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,
21 Boston, MA 02111-1307, USA. */
23 /* Parse an expression from text in a string,
24 and return the result as a struct expression pointer.
25 That structure contains arithmetic operations in reverse polish,
26 with constants represented by operations that are followed by special data.
27 See expression.h for the details of the format.
28 What is important here is that it can be built up sequentially
29 during the process of parsing; the lower levels of the tree always
30 come first in the result. */
35 #include "gdb_string.h"
39 #include "expression.h"
43 #include "parser-defs.h"
45 #include "symfile.h" /* for overlay functions */
46 #include "inferior.h" /* for NUM_PSEUDO_REGS. NOTE: replace
47 with "gdbarch.h" when appropriate. */
50 /* Symbols which architectures can redefine. */
52 /* Some systems have routines whose names start with `$'. Giving this
53 macro a non-zero value tells GDB's expression parser to check for
54 such routines when parsing tokens that begin with `$'.
56 On HP-UX, certain system routines (millicode) have names beginning
57 with `$' or `$$'. For example, `$$dyncall' is a millicode routine
58 that handles inter-space procedure calls on PA-RISC. */
59 #ifndef SYMBOLS_CAN_START_WITH_DOLLAR
60 #define SYMBOLS_CAN_START_WITH_DOLLAR (0)
65 /* Global variables declared in parser-defs.h (and commented there). */
66 struct expression
*expout
;
69 struct block
*expression_context_block
;
70 struct block
*innermost_block
;
72 union type_stack_elt
*type_stack
;
73 int type_stack_depth
, type_stack_size
;
79 static int expressiondebug
= 0;
81 extern int hp_som_som_object_present
;
83 static void free_funcalls (void *ignore
);
85 static void prefixify_expression (struct expression
*);
88 prefixify_subexp (struct expression
*, struct expression
*, int, int);
90 void _initialize_parse (void);
92 /* Data structure for saving values of arglist_len for function calls whose
93 arguments contain other function calls. */
101 static struct funcall
*funcall_chain
;
103 /* Assign machine-independent names to certain registers
104 (unless overridden by the REGISTER_NAMES table) */
106 unsigned num_std_regs
= 0;
107 struct std_regs
*std_regs
;
109 /* The generic method for targets to specify how their registers are
110 named. The mapping can be derived from three sources:
111 REGISTER_NAME; std_regs; or a target specific alias hook. */
114 target_map_name_to_register (str
, len
)
120 /* First try target specific aliases. We try these first because on some
121 systems standard names can be context dependent (eg. $pc on a
122 multiprocessor can be could be any of several PCs). */
123 #ifdef REGISTER_NAME_ALIAS_HOOK
124 i
= REGISTER_NAME_ALIAS_HOOK (str
, len
);
129 /* Search architectural register name space. */
130 for (i
= 0; i
< NUM_REGS
; i
++)
131 if (REGISTER_NAME (i
) && len
== strlen (REGISTER_NAME (i
))
132 && STREQN (str
, REGISTER_NAME (i
), len
))
137 /* Try pseudo-registers, if any. */
138 for (i
= NUM_REGS
; i
< NUM_REGS
+ NUM_PSEUDO_REGS
; i
++)
139 if (REGISTER_NAME (i
) && len
== strlen (REGISTER_NAME (i
))
140 && STREQN (str
, REGISTER_NAME (i
), len
))
145 /* Try standard aliases. */
146 for (i
= 0; i
< num_std_regs
; i
++)
147 if (std_regs
[i
].name
&& len
== strlen (std_regs
[i
].name
)
148 && STREQN (str
, std_regs
[i
].name
, len
))
150 return std_regs
[i
].regnum
;
156 /* Begin counting arguments for a function call,
157 saving the data about any containing call. */
162 register struct funcall
*new;
164 new = (struct funcall
*) xmalloc (sizeof (struct funcall
));
165 new->next
= funcall_chain
;
166 new->arglist_len
= arglist_len
;
171 /* Return the number of arguments in a function call just terminated,
172 and restore the data for the containing function call. */
177 register int val
= arglist_len
;
178 register struct funcall
*call
= funcall_chain
;
179 funcall_chain
= call
->next
;
180 arglist_len
= call
->arglist_len
;
185 /* Free everything in the funcall chain.
