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 */
47 /* Symbols which architectures can redefine. */
49 /* Some systems have routines whose names start with `$'. Giving this
50 macro a non-zero value tells GDB's expression parser to check for
51 such routines when parsing tokens that begin with `$'.
53 On HP-UX, certain system routines (millicode) have names beginning
54 with `$' or `$$'. For example, `$$dyncall' is a millicode routine
55 that handles inter-space procedure calls on PA-RISC. */
56 #ifndef SYMBOLS_CAN_START_WITH_DOLLAR
57 #define SYMBOLS_CAN_START_WITH_DOLLAR (0)
62 /* Global variables declared in parser-defs.h (and commented there). */
63 struct expression
*expout
;
66 struct block
*expression_context_block
;
67 struct block
*innermost_block
;
69 union type_stack_elt
*type_stack
;
70 int type_stack_depth
, type_stack_size
;
76 static int expressiondebug
= 0;
78 extern int hp_som_som_object_present
;
80 static void free_funcalls (void *ignore
);
83 prefixify_expression
PARAMS ((struct expression
*));
86 prefixify_subexp
PARAMS ((struct expression
*, struct expression
*, int, int));
88 void _initialize_parse
PARAMS ((void));
90 /* Data structure for saving values of arglist_len for function calls whose
91 arguments contain other function calls. */
99 static struct funcall
*funcall_chain
;
101 /* Assign machine-independent names to certain registers
102 (unless overridden by the REGISTER_NAMES table) */
104 unsigned num_std_regs
= 0;
105 struct std_regs
*std_regs
;
107 /* The generic method for targets to specify how their registers are
108 named. The mapping can be derived from three sources:
109 REGISTER_NAME; std_regs; or a target specific alias hook. */
112 target_map_name_to_register (str
, len
)
118 /* First try target specific aliases. We try these first because on some
119 systems standard names can be context dependent (eg. $pc on a
120 multiprocessor can be could be any of several PCs). */
121 #ifdef REGISTER_NAME_ALIAS_HOOK
122 i
= REGISTER_NAME_ALIAS_HOOK (str
, len
);
127 /* Search architectural register name space. */
128 for (i
= 0; i
< NUM_REGS
; i
++)
129 if (REGISTER_NAME (i
) && len
== strlen (REGISTER_NAME (i
))
130 && STREQN (str
, REGISTER_NAME (i
), len
))
135 /* Try standard aliases */
136 for (i
= 0; i
< num_std_regs
; i
++)
137 if (std_regs
[i
].name
&& len
== strlen (std_regs
[i
].name
)
138 && STREQN (str
, std_regs
[i
].name
, len
))
140 return std_regs
[i
].regnum
;
146 /* Begin counting arguments for a function call,
147 saving the data about any containing call. */
152 register struct funcall
*new;
154 new = (struct funcall
*) xmalloc (sizeof (struct funcall
));
155 new->next
= funcall_chain
;
156 new->arglist_len
= arglist_len
;
161 /* Return the number of arguments in a function call just terminated,
162 and restore the data for the containing function call. */
167 register int val
= arglist_len
;
168 register struct funcall
*call
= funcall_chain
;
169 funcall_chain
= call
->next
;
170 arglist_len
= call
->arglist_len
;
175 /* Free everything in the funcall chain.
