, and caller must default to standard GDB
616 if (!hp_som_som_object_present
)
617 return (struct symbol
*) NULL
;
621 /* Skip over whitespace and possible global "::" */
622 while (*p
&& (*p
== ' ' || *p
== '\t'))
624 if (p
[0] == ':' && p
[1] == ':')
626 while (*p
&& (*p
== ' ' || *p
== '\t'))
631 /* Get to the end of the next namespace or class spec. */
632 /* If we're looking at some non-token, fail immediately */
634 if (!(isalpha (*p
) || *p
== '$' || *p
== '_'))
635 return (struct symbol
*) NULL
;
637 while (*p
&& (isalnum (*p
) || *p
== '$' || *p
== '_'))
642 /* If we have the start of a template specification,
643 scan right ahead to its end */
644 q
= find_template_name_end (p
);
651 /* Skip over "::" and whitespace for next time around */
652 while (*p
&& (*p
== ' ' || *p
== '\t'))
654 if (p
[0] == ':' && p
[1] == ':')
656 while (*p
&& (*p
== ' ' || *p
== '\t'))
659 /* Done with tokens? */
660 if (!*p
|| !(isalpha (*p
) || *p
== '$' || *p
== '_'))
663 tmp
= (char *) alloca (prefix_len
+ end
- start
+ 3);
666 memcpy (tmp
, prefix
, prefix_len
);
667 memcpy (tmp
+ prefix_len
, coloncolon
, 2);
668 memcpy (tmp
+ prefix_len
+ 2, start
, end
- start
);
669 tmp
[prefix_len
+ 2 + end
- start
] = '\000';
673 memcpy (tmp
, start
, end
- start
);
674 tmp
[end
- start
] = '\000';
678 prefix_len
= strlen (prefix
);
680 /* See if the prefix we have now is something we know about */
684 /* More tokens to process, so this must be a class/namespace */
685 sym_class
= lookup_symbol (prefix
, 0, STRUCT_NAMESPACE
,
686 0, (struct symtab
**) NULL
);
690 /* No more tokens, so try as a variable first */
691 sym_var
= lookup_symbol (prefix
, 0, VAR_NAMESPACE
,
692 0, (struct symtab
**) NULL
);
693 /* If failed, try as class/namespace */
695 sym_class
= lookup_symbol (prefix
, 0, STRUCT_NAMESPACE
,
696 0, (struct symtab
**) NULL
);
701 (t
= check_typedef (SYMBOL_TYPE (sym_class
)),
702 (TYPE_CODE (t
) == TYPE_CODE_STRUCT
703 || TYPE_CODE (t
) == TYPE_CODE_UNION
))))
705 /* We found a valid token */
706 *token
= (char *) xmalloc (prefix_len
+ 1);
707 memcpy (*token
, prefix
, prefix_len
);
708 (*token
)[prefix_len
] = '\000';
712 /* No variable or class/namespace found, no more tokens */
714 return (struct symbol
*) NULL
;
717 /* Out of loop, so we must have found a valid token */
724 *argptr
= done
? p
: end
;
726 return sym_var
? sym_var
: sym_class
; /* found */
730 find_template_name_end (char *p
)
733 int just_seen_right
= 0;
734 int just_seen_colon
= 0;
735 int just_seen_space
= 0;
737 if (!p
|| (*p
!= '<'))
748 /* In future, may want to allow these?? */
751 depth
++; /* start nested template */
752 if (just_seen_colon
|| just_seen_right
|| just_seen_space
)
753 return 0; /* but not after : or :: or > or space */
756 if (just_seen_colon
|| just_seen_right
)
757 return 0; /* end a (nested?) template */
758 just_seen_right
= 1; /* but not after : or :: */
759 if (--depth
== 0) /* also disallow >>, insist on > > */
760 return ++p
; /* if outermost ended, return */
763 if (just_seen_space
|| (just_seen_colon
> 1))
764 return 0; /* nested class spec coming up */
765 just_seen_colon
++; /* we allow :: but not :::: */
770 if (!((*p
>= 'a' && *p
<= 'z') || /* allow token chars */
771 (*p
>= 'A' && *p
<= 'Z') ||
772 (*p
>= '0' && *p
<= '9') ||
773 (*p
== '_') || (*p
== ',') || /* commas for template args */
774 (*p
== '&') || (*p
== '*') || /* pointer and ref types */
775 (*p
== '(') || (*p
== ')') || /* function types */
776 (*p
== '[') || (*p
== ']'))) /* array types */
791 /* Return a null-terminated temporary copy of the name
792 of a string token. */
795 copy_name (struct stoken token
)
797 memcpy (namecopy
, token
.ptr
, token
.length
);
798 namecopy
[token
.length
] = 0;
802 /* Reverse an expression from suffix form (in which it is constructed)
803 to prefix form (in which we can conveniently print or execute it). */
806 prefixify_expression (register struct expression
*expr
)
809 sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expr
->nelts
);
810 register struct expression
*temp
;
811 register int inpos
= expr
->nelts
, outpos
= 0;
813 temp
= (struct expression
*) alloca (len
);