186 Used when there is an error inside parsing. */
189 free_funcalls (void *ignore
)
191 register struct funcall
*call
, *next
;
193 for (call
= funcall_chain
; call
; call
= next
)
200 /* This page contains the functions for adding data to the struct expression
201 being constructed. */
203 /* Add one element to the end of the expression. */
205 /* To avoid a bug in the Sun 4 compiler, we pass things that can fit into
206 a register through here */
209 write_exp_elt (expelt
)
210 union exp_element expelt
;
212 if (expout_ptr
>= expout_size
)
215 expout
= (struct expression
*)
216 xrealloc ((char *) expout
, sizeof (struct expression
)
217 + EXP_ELEM_TO_BYTES (expout_size
));
219 expout
->elts
[expout_ptr
++] = expelt
;
223 write_exp_elt_opcode (expelt
)
224 enum exp_opcode expelt
;
226 union exp_element tmp
;
234 write_exp_elt_sym (expelt
)
235 struct symbol
*expelt
;
237 union exp_element tmp
;
245 write_exp_elt_block (b
)
248 union exp_element tmp
;
254 write_exp_elt_longcst (expelt
)
257 union exp_element tmp
;
259 tmp
.longconst
= expelt
;
265 write_exp_elt_dblcst (expelt
)
268 union exp_element tmp
;
270 tmp
.doubleconst
= expelt
;
276 write_exp_elt_type (expelt
)
279 union exp_element tmp
;
287 write_exp_elt_intern (expelt
)
288 struct internalvar
*expelt
;
290 union exp_element tmp
;
292 tmp
.internalvar
= expelt
;
297 /* Add a string constant to the end of the expression.
299 String constants are stored by first writing an expression element
300 that contains the length of the string, then stuffing the string
301 constant itself into however many expression elements are needed
302 to hold it, and then writing another expression element that contains
303 the length of the string. I.E. an expression element at each end of
304 the string records the string length, so you can skip over the
305 expression elements containing the actual string bytes from either
306 end of the string. Note that this also allows gdb to handle
307 strings with embedded null bytes, as is required for some languages.
309 Don't be fooled by the fact that the string is null byte terminated,
310 this is strictly for the convenience of debugging gdb itself. Gdb
311 Gdb does not depend up the string being null terminated, since the
312 actual length is recorded in expression elements at each end of the
313 string. The null byte is taken into consideration when computing how
314 many expression elements are required to hold the string constant, of
319 write_exp_string (str
)
322 register int len
= str
.length
;
324 register char *strdata
;
326 /* Compute the number of expression elements required to hold the string
327 (including a null byte terminator), along with one expression element
328 at each end to record the actual string length (not including the
329 null byte terminator). */
331 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
+ 1);
333 /* Ensure that we have enough available expression elements to store
336 if ((expout_ptr
+ lenelt
) >= expout_size
)
338 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
339 expout
= (struct expression
*)
340 xrealloc ((char *) expout
, (sizeof (struct expression
)
341 + EXP_ELEM_TO_BYTES (expout_size
)));
344 /* Write the leading length expression element (which advances the current
345 expression element index), then write the string constant followed by a
346 terminating null byte, and then write the trailing length expression
349 write_exp_elt_longcst ((LONGEST
) len
);
350 strdata
= (char *) &expout
->elts
[expout_ptr
];
351 memcpy (strdata
, str
.ptr
, len
);
352 *(strdata
+ len
) = '\0';
353 expout_ptr
+= lenelt
- 2;
354 write_exp_elt_longcst ((LONGEST
) len
);
357 /* Add a bitstring constant to the end of the expression.