176 Used when there is an error inside parsing. */
179 free_funcalls (void *ignore
)
181 register struct funcall
*call
, *next
;
183 for (call
= funcall_chain
; call
; call
= next
)
190 /* This page contains the functions for adding data to the struct expression
191 being constructed. */
193 /* Add one element to the end of the expression. */
195 /* To avoid a bug in the Sun 4 compiler, we pass things that can fit into
196 a register through here */
199 write_exp_elt (expelt
)
200 union exp_element expelt
;
202 if (expout_ptr
>= expout_size
)
205 expout
= (struct expression
*)
206 xrealloc ((char *) expout
, sizeof (struct expression
)
207 + EXP_ELEM_TO_BYTES (expout_size
));
209 expout
->elts
[expout_ptr
++] = expelt
;
213 write_exp_elt_opcode (expelt
)
214 enum exp_opcode expelt
;
216 union exp_element tmp
;
224 write_exp_elt_sym (expelt
)
225 struct symbol
*expelt
;
227 union exp_element tmp
;
235 write_exp_elt_block (b
)
238 union exp_element tmp
;
244 write_exp_elt_longcst (expelt
)
247 union exp_element tmp
;
249 tmp
.longconst
= expelt
;
255 write_exp_elt_dblcst (expelt
)
258 union exp_element tmp
;
260 tmp
.doubleconst
= expelt
;
266 write_exp_elt_type (expelt
)
269 union exp_element tmp
;
277 write_exp_elt_intern (expelt
)
278 struct internalvar
*expelt
;
280 union exp_element tmp
;
282 tmp
.internalvar
= expelt
;
287 /* Add a string constant to the end of the expression.
289 String constants are stored by first writing an expression element
290 that contains the length of the string, then stuffing the string
291 constant itself into however many expression elements are needed
292 to hold it, and then writing another expression element that contains
293 the length of the string. I.E. an expression element at each end of
294 the string records the string length, so you can skip over the
295 expression elements containing the actual string bytes from either
296 end of the string. Note that this also allows gdb to handle
297 strings with embedded null bytes, as is required for some languages.
299 Don't be fooled by the fact that the string is null byte terminated,
300 this is strictly for the convenience of debugging gdb itself. Gdb
301 Gdb does not depend up the string being null terminated, since the
302 actual length is recorded in expression elements at each end of the
303 string. The null byte is taken into consideration when computing how
304 many expression elements are required to hold the string constant, of
309 write_exp_string (str
)
312 register int len
= str
.length
;
314 register char *strdata
;
316 /* Compute the number of expression elements required to hold the string
317 (including a null byte terminator), along with one expression element
318 at each end to record the actual string length (not including the
319 null byte terminator). */
321 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
+ 1);
323 /* Ensure that we have enough available expression elements to store
326 if ((expout_ptr
+ lenelt
) >= expout_size
)
328 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
329 expout
= (struct expression
*)
330 xrealloc ((char *) expout
, (sizeof (struct expression
)
331 + EXP_ELEM_TO_BYTES (expout_size
)));
334 /* Write the leading length expression element (which advances the current
335 expression element index), then write the string constant followed by a
336 terminating null byte, and then write the trailing length expression
339 write_exp_elt_longcst ((LONGEST
) len
);
340 strdata
= (char *) &expout
->elts
[expout_ptr
];
341 memcpy (strdata
, str
.ptr
, len
);
342 *(strdata
+ len
) = '\0';
343 expout_ptr
+= lenelt
- 2;
344 write_exp_elt_longcst ((LONGEST
) len
);
347 /* Add a bitstring constant to the end of the expression.