815 /* Copy the original expression into temp. */
816 memcpy (temp
, expr
, len
);
818 prefixify_subexp (temp
, expr
, inpos
, outpos
);
821 /* Return the number of exp_elements in the subexpression of EXPR
822 whose last exp_element is at index ENDPOS - 1 in EXPR. */
825 length_of_subexp (register struct expression
*expr
, register int endpos
)
827 register int oplen
= 1;
828 register int args
= 0;
832 error ("?error in length_of_subexp");
834 i
= (int) expr
->elts
[endpos
- 1].opcode
;
840 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
841 oplen
= 5 + BYTES_TO_EXP_ELEM (oplen
+ 1);
864 case OP_F77_UNDETERMINED_ARGLIST
:
866 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
894 case STRUCTOP_STRUCT
:
902 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
903 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
907 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
908 oplen
= (oplen
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
909 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
);
914 args
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
915 args
-= longest_to_int (expr
->elts
[endpos
- 3].longconst
);
921 case TERNOP_SLICE_COUNT
:
926 case MULTI_SUBSCRIPT
:
928 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
931 case BINOP_ASSIGN_MODIFY
:
942 args
= 1 + (i
< (int) BINOP_END
);
947 oplen
+= length_of_subexp (expr
, endpos
- oplen
);
954 /* Copy the subexpression ending just before index INEND in INEXPR
955 into OUTEXPR, starting at index OUTBEG.
956 In the process, convert it from suffix to prefix form. */
959 prefixify_subexp (register struct expression
*inexpr
,
960 struct expression
*outexpr
, register int inend
, int outbeg
)
962 register int oplen
= 1;
963 register int args
= 0;
966 enum exp_opcode opcode
;
968 /* Compute how long the last operation is (in OPLEN),
969 and also how many preceding subexpressions serve as
970 arguments for it (in ARGS). */
972 opcode
= inexpr
->elts
[inend
- 1].opcode
;
977 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
978 oplen
= 5 + BYTES_TO_EXP_ELEM (oplen
+ 1);
1001 case OP_F77_UNDETERMINED_ARGLIST
:
1003 args
= 1 + longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1029 case STRUCTOP_STRUCT
:
1038 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1039 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
1043 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1044 oplen
= (oplen
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
1045 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
);
1050 args
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1051 args
-= longest_to_int (inexpr
->elts
[inend
- 3].longconst
);
1057 case TERNOP_SLICE_COUNT
:
1061 case BINOP_ASSIGN_MODIFY
:
1067 case MULTI_SUBSCRIPT
:
1069 args
= 1 + longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1078 args
= 1 + ((int) opcode
< (int) BINOP_END
);
1081 /* Copy the final operator itself, from the end of the input
1082 to the beginning of the output. */
1084 memcpy (&outexpr
->elts
[outbeg
], &inexpr
->elts
[inend
],
1085 EXP_ELEM_TO_BYTES (oplen
));
1088 /* Find the lengths of the arg subexpressions. */
1089 arglens
= (int *) alloca (args
* sizeof (int));
1090 for (i
= args
- 1; i
>= 0; i
--)
1092 oplen
= length_of_subexp (inexpr
, inend
);
1097 /* Now copy each subexpression, preserving the order of
1098 the subexpressions, but prefixifying each one.
1099 In this loop, inend starts at the beginning of
1100 the expression this level is working on
1101 and marches forward over the arguments.
1102 outbeg does similarly in the output. */
1103 for (i
= 0; i
< args
; i
++)
1107 prefixify_subexp (inexpr
, outexpr
, inend
, outbeg
);
1112 /* This page contains the two entry points to this file. */
1114 /* Read an expression from the string *STRINGPTR points to,
1115 parse it, and return a pointer to a struct expression that we malloc.
1116 Use block BLOCK as the lexical context for variable names;
1117 if BLOCK is zero, use the block of the selected stack frame.
1118 Meanwhile, advance *STRINGPTR to point after the expression,
1119 at the first nonwhite character that is not part of the expression
1120 (possibly a null character).
