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
;
81 free_funcalls
PARAMS ((void));
84 prefixify_expression
PARAMS ((struct expression
*));
87 prefixify_subexp
PARAMS ((struct expression
*, struct expression
*, int, int));
89 void _initialize_parse
PARAMS ((void));
91 /* Data structure for saving values of arglist_len for function calls whose
92 arguments contain other function calls. */
100 static struct funcall
*funcall_chain
;
102 /* Assign machine-independent names to certain registers
103 (unless overridden by the REGISTER_NAMES table) */
105 unsigned num_std_regs
= 0;
106 struct std_regs
*std_regs
;
108 /* The generic method for targets to specify how their registers are
109 named. The mapping can be derived from three sources:
110 REGISTER_NAME; std_regs; or a target specific alias hook. */
113 target_map_name_to_register (str
, len
)
119 /* First try target specific aliases. We try these first because on some
120 systems standard names can be context dependent (eg. $pc on a
121 multiprocessor can be could be any of several PCs). */
122 #ifdef REGISTER_NAME_ALIAS_HOOK
123 i
= REGISTER_NAME_ALIAS_HOOK (str
, len
);
128 /* Search architectural register name space. */
129 for (i
= 0; i
< NUM_REGS
; i
++)
130 if (REGISTER_NAME (i
) && len
== strlen (REGISTER_NAME (i
))
131 && STREQN (str
, REGISTER_NAME (i
), len
))
136 /* Try standard aliases */
137 for (i
= 0; i
< num_std_regs
; i
++)
138 if (std_regs
[i
].name
&& len
== strlen (std_regs
[i
].name
)
139 && STREQN (str
, std_regs
[i
].name
, len
))
141 return std_regs
[i
].regnum
;
147 /* Begin counting arguments for a function call,
148 saving the data about any containing call. */
153 register struct funcall
*new;
155 new = (struct funcall
*) xmalloc (sizeof (struct funcall
));
156 new->next
= funcall_chain
;
157 new->arglist_len
= arglist_len
;
162 /* Return the number of arguments in a function call just terminated,
163 and restore the data for the containing function call. */
168 register int val
= arglist_len
;
169 register struct funcall
*call
= funcall_chain
;
170 funcall_chain
= call
->next
;
171 arglist_len
= call
->arglist_len
;
176 /* Free everything in the funcall chain.
177 Used when there is an error inside parsing. */
182 register struct funcall
*call
, *next
;
184 for (call
= funcall_chain
; call
; call
= next
)
191 /* This page contains the functions for adding data to the struct expression
192 being constructed. */
194 /* Add one element to the end of the expression. */
196 /* To avoid a bug in the Sun 4 compiler, we pass things that can fit into
197 a register through here */
200 write_exp_elt (expelt
)
201 union exp_element expelt
;
203 if (expout_ptr
>= expout_size
)
206 expout
= (struct expression
*)
207 xrealloc ((char *) expout
, sizeof (struct expression
)
208 + EXP_ELEM_TO_BYTES (expout_size
));
210 expout
->elts
[expout_ptr
++] = expelt
;
214 write_exp_elt_opcode (expelt
)
215 enum exp_opcode expelt
;
217 union exp_element tmp
;
225 write_exp_elt_sym (expelt
)
226 struct symbol
*expelt
;
228 union exp_element tmp
;
236 write_exp_elt_block (b
)
239 union exp_element tmp
;
245 write_exp_elt_longcst (expelt
)
248 union exp_element tmp
;
250 tmp
.longconst
= expelt
;
256 write_exp_elt_dblcst (expelt
)
259 union exp_element tmp
;
261 tmp
.doubleconst
= expelt
;
267 write_exp_elt_type (expelt
)
270 union exp_element tmp
;
278 write_exp_elt_intern (expelt
)
279 struct internalvar
*expelt
;
281 union exp_element tmp
;
283 tmp
.internalvar
= expelt
;
288 /* Add a string constant to the end of the expression.