349 Bitstring constants are stored by first writing an expression element
350 that contains the length of the bitstring (in bits), then stuffing the
351 bitstring constant itself into however many expression elements are
352 needed to hold it, and then writing another expression element that
353 contains the length of the bitstring. I.E. an expression element at
354 each end of the bitstring records the bitstring length, so you can skip
355 over the expression elements containing the actual bitstring bytes from
356 either end of the bitstring. */
359 write_exp_bitstring (str
)
362 register int bits
= str
.length
; /* length in bits */
363 register int len
= (bits
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
365 register char *strdata
;
367 /* Compute the number of expression elements required to hold the bitstring,
368 along with one expression element at each end to record the actual
369 bitstring length in bits. */
371 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
);
373 /* Ensure that we have enough available expression elements to store
376 if ((expout_ptr
+ lenelt
) >= expout_size
)
378 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
379 expout
= (struct expression
*)
380 xrealloc ((char *) expout
, (sizeof (struct expression
)
381 + EXP_ELEM_TO_BYTES (expout_size
)));
384 /* Write the leading length expression element (which advances the current
385 expression element index), then write the bitstring constant, and then
386 write the trailing length expression element. */
388 write_exp_elt_longcst ((LONGEST
) bits
);
389 strdata
= (char *) &expout
->elts
[expout_ptr
];
390 memcpy (strdata
, str
.ptr
, len
);
391 expout_ptr
+= lenelt
- 2;
392 write_exp_elt_longcst ((LONGEST
) bits
);
395 /* Add the appropriate elements for a minimal symbol to the end of
396 the expression. The rationale behind passing in text_symbol_type and
397 data_symbol_type was so that Modula-2 could pass in WORD for
398 data_symbol_type. Perhaps it still is useful to have those types vary
399 based on the language, but they no longer have names like "int", so
400 the initial rationale is gone. */
402 static struct type
*msym_text_symbol_type
;
403 static struct type
*msym_data_symbol_type
;
404 static struct type
*msym_unknown_symbol_type
;
407 write_exp_msymbol (msymbol
, text_symbol_type
, data_symbol_type
)
408 struct minimal_symbol
*msymbol
;
409 struct type
*text_symbol_type
;
410 struct type
*data_symbol_type
;
414 write_exp_elt_opcode (OP_LONG
);
415 write_exp_elt_type (lookup_pointer_type (builtin_type_void
));
417 addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
418 if (overlay_debugging
)
419 addr
= symbol_overlayed_address (addr
, SYMBOL_BFD_SECTION (msymbol
));
420 write_exp_elt_longcst ((LONGEST
) addr
);
422 write_exp_elt_opcode (OP_LONG
);
424 write_exp_elt_opcode (UNOP_MEMVAL
);
425 switch (msymbol
->type
)
429 case mst_solib_trampoline
:
430 write_exp_elt_type (msym_text_symbol_type
);
437 write_exp_elt_type (msym_data_symbol_type
);
441 write_exp_elt_type (msym_unknown_symbol_type
);
444 write_exp_elt_opcode (UNOP_MEMVAL
);
447 /* Recognize tokens that start with '$'. These include:
449 $regname A native register name or a "standard
452 $variable A convenience variable with a name chosen
455 $digits Value history with index <digits>, starting
456 from the first value which has index 1.
458 $$digits Value history with index <digits> relative
459 to the last value. I.E. $$0 is the last
460 value, $$1 is the one previous to that, $$2
461 is the one previous to $$1, etc.
463 $ | $0 | $$0 The last value in the value history.
465 $$ An abbreviation for the second to the last
466 value in the value history, I.E. $$1
471 write_dollar_variable (str
)
474 /* Handle the tokens $digits; also $ (short for $0) and $$ (short for $$1)
475 and $$digits (equivalent to $<-digits> if you could type that). */
479 /* Double dollar means negate the number and add -1 as well.