359 Bitstring constants are stored by first writing an expression element
360 that contains the length of the bitstring (in bits), then stuffing the
361 bitstring constant itself into however many expression elements are
362 needed to hold it, and then writing another expression element that
363 contains the length of the bitstring. I.E. an expression element at
364 each end of the bitstring records the bitstring length, so you can skip
365 over the expression elements containing the actual bitstring bytes from
366 either end of the bitstring. */
369 write_exp_bitstring (str
)
372 register int bits
= str
.length
; /* length in bits */
373 register int len
= (bits
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
375 register char *strdata
;
377 /* Compute the number of expression elements required to hold the bitstring,
378 along with one expression element at each end to record the actual
379 bitstring length in bits. */
381 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
);
383 /* Ensure that we have enough available expression elements to store
386 if ((expout_ptr
+ lenelt
) >= expout_size
)
388 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
389 expout
= (struct expression
*)
390 xrealloc ((char *) expout
, (sizeof (struct expression
)
391 + EXP_ELEM_TO_BYTES (expout_size
)));
394 /* Write the leading length expression element (which advances the current
395 expression element index), then write the bitstring constant, and then
396 write the trailing length expression element. */
398 write_exp_elt_longcst ((LONGEST
) bits
);
399 strdata
= (char *) &expout
->elts
[expout_ptr
];
400 memcpy (strdata
, str
.ptr
, len
);
401 expout_ptr
+= lenelt
- 2;
402 write_exp_elt_longcst ((LONGEST
) bits
);
405 /* Add the appropriate elements for a minimal symbol to the end of
406 the expression. The rationale behind passing in text_symbol_type and
407 data_symbol_type was so that Modula-2 could pass in WORD for
408 data_symbol_type. Perhaps it still is useful to have those types vary
409 based on the language, but they no longer have names like "int", so
410 the initial rationale is gone. */
412 static struct type
*msym_text_symbol_type
;
413 static struct type
*msym_data_symbol_type
;
414 static struct type
*msym_unknown_symbol_type
;
417 write_exp_msymbol (msymbol
, text_symbol_type
, data_symbol_type
)
418 struct minimal_symbol
*msymbol
;
419 struct type
*text_symbol_type
;
420 struct type
*data_symbol_type
;
424 write_exp_elt_opcode (OP_LONG
);
425 write_exp_elt_type (lookup_pointer_type (builtin_type_void
));
427 addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
428 if (overlay_debugging
)
429 addr
= symbol_overlayed_address (addr
, SYMBOL_BFD_SECTION (msymbol
));
430 write_exp_elt_longcst ((LONGEST
) addr
);
432 write_exp_elt_opcode (OP_LONG
);
434 write_exp_elt_opcode (UNOP_MEMVAL
);
435 switch (msymbol
->type
)
439 case mst_solib_trampoline
:
440 write_exp_elt_type (msym_text_symbol_type
);
447 write_exp_elt_type (msym_data_symbol_type
);
451 write_exp_elt_type (msym_unknown_symbol_type
);
454 write_exp_elt_opcode (UNOP_MEMVAL
);
457 /* Recognize tokens that start with '$'. These include:
459 $regname A native register name or a "standard
462 $variable A convenience variable with a name chosen
465 $digits Value history with index <digits>, starting
466 from the first value which has index 1.
468 $$digits Value history with index <digits> relative
469 to the last value. I.E. $$0 is the last
470 value, $$1 is the one previous to that, $$2
471 is the one previous to $$1, etc.
473 $ | $0 | $$0 The last value in the value history.
475 $$ An abbreviation for the second to the last
476 value in the value history, I.E. $$1
481 write_dollar_variable (str
)
484 /* Handle the tokens $digits; also $ (short for $0) and $$ (short for $$1)
485 and $$digits (equivalent to $<-digits> if you could type that). */
489 /* Double dollar means negate the number and add -1 as well.