290 String constants are stored by first writing an expression element
291 that contains the length of the string, then stuffing the string
292 constant itself into however many expression elements are needed
293 to hold it, and then writing another expression element that contains
294 the length of the string. I.E. an expression element at each end of
295 the string records the string length, so you can skip over the
296 expression elements containing the actual string bytes from either
297 end of the string. Note that this also allows gdb to handle
298 strings with embedded null bytes, as is required for some languages.
300 Don't be fooled by the fact that the string is null byte terminated,
301 this is strictly for the convenience of debugging gdb itself. Gdb
302 Gdb does not depend up the string being null terminated, since the
303 actual length is recorded in expression elements at each end of the
304 string. The null byte is taken into consideration when computing how
305 many expression elements are required to hold the string constant, of
310 write_exp_string (str
)
313 register int len
= str
.length
;
315 register char *strdata
;
317 /* Compute the number of expression elements required to hold the string
318 (including a null byte terminator), along with one expression element
319 at each end to record the actual string length (not including the
320 null byte terminator). */
322 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
+ 1);
324 /* Ensure that we have enough available expression elements to store
327 if ((expout_ptr
+ lenelt
) >= expout_size
)
329 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
330 expout
= (struct expression
*)
331 xrealloc ((char *) expout
, (sizeof (struct expression
)
332 + EXP_ELEM_TO_BYTES (expout_size
)));
335 /* Write the leading length expression element (which advances the current
336 expression element index), then write the string constant followed by a
337 terminating null byte, and then write the trailing length expression
340 write_exp_elt_longcst ((LONGEST
) len
);
341 strdata
= (char *) &expout
->elts
[expout_ptr
];
342 memcpy (strdata
, str
.ptr
, len
);
343 *(strdata
+ len
) = '\0';
344 expout_ptr
+= lenelt
- 2;
345 write_exp_elt_longcst ((LONGEST
) len
);
348 /* Add a bitstring constant to the end of the expression.
350 Bitstring constants are stored by first writing an expression element
351 that contains the length of the bitstring (in bits), then stuffing the
352 bitstring constant itself into however many expression elements are
353 needed to hold it, and then writing another expression element that
354 contains the length of the bitstring. I.E. an expression element at
355 each end of the bitstring records the bitstring length, so you can skip
356 over the expression elements containing the actual bitstring bytes from
357 either end of the bitstring. */
360 write_exp_bitstring (str
)
363 register int bits
= str
.length
; /* length in bits */
364 register int len
= (bits
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
366 register char *strdata
;
368 /* Compute the number of expression elements required to hold the bitstring,
369 along with one expression element at each end to record the actual
370 bitstring length in bits. */
372 lenelt
= 2 + BYTES_TO_EXP_ELEM (len
);
374 /* Ensure that we have enough available expression elements to store
377 if ((expout_ptr
+ lenelt
) >= expout_size
)
379 expout_size
= max (expout_size
* 2, expout_ptr
+ lenelt
+ 10);
380 expout
= (struct expression
*)
381 xrealloc ((char *) expout
, (sizeof (struct expression
)
382 + EXP_ELEM_TO_BYTES (expout_size