480 Thus $$ alone means -1. */
481 if (str
.length
>= 2 && str
.ptr
[1] == '$')
488 /* Just dollars (one or two) */
492 /* Is the rest of the token digits? */
493 for (; i
< str
.length
; i
++)
494 if (!(str
.ptr
[i
] >= '0' && str
.ptr
[i
] <= '9'))
498 i
= atoi (str
.ptr
+ 1 + negate
);
504 /* Handle tokens that refer to machine registers:
505 $ followed by a register name. */
506 i
= target_map_name_to_register (str
.ptr
+ 1, str
.length
- 1);
508 goto handle_register
;
510 if (SYMBOLS_CAN_START_WITH_DOLLAR
)
512 struct symbol
*sym
= NULL
;
513 struct minimal_symbol
*msym
= NULL
;
515 /* On HP-UX, certain system routines (millicode) have names beginning
516 with $ or $$, e.g. $$dyncall, which handles inter-space procedure
517 calls on PA-RISC. Check for those, first. */
519 /* This code is not enabled on non HP-UX systems, since worst case
520 symbol table lookup performance is awful, to put it mildly. */
522 sym
= lookup_symbol (copy_name (str
), (struct block
*) NULL
,
523 VAR_NAMESPACE
, (int *) NULL
, (struct symtab
**) NULL
);
526 write_exp_elt_opcode (OP_VAR_VALUE
);
527 write_exp_elt_block (block_found
); /* set by lookup_symbol */
528 write_exp_elt_sym (sym
);
529 write_exp_elt_opcode (OP_VAR_VALUE
);
532 msym
= lookup_minimal_symbol (copy_name (str
), NULL
, NULL
);
535 write_exp_msymbol (msym
,
536 lookup_function_type (builtin_type_int
),
542 /* Any other names starting in $ are debugger internal variables. */
544 write_exp_elt_opcode (OP_INTERNALVAR
);
545 write_exp_elt_intern (lookup_internalvar (copy_name (str
) + 1));
546 write_exp_elt_opcode (OP_INTERNALVAR
);
549 write_exp_elt_opcode (OP_LAST
);
550 write_exp_elt_longcst ((LONGEST
) i
);
551 write_exp_elt_opcode (OP_LAST
);
554 write_exp_elt_opcode (OP_REGISTER
);
555 write_exp_elt_longcst (i
);
556 write_exp_elt_opcode (OP_REGISTER
);
561 /* Parse a string that is possibly a namespace / nested class
562 specification, i.e., something of the form A::B::C::x. Input
563 (NAME) is the entire string; LEN is the current valid length; the
564 output is a string, TOKEN, which points to the largest recognized
565 prefix which is a series of namespaces or classes. CLASS_PREFIX is
566 another output, which records whether a nested class spec was
567 recognized (= 1) or a fully qualified variable name was found (=
568 0). ARGPTR is side-effected (if non-NULL) to point to beyond the
569 string recognized and consumed by this routine.
571 The return value is a pointer to the symbol for the base class or
572 variable if found, or NULL if not found. Callers must check this
573 first -- if NULL, the outputs may not be correct.
575 This function is used c-exp.y. This is used specifically to get
576 around HP aCC (and possibly other compilers), which insists on
577 generating names with embedded colons for namespace or nested class
580 (Argument LEN is currently unused. 1997-08-27)
582 Callers must free memory allocated for the output string TOKEN. */
584 static const char coloncolon
[2] =
588 parse_nested_classes_for_hpacc (name
, len
, token
, class_prefix
, argptr
)
595 /* Comment below comes from decode_line_1 which has very similar
596 code, which is called for "break" command parsing. */
598 /* We have what looks like a class or namespace
599 scope specification (A::B), possibly with many
600 levels of namespaces or classes (A::B::C::D).