490 Thus $$ alone means -1. */
491 if (str
.length
>= 2 && str
.ptr
[1] == '$')
498 /* Just dollars (one or two) */
502 /* Is the rest of the token digits? */
503 for (; i
< str
.length
; i
++)
504 if (!(str
.ptr
[i
] >= '0' && str
.ptr
[i
] <= '9'))
508 i
= atoi (str
.ptr
+ 1 + negate
);
514 /* Handle tokens that refer to machine registers:
515 $ followed by a register name. */
516 i
= target_map_name_to_register (str
.ptr
+ 1, str
.length
- 1);
518 goto handle_register
;
520 if (SYMBOLS_CAN_START_WITH_DOLLAR
)
522 struct symbol
*sym
= NULL
;
523 struct minimal_symbol
*msym
= NULL
;
525 /* On HP-UX, certain system routines (millicode) have names beginning
526 with $ or $$, e.g. $$dyncall, which handles inter-space procedure
527 calls on PA-RISC. Check for those, first. */
529 /* This code is not enabled on non HP-UX systems, since worst case
530 symbol table lookup performance is awful, to put it mildly. */
532 sym
= lookup_symbol (copy_name (str
), (struct block
*) NULL
,
533 VAR_NAMESPACE
, (int *) NULL
, (struct symtab
**) NULL
);
536 write_exp_elt_opcode (OP_VAR_VALUE
);
537 write_exp_elt_block (block_found
); /* set by lookup_symbol */
538 write_exp_elt_sym (sym
);
539 write_exp_elt_opcode (OP_VAR_VALUE
);
542 msym
= lookup_minimal_symbol (copy_name (str
), NULL
, NULL
);
545 write_exp_msymbol (msym
,
546 lookup_function_type (builtin_type_int
),
552 /* Any other names starting in $ are debugger internal variables. */
554 write_exp_elt_opcode (OP_INTERNALVAR
);
555 write_exp_elt_intern (lookup_internalvar (copy_name (str
) + 1));
556 write_exp_elt_opcode (OP_INTERNALVAR
);
559 write_exp_elt_opcode (OP_LAST
);
560 write_exp_elt_longcst ((LONGEST
) i
);
561 write_exp_elt_opcode (OP_LAST
);
564 write_exp_elt_opcode (OP_REGISTER
);
565 write_exp_elt_longcst (i
);
566 write_exp_elt_opcode (OP_REGISTER
);
571 /* Parse a string that is possibly a namespace / nested class
572 specification, i.e., something of the form A::B::C::x. Input
573 (NAME) is the entire string; LEN is the current valid length; the
574 output is a string, TOKEN, which points to the largest recognized
575 prefix which is a series of namespaces or classes. CLASS_PREFIX is
576 another output, which records whether a nested class spec was
577 recognized (= 1) or a fully qualified variable name was found (=
578 0). ARGPTR is side-effected (if non-NULL) to point to beyond the
579 string recognized and consumed by this routine.
581 The return value is a pointer to the symbol for the base class or
582 variable if found, or NULL if not found. Callers must check this
583 first -- if NULL, the outputs may not be correct.
585 This function is used c-exp.y. This is used specifically to get
586 around HP aCC (and possibly other compilers), which insists on
587 generating names with embedded colons for namespace or nested class
590 (Argument LEN is currently unused. 1997-08-27)
592 Callers must free memory allocated for the output string TOKEN. */
594 static const char coloncolon
[2] =
598 parse_nested_classes_for_hpacc (name
, len
, token
, class_prefix
, argptr
)
605 /* Comment below comes from decode_line_1 which has very similar
606 code, which is called for "break" command parsing. */
608 /* We have what looks like a class or namespace
609 scope specification (A::B), possibly with many
610 levels of namespaces or classes (A::B::C::D).