)));
385 /* Write the leading length expression element (which advances the current
386 expression element index), then write the bitstring constant, and then
387 write the trailing length expression element. */
389 write_exp_elt_longcst ((LONGEST
) bits
);
390 strdata
= (char *) &expout
->elts
[expout_ptr
];
391 memcpy (strdata
, str
.ptr
, len
);
392 expout_ptr
+= lenelt
- 2;
393 write_exp_elt_longcst ((LONGEST
) bits
);
396 /* Add the appropriate elements for a minimal symbol to the end of
397 the expression. The rationale behind passing in text_symbol_type and
398 data_symbol_type was so that Modula-2 could pass in WORD for
399 data_symbol_type. Perhaps it still is useful to have those types vary
400 based on the language, but they no longer have names like "int", so
401 the initial rationale is gone. */
403 static struct type
*msym_text_symbol_type
;
404 static struct type
*msym_data_symbol_type
;
405 static struct type
*msym_unknown_symbol_type
;
408 write_exp_msymbol (msymbol
, text_symbol_type
, data_symbol_type
)
409 struct minimal_symbol
*msymbol
;
410 struct type
*text_symbol_type
;
411 struct type
*data_symbol_type
;
415 write_exp_elt_opcode (OP_LONG
);
416 write_exp_elt_type (lookup_pointer_type (builtin_type_void
));
418 addr
= SYMBOL_VALUE_ADDRESS (msymbol
);
419 if (overlay_debugging
)
420 addr
= symbol_overlayed_address (addr
, SYMBOL_BFD_SECTION (msymbol
));
421 write_exp_elt_longcst ((LONGEST
) addr
);
423 write_exp_elt_opcode (OP_LONG
);
425 write_exp_elt_opcode (UNOP_MEMVAL
);
426 switch (msymbol
->type
)
430 case mst_solib_trampoline
:
431 write_exp_elt_type (msym_text_symbol_type
);
438 write_exp_elt_type (msym_data_symbol_type
);
442 write_exp_elt_type (msym_unknown_symbol_type
);
445 write_exp_elt_opcode (UNOP_MEMVAL
);
448 /* Recognize tokens that start with '$'. These include:
450 $regname A native register name or a "standard
453 $variable A convenience variable with a name chosen
456 $digits Value history with index <digits>, starting
457 from the first value which has index 1.
459 $$digits Value history with index <digits> relative
460 to the last value. I.E. $$0 is the last
461 value, $$1 is the one previous to that, $$2
462 is the one previous to $$1, etc.
464 $ | $0 | $$0 The last value in the value history.
466 $$ An abbreviation for the second to the last
467 value in the value history, I.E. $$1
472 write_dollar_variable (str
)
475 /* Handle the tokens $digits; also $ (short for $0) and $$ (short for $$1)
476 and $$digits (equivalent to $<-digits> if you could type that). */
480 /* Double dollar means negate the number and add -1 as well.
481 Thus $$ alone means -1. */
482 if (str
.length
>= 2 && str
.ptr
[1] == '$')
489 /* Just dollars (one or two) */
493 /* Is the rest of the token digits? */
494 for (; i
< str
.length
; i
++)
495 if (!(str
.ptr
[i
] >= '0' && str
.ptr
[i
] <= '9'))
499 i
= atoi (str
.ptr
+ 1 + negate
);
505 /* Handle tokens that refer to machine registers:
506 $ followed by a register name. */
507 i
= target_map_name_to_register (str
.ptr
+ 1, str
.length
- 1);
509 goto handle_register
;
511 if (SYMBOLS_CAN_START_WITH_DOLLAR
)
513 struct symbol
*sym
= NULL
;
514 struct minimal_symbol
*msym
= NULL
;
516 /* On HP-UX, certain system routines (millicode) have names beginning
517 with $ or $$, e.g. $$dyncall, which handles inter-space procedure
518 calls on PA-RISC. Check for those, first. */
520 /* This code is not enabled on non HP-UX systems, since worst case
521 symbol table lookup performance is awful, to put it mildly. */
523 sym
= lookup_symbol (copy_name (str
), (struct block
*) NULL
,
524 VAR_NAMESPACE