1122 If COMMA is nonzero, stop if a comma is reached. */
1125 parse_exp_1 (char **stringptr
, struct block
*block
, int comma
)
1127 struct cleanup
*old_chain
;
1129 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 (free_funcalls
, 0 /*ignore*/);
1143 expression_context_block
= block
? block
: get_selected_block (0);
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 (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_stdlog
,
1172 "before conversion to prefix form");
1174 prefixify_expression (expout
);
1176 if (expressiondebug
)
1177 dump_postfix_expression (expout
, gdb_stdlog
,
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 (char *string
)
1190 register struct expression
*exp
;
1191 exp
= parse_exp_1 (&string
, 0, 0);
1193 error ("Junk after end of expression.");
1197 /* Stuff for maintaining a stack of types. Currently just used by C, but
1198 probably useful for any language which declares its types "backwards". */
1201 check_type_stack_depth (void)
1203 if (type_stack_depth
== type_stack_size
)
1205 type_stack_size
*= 2;
1206 type_stack
= (union type_stack_elt
*)
1207 xrealloc ((char *) type_stack
, type_stack_size
* sizeof (*type_stack
));
1212 push_type (enum type_pieces tp
)
1214 check_type_stack_depth ();
1215 type_stack
[type_stack_depth
++].piece
= tp
;
1219 push_type_int (int n
)
1221 check_type_stack_depth ();
1222 type_stack
[type_stack_depth
++].int_val
= n
;
1226 push_type_address_space (char *string
)
1228 push_type_int (address_space_name_to_int (string
));
1234 if (type_stack_depth
)
1235 return type_stack
[--type_stack_depth
].piece
;
1242 if (type_stack_depth
)
1243 return type_stack
[--type_stack_depth
].int_val
;
1244 /* "Can't happen". */
1248 /* Pop the type stack and return the type which corresponds to FOLLOW_TYPE
1249 as modified by all the stuff on the stack. */
1251 follow_types (struct type
*follow_type
)
1255 int make_volatile
= 0;
1256 int make_addr_space
= 0;
1258 struct type
*range_type
;
1261 switch (pop_type ())
1266 follow_type
= make_cv_type (make_const
,
1267 TYPE_VOLATILE (follow_type
),
1270 follow_type
= make_cv_type (TYPE_CONST (follow_type
),
1273 if (make_addr_space
)
1274 follow_type
= make_type_with_address_space (follow_type
,
1276 make_const
= make_volatile
= 0;
1277 make_addr_space
= 0;
1285 case tp_space_identifier
:
1286 make_addr_space
= pop_type_int ();
1289 follow_type
= lookup_pointer_type (follow_type
);
1291 follow_type
= make_cv_type (make_const
,
1292 TYPE_VOLATILE (follow_type
),
1295 follow_type
= make_cv_type (TYPE_CONST (follow_type
),
1298 if (make_addr_space
)
1299 follow_type
= make_type_with_address_space (follow_type
,
1301 make_const
= make_volatile
= 0;
1302 make_addr_space
= 0;
1305 follow_type
= lookup_reference_type (follow_type
);
1307 follow_type
= make_cv_type (make_const
,
1308 TYPE_VOLATILE (follow_type
),
1311 follow_type
= make_cv_type (TYPE_CONST (follow_type
),
1314 if (make_addr_space
)
1315 follow_type
= make_type_with_address_space (follow_type
,
1317 make_const
= make_volatile
= 0;
1318 make_addr_space
= 0;
1321 array_size
= pop_type_int ();
1322 /* FIXME-type-allocation: need a way to free this type when we are
1325 create_range_type ((struct type
*) NULL
,
1326 builtin_type_int
, 0,
1327 array_size
>= 0 ? array_size
- 1 : 0);
1329 create_array_type ((struct type
*) NULL
,
1330 follow_type
, range_type
);
1332 TYPE_ARRAY_UPPER_BOUND_TYPE (follow_type
)
1333 = BOUND_CANNOT_BE_DETERMINED
;
1336 /* FIXME-type-allocation: need a way to free this type when we are
1338 follow_type
= lookup_function_type (follow_type
);
1344 static void build_parse (void);
1350 msym_text_symbol_type
=
1351 init_type (TYPE_CODE_FUNC
, 1, 0, "<text variable, no debug info>", NULL
);
1352 TYPE_TARGET_TYPE (msym_text_symbol_type
) = builtin_type_int
;
1353 msym_data_symbol_type
=
1354 init_type (TYPE_CODE_INT
, TARGET_INT_BIT
/ HOST_CHAR_BIT
, 0,
1355 "<data variable, no debug info>", NULL
);
1356 msym_unknown_symbol_type
=
1357 init_type (TYPE_CODE_INT
, 1, 0,
1358 "<variable (not text or data), no debug info>",
1363 _initialize_parse (void)
1365 type_stack_size
= 80;
1366 type_stack_depth
= 0;
1367 type_stack
= (union type_stack_elt
*)
1368 xmalloc (type_stack_size
* sizeof (*type_stack
));
1372 /* FIXME - For the moment, handle types by swapping them in and out.
1373 Should be using the per-architecture data-pointer and a large
1375 register_gdbarch_swap (&msym_text_symbol_type
, sizeof (msym_text_symbol_type
), NULL
);
1376 register_gdbarch_swap (&msym_data_symbol_type
, sizeof (msym_data_symbol_type
), NULL
);
1377 register_gdbarch_swap (&msym_unknown_symbol_type
, sizeof (msym_unknown_symbol_type
), NULL
);
1379 register_gdbarch_swap (NULL
, 0, build_parse
);
1382 add_set_cmd ("expression", class_maintenance
, var_zinteger
,
1383 (char *) &expressiondebug
,
1384 "Set expression debugging.\n\
1385 When non-zero, the internal representation of expressions will be printed.",