602 Some versions of the HP ANSI C++ compiler (as also possibly
603 other compilers) generate class/function/member names with
604 embedded double-colons if they are inside namespaces. To
605 handle this, we loop a few times, considering larger and
606 larger prefixes of the string as though they were single
607 symbols. So, if the initially supplied string is
608 A::B::C::D::foo, we have to look up "A", then "A::B",
609 then "A::B::C", then "A::B::C::D", and finally
610 "A::B::C::D::foo" as single, monolithic symbols, because
611 A, B, C or D may be namespaces.
613 Note that namespaces can nest only inside other
614 namespaces, and not inside classes. So we need only
615 consider *prefixes* of the string; there is no need to look up
616 "B::C" separately as a symbol in the previous example. */
622 struct symbol
*sym_class
= NULL
;
623 struct symbol
*sym_var
= NULL
;
629 /* Check for HP-compiled executable -- in other cases
630 return NULL, and caller must default to standard GDB
633 if (!hp_som_som_object_present
)
634 return (struct symbol
*) NULL
;
638 /* Skip over whitespace and possible global "::" */
639 while (*p
&& (*p
== ' ' || *p
== '\t'))
641 if (p
[0] == ':' && p
[1] == ':')
643 while (*p
&& (*p
== ' ' || *p
== '\t'))
648 /* Get to the end of the next namespace or class spec. */
649 /* If we're looking at some non-token, fail immediately */
651 if (!(isalpha (*p
) || *p
== '$' || *p
== '_'))
652 return (struct symbol
*) NULL
;
654 while (*p
&& (isalnum (*p
) || *p
== '$' || *p
== '_'))
659 /* If we have the start of a template specification,
660 scan right ahead to its end */
661 q
= find_template_name_end (p
);
668 /* Skip over "::" and whitespace for next time around */
669 while (*p
&& (*p
== ' ' || *p
== '\t'))
671 if (p
[0] == ':' && p
[1] == ':')
673 while (*p
&& (*p
== ' ' || *p
== '\t'))
676 /* Done with tokens? */
677 if (!*p
|| !(isalpha (*p
) || *p
== '$' || *p
== '_'))
680 tmp
= (char *) alloca (prefix_len
+ end
- start
+ 3);
683 memcpy (tmp
, prefix
, prefix_len
);
684 memcpy (tmp
+ prefix_len
, coloncolon
, 2);
685 memcpy (tmp
+ prefix_len
+ 2, start
, end
- start
);
686 tmp
[prefix_len
+ 2 + end
- start
] = '\000';
690 memcpy (tmp
, start
, end
- start
);
691 tmp
[end
- start
] = '\000';
695 prefix_len
= strlen (prefix
);
697 /* See if the prefix we have now is something we know about */
701 /* More tokens to process, so this must be a class/namespace */
702 sym_class
= lookup_symbol (prefix
, 0, STRUCT_NAMESPACE
,
703 0, (struct symtab
**) NULL
);
707 /* No more tokens, so try as a variable first */
708 sym_var
= lookup_symbol (prefix
, 0, VAR_NAMESPACE
,
709 0, (struct symtab
**) NULL
);
710 /* If failed, try as class/namespace */
712 sym_class
= lookup_symbol (prefix
, 0, STRUCT_NAMESPACE
,
713 0, (struct symtab
**) NULL
);
718 (t
= check_typedef (SYMBOL_TYPE (sym_class
)),
719 (TYPE_CODE (t
) == TYPE_CODE_STRUCT
720 || TYPE_CODE (t
) == TYPE_CODE_UNION
))))
722 /* We found a valid token */
723 *token
= (char *) xmalloc (prefix_len
+ 1);
724 memcpy (*token
, prefix
, prefix_len
);
725 (*token
)[prefix_len
] = '\000';
729 /* No variable or class/namespace found, no more tokens */
731 return (struct symbol
*) NULL
;
734 /* Out of loop, so we must have found a valid token */
741 *argptr
= done
? p
: end
;
743 return sym_var
? sym_var
: sym_class
; /* found */
747 find_template_name_end (p
)
751 int just_seen_right
= 0;
752 int just_seen_colon
= 0;
753 int just_seen_space
= 0;
755 if (!p
|| (*p
!= '<'))
766 /* In future, may want to allow these?? */
769 depth
++; /* start nested template */
770 if (just_seen_colon
|| just_seen_right
|| just_seen_space
)
771 return 0; /* but not after : or :: or > or space */
774 if (just_seen_colon
|| just_seen_right
)
775 return 0; /* end a (nested?) template */
776 just_seen_right
= 1; /* but not after : or :: */
777 if (--depth
== 0) /* also disallow >>, insist on > > */
778 return ++p
; /* if outermost ended, return */
781 if (just_seen_space
|| (just_seen_colon
> 1))
782 return 0; /* nested class spec coming up */
783 just_seen_colon
++; /* we allow :: but not :::: */
788 if (!((*p
>= 'a' && *p
<= 'z') || /* allow token chars */
789 (*p
>= 'A' && *p
<= 'Z') ||
790 (*p
>= '0' && *p
<= '9') ||
791 (*p
== '_') || (*p