612 Some versions of the HP ANSI C++ compiler (as also possibly
613 other compilers) generate class/function/member names with
614 embedded double-colons if they are inside namespaces. To
615 handle this, we loop a few times, considering larger and
616 larger prefixes of the string as though they were single
617 symbols. So, if the initially supplied string is
618 A::B::C::D::foo, we have to look up "A", then "A::B",
619 then "A::B::C", then "A::B::C::D", and finally
620 "A::B::C::D::foo" as single, monolithic symbols, because
621 A, B, C or D may be namespaces.
623 Note that namespaces can nest only inside other
624 namespaces, and not inside classes. So we need only
625 consider *prefixes* of the string; there is no need to look up
626 "B::C" separately as a symbol in the previous example. */
632 struct symbol
*sym_class
= NULL
;
633 struct symbol
*sym_var
= NULL
;
639 /* Check for HP-compiled executable -- in other cases
640 return NULL, and caller must default to standard GDB
643 if (!hp_som_som_object_present
)
644 return (struct symbol
*) NULL
;
648 /* Skip over whitespace and possible global "::" */
649 while (*p
&& (*p
== ' ' || *p
== '\t'))
651 if (p
[0] == ':' && p
[1] == ':')
653 while (*p
&& (*p
== ' ' || *p
== '\t'))
658 /* Get to the end of the next namespace or class spec. */
659 /* If we're looking at some non-token, fail immediately */
661 if (!(isalpha (*p
) || *p
== '$' || *p
== '_'))
662 return (struct symbol
*) NULL
;
664 while (*p
&& (isalnum (*p
) || *p
== '$' || *p
== '_'))
669 /* If we have the start of a template specification,
670 scan right ahead to its end */
671 q
= find_template_name_end (p
);
678 /* Skip over "::" and whitespace for next time around */
679 while (*p
&& (*p
== ' ' || *p
== '\t'))
681 if (p
[0] == ':' && p
[1] == ':')
683 while (*p
&& (*p
== ' ' || *p
== '\t'))
686 /* Done with tokens? */
687 if (!*p
|| !(isalpha (*p
) || *p
== '$' || *p
== '_'))
690 tmp
= (char *) alloca (prefix_len
+ end
- start
+ 3);
693 memcpy (tmp
, prefix
, prefix_len
);
694 memcpy (tmp
+ prefix_len
, coloncolon
, 2);
695 memcpy (tmp
+ prefix_len
+ 2, start
, end
- start
);
696 tmp
[prefix_len
+ 2 + end
- start
] = '\000';
700 memcpy (tmp
, start
, end
- start
);
701 tmp
[end
- start
] = '\000';
705 prefix_len
= strlen (prefix
);
707 /* See if the prefix we have now is something we know about */
711 /* More tokens to process, so this must be a class/namespace */
712 sym_class
= lookup_symbol (prefix
, 0, STRUCT_NAMESPACE
,
713 0, (struct symtab
**) NULL
);
717 /* No more tokens, so try as a variable first */
718 sym_var
= lookup_symbol (prefix
, 0, VAR_NAMESPACE
,
719 0, (struct symtab
**) NULL
);
720 /* If failed, try as class/namespace */
722 sym_class
= lookup_symbol (prefix
, 0, STRUCT_NAMESPACE
,
723 0, (struct symtab
**) NULL
);
728 (t
= check_typedef (SYMBOL_TYPE (sym_class
)),
729 (TYPE_CODE (t
) == TYPE_CODE_STRUCT
730 || TYPE_CODE (t
) == TYPE_CODE_UNION
))))
732 /* We found a valid token */
733 *token
= (char *) xmalloc (prefix_len
+ 1);
734 memcpy (*token
, prefix
, prefix_len
);
735 (*token
)[prefix_len
] = '\000';
739 /* No variable or class/namespace found, no more tokens */
741 return (struct symbol
*) NULL
;
744 /* Out of loop, so we must have found a valid token */
751 *argptr
= done
? p
: end
;
753 return sym_var
? sym_var
: sym_class
; /* found */
757 find_template_name_end (p
)
761 int just_seen_right
= 0;
762 int just_seen_colon
= 0;
763 int just_seen_space
= 0;
765 if (!p
|| (*p
!= '<'))
776 /* In future, may want to allow these?? */
779 depth
++; /* start nested template */
780 if (just_seen_colon
|| just_seen_right
|| just_seen_space
)
781 return 0; /* but not after : or :: or > or space */
784 if (just_seen_colon
|| just_seen_right
)
785 return 0; /* end a (nested?) template */
786 just_seen_right
= 1; /* but not after : or :: */
787 if (--depth
== 0) /* also disallow >>, insist on > > */
788 return ++p
; /* if outermost ended, return */
791 if (just_seen_space
|| (just_seen_colon
> 1))
792 return 0; /* nested class spec coming up */
793 just_seen_colon
++; /* we allow :: but not :::: */
798 if (!((*p
>= 'a' && *p
<= 'z') || /* allow token chars */
799 (*p
>= 'A' && *p
<= 'Z') ||
800 (*p
>= '0' && *p
<= '9') ||
801 (*p
== '_') || (*p