, (int *) NULL
, (struct symtab
**) NULL
);
527 write_exp_elt_opcode (OP_VAR_VALUE
);
528 write_exp_elt_block (block_found
); /* set by lookup_symbol */
529 write_exp_elt_sym (sym
);
530 write_exp_elt_opcode (OP_VAR_VALUE
);
533 msym
= lookup_minimal_symbol (copy_name (str
), NULL
, NULL
);
536 write_exp_msymbol (msym
,
537 lookup_function_type (builtin_type_int
),
543 /* Any other names starting in $ are debugger internal variables. */
545 write_exp_elt_opcode (OP_INTERNALVAR
);
546 write_exp_elt_intern (lookup_internalvar (copy_name (str
) + 1));
547 write_exp_elt_opcode (OP_INTERNALVAR
);
550 write_exp_elt_opcode (OP_LAST
);
551 write_exp_elt_longcst ((LONGEST
) i
);
552 write_exp_elt_opcode (OP_LAST
);
555 write_exp_elt_opcode (OP_REGISTER
);
556 write_exp_elt_longcst (i
);
557 write_exp_elt_opcode (OP_REGISTER
);
562 /* Parse a string that is possibly a namespace / nested class
563 specification, i.e., something of the form A::B::C::x. Input
564 (NAME) is the entire string; LEN is the current valid length; the
565 output is a string, TOKEN, which points to the largest recognized
566 prefix which is a series of namespaces or classes. CLASS_PREFIX is
567 another output, which records whether a nested class spec was
568 recognized (= 1) or a fully qualified variable name was found (=
569 0). ARGPTR is side-effected (if non-NULL) to point to beyond the
570 string recognized and consumed by this routine.
572 The return value is a pointer to the symbol for the base class or
573 variable if found, or NULL if not found. Callers must check this
574 first -- if NULL, the outputs may not be correct.
576 This function is used c-exp.y. This is used specifically to get
577 around HP aCC (and possibly other compilers), which insists on
578 generating names with embedded colons for namespace or nested class
581 (Argument LEN is currently unused. 1997-08-27)
583 Callers must free memory allocated for the output string TOKEN. */
585 static const char coloncolon
[2] =
589 parse_nested_classes_for_hpacc (name
, len
, token
, class_prefix
, argptr
)
596 /* Comment below comes from decode_line_1 which has very similar
597 code, which is called for "break" command parsing. */
599 /* We have what looks like a class or namespace
600 scope specification (A::B), possibly with many
601 levels of namespaces or classes (A::B::C::D).
603 Some versions of the HP ANSI C++ compiler (as also possibly
604 other compilers) generate class/function/member names with
605 embedded double-colons if they are inside namespaces. To
606 handle this, we loop a few times, considering larger and
607 larger prefixes of the string as though they were single
608 symbols. So, if the initially supplied string is
609 A::B::C::D::foo, we have to look up "A", then "A::B",
610 then "A::B::C", then "A::B::C::D", and finally
611 "A::B::C::D::foo" as single, monolithic symbols, because
612 A, B, C or D may be namespaces.
614 Note that namespaces can nest only inside other
615 namespaces, and not inside classes. So we need only
616 consider *prefixes* of the string; there is no need to look up
617 "B::C" separately as a symbol in the previous example. */
623 struct symbol
*sym_class
= NULL
;
624 struct symbol
*sym_var
= NULL
;
630 /* Check for HP-compiled executable -- in other cases
631 return NULL, and caller must default to standard GDB
634 if (!hp_som_som_object_present
)
635 return (struct symbol
*) NULL
;
639 /* Skip over whitespace and possible global "::" */
640 while (*p
&& (*p
== ' ' || *p
== '\t'))
642 if (p
[0] == ':' && p
[1] == ':')
644 while (*p
&& (*p
== ' ' || *p
== '\t'))