== ',') || /* commas for template args */
792 (*p
== '&') || (*p
== '*') || /* pointer and ref types */
793 (*p
== '(') || (*p
== ')') || /* function types */
794 (*p
== '[') || (*p
== ']'))) /* array types */
809 /* Return a null-terminated temporary copy of the name
810 of a string token. */
816 memcpy (namecopy
, token
.ptr
, token
.length
);
817 namecopy
[token
.length
] = 0;
821 /* Reverse an expression from suffix form (in which it is constructed)
822 to prefix form (in which we can conveniently print or execute it). */
825 prefixify_expression (expr
)
826 register struct expression
*expr
;
829 sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expr
->nelts
);
830 register struct expression
*temp
;
831 register int inpos
= expr
->nelts
, outpos
= 0;
833 temp
= (struct expression
*) alloca (len
);
835 /* Copy the original expression into temp. */
836 memcpy (temp
, expr
, len
);
838 prefixify_subexp (temp
, expr
, inpos
, outpos
);
841 /* Return the number of exp_elements in the subexpression of EXPR
842 whose last exp_element is at index ENDPOS - 1 in EXPR. */
845 length_of_subexp (expr
, endpos
)
846 register struct expression
*expr
;
849 register int oplen
= 1;
850 register int args
= 0;
854 error ("?error in length_of_subexp");
856 i
= (int) expr
->elts
[endpos
- 1].opcode
;
862 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
863 oplen
= 5 + BYTES_TO_EXP_ELEM (oplen
+ 1);
886 case OP_F77_UNDETERMINED_ARGLIST
:
888 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
916 case STRUCTOP_STRUCT
:
924 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
925 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
929 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
930 oplen
= (oplen
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
931 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
);
936 args
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
937 args
-= longest_to_int (expr
->elts
[endpos
- 3].longconst
);
943 case TERNOP_SLICE_COUNT
:
948 case MULTI_SUBSCRIPT
:
950 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
953 case BINOP_ASSIGN_MODIFY
:
964 args
= 1 + (i
< (int) BINOP_END
);
969 oplen
+= length_of_subexp (expr
, endpos
- oplen
);
976 /* Copy the subexpression ending just before index INEND in INEXPR
977 into OUTEXPR, starting at index OUTBEG.
978 In the process, convert it from suffix to prefix form. */
981 prefixify_subexp (inexpr
, outexpr
, inend
, outbeg
)
982 register struct expression
*inexpr
;
983 struct expression
*outexpr
;
987 register int oplen
= 1;
988 register int args
= 0;
991 enum exp_opcode opcode
;
993 /* Compute how long the last operation is (in OPLEN),
994 and also how many preceding subexpressions serve as
995 arguments for it (in ARGS). */
997 opcode
= inexpr
->elts
[inend
- 1].opcode
;
1002 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1003 oplen
= 5 + BYTES_TO_EXP_ELEM (oplen
+ 1);
1016 case OP_INTERNALVAR
:
1026 case OP_F77_UNDETERMINED_ARGLIST
:
1028 args
= 1 + longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1054 case STRUCTOP_STRUCT
:
1063 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1064 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
1068 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1069 oplen
= (oplen
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
1070 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
);
1075 args
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1076 args
-= longest_to_int (inexpr
->elts
[inend
- 3].longconst
);
1082 case TERNOP_SLICE_COUNT
:
1086 case BINOP_ASSIGN_MODIFY
:
1092 case MULTI_SUBSCRIPT
:
1094 args
= 1 + longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1103 args
= 1 + ((int) opcode
< (int) BINOP_END
);
1106 /* Copy the final operator itself, from the end of the input
1107 to the beginning of the output. */
1109 memcpy (&outexpr
->elts
[outbeg
], &inexpr
->elts
[inend
],
1110 EXP_ELEM_TO_BYTES (oplen
));
1113 /* Find the lengths of the arg subexpressions. */
1114 arglens
= (int *) alloca (args
* sizeof (int));
1115 for (i
= args
- 1; i
>= 0; i
--)
1117 oplen
= length_of_subexp (inexpr
, inend
);
1122 /* Now copy each subexpression, preserving the order of
1123 the subexpressions, but prefixifying each one.