== ',') || /* commas for template args */
802 (*p
== '&') || (*p
== '*') || /* pointer and ref types */
803 (*p
== '(') || (*p
== ')') || /* function types */
804 (*p
== '[') || (*p
== ']'))) /* array types */
819 /* Return a null-terminated temporary copy of the name
820 of a string token. */
826 memcpy (namecopy
, token
.ptr
, token
.length
);
827 namecopy
[token
.length
] = 0;
831 /* Reverse an expression from suffix form (in which it is constructed)
832 to prefix form (in which we can conveniently print or execute it). */
835 prefixify_expression (expr
)
836 register struct expression
*expr
;
839 sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expr
->nelts
);
840 register struct expression
*temp
;
841 register int inpos
= expr
->nelts
, outpos
= 0;
843 temp
= (struct expression
*) alloca (len
);
845 /* Copy the original expression into temp. */
846 memcpy (temp
, expr
, len
);
848 prefixify_subexp (temp
, expr
, inpos
, outpos
);
851 /* Return the number of exp_elements in the subexpression of EXPR
852 whose last exp_element is at index ENDPOS - 1 in EXPR. */
855 length_of_subexp (expr
, endpos
)
856 register struct expression
*expr
;
859 register int oplen
= 1;
860 register int args
= 0;
864 error ("?error in length_of_subexp");
866 i
= (int) expr
->elts
[endpos
- 1].opcode
;
872 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
873 oplen
= 5 + BYTES_TO_EXP_ELEM (oplen
+ 1);
896 case OP_F77_UNDETERMINED_ARGLIST
:
898 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
926 case STRUCTOP_STRUCT
:
934 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
935 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
939 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
940 oplen
= (oplen
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
941 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
);
946 args
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
947 args
-= longest_to_int (expr
->elts
[endpos
- 3].longconst
);
953 case TERNOP_SLICE_COUNT
:
958 case MULTI_SUBSCRIPT
:
960 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
963 case BINOP_ASSIGN_MODIFY
:
974 args
= 1 + (i
< (int) BINOP_END
);
979 oplen
+= length_of_subexp (expr
, endpos
- oplen
);
986 /* Copy the subexpression ending just before index INEND in INEXPR
987 into OUTEXPR, starting at index OUTBEG.
988 In the process, convert it from suffix to prefix form. */
991 prefixify_subexp (inexpr
, outexpr
, inend
, outbeg
)
992 register struct expression
*inexpr
;
993 struct expression
*outexpr
;
997 register int oplen
= 1;
998 register int args
= 0;
1001 enum exp_opcode opcode
;
1003 /* Compute how long the last operation is (in OPLEN),
1004 and also how many preceding subexpressions serve as
1005 arguments for it (in ARGS). */
1007 opcode
= inexpr
->elts
[inend
- 1].opcode
;
1012 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1013 oplen
= 5 + BYTES_TO_EXP_ELEM (oplen
+ 1);
1026 case OP_INTERNALVAR
:
1036 case OP_F77_UNDETERMINED_ARGLIST
:
1038 args
= 1 + longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1064 case STRUCTOP_STRUCT
:
1073 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1074 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
1078 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1079 oplen
= (oplen
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
1080 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
);
1085 args
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1086 args
-= longest_to_int (inexpr
->elts
[inend
- 3].longconst
);
1092 case TERNOP_SLICE_COUNT
:
1096 case BINOP_ASSIGN_MODIFY
:
1102 case MULTI_SUBSCRIPT
:
1104 args
= 1 + longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1113 args
= 1 + ((int) opcode
< (int) BINOP_END
);
1116 /* Copy the final operator itself, from the end of the input
1117 to the beginning of the output. */
1119 memcpy (&outexpr
->elts
[outbeg
], &inexpr
->elts
[inend
],
1120 EXP_ELEM_TO_BYTES (oplen
));
1123 /* Find the lengths of the arg subexpressions. */
1124 arglens
= (int *) alloca (args
* sizeof (int));
1125 for (i
= args
- 1; i
>= 0; i
--)
1127 oplen
= length_of_subexp (inexpr
, inend
);
1132 /* Now copy each subexpression, preserving the order of
1133 the subexpressions, but prefixifying each one.
1134 In this loop, inend starts at the beginning of
1135 the expression this level is working on
1136 and marches forward over the arguments.
1137 outbeg does similarly in the output. */
1138 for (i
= 0; i
< args
; i
++)
1142 prefixify_subexp (inexpr
, outexpr
, inend
, outbeg
);
1147 /* This page contains the two entry points to this file. */
1149 /* Read an expression from the string *STRINGPTR points to,
1150 parse it, and return a pointer to a struct expression that we malloc.
1151 Use block BLOCK as the lexical context for variable names;
1152 if BLOCK is zero, use the block of the selected stack frame.
1153 Meanwhile, advance *STRINGPTR to point after the expression,
1154 at the first nonwhite character that is not part of the expression
1155 (possibly a null character).
1157 If COMMA is nonzero, stop if a comma is reached. */
1160 parse_exp_1 (stringptr
, block
, comma
)
1162 struct block
*block
;
1165 struct cleanup
*old_chain
;
1167 lexptr
= *stringptr
;
1170 type_stack_depth
= 0;
1172 comma_terminates
= comma
;
1174 if (lexptr
== 0 || *lexptr
== 0)
1175 error_no_arg ("expression to compute");
1177 old_chain
= make_cleanup (free_funcalls
, 0 /*ignore*/);
1180 expression_context_block
= block
? block
: get_selected_block ();
1182 namecopy
= (char *) alloca (strlen (lexptr
) + 1);
1185 expout
= (struct expression
*)
1186 xmalloc (sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expout_size
));
1187 expout
->language_defn
= current_language
;
1188 make_cleanup (free_current_contents
, &expout
);
1190 if (current_language
->la_parser ())
1191 current_language
->la_error (NULL
);
1193 discard_cleanups (old_chain
);
1195 /* Record the actual number of expression elements, and then
1196 reallocate the expression memory so that we free up any
1199 expout
->nelts
= expout_ptr
;
1200 expout
= (struct expression
*)
1201 xrealloc ((char *) expout
,
1202 sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expout_ptr
));;
1204 /* Convert expression from postfix form as generated by yacc
1205 parser, to a prefix form. */
1207 if (expressiondebug
)
1208 dump_prefix_expression (expout
, gdb_stdlog
,
1209 "before conversion to prefix form");
1211 prefixify_expression (expout
);
1213 if (expressiondebug
)
1214 dump_postfix_expression (expout
, gdb_stdlog
,
1215 "after conversion to prefix form");
1217 *stringptr
= lexptr
;
1221 /* Parse STRING as an expression, and complain if this fails
1222 to use up all of the contents of STRING. */
1225 parse_expression (string
)
1228 register struct expression
*exp
;
1229 exp
= parse_exp_1 (&string
, 0, 0);
1231 error ("Junk after end of expression.");
1235 /* Stuff for maintaining a stack of types. Currently just used by C, but
1236 probably useful for any language which declares its types "backwards". */
1240 enum type_pieces tp
;
1242 if (type_stack_depth
== type_stack_size
)
1244 type_stack_size
*= 2;
1245 type_stack
= (union type_stack_elt
*)
1246 xrealloc ((char *) type_stack
, type_stack_size
* sizeof (*type_stack
));
1248 type_stack
[type_stack_depth
++].piece
= tp
;
1255 if (type_stack_depth
== type_stack_size
)
1257 type_stack_size
*= 2;
1258 type_stack
= (union type_stack_elt
*)
1259 xrealloc ((char *) type_stack
, type_stack_size
* sizeof (*type_stack
));
1261 type_stack
[type_stack_depth
++].int_val
= n
;
1267 if (type_stack_depth
)
1268 return type_stack
[--type_stack_depth
].piece
;
1275 if (type_stack_depth
)
1276 return type_stack
[--type_stack_depth
].int_val
;
1277 /* "Can't happen". */
1281 /* Pop the type stack and return the type which corresponds to FOLLOW_TYPE
1282 as modified by all the stuff on the stack. */
1284 follow_types (follow_type
)
1285 struct type
*follow_type
;
1289 struct type
*range_type
;
1292 switch (pop_type ())
1298 follow_type
= lookup_pointer_type (follow_type
);
1301 follow_type
= lookup_reference_type (follow_type
);
1304 array_size
= pop_type_int ();
1305 /* FIXME-type-allocation: need a way to free this type when we are
1308 create_range_type ((struct type
*) NULL
,
1309 builtin_type_int
, 0,
1310 array_size
>= 0 ? array_size
- 1 : 0);
1312 create_array_type ((struct type
*) NULL
,
1313 follow_type
, range_type
);
1315 TYPE_ARRAY_UPPER_BOUND_TYPE (follow_type
)
1316 = BOUND_CANNOT_BE_DETERMINED
;
1319 /* FIXME-type-allocation: need a way to free this type when we are
1321 follow_type
= lookup_function_type (follow_type
);
1327 static void build_parse (void);
1333 msym_text_symbol_type
=
1334 init_type (TYPE_CODE_FUNC
, 1, 0, "<text variable, no debug info>", NULL
);
1335 TYPE_TARGET_TYPE (msym_text_symbol_type
) = builtin_type_int
;
1336 msym_data_symbol_type
=
1337 init_type (TYPE_CODE_INT
, TARGET_INT_BIT
/ HOST_CHAR_BIT
, 0,
1338 "<data variable, no debug info>", NULL
);
1339 msym_unknown_symbol_type
=
1340 init_type (TYPE_CODE_INT
, 1, 0,
1341 "<variable (not text or data), no debug info>",
1344 /* create the std_regs table */
1363 /* create an empty table */
1364 std_regs
= xmalloc ((num_std_regs
+ 1) * sizeof *std_regs
);
1368 std_regs
[i
].name
= "pc";
1369 std_regs
[i
].regnum
= PC_REGNUM
;
1373 std_regs
[i
].name
= "fp";
1374 std_regs
[i
].regnum
= FP_REGNUM
;
1378 std_regs
[i
].name
= "sp";
1379 std_regs
[i
].regnum
= SP_REGNUM
;
1383 std_regs
[i
].name
= "ps";
1384 std_regs
[i
].regnum
= PS_REGNUM
;
1387 memset (&std_regs
[i
], 0, sizeof (std_regs
[i
]));
1391 _initialize_parse ()
1393 type_stack_size
= 80;
1394 type_stack_depth
= 0;
1395 type_stack
= (union type_stack_elt
*)
1396 xmalloc (type_stack_size
* sizeof (*type_stack
));
1400 /* FIXME - For the moment, handle types by swapping them in and out.
1401 Should be using the per-architecture data-pointer and a large
1403 register_gdbarch_swap (&msym_text_symbol_type
, sizeof (msym_text_symbol_type
), NULL
);
1404 register_gdbarch_swap (&msym_data_symbol_type
, sizeof (msym_data_symbol_type
), NULL
);
1405 register_gdbarch_swap (&msym_unknown_symbol_type
, sizeof (msym_unknown_symbol_type
), NULL
);
1407 register_gdbarch_swap (&num_std_regs
, sizeof (std_regs
), NULL
);
1408 register_gdbarch_swap (&std_regs
, sizeof (std_regs
), NULL
);
1409 register_gdbarch_swap (NULL
, 0, build_parse
);
1412 add_set_cmd ("expression", class_maintenance
, var_zinteger
,
1413 (char *) &expressiondebug
,
1414 "Set expression debugging.\n\
1415 When non-zero, the internal representation of expressions will be printed.",