4 * Copyright (C) 2003 Transmeta Corp.
5 * 2003-2004 Linus Torvalds
7 * Licensed under the Open Software License version 1.1
9 * Evaluate constant expressions.
27 #include "expression.h"
29 struct symbol
*current_fn
;
31 static struct symbol
*degenerate(struct expression
*expr
);
32 static struct symbol
*evaluate_symbol(struct symbol
*sym
);
34 static struct symbol
*evaluate_symbol_expression(struct expression
*expr
)
36 struct expression
*addr
;
37 struct symbol
*sym
= expr
->symbol
;
38 struct symbol
*base_type
;
41 expression_error(expr
, "undefined identifier '%s'", show_ident(expr
->symbol_name
));
45 examine_symbol_type(sym
);
47 base_type
= get_base_type(sym
);
49 expression_error(expr
, "identifier '%s' has no type", show_ident(expr
->symbol_name
));
53 addr
= alloc_expression(expr
->pos
, EXPR_SYMBOL
);
55 addr
->symbol_name
= expr
->symbol_name
;
56 addr
->ctype
= &lazy_ptr_ctype
; /* Lazy evaluation: we need to do a proper job if somebody does &sym */
57 expr
->type
= EXPR_PREOP
;
61 /* The type of a symbol is the symbol itself! */
66 static struct symbol
*evaluate_string(struct expression
*expr
)
68 struct symbol
*sym
= alloc_symbol(expr
->pos
, SYM_NODE
);
69 struct symbol
*array
= alloc_symbol(expr
->pos
, SYM_ARRAY
);
70 struct expression
*addr
= alloc_expression(expr
->pos
, EXPR_SYMBOL
);
71 struct expression
*initstr
= alloc_expression(expr
->pos
, EXPR_STRING
);
72 unsigned int length
= expr
->string
->length
;
74 sym
->array_size
= alloc_const_expression(expr
->pos
, length
);
75 sym
->bit_size
= bits_in_char
* length
;
76 sym
->ctype
.alignment
= 1;
78 sym
->ctype
.modifiers
= MOD_STATIC
;
79 sym
->ctype
.base_type
= array
;
80 sym
->initializer
= initstr
;
83 initstr
->string
= expr
->string
;
85 array
->array_size
= sym
->array_size
;
86 array
->bit_size
= bits_in_char
* length
;
87 array
->ctype
.alignment
= 1;
88 array
->ctype
.modifiers
= MOD_STATIC
;
89 array
->ctype
.base_type
= &char_ctype
;
92 addr
->ctype
= &lazy_ptr_ctype
;
94 expr
->type
= EXPR_PREOP
;
101 static inline struct symbol
*integer_promotion(struct symbol
*type
)
103 struct symbol
*orig_type
= type
;
104 unsigned long mod
= type
->ctype
.modifiers
;
107 if (type
->type
== SYM_NODE
)
108 type
= type
->ctype
.base_type
;
109 if (type
->type
== SYM_ENUM
)
110 type
= type
->ctype
.base_type
;
111 width
= type
->bit_size
;
114 * Bitfields always promote to the base type,
115 * even if the bitfield might be bigger than
118 if (type
->type
== SYM_BITFIELD
) {
119 type
= type
->ctype
.base_type
;
122 mod
= type
->ctype
.modifiers
;
123 if (width
< bits_in_int
)
126 /* If char/short has as many bits as int, it still gets "promoted" */
127 if (mod
& (MOD_CHAR
| MOD_SHORT
)) {
128 if (mod
& MOD_UNSIGNED
)
136 * integer part of usual arithmetic conversions:
137 * integer promotions are applied
138 * if left and right are identical, we are done
139 * if signedness is the same, convert one with lower rank
140 * unless unsigned argument has rank lower than signed one, convert the
142 * if signed argument is bigger than unsigned one, convert the unsigned.
143 * otherwise, convert signed.
145 * Leaving aside the integer promotions, that is equivalent to
146 * if identical, don't convert
147 * if left is bigger than right, convert right
148 * if right is bigger than left, convert right
149 * otherwise, if signedness is the same, convert one with lower rank
150 * otherwise convert the signed one.
152 static struct symbol
*bigger_int_type(struct symbol
*left
, struct symbol
*right
)
154 unsigned long lmod
, rmod
;
156 left
= integer_promotion(left
);
157 right
= integer_promotion(right
);
162 if (left
->bit_size
> right
->bit_size
)
165 if (right
->bit_size
> left
->bit_size
)
168 lmod
= left
->ctype
.modifiers
;
169 rmod
= right
->ctype
.modifiers
;
170 if ((lmod
^ rmod
) & MOD_UNSIGNED
) {
171 if (lmod
& MOD_UNSIGNED
)
173 } else if ((lmod
& ~rmod
) & (MOD_LONG
| MOD_LONGLONG
))
181 static int same_cast_type(struct symbol
*orig
, struct symbol
*new)
183 return orig
->bit_size
== new->bit_size
&& orig
->bit_offset
== new->bit_offset
;
186 static struct symbol
*base_type(struct symbol
*node
, unsigned long *modp
, unsigned long *asp
)
188 unsigned long mod
, as
;
192 mod
|= node
->ctype
.modifiers
;
193 as
|= node
->ctype
.as
;
194 if (node
->type
== SYM_NODE
) {
195 node
= node
->ctype
.base_type
;
200 *modp
= mod
& ~MOD_IGNORE
;
205 static int is_same_type(struct expression
*expr
, struct symbol
*new)
207 struct symbol
*old
= expr
->ctype
;
208 unsigned long oldmod
, newmod
, oldas
, newas
;
210 old
= base_type(old
, &oldmod
, &oldas
);
211 new = base_type(new, &newmod
, &newas
);
213 /* Same base type, same address space? */
214 if (old
== new && oldas
== newas
) {
215 unsigned long difmod
;
217 /* Check the modifier bits. */
218 difmod
= (oldmod
^ newmod
) & ~MOD_NOCAST
;
220 /* Exact same type? */
225 * Not the same type, but differs only in "const".
226 * Don't warn about MOD_NOCAST.
228 if (difmod
== MOD_CONST
)
231 if ((oldmod
| newmod
) & MOD_NOCAST
) {
232 const char *tofrom
= "to/from";
233 if (!(newmod
& MOD_NOCAST
))
235 if (!(oldmod
& MOD_NOCAST
))
237 warning(expr
->pos
, "implicit cast %s nocast type", tofrom
);
243 warn_for_different_enum_types (struct position pos
,
244 struct symbol
*typea
,
245 struct symbol
*typeb
)
249 if (typea
->type
== SYM_NODE
)
250 typea
= typea
->ctype
.base_type
;
251 if (typeb
->type
== SYM_NODE
)
252 typeb
= typeb
->ctype
.base_type
;
257 if (typea
->type
== SYM_ENUM
&& typeb
->type
== SYM_ENUM
) {
258 warning(pos
, "mixing different enum types");
259 info(pos
, " %s versus", show_typename(typea
));
260 info(pos
, " %s", show_typename(typeb
));
265 * This gets called for implicit casts in assignments and
266 * integer promotion. We often want to try to move the
267 * cast down, because the ops involved may have been
268 * implicitly cast up, and we can get rid of the casts
271 static struct expression
* cast_to(struct expression
*old
, struct symbol
*type
)
273 struct expression
*expr
;
275 warn_for_different_enum_types (old
->pos
, old
->ctype
, type
);
277 if (is_same_type(old
, type
))
281 * See if we can simplify the op. Move the cast down.
285 if (old
->ctype
->bit_size
< type
->bit_size
)
287 if (old
->op
== '~') {
289 old
->unop
= cast_to(old
->unop
, type
);
294 case EXPR_IMPLIED_CAST
:
295 warn_for_different_enum_types(old
->pos
, old
->ctype
, type
);
297 if (old
->ctype
->bit_size
>= type
->bit_size
) {
298 struct expression
*orig
= old
->cast_expression
;
299 if (same_cast_type(orig
->ctype
, type
))
301 if (old
->ctype
->bit_offset
== type
->bit_offset
) {
303 old
->cast_type
= type
;
313 expr
= alloc_expression(old
->pos
, EXPR_IMPLIED_CAST
);
315 expr
->cast_type
= type
;
316 expr
->cast_expression
= old
;
320 static int is_type_type(struct symbol
*type
)
322 return (type
->ctype
.modifiers
& MOD_TYPE
) != 0;
325 int is_ptr_type(struct symbol
*type
)
327 if (type
->type
== SYM_NODE
)
328 type
= type
->ctype
.base_type
;
329 return type
->type
== SYM_PTR
|| type
->type
== SYM_ARRAY
|| type
->type
== SYM_FN
;
332 static inline int is_float_type(struct symbol
*type
)
334 if (type
->type
== SYM_NODE
)
335 type
= type
->ctype
.base_type
;
336 return type
->ctype
.base_type
== &fp_type
;
339 static inline int is_byte_type(struct symbol
*type
)
341 return type
->bit_size
== bits_in_char
&& type
->type
!= SYM_BITFIELD
;
354 static inline int classify_type(struct symbol
*type
, struct symbol
**base
)
356 static int type_class
[SYM_BAD
+ 1] = {
357 [SYM_PTR
] = TYPE_PTR
,
359 [SYM_ARRAY
] = TYPE_PTR
| TYPE_COMPOUND
,
360 [SYM_STRUCT
] = TYPE_COMPOUND
,
361 [SYM_UNION
] = TYPE_COMPOUND
,
362 [SYM_BITFIELD
] = TYPE_NUM
| TYPE_BITFIELD
,
363 [SYM_RESTRICT
] = TYPE_NUM
| TYPE_RESTRICT
,
364 [SYM_FOULED
] = TYPE_NUM
| TYPE_RESTRICT
| TYPE_FOULED
,
366 if (type
->type
== SYM_NODE
)
367 type
= type
->ctype
.base_type
;
368 if (type
->type
== SYM_ENUM
)
369 type
= type
->ctype
.base_type
;
371 if (type
->type
== SYM_BASETYPE
) {
372 if (type
->ctype
.base_type
== &int_type
)
374 if (type
->ctype
.base_type
== &fp_type
)
375 return TYPE_NUM
| TYPE_FLOAT
;
377 return type_class
[type
->type
];
380 #define is_int(class) ((class & (TYPE_NUM | TYPE_FLOAT)) == TYPE_NUM)
382 static inline int is_string_type(struct symbol
*type
)
384 if (type
->type
== SYM_NODE
)
385 type
= type
->ctype
.base_type
;
386 return type
->type
== SYM_ARRAY
&& is_byte_type(type
->ctype
.base_type
);
389 static struct symbol
*bad_expr_type(struct expression
*expr
)
391 sparse_error(expr
->pos
, "incompatible types for operation (%s)", show_special(expr
->op
));
392 switch (expr
->type
) {
395 info(expr
->pos
, " left side has type %s", show_typename(expr
->left
->ctype
));
396 info(expr
->pos
, " right side has type %s", show_typename(expr
->right
->ctype
));
400 info(expr
->pos
, " argument has type %s", show_typename(expr
->unop
->ctype
));
406 return expr
->ctype
= &bad_ctype
;
409 static int restricted_value(struct expression
*v
, struct symbol
*type
)
411 if (v
->type
!= EXPR_VALUE
)
418 static int restricted_binop(int op
, struct symbol
*type
)
423 case SPECIAL_AND_ASSIGN
:
424 case SPECIAL_OR_ASSIGN
:
425 case SPECIAL_XOR_ASSIGN
:
426 return 1; /* unfoul */
430 return 2; /* keep fouled */
432 case SPECIAL_NOTEQUAL
:
433 return 3; /* warn if fouled */
439 static int restricted_unop(int op
, struct symbol
**type
)
442 if ((*type
)->bit_size
< bits_in_int
)
443 *type
= befoul(*type
);
450 static struct symbol
*restricted_binop_type(int op
,
451 struct expression
*left
,
452 struct expression
*right
,
453 int lclass
, int rclass
,
454 struct symbol
*ltype
,
455 struct symbol
*rtype
)
457 struct symbol
*ctype
= NULL
;
458 if (lclass
& TYPE_RESTRICT
) {
459 if (rclass
& TYPE_RESTRICT
) {
460 if (ltype
== rtype
) {
462 } else if (lclass
& TYPE_FOULED
) {
463 if (ltype
->ctype
.base_type
== rtype
)
465 } else if (rclass
& TYPE_FOULED
) {
466 if (rtype
->ctype
.base_type
== ltype
)
470 if (!restricted_value(right
, ltype
))
473 } else if (!restricted_value(left
, rtype
))
477 switch (restricted_binop(op
, ctype
)) {
479 if ((lclass
^ rclass
) & TYPE_FOULED
)
480 ctype
= ctype
->ctype
.base_type
;
483 if (!(lclass
& rclass
& TYPE_FOULED
))
495 static inline void unrestrict(struct expression
*expr
,
496 int class, struct symbol
**ctype
)
498 if (class & TYPE_RESTRICT
) {
499 warning(expr
->pos
, "restricted degrades to integer");
500 if (class & TYPE_FOULED
) /* unfoul it first */
501 *ctype
= (*ctype
)->ctype
.base_type
;
502 *ctype
= (*ctype
)->ctype
.base_type
; /* get to arithmetic type */
506 static struct symbol
*usual_conversions(int op
,
507 struct expression
*left
,
508 struct expression
*right
,
509 int lclass
, int rclass
,
510 struct symbol
*ltype
,
511 struct symbol
*rtype
)
513 struct symbol
*ctype
;
515 warn_for_different_enum_types(right
->pos
, left
->ctype
, right
->ctype
);
517 if ((lclass
| rclass
) & TYPE_RESTRICT
)
521 if (!(lclass
& TYPE_FLOAT
)) {
522 if (!(rclass
& TYPE_FLOAT
))
523 return bigger_int_type(ltype
, rtype
);
526 } else if (rclass
& TYPE_FLOAT
) {
527 unsigned long lmod
= ltype
->ctype
.modifiers
;
528 unsigned long rmod
= rtype
->ctype
.modifiers
;
529 if (rmod
& ~lmod
& (MOD_LONG
| MOD_LONGLONG
))
537 ctype
= restricted_binop_type(op
, left
, right
,
538 lclass
, rclass
, ltype
, rtype
);
542 unrestrict(left
, lclass
, <ype
);
543 unrestrict(right
, rclass
, &rtype
);
548 static inline int lvalue_expression(struct expression
*expr
)
550 return expr
->type
== EXPR_PREOP
&& expr
->op
== '*';
553 static int ptr_object_size(struct symbol
*ptr_type
)
555 if (ptr_type
->type
== SYM_NODE
)
556 ptr_type
= ptr_type
->ctype
.base_type
;
557 if (ptr_type
->type
== SYM_PTR
)
558 ptr_type
= get_base_type(ptr_type
);
559 return ptr_type
->bit_size
;
562 static struct symbol
*evaluate_ptr_add(struct expression
*expr
, struct symbol
*ctype
, struct symbol
*itype
)
564 struct expression
*index
= expr
->right
;
568 examine_symbol_type(ctype
);
570 if (!ctype
->ctype
.base_type
) {
571 expression_error(expr
, "missing type information");
575 /* Get the size of whatever the pointer points to */
576 bit_size
= ptr_object_size(ctype
);
577 multiply
= bit_size
>> 3;
581 if (multiply
== 1 && itype
->bit_size
>= bits_in_pointer
)
584 if (index
->type
== EXPR_VALUE
) {
585 struct expression
*val
= alloc_expression(expr
->pos
, EXPR_VALUE
);
586 unsigned long long v
= index
->value
, mask
;
587 mask
= 1ULL << (itype
->bit_size
- 1);
593 mask
= 1ULL << (bits_in_pointer
- 1);
594 v
&= mask
| (mask
- 1);
596 val
->ctype
= ssize_t_ctype
;
601 if (itype
->bit_size
< bits_in_pointer
)
602 index
= cast_to(index
, ssize_t_ctype
);
605 struct expression
*val
= alloc_expression(expr
->pos
, EXPR_VALUE
);
606 struct expression
*mul
= alloc_expression(expr
->pos
, EXPR_BINOP
);
608 val
->ctype
= ssize_t_ctype
;
609 val
->value
= multiply
;
612 mul
->ctype
= ssize_t_ctype
;
622 const char * type_difference(struct symbol
*target
, struct symbol
*source
,
623 unsigned long target_mod_ignore
, unsigned long source_mod_ignore
)
626 unsigned long mod1
, mod2
, diff
;
627 unsigned long as1
, as2
;
629 struct symbol
*base1
, *base2
;
631 if (target
== source
)
633 if (!target
|| !source
)
634 return "different types";
636 * Peel of per-node information.
637 * FIXME! Check alignment and context too here!
639 mod1
= target
->ctype
.modifiers
;
640 as1
= target
->ctype
.as
;
641 mod2
= source
->ctype
.modifiers
;
642 as2
= source
->ctype
.as
;
643 if (target
->type
== SYM_NODE
) {
644 target
= target
->ctype
.base_type
;
647 if (target
->type
== SYM_PTR
) {
651 mod1
|= target
->ctype
.modifiers
;
652 as1
|= target
->ctype
.as
;
654 if (source
->type
== SYM_NODE
) {
655 source
= source
->ctype
.base_type
;
658 if (source
->type
== SYM_PTR
) {
662 mod2
|= source
->ctype
.modifiers
;
663 as2
|= source
->ctype
.as
;
665 if (target
->type
== SYM_ENUM
) {
666 target
= target
->ctype
.base_type
;
670 if (source
->type
== SYM_ENUM
) {
671 source
= source
->ctype
.base_type
;
676 if (target
== source
)
678 if (!target
|| !source
)
679 return "different types";
681 type1
= target
->type
;
682 base1
= target
->ctype
.base_type
;
684 type2
= source
->type
;
685 base2
= source
->ctype
.base_type
;
688 * Pointers to functions compare as the function itself
690 if (type1
== SYM_PTR
&& base1
) {
691 base1
= examine_symbol_type(base1
);
692 switch (base1
->type
) {
696 base1
= base1
->ctype
.base_type
;
701 if (type2
== SYM_PTR
&& base2
) {
702 base2
= examine_symbol_type(base2
);
703 switch (base2
->type
) {
707 base2
= base2
->ctype
.base_type
;
713 /* Arrays degenerate to pointers for type comparisons */
714 type1
= (type1
== SYM_ARRAY
) ? SYM_PTR
: type1
;
715 type2
= (type2
== SYM_ARRAY
) ? SYM_PTR
: type2
;
717 if (type1
!= type2
|| type1
== SYM_RESTRICT
)
718 return "different base types";
720 /* Must be same address space to be comparable */
721 if (Waddress_space
&& as1
!= as2
)
722 return "different address spaces";
724 /* Ignore differences in storage types or addressability */
725 diff
= (mod1
^ mod2
) & ~MOD_IGNORE
;
726 diff
&= (mod1
& ~target_mod_ignore
) | (mod2
& ~source_mod_ignore
);
729 return "different type sizes";
730 if (diff
& ~MOD_SIGNEDNESS
)
731 return "different modifiers";
733 /* Differs in signedness only.. */
736 * Warn if both are explicitly signed ("unsigned" is obviously
737 * always explicit, and since we know one of them has to be
738 * unsigned, we check if the signed one was explicit).
740 if ((mod1
| mod2
) & MOD_EXPLICITLY_SIGNED
)
741 return "different explicit signedness";
744 * "char" matches both "unsigned char" and "signed char",
745 * so if the explicit test didn't trigger, then we should
746 * not warn about a char.
748 if (!(mod1
& MOD_CHAR
))
749 return "different signedness";
753 if (type1
== SYM_FN
) {
755 struct symbol
*arg1
, *arg2
;
756 if (base1
->variadic
!= base2
->variadic
)
757 return "incompatible variadic arguments";
758 PREPARE_PTR_LIST(target
->arguments
, arg1
);
759 PREPARE_PTR_LIST(source
->arguments
, arg2
);
763 diffstr
= type_difference(arg1
, arg2
, 0, 0);
765 static char argdiff
[80];
766 sprintf(argdiff
, "incompatible argument %d (%s)", i
, diffstr
);
775 FINISH_PTR_LIST(arg2
);
776 FINISH_PTR_LIST(arg1
);
785 static int is_null_ptr(struct expression
*expr
)
787 if (expr
->type
!= EXPR_VALUE
|| expr
->value
)
789 if (Wnon_pointer_null
&& !is_ptr_type(expr
->ctype
))
790 warning(expr
->pos
, "Using plain integer as NULL pointer");
795 * Ignore differences in "volatile" and "const"ness when
796 * subtracting pointers
798 #define MOD_IGN (MOD_VOLATILE | MOD_CONST)
800 static struct symbol
*evaluate_ptr_sub(struct expression
*expr
)
802 const char *typediff
;
803 struct symbol
*ctype
;
804 struct symbol
*ltype
, *rtype
;
805 struct expression
*l
= expr
->left
;
806 struct expression
*r
= expr
->right
;
808 ltype
= degenerate(l
);
809 rtype
= degenerate(r
);
812 typediff
= type_difference(ltype
, rtype
, ~MOD_SIZE
, ~MOD_SIZE
);
814 expression_error(expr
, "subtraction of different types can't work (%s)", typediff
);
815 examine_symbol_type(ctype
);
817 /* Figure out the base type we point to */
818 if (ctype
->type
== SYM_NODE
)
819 ctype
= ctype
->ctype
.base_type
;
820 if (ctype
->type
!= SYM_PTR
&& ctype
->type
!= SYM_ARRAY
) {
821 expression_error(expr
, "subtraction of functions? Share your drugs");
824 ctype
= get_base_type(ctype
);
826 expr
->ctype
= ssize_t_ctype
;
827 if (ctype
->bit_size
> bits_in_char
) {
828 struct expression
*sub
= alloc_expression(expr
->pos
, EXPR_BINOP
);
829 struct expression
*div
= expr
;
830 struct expression
*val
= alloc_expression(expr
->pos
, EXPR_VALUE
);
831 unsigned long value
= ctype
->bit_size
>> 3;
833 val
->ctype
= size_t_ctype
;
836 if (value
& (value
-1)) {
837 if (Wptr_subtraction_blows
)
838 warning(expr
->pos
, "potentially expensive pointer subtraction");
842 sub
->ctype
= ssize_t_ctype
;
851 return ssize_t_ctype
;
854 #define is_safe_type(type) ((type)->ctype.modifiers & MOD_SAFE)
856 static struct symbol
*evaluate_conditional(struct expression
*expr
, int iterator
)
858 struct symbol
*ctype
;
863 if (!iterator
&& expr
->type
== EXPR_ASSIGNMENT
&& expr
->op
== '=')
864 warning(expr
->pos
, "assignment expression in conditional");
866 ctype
= evaluate_expression(expr
);
868 if (is_safe_type(ctype
))
869 warning(expr
->pos
, "testing a 'safe expression'");
875 static struct symbol
*evaluate_logical(struct expression
*expr
)
877 if (!evaluate_conditional(expr
->left
, 0))
879 if (!evaluate_conditional(expr
->right
, 0))
882 expr
->ctype
= &bool_ctype
;
886 static struct symbol
*evaluate_binop(struct expression
*expr
)
888 struct symbol
*ltype
, *rtype
, *ctype
;
889 int lclass
= classify_type(expr
->left
->ctype
, <ype
);
890 int rclass
= classify_type(expr
->right
->ctype
, &rtype
);
893 /* number op number */
894 if (lclass
& rclass
& TYPE_NUM
) {
895 if ((lclass
| rclass
) & TYPE_FLOAT
) {
897 case '+': case '-': case '*': case '/':
900 return bad_expr_type(expr
);
904 if (op
== SPECIAL_LEFTSHIFT
|| op
== SPECIAL_RIGHTSHIFT
) {
905 // shifts do integer promotions, but that's it.
906 unrestrict(expr
->left
, lclass
, <ype
);
907 unrestrict(expr
->right
, rclass
, &rtype
);
908 ctype
= ltype
= integer_promotion(ltype
);
909 rtype
= integer_promotion(rtype
);
911 // The rest do usual conversions
912 ltype
= usual_conversions(op
, expr
->left
, expr
->right
,
913 lclass
, rclass
, ltype
, rtype
);
914 ctype
= rtype
= ltype
;
917 expr
->left
= cast_to(expr
->left
, ltype
);
918 expr
->right
= cast_to(expr
->right
, rtype
);
923 /* pointer (+|-) integer */
924 if (lclass
& TYPE_PTR
&& is_int(rclass
) && (op
== '+' || op
== '-')) {
925 unrestrict(expr
->right
, rclass
, &rtype
);
926 return evaluate_ptr_add(expr
, degenerate(expr
->left
), rtype
);
929 /* integer + pointer */
930 if (rclass
& TYPE_PTR
&& is_int(lclass
) && op
== '+') {
931 struct expression
*index
= expr
->left
;
932 unrestrict(index
, lclass
, <ype
);
933 expr
->left
= expr
->right
;
935 return evaluate_ptr_add(expr
, degenerate(expr
->left
), ltype
);
938 /* pointer - pointer */
939 if (lclass
& rclass
& TYPE_PTR
&& expr
->op
== '-')
940 return evaluate_ptr_sub(expr
);
942 return bad_expr_type(expr
);
945 static struct symbol
*evaluate_comma(struct expression
*expr
)
947 expr
->ctype
= expr
->right
->ctype
;
951 static int modify_for_unsigned(int op
)
954 op
= SPECIAL_UNSIGNED_LT
;
956 op
= SPECIAL_UNSIGNED_GT
;
957 else if (op
== SPECIAL_LTE
)
958 op
= SPECIAL_UNSIGNED_LTE
;
959 else if (op
== SPECIAL_GTE
)
960 op
= SPECIAL_UNSIGNED_GTE
;
964 static struct symbol
*evaluate_compare(struct expression
*expr
)
966 struct expression
*left
= expr
->left
, *right
= expr
->right
;
967 struct symbol
*ltype
= left
->ctype
, *rtype
= right
->ctype
;
968 struct symbol
*ctype
;
972 if (is_type_type(ltype
) && is_type_type(rtype
))
975 if (is_safe_type(ltype
) || is_safe_type(rtype
))
976 warning(expr
->pos
, "testing a 'safe expression'");
978 lclass
= classify_type(ltype
, <ype
);
979 rclass
= classify_type(rtype
, &rtype
);
982 if ((lclass
| rclass
) & TYPE_PTR
) {
983 // FIXME! Check the types for compatibility
984 expr
->op
= modify_for_unsigned(expr
->op
);
988 /* Both should be numbers */
989 if (!(lclass
& rclass
& TYPE_NUM
))
990 return bad_expr_type(expr
);
992 ctype
= usual_conversions(expr
->op
, expr
->left
, expr
->right
,
993 lclass
, rclass
, ltype
, rtype
);
994 expr
->left
= cast_to(expr
->left
, ctype
);
995 expr
->right
= cast_to(expr
->right
, ctype
);
996 if (ctype
->ctype
.modifiers
& MOD_UNSIGNED
)
997 expr
->op
= modify_for_unsigned(expr
->op
);
1000 expr
->ctype
= &bool_ctype
;
1005 * FIXME!! This should do casts, array degeneration etc..
1007 static struct symbol
*compatible_ptr_type(struct expression
*left
, struct expression
*right
)
1009 struct symbol
*ltype
= left
->ctype
, *rtype
= right
->ctype
;
1011 if (ltype
->type
== SYM_NODE
)
1012 ltype
= ltype
->ctype
.base_type
;
1014 if (rtype
->type
== SYM_NODE
)
1015 rtype
= rtype
->ctype
.base_type
;
1017 if (ltype
->type
== SYM_PTR
) {
1018 if (is_null_ptr(right
) || rtype
->ctype
.base_type
== &void_ctype
)
1022 if (rtype
->type
== SYM_PTR
) {
1023 if (is_null_ptr(left
) || ltype
->ctype
.base_type
== &void_ctype
)
1030 * NOTE! The degenerate case of "x ? : y", where we don't
1031 * have a true case, this will possibly promote "x" to the
1032 * same type as "y", and thus _change_ the conditional
1033 * test in the expression. But since promotion is "safe"
1034 * for testing, that's OK.
1036 static struct symbol
*evaluate_conditional_expression(struct expression
*expr
)
1038 struct expression
**true;
1039 struct symbol
*ctype
, *ltype
, *rtype
;
1041 const char * typediff
;
1043 if (!evaluate_conditional(expr
->conditional
, 0))
1045 if (!evaluate_expression(expr
->cond_false
))
1048 ctype
= degenerate(expr
->conditional
);
1049 rtype
= degenerate(expr
->cond_false
);
1051 true = &expr
->conditional
;
1053 if (expr
->cond_true
) {
1054 if (!evaluate_expression(expr
->cond_true
))
1056 ltype
= degenerate(expr
->cond_true
);
1057 true = &expr
->cond_true
;
1060 lclass
= classify_type(ltype
, <ype
);
1061 rclass
= classify_type(rtype
, &rtype
);
1062 if (lclass
& rclass
& TYPE_NUM
) {
1063 ctype
= usual_conversions('?', *true, expr
->cond_false
,
1064 lclass
, rclass
, ltype
, rtype
);
1065 *true = cast_to(*true, ctype
);
1066 expr
->cond_false
= cast_to(expr
->cond_false
, ctype
);
1069 ctype
= compatible_ptr_type(*true, expr
->cond_false
);
1073 typediff
= type_difference(ltype
, rtype
, MOD_IGN
, MOD_IGN
);
1076 expression_error(expr
, "incompatible types in conditional expression (%s)", typediff
);
1080 expr
->ctype
= ctype
;
1084 /* FP assignments can not do modulo or bit operations */
1085 static int compatible_float_op(int op
)
1087 return op
== SPECIAL_ADD_ASSIGN
||
1088 op
== SPECIAL_SUB_ASSIGN
||
1089 op
== SPECIAL_MUL_ASSIGN
||
1090 op
== SPECIAL_DIV_ASSIGN
;
1093 static int evaluate_assign_op(struct expression
*expr
)
1095 struct symbol
*target
= expr
->left
->ctype
;
1096 struct symbol
*source
= expr
->right
->ctype
;
1097 struct symbol
*t
, *s
;
1098 int tclass
= classify_type(target
, &t
);
1099 int sclass
= classify_type(source
, &s
);
1102 if (tclass
& sclass
& TYPE_NUM
) {
1103 if (tclass
& TYPE_FLOAT
&& !compatible_float_op(op
)) {
1104 expression_error(expr
, "invalid assignment");
1107 if (tclass
& TYPE_RESTRICT
) {
1108 if (!restricted_binop(op
, t
)) {
1109 expression_error(expr
, "bad restricted assignment");
1112 /* allowed assignments unfoul */
1113 if (sclass
& TYPE_FOULED
&& s
->ctype
.base_type
== t
)
1115 if (!restricted_value(expr
->right
, t
))
1117 } else if (!(sclass
& TYPE_RESTRICT
))
1119 /* source and target would better be identical restricted */
1122 warning(expr
->pos
, "invalid restricted assignment");
1123 expr
->right
= cast_to(expr
->right
, target
);
1126 if (tclass
& TYPE_PTR
&& is_int(sclass
)) {
1127 if (op
== SPECIAL_ADD_ASSIGN
|| op
== SPECIAL_SUB_ASSIGN
) {
1128 unrestrict(expr
->right
, sclass
, &s
);
1129 evaluate_ptr_add(expr
, target
, s
);
1132 expression_error(expr
, "invalid pointer assignment");
1136 expression_error(expr
, "invalid assignment");
1140 expr
->right
= cast_to(expr
->right
, target
);
1144 static int compatible_assignment_types(struct expression
*expr
, struct symbol
*target
,
1145 struct expression
**rp
, struct symbol
*source
, const char *where
)
1147 const char *typediff
;
1148 struct symbol
*t
, *s
;
1150 int tclass
= classify_type(target
, &t
);
1151 int sclass
= classify_type(source
, &s
);
1153 if (tclass
& sclass
& TYPE_NUM
) {
1154 if (tclass
& TYPE_RESTRICT
) {
1155 /* allowed assignments unfoul */
1156 if (sclass
& TYPE_FOULED
&& s
->ctype
.base_type
== t
)
1158 if (!restricted_value(*rp
, target
))
1160 } else if (!(sclass
& TYPE_RESTRICT
))
1164 /* It's OK if the target is more volatile or const than the source */
1165 typediff
= type_difference(target
, source
, MOD_VOLATILE
| MOD_CONST
, 0);
1169 /* Pointer destination? */
1170 if (tclass
& TYPE_PTR
) {
1171 struct expression
*right
= *rp
;
1174 // NULL pointer is always OK
1175 if (is_null_ptr(right
))
1178 /* "void *" matches anything as long as the address space is OK */
1179 target_as
= t
->ctype
.as
| target
->ctype
.as
;
1180 source_as
= s
->ctype
.as
| source
->ctype
.as
;
1181 if (source_as
== target_as
&& (s
->type
== SYM_PTR
|| s
->type
== SYM_ARRAY
)) {
1182 s
= get_base_type(s
);
1183 t
= get_base_type(t
);
1184 if (s
== &void_ctype
|| t
== &void_ctype
)
1189 warning(expr
->pos
, "incorrect type in %s (%s)", where
, typediff
);
1190 info(expr
->pos
, " expected %s", show_typename(target
));
1191 info(expr
->pos
, " got %s", show_typename(source
));
1192 *rp
= cast_to(*rp
, target
);
1195 *rp
= cast_to(*rp
, target
);
1199 static void mark_assigned(struct expression
*expr
)
1205 switch (expr
->type
) {
1210 if (sym
->type
!= SYM_NODE
)
1212 sym
->ctype
.modifiers
|= MOD_ASSIGNED
;
1216 mark_assigned(expr
->left
);
1217 mark_assigned(expr
->right
);
1220 mark_assigned(expr
->cast_expression
);
1223 mark_assigned(expr
->base
);
1231 static void evaluate_assign_to(struct expression
*left
, struct symbol
*type
)
1233 if (type
->ctype
.modifiers
& MOD_CONST
)
1234 expression_error(left
, "assignment to const expression");
1236 /* We know left is an lvalue, so it's a "preop-*" */
1237 mark_assigned(left
->unop
);
1240 static struct symbol
*evaluate_assignment(struct expression
*expr
)
1242 struct expression
*left
= expr
->left
, *right
= expr
->right
;
1243 struct expression
*where
= expr
;
1244 struct symbol
*ltype
, *rtype
;
1246 if (!lvalue_expression(left
)) {
1247 expression_error(expr
, "not an lvalue");
1251 ltype
= left
->ctype
;
1253 if (expr
->op
!= '=') {
1254 if (!evaluate_assign_op(expr
))
1257 rtype
= degenerate(right
);
1258 if (!compatible_assignment_types(where
, ltype
, &where
->right
, rtype
, "assignment"))
1262 evaluate_assign_to(left
, ltype
);
1264 expr
->ctype
= ltype
;
1268 static void examine_fn_arguments(struct symbol
*fn
)
1272 FOR_EACH_PTR(fn
->arguments
, s
) {
1273 struct symbol
*arg
= evaluate_symbol(s
);
1274 /* Array/function arguments silently degenerate into pointers */
1280 ptr
= alloc_symbol(s
->pos
, SYM_PTR
);
1281 if (arg
->type
== SYM_ARRAY
)
1282 ptr
->ctype
= arg
->ctype
;
1284 ptr
->ctype
.base_type
= arg
;
1285 ptr
->ctype
.as
|= s
->ctype
.as
;
1286 ptr
->ctype
.modifiers
|= s
->ctype
.modifiers
& MOD_PTRINHERIT
;
1288 s
->ctype
.base_type
= ptr
;
1290 s
->ctype
.modifiers
&= ~MOD_PTRINHERIT
;
1293 examine_symbol_type(s
);
1300 } END_FOR_EACH_PTR(s
);
1303 static struct symbol
*convert_to_as_mod(struct symbol
*sym
, int as
, int mod
)
1305 /* Take the modifiers of the pointer, and apply them to the member */
1306 mod
|= sym
->ctype
.modifiers
;
1307 if (sym
->ctype
.as
!= as
|| sym
->ctype
.modifiers
!= mod
) {
1308 struct symbol
*newsym
= alloc_symbol(sym
->pos
, SYM_NODE
);
1310 newsym
->ctype
.as
= as
;
1311 newsym
->ctype
.modifiers
= mod
;
1317 static struct symbol
*create_pointer(struct expression
*expr
, struct symbol
*sym
, int degenerate
)
1319 struct symbol
*node
= alloc_symbol(expr
->pos
, SYM_NODE
);
1320 struct symbol
*ptr
= alloc_symbol(expr
->pos
, SYM_PTR
);
1322 node
->ctype
.base_type
= ptr
;
1323 ptr
->bit_size
= bits_in_pointer
;
1324 ptr
->ctype
.alignment
= pointer_alignment
;
1326 node
->bit_size
= bits_in_pointer
;
1327 node
->ctype
.alignment
= pointer_alignment
;
1330 if (sym
->ctype
.modifiers
& MOD_REGISTER
) {
1331 warning(expr
->pos
, "taking address of 'register' variable '%s'", show_ident(sym
->ident
));
1332 sym
->ctype
.modifiers
&= ~MOD_REGISTER
;
1334 if (sym
->type
== SYM_NODE
) {
1335 ptr
->ctype
.as
|= sym
->ctype
.as
;
1336 ptr
->ctype
.modifiers
|= sym
->ctype
.modifiers
& MOD_PTRINHERIT
;
1337 sym
= sym
->ctype
.base_type
;
1339 if (degenerate
&& sym
->type
== SYM_ARRAY
) {
1340 ptr
->ctype
.as
|= sym
->ctype
.as
;
1341 ptr
->ctype
.modifiers
|= sym
->ctype
.modifiers
& MOD_PTRINHERIT
;
1342 sym
= sym
->ctype
.base_type
;
1344 ptr
->ctype
.base_type
= sym
;
1349 /* Arrays degenerate into pointers on pointer arithmetic */
1350 static struct symbol
*degenerate(struct expression
*expr
)
1352 struct symbol
*ctype
, *base
;
1356 ctype
= expr
->ctype
;
1359 base
= examine_symbol_type(ctype
);
1360 if (ctype
->type
== SYM_NODE
)
1361 base
= ctype
->ctype
.base_type
;
1363 * Arrays degenerate into pointers to the entries, while
1364 * functions degenerate into pointers to themselves.
1365 * If array was part of non-lvalue compound, we create a copy
1366 * of that compound first and then act as if we were dealing with
1367 * the corresponding field in there.
1369 switch (base
->type
) {
1371 if (expr
->type
== EXPR_SLICE
) {
1372 struct symbol
*a
= alloc_symbol(expr
->pos
, SYM_NODE
);
1373 struct expression
*e0
, *e1
, *e2
, *e3
, *e4
;
1375 a
->ctype
.base_type
= expr
->base
->ctype
;
1376 a
->bit_size
= expr
->base
->ctype
->bit_size
;
1377 a
->array_size
= expr
->base
->ctype
->array_size
;
1379 e0
= alloc_expression(expr
->pos
, EXPR_SYMBOL
);
1381 e0
->ctype
= &lazy_ptr_ctype
;
1383 e1
= alloc_expression(expr
->pos
, EXPR_PREOP
);
1386 e1
->ctype
= expr
->base
->ctype
; /* XXX */
1388 e2
= alloc_expression(expr
->pos
, EXPR_ASSIGNMENT
);
1390 e2
->right
= expr
->base
;
1392 e2
->ctype
= expr
->base
->ctype
;
1394 if (expr
->r_bitpos
) {
1395 e3
= alloc_expression(expr
->pos
, EXPR_BINOP
);
1398 e3
->right
= alloc_const_expression(expr
->pos
,
1399 expr
->r_bitpos
>> 3);
1400 e3
->ctype
= &lazy_ptr_ctype
;
1405 e4
= alloc_expression(expr
->pos
, EXPR_COMMA
);
1408 e4
->ctype
= &lazy_ptr_ctype
;
1411 expr
->type
= EXPR_PREOP
;
1415 if (expr
->op
!= '*' || expr
->type
!= EXPR_PREOP
) {
1416 expression_error(expr
, "strange non-value function or array");
1419 *expr
= *expr
->unop
;
1420 ctype
= create_pointer(expr
, ctype
, 1);
1421 expr
->ctype
= ctype
;
1428 static struct symbol
*evaluate_addressof(struct expression
*expr
)
1430 struct expression
*op
= expr
->unop
;
1431 struct symbol
*ctype
;
1433 if (op
->op
!= '*' || op
->type
!= EXPR_PREOP
) {
1434 expression_error(expr
, "not addressable");
1440 if (expr
->type
== EXPR_SYMBOL
) {
1441 struct symbol
*sym
= expr
->symbol
;
1442 sym
->ctype
.modifiers
|= MOD_ADDRESSABLE
;
1446 * symbol expression evaluation is lazy about the type
1447 * of the sub-expression, so we may have to generate
1448 * the type here if so..
1450 if (expr
->ctype
== &lazy_ptr_ctype
) {
1451 ctype
= create_pointer(expr
, ctype
, 0);
1452 expr
->ctype
= ctype
;
1458 static struct symbol
*evaluate_dereference(struct expression
*expr
)
1460 struct expression
*op
= expr
->unop
;
1461 struct symbol
*ctype
= op
->ctype
, *node
, *target
;
1463 /* Simplify: *&(expr) => (expr) */
1464 if (op
->type
== EXPR_PREOP
&& op
->op
== '&') {
1469 /* Dereferencing a node drops all the node information. */
1470 if (ctype
->type
== SYM_NODE
)
1471 ctype
= ctype
->ctype
.base_type
;
1473 node
= alloc_symbol(expr
->pos
, SYM_NODE
);
1474 target
= ctype
->ctype
.base_type
;
1476 switch (ctype
->type
) {
1478 expression_error(expr
, "cannot dereference this type");
1481 node
->ctype
.modifiers
= target
->ctype
.modifiers
& MOD_SPECIFIER
;
1482 merge_type(node
, ctype
);
1486 if (!lvalue_expression(op
)) {
1487 expression_error(op
, "non-lvalue array??");
1491 /* Do the implied "addressof" on the array */
1495 * When an array is dereferenced, we need to pick
1496 * up the attributes of the original node too..
1498 merge_type(node
, op
->ctype
);
1499 merge_type(node
, ctype
);
1503 node
->bit_size
= target
->bit_size
;
1504 node
->array_size
= target
->array_size
;
1511 * Unary post-ops: x++ and x--
1513 static struct symbol
*evaluate_postop(struct expression
*expr
)
1515 struct expression
*op
= expr
->unop
;
1516 struct symbol
*ctype
= op
->ctype
;
1518 if (!lvalue_expression(expr
->unop
)) {
1519 expression_error(expr
, "need lvalue expression for ++/--");
1522 if (is_restricted_type(ctype
) && restricted_unop(expr
->op
, &ctype
)) {
1523 expression_error(expr
, "bad operation on restricted");
1525 } else if (is_fouled_type(ctype
) && restricted_unop(expr
->op
, &ctype
)) {
1526 expression_error(expr
, "bad operation on restricted");
1530 evaluate_assign_to(op
, ctype
);
1532 expr
->ctype
= ctype
;
1534 if (is_ptr_type(ctype
))
1535 expr
->op_value
= ptr_object_size(ctype
) >> 3;
1540 static struct symbol
*evaluate_sign(struct expression
*expr
)
1542 struct symbol
*ctype
= expr
->unop
->ctype
;
1543 if (is_int_type(ctype
)) {
1544 struct symbol
*rtype
= rtype
= integer_promotion(ctype
);
1545 expr
->unop
= cast_to(expr
->unop
, rtype
);
1547 } else if (is_float_type(ctype
) && expr
->op
!= '~') {
1548 /* no conversions needed */
1549 } else if (is_restricted_type(ctype
) && !restricted_unop(expr
->op
, &ctype
)) {
1550 /* no conversions needed */
1551 } else if (is_fouled_type(ctype
) && !restricted_unop(expr
->op
, &ctype
)) {
1552 /* no conversions needed */
1554 return bad_expr_type(expr
);
1556 if (expr
->op
== '+')
1557 *expr
= *expr
->unop
;
1558 expr
->ctype
= ctype
;
1562 static struct symbol
*evaluate_preop(struct expression
*expr
)
1564 struct symbol
*ctype
= expr
->unop
->ctype
;
1568 *expr
= *expr
->unop
;
1574 return evaluate_sign(expr
);
1577 return evaluate_dereference(expr
);
1580 return evaluate_addressof(expr
);
1582 case SPECIAL_INCREMENT
:
1583 case SPECIAL_DECREMENT
:
1585 * From a type evaluation standpoint the preops are
1586 * the same as the postops
1588 return evaluate_postop(expr
);
1591 if (is_safe_type(ctype
))
1592 warning(expr
->pos
, "testing a 'safe expression'");
1593 if (is_float_type(ctype
)) {
1594 struct expression
*arg
= expr
->unop
;
1595 expr
->type
= EXPR_BINOP
;
1596 expr
->op
= SPECIAL_EQUAL
;
1598 expr
->right
= alloc_expression(expr
->pos
, EXPR_FVALUE
);
1599 expr
->right
->ctype
= ctype
;
1600 expr
->right
->fvalue
= 0;
1601 } else if (is_fouled_type(ctype
)) {
1602 warning(expr
->pos
, "restricted degrades to integer");
1604 ctype
= &bool_ctype
;
1610 expr
->ctype
= ctype
;
1614 static struct symbol
*find_identifier(struct ident
*ident
, struct symbol_list
*_list
, int *offset
)
1616 struct ptr_list
*head
= (struct ptr_list
*)_list
;
1617 struct ptr_list
*list
= head
;
1623 for (i
= 0; i
< list
->nr
; i
++) {
1624 struct symbol
*sym
= (struct symbol
*) list
->list
[i
];
1626 if (sym
->ident
!= ident
)
1628 *offset
= sym
->offset
;
1631 struct symbol
*ctype
= sym
->ctype
.base_type
;
1635 if (ctype
->type
!= SYM_UNION
&& ctype
->type
!= SYM_STRUCT
)
1637 sub
= find_identifier(ident
, ctype
->symbol_list
, offset
);
1640 *offset
+= sym
->offset
;
1644 } while ((list
= list
->next
) != head
);
1648 static struct expression
*evaluate_offset(struct expression
*expr
, unsigned long offset
)
1650 struct expression
*add
;
1653 * Create a new add-expression
1655 * NOTE! Even if we just add zero, we need a new node
1656 * for the member pointer, since it has a different
1657 * type than the original pointer. We could make that
1658 * be just a cast, but the fact is, a node is a node,
1659 * so we might as well just do the "add zero" here.
1661 add
= alloc_expression(expr
->pos
, EXPR_BINOP
);
1664 add
->right
= alloc_expression(expr
->pos
, EXPR_VALUE
);
1665 add
->right
->ctype
= &int_ctype
;
1666 add
->right
->value
= offset
;
1669 * The ctype of the pointer will be lazily evaluated if
1670 * we ever take the address of this member dereference..
1672 add
->ctype
= &lazy_ptr_ctype
;
1676 /* structure/union dereference */
1677 static struct symbol
*evaluate_member_dereference(struct expression
*expr
)
1680 struct symbol
*ctype
, *member
;
1681 struct expression
*deref
= expr
->deref
, *add
;
1682 struct ident
*ident
= expr
->member
;
1686 if (!evaluate_expression(deref
))
1689 expression_error(expr
, "bad member name");
1693 ctype
= deref
->ctype
;
1694 address_space
= ctype
->ctype
.as
;
1695 mod
= ctype
->ctype
.modifiers
;
1696 if (ctype
->type
== SYM_NODE
) {
1697 ctype
= ctype
->ctype
.base_type
;
1698 address_space
|= ctype
->ctype
.as
;
1699 mod
|= ctype
->ctype
.modifiers
;
1701 if (!ctype
|| (ctype
->type
!= SYM_STRUCT
&& ctype
->type
!= SYM_UNION
)) {
1702 expression_error(expr
, "expected structure or union");
1705 examine_symbol_type(ctype
);
1707 member
= find_identifier(ident
, ctype
->symbol_list
, &offset
);
1709 const char *type
= ctype
->type
== SYM_STRUCT
? "struct" : "union";
1710 const char *name
= "<unnamed>";
1713 name
= ctype
->ident
->name
;
1714 namelen
= ctype
->ident
->len
;
1716 if (ctype
->symbol_list
)
1717 expression_error(expr
, "no member '%s' in %s %.*s",
1718 show_ident(ident
), type
, namelen
, name
);
1720 expression_error(expr
, "using member '%s' in "
1721 "incomplete %s %.*s", show_ident(ident
),
1722 type
, namelen
, name
);
1727 * The member needs to take on the address space and modifiers of
1728 * the "parent" type.
1730 member
= convert_to_as_mod(member
, address_space
, mod
);
1731 ctype
= get_base_type(member
);
1733 if (!lvalue_expression(deref
)) {
1734 if (deref
->type
!= EXPR_SLICE
) {
1738 expr
->base
= deref
->base
;
1739 expr
->r_bitpos
= deref
->r_bitpos
;
1741 expr
->r_bitpos
+= offset
<< 3;
1742 expr
->type
= EXPR_SLICE
;
1743 expr
->r_nrbits
= member
->bit_size
;
1744 expr
->r_bitpos
+= member
->bit_offset
;
1745 expr
->ctype
= member
;
1749 deref
= deref
->unop
;
1750 expr
->deref
= deref
;
1752 add
= evaluate_offset(deref
, offset
);
1753 expr
->type
= EXPR_PREOP
;
1757 expr
->ctype
= member
;
1761 static int is_promoted(struct expression
*expr
)
1764 switch (expr
->type
) {
1767 case EXPR_CONDITIONAL
:
1791 static struct symbol
*evaluate_cast(struct expression
*);
1793 static struct symbol
*evaluate_type_information(struct expression
*expr
)
1795 struct symbol
*sym
= expr
->cast_type
;
1797 sym
= evaluate_expression(expr
->cast_expression
);
1801 * Expressions of restricted types will possibly get
1802 * promoted - check that here
1804 if (is_restricted_type(sym
)) {
1805 if (sym
->bit_size
< bits_in_int
&& is_promoted(expr
))
1807 } else if (is_fouled_type(sym
)) {
1811 examine_symbol_type(sym
);
1812 if (is_bitfield_type(sym
)) {
1813 expression_error(expr
, "trying to examine bitfield type");
1819 static struct symbol
*evaluate_sizeof(struct expression
*expr
)
1821 struct symbol
*type
;
1824 type
= evaluate_type_information(expr
);
1828 size
= type
->bit_size
;
1829 if ((size
< 0) || (size
& 7))
1830 expression_error(expr
, "cannot size expression");
1831 expr
->type
= EXPR_VALUE
;
1832 expr
->value
= size
>> 3;
1833 expr
->ctype
= size_t_ctype
;
1834 return size_t_ctype
;
1837 static struct symbol
*evaluate_ptrsizeof(struct expression
*expr
)
1839 struct symbol
*type
;
1842 type
= evaluate_type_information(expr
);
1846 if (type
->type
== SYM_NODE
)
1847 type
= type
->ctype
.base_type
;
1850 switch (type
->type
) {
1854 type
= get_base_type(type
);
1858 expression_error(expr
, "expected pointer expression");
1861 size
= type
->bit_size
;
1864 expr
->type
= EXPR_VALUE
;
1865 expr
->value
= size
>> 3;
1866 expr
->ctype
= size_t_ctype
;
1867 return size_t_ctype
;
1870 static struct symbol
*evaluate_alignof(struct expression
*expr
)
1872 struct symbol
*type
;
1874 type
= evaluate_type_information(expr
);
1878 expr
->type
= EXPR_VALUE
;
1879 expr
->value
= type
->ctype
.alignment
;
1880 expr
->ctype
= size_t_ctype
;
1881 return size_t_ctype
;
1884 static int evaluate_arguments(struct symbol
*f
, struct symbol
*fn
, struct expression_list
*head
)
1886 struct expression
*expr
;
1887 struct symbol_list
*argument_types
= fn
->arguments
;
1888 struct symbol
*argtype
;
1891 PREPARE_PTR_LIST(argument_types
, argtype
);
1892 FOR_EACH_PTR (head
, expr
) {
1893 struct expression
**p
= THIS_ADDRESS(expr
);
1894 struct symbol
*ctype
, *target
;
1895 ctype
= evaluate_expression(expr
);
1902 struct symbol
*type
;
1903 int class = classify_type(ctype
, &type
);
1904 if (is_int(class)) {
1905 *p
= cast_to(expr
, integer_promotion(type
));
1906 } else if (class & TYPE_FLOAT
) {
1907 unsigned long mod
= type
->ctype
.modifiers
;