1124 In this loop, inend starts at the beginning of
1125 the expression this level is working on
1126 and marches forward over the arguments.
1127 outbeg does similarly in the output. */
1128 for (i
= 0; i
< args
; i
++)
1132 prefixify_subexp (inexpr
, outexpr
, inend
, outbeg
);
1137 /* This page contains the two entry points to this file. */
1139 /* Read an expression from the string *STRINGPTR points to,
1140 parse it, and return a pointer to a struct expression that we malloc.
1141 Use block BLOCK as the lexical context for variable names;
1142 if BLOCK is zero, use the block of the selected stack frame.
1143 Meanwhile, advance *STRINGPTR to point after the expression,
1144 at the first nonwhite character that is not part of the expression
1145 (possibly a null character).
1147 If COMMA is nonzero, stop if a comma is reached. */
1150 parse_exp_1 (stringptr
, block
, comma
)
1152 struct block
*block
;
1155 struct cleanup
*old_chain
;
1157 lexptr
= *stringptr
;
1160 type_stack_depth
= 0;
1162 comma_terminates
= comma
;
1164 if (lexptr
== 0 || *lexptr
== 0)
1165 error_no_arg ("expression to compute");
1167 old_chain
= make_cleanup (free_funcalls
, 0 /*ignore*/);
1170 expression_context_block
= block
? block
: get_selected_block ();
1172 namecopy
= (char *) alloca (strlen (lexptr
) + 1);
1175 expout
= (struct expression
*)
1176 xmalloc (sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expout_size
));
1177 expout
->language_defn
= current_language
;
1178 make_cleanup (free_current_contents
, &expout
);
1180 if (current_language
->la_parser ())
1181 current_language
->la_error (NULL
);
1183 discard_cleanups (old_chain
);
1185 /* Record the actual number of expression elements, and then
1186 reallocate the expression memory so that we free up any
1189 expout
->nelts
= expout_ptr
;
1190 expout
= (struct expression
*)
1191 xrealloc ((char *) expout
,
1192 sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expout_ptr
));;
1194 /* Convert expression from postfix form as generated by yacc
1195 parser, to a prefix form. */
1197 if (expressiondebug
)
1198 dump_prefix_expression (expout
, gdb_stdlog
,
1199 "before conversion to prefix form");
1201 prefixify_expression (expout
);
1203 if (expressiondebug
)
1204 dump_postfix_expression (expout
, gdb_stdlog
,
1205 "after conversion to prefix form");
1207 *stringptr
= lexptr
;
1211 /* Parse STRING as an expression, and complain if this fails
1212 to use up all of the contents of STRING. */
1215 parse_expression (string
)
1218 register struct expression
*exp
;
1219 exp
= parse_exp_1 (&string
, 0, 0);
1221 error ("Junk after end of expression.");
1225 /* Stuff for maintaining a stack of types. Currently just used by C, but
1226 probably useful for any language which declares its types "backwards". */
1230 enum type_pieces tp
;
1232 if (type_stack_depth
== type_stack_size
)
1234 type_stack_size
*= 2;
1235 type_stack
= (union type_stack_elt
*)
1236 xrealloc ((char *) type_stack
, type_stack_size
* sizeof (*type_stack
));
1238 type_stack
[type_stack_depth
++].piece
= tp
;
1245 if (type_stack_depth
== type_stack_size
)
1247 type_stack_size
*= 2;
1248 type_stack
= (union type_stack_elt
*)