649 /* Get to the end of the next namespace or class spec. */
650 /* If we're looking at some non-token, fail immediately */
652 if (!(isalpha (*p
) || *p
== '$' || *p
== '_'))
653 return (struct symbol
*) NULL
;
655 while (*p
&& (isalnum (*p
) || *p
== '$' || *p
== '_'))
660 /* If we have the start of a template specification,
661 scan right ahead to its end */
662 q
= find_template_name_end (p
);
669 /* Skip over "::" and whitespace for next time around */
670 while (*p
&& (*p
== ' ' || *p
== '\t'))
672 if (p
[0] == ':' && p
[1] == ':')
674 while (*p
&& (*p
== ' ' || *p
== '\t'))
677 /* Done with tokens? */
678 if (!*p
|| !(isalpha (*p
) || *p
== '$' || *p
== '_'))
681 tmp
= (char *) alloca (prefix_len
+ end
- start
+ 3);
684 memcpy (tmp
, prefix
, prefix_len
);
685 memcpy (tmp
+ prefix_len
, coloncolon
, 2);
686 memcpy (tmp
+ prefix_len
+ 2, start
, end
- start
);
687 tmp
[prefix_len
+ 2 + end
- start
] = '\000';
691 memcpy (tmp
, start
, end
- start
);
692 tmp
[end
- start
] = '\000';
696 prefix_len
= strlen (prefix
);
698 /* See if the prefix we have now is something we know about */
702 /* More tokens to process, so this must be a class/namespace */
703 sym_class
= lookup_symbol (prefix
, 0, STRUCT_NAMESPACE
,
704 0, (struct symtab
**) NULL
);
708 /* No more tokens, so try as a variable first */
709 sym_var
= lookup_symbol (prefix
, 0, VAR_NAMESPACE
,
710 0, (struct symtab
**) NULL
);
711 /* If failed, try as class/namespace */
713 sym_class
= lookup_symbol (prefix
, 0, STRUCT_NAMESPACE
,
714 0, (struct symtab
**) NULL
);
719 (t
= check_typedef (SYMBOL_TYPE (sym_class
)),
720 (TYPE_CODE (t
) == TYPE_CODE_STRUCT
721 || TYPE_CODE (t
) == TYPE_CODE_UNION
))))
723 /* We found a valid token */
724 *token
= (char *) xmalloc (prefix_len
+ 1);
725 memcpy (*token
, prefix
, prefix_len
);
726 (*token
)[prefix_len
] = '\000';
730 /* No variable or class/namespace found, no more tokens */
732 return (struct symbol
*) NULL
;
735 /* Out of loop, so we must have found a valid token */
742 *argptr
= done
? p
: end
;
744 return sym_var
? sym_var
: sym_class
; /* found */
748 find_template_name_end (p
)
752 int just_seen_right
= 0;
753 int just_seen_colon
= 0;
754 int just_seen_space
= 0;
756 if (!p
|| (*p
!= '<'))
767 /* In future, may want to allow these?? */
770 depth
++; /* start nested template */
771 if (just_seen_colon
|| just_seen_right
|| just_seen_space
)
772 return 0; /* but not after : or :: or > or space */
775 if (just_seen_colon
|| just_seen_right
)
776 return 0; /* end a (nested?) template */
777 just_seen_right
= 1; /* but not after : or :: */
778 if (--depth
== 0) /* also disallow >>, insist on > > */
779 return ++p
; /* if outermost ended, return */
782 if (just_seen_space
|| (just_seen_colon
> 1))
783 return 0; /* nested class spec coming up */
784 just_seen_colon
++; /* we allow :: but not :::: */
789 if (!((*p
>= 'a' && *p
<= 'z') || /* allow token chars */
790 (*p
>= 'A' && *p
<= 'Z') ||
791 (*p
>= '0' && *p
<= '9') ||
792 (*p
== '_') || (*p
== ',') || /* commas for template args */
793 (*p
== '&') || (*p
== '*') || /* pointer and ref types */
794 (*p
== '(') || (*p
== ')') || /* function types */
795 (*p
== '[') || (*p
== ']'))) /* array types */
810 /* Return a null-terminated temporary copy of the name
811 of a string token. */
817 memcpy (namecopy
, token
.ptr
, token
.length
);
818 namecopy
[token
.length
] = 0;
822 /* Reverse an expression from suffix form (in which it is constructed)
823 to prefix form (in which we can conveniently print or execute it). */
826 prefixify_expression (expr
)
827 register struct expression
*expr
;
830 sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expr
->nelts
);
831 register struct expression
*temp
;
832 register int inpos
= expr
->nelts
, outpos
= 0;
834 temp
= (struct expression
*) alloca (len
);
836 /* Copy the original expression into temp. */
837 memcpy (temp
, expr
, len
);
839 prefixify_subexp (temp
, expr
, inpos
, outpos
);
842 /* Return the number of exp_elements in the subexpression of EXPR
843 whose last exp_element is at index ENDPOS - 1 in EXPR. */
846 length_of_subexp (expr
, endpos
)
847 register struct expression
*expr
;
850 register int oplen
= 1;
851 register int args
= 0;
855 error ("?error in length_of_subexp");
857 i
= (int) expr
->elts
[endpos
- 1].opcode
;
863 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
864 oplen
= 5 + BYTES_TO_EXP_ELEM (oplen
+ 1);
887 case OP_F77_UNDETERMINED_ARGLIST
:
889 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
917 case STRUCTOP_STRUCT
:
925 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
926 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
930 oplen
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
931 oplen
= (oplen
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
932 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
);
937 args
= longest_to_int (expr
->elts
[endpos
- 2].longconst
);
938 args
-= longest_to_int (expr
->elts
[endpos
- 3].longconst
);
944 case TERNOP_SLICE_COUNT
:
949 case MULTI_SUBSCRIPT
:
951 args
= 1 + longest_to_int (expr
->elts
[endpos
- 2].longconst
);
954 case BINOP_ASSIGN_MODIFY
:
965 args
= 1 + (i
< (int) BINOP_END
);
970 oplen
+= length_of_subexp (expr
, endpos
- oplen
);
977 /* Copy the subexpression ending just before index INEND in INEXPR
978 into OUTEXPR, starting at index OUTBEG.
979 In the process, convert it from suffix to prefix form. */
982 prefixify_subexp (inexpr
, outexpr
, inend
, outbeg
)
983 register struct expression
*inexpr
;
984 struct expression
*outexpr
;
988 register int oplen
= 1;
989 register int args
= 0;
992 enum exp_opcode opcode
;
994 /* Compute how long the last operation is (in OPLEN),
995 and also how many preceding subexpressions serve as
996 arguments for it (in ARGS). */
998 opcode
= inexpr
->elts
[inend
- 1].opcode
;
1003 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1004 oplen
= 5 + BYTES_TO_EXP_ELEM (oplen
+ 1);
1017 case OP_INTERNALVAR
:
1027 case OP_F77_UNDETERMINED_ARGLIST
:
1029 args
= 1 + longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1055 case STRUCTOP_STRUCT
:
1064 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1065 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
+ 1);
1069 oplen
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1070 oplen
= (oplen
+ HOST_CHAR_BIT
- 1) / HOST_CHAR_BIT
;
1071 oplen
= 4 + BYTES_TO_EXP_ELEM (oplen
);
1076 args
= longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1077 args
-= longest_to_int (inexpr
->elts
[inend
- 3].longconst
);
1083 case TERNOP_SLICE_COUNT
:
1087 case BINOP_ASSIGN_MODIFY
:
1093 case MULTI_SUBSCRIPT
:
1095 args
= 1 + longest_to_int (inexpr
->elts
[inend
- 2].longconst
);
1104 args
= 1 + ((int) opcode
< (int) BINOP_END
);
1107 /* Copy the final operator itself, from the end of the input
1108 to the beginning of the output. */
1110 memcpy (&outexpr
->elts
[outbeg
], &inexpr
->elts
[inend
],
1111 EXP_ELEM_TO_BYTES (oplen
));
1114 /* Find the lengths of the arg subexpressions. */
1115 arglens
= (int *) alloca (args
* sizeof (int));
1116 for (i
= args
- 1; i
>= 0; i
--)
1118 oplen
= length_of_subexp (inexpr
, inend
);
1123 /* Now copy each subexpression, preserving the order of
1124 the subexpressions, but prefixifying each one.