1249 xrealloc ((char *) type_stack
, type_stack_size
* sizeof (*type_stack
));
1251 type_stack
[type_stack_depth
++].int_val
= n
;
1257 if (type_stack_depth
)
1258 return type_stack
[--type_stack_depth
].piece
;
1265 if (type_stack_depth
)
1266 return type_stack
[--type_stack_depth
].int_val
;
1267 /* "Can't happen". */
1271 /* Pop the type stack and return the type which corresponds to FOLLOW_TYPE
1272 as modified by all the stuff on the stack. */
1274 follow_types (follow_type
)
1275 struct type
*follow_type
;
1279 struct type
*range_type
;
1282 switch (pop_type ())
1288 follow_type
= lookup_pointer_type (follow_type
);
1291 follow_type
= lookup_reference_type (follow_type
);
1294 array_size
= pop_type_int ();
1295 /* FIXME-type-allocation: need a way to free this type when we are
1298 create_range_type ((struct type
*) NULL
,
1299 builtin_type_int
, 0,
1300 array_size
>= 0 ? array_size
- 1 : 0);
1302 create_array_type ((struct type
*) NULL
,
1303 follow_type
, range_type
);
1305 TYPE_ARRAY_UPPER_BOUND_TYPE (follow_type
)
1306 = BOUND_CANNOT_BE_DETERMINED
;
1309 /* FIXME-type-allocation: need a way to free this type when we are
1311 follow_type
= lookup_function_type (follow_type
);
1317 static void build_parse
PARAMS ((void));
1323 msym_text_symbol_type
=
1324 init_type (TYPE_CODE_FUNC
, 1, 0, "<text variable, no debug info>", NULL
);
1325 TYPE_TARGET_TYPE (msym_text_symbol_type
) = builtin_type_int
;
1326 msym_data_symbol_type
=
1327 init_type (TYPE_CODE_INT
, TARGET_INT_BIT
/ HOST_CHAR_BIT
, 0,
1328 "<data variable, no debug info>", NULL
);
1329 msym_unknown_symbol_type
=
1330 init_type (TYPE_CODE_INT
, 1, 0,
1331 "<variable (not text or data), no debug info>",
1334 /* create the std_regs table */
1353 /* create an empty table */
1354 std_regs
= xmalloc ((num_std_regs
+ 1) * sizeof *std_regs
);
1358 std_regs
[i
].name
= "pc";
1359 std_regs
[i
].regnum
= PC_REGNUM
;
1363 std_regs
[i
].name
= "fp";
1364 std_regs
[i
].regnum
= FP_REGNUM
;
1368 std_regs
[i
].name
= "sp";
1369 std_regs
[i
].regnum
= SP_REGNUM
;
1373 std_regs
[i
].name
= "ps";
1374 std_regs
[i
].regnum
= PS_REGNUM
;
1377 memset (&std_regs
[i
], 0, sizeof (std_regs
[i
]));
1381 _initialize_parse ()
1383 type_stack_size
= 80;
1384 type_stack_depth
= 0;
1385 type_stack
= (union type_stack_elt
*)
1386 xmalloc (type_stack_size
* sizeof (*type_stack
));
1390 /* FIXME - For the moment, handle types by swapping them in and out.
1391 Should be using the per-architecture data-pointer and a large
1393 register_gdbarch_swap (&msym_text_symbol_type
, sizeof (msym_text_symbol_type
), NULL
);
1394 register_gdbarch_swap (&msym_data_symbol_type
, sizeof (msym_data_symbol_type
), NULL
);
1395 register_gdbarch_swap (&msym_unknown_symbol_type
, sizeof (msym_unknown_symbol_type
), NULL
);
1397 register_gdbarch_swap (&num_std_regs
, sizeof (std_regs
), NULL
);
1398 register_gdbarch_swap (&std_regs
, sizeof (std_regs
), NULL
);
1399 register_gdbarch_swap (NULL
, 0, build_parse
);
1402 add_set_cmd ("expression", class_maintenance
, var_zinteger
,
1403 (char *) &expressiondebug
,
1404 "Set expression debugging.\n\
1405 When non-zero, the internal representation of expressions will be printed.",