1125 In this loop, inend starts at the beginning of
1126 the expression this level is working on
1127 and marches forward over the arguments.
1128 outbeg does similarly in the output. */
1129 for (i
= 0; i
< args
; i
++)
1133 prefixify_subexp (inexpr
, outexpr
, inend
, outbeg
);
1138 /* This page contains the two entry points to this file. */
1140 /* Read an expression from the string *STRINGPTR points to,
1141 parse it, and return a pointer to a struct expression that we malloc.
1142 Use block BLOCK as the lexical context for variable names;
1143 if BLOCK is zero, use the block of the selected stack frame.
1144 Meanwhile, advance *STRINGPTR to point after the expression,
1145 at the first nonwhite character that is not part of the expression
1146 (possibly a null character).
1148 If COMMA is nonzero, stop if a comma is reached. */
1151 parse_exp_1 (stringptr
, block
, comma
)
1153 struct block
*block
;
1156 struct cleanup
*old_chain
;
1158 lexptr
= *stringptr
;
1161 type_stack_depth
= 0;
1163 comma_terminates
= comma
;
1165 if (lexptr
== 0 || *lexptr
== 0)
1166 error_no_arg ("expression to compute");
1168 old_chain
= make_cleanup ((make_cleanup_func
) free_funcalls
, 0);
1171 expression_context_block
= block
? block
: get_selected_block ();
1173 namecopy
= (char *) alloca (strlen (lexptr
) + 1);
1176 expout
= (struct expression
*)
1177 xmalloc (sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expout_size
));
1178 expout
->language_defn
= current_language
;
1179 make_cleanup (free_current_contents
, &expout
);
1181 if (current_language
->la_parser ())
1182 current_language
->la_error (NULL
);
1184 discard_cleanups (old_chain
);
1186 /* Record the actual number of expression elements, and then
1187 reallocate the expression memory so that we free up any
1190 expout
->nelts
= expout_ptr
;
1191 expout
= (struct expression
*)
1192 xrealloc ((char *) expout
,
1193 sizeof (struct expression
) + EXP_ELEM_TO_BYTES (expout_ptr
));;
1195 /* Convert expression from postfix form as generated by yacc
1196 parser, to a prefix form. */
1198 if (expressiondebug
)
1199 dump_prefix_expression (expout
, gdb_stdlog
,
1200 "before conversion to prefix form");
1202 prefixify_expression (expout
);
1204 if (expressiondebug
)
1205 dump_postfix_expression (expout
, gdb_stdlog
,
1206 "after conversion to prefix form");
1208 *stringptr
= lexptr
;
1212 /* Parse STRING as an expression, and complain if this fails
1213 to use up all of the contents of STRING. */
1216 parse_expression (string
)
1219 register struct expression
*exp
;
1220 exp
= parse_exp_1 (&string
, 0, 0);
1222 error ("Junk after end of expression.");
1226 /* Stuff for maintaining a stack of types. Currently just used by C, but
1227 probably useful for any language which declares its types "backwards". */
1231 enum type_pieces tp
;
1233 if (type_stack_depth
== type_stack_size
)
1235 type_stack_size
*= 2;
1236 type_stack
= (union type_stack_elt
*)
1237 xrealloc ((char *) type_stack
, type_stack_size
* sizeof (*type_stack
));
1239 type_stack
[type_stack_depth
++].piece
= tp
;
1246 if (type_stack_depth
== type_stack_size
)
1248 type_stack_size
*= 2;
1249 type_stack
= (union type_stack_elt
*)
1250 xrealloc ((char *) type_stack
, type_stack_size
* sizeof (*type_stack
));
1252 type_stack
[type_stack_depth
++].int_val
= n
;
1258 if (type_stack_depth
)
1259 return type_stack
[--type_stack_depth
].piece
;
1266 if (type_stack_depth
)
1267 return type_stack
[--type_stack_depth
].int_val
;
1268 /* "Can't happen". */
1272 /* Pop the type stack and return the type which corresponds to FOLLOW_TYPE
1273 as modified by all the stuff on the stack. */
1275 follow_types (follow_type
)
1276 struct type
*follow_type
;
1280 struct type
*range_type
;
1283 switch (pop_type ())
1289 follow_type
= lookup_pointer_type (follow_type
);
1292 follow_type
= lookup_reference_type (follow_type
);
1295 array_size
= pop_type_int ();
1296 /* FIXME-type-allocation: need a way to free this type when we are
1299 create_range_type ((struct type
*) NULL
,
1300 builtin_type_int
, 0,
1301 array_size
>= 0 ? array_size
- 1 : 0);
1303 create_array_type ((struct type
*) NULL
,
1304 follow_type
, range_type
);
1306 TYPE_ARRAY_UPPER_BOUND_TYPE (follow_type
)
1307 = BOUND_CANNOT_BE_DETERMINED
;
1310 /* FIXME-type-allocation: need a way to free this type when we are
1312 follow_type
= lookup_function_type (follow_type
);
1318 static void build_parse
PARAMS ((void));
1324 msym_text_symbol_type
=
1325 init_type (TYPE_CODE_FUNC
, 1, 0, "<text variable, no debug info>", NULL
);
1326 TYPE_TARGET_TYPE (msym_text_symbol_type
) = builtin_type_int
;
1327 msym_data_symbol_type
=
1328 init_type (TYPE_CODE_INT
, TARGET_INT_BIT
/ HOST_CHAR_BIT
, 0,
1329 "<data variable, no debug info>", NULL
);
1330 msym_unknown_symbol_type
=
1331 init_type (TYPE_CODE_INT
, 1, 0,
1332 "<variable (not text or data), no debug info>",
1335 /* create the std_regs table */
1354 /* create an empty table */
1355 std_regs
= xmalloc ((num_std_regs
+ 1) * sizeof *std_regs
);
1359 std_regs
[i
].name
= "pc";
1360 std_regs
[i
].regnum
= PC_REGNUM
;
1364 std_regs
[i
].name
= "fp";
1365 std_regs
[i
].regnum
= FP_REGNUM
;
1369 std_regs
[i
].name
= "sp";
1370 std_regs
[i
].regnum
= SP_REGNUM
;
1374 std_regs
[i
].name
= "ps";
1375 std_regs
[i
].regnum
= PS_REGNUM
;
1378 memset (&std_regs
[i
], 0, sizeof (std_regs
[i
]));
1382 _initialize_parse ()
1384 type_stack_size
= 80;
1385 type_stack_depth
= 0;
1386 type_stack
= (union type_stack_elt
*)
1387 xmalloc (type_stack_size
* sizeof (*type_stack
));
1391 /* FIXME - For the moment, handle types by swapping them in and out.
1392 Should be using the per-architecture data-pointer and a large
1394 register_gdbarch_swap (&msym_text_symbol_type
, sizeof (msym_text_symbol_type
), NULL
);
1395 register_gdbarch_swap (&msym_data_symbol_type
, sizeof (msym_data_symbol_type
), NULL
);
1396 register_gdbarch_swap (&msym_unknown_symbol_type
, sizeof (msym_unknown_symbol_type
), NULL
);
1398 register_gdbarch_swap (&num_std_regs
, sizeof (std_regs
), NULL
);
1399 register_gdbarch_swap (&std_regs
, sizeof (std_regs
), NULL
);
1400 register_gdbarch_swap (NULL
, 0, build_parse
);
1403 add_set_cmd ("expression", class_maintenance
, var_zinteger
,
1404 (char *) &expressiondebug
,
1405 "Set expression debugging.\n\
1406 When non-zero, the internal representation of expressions will be printed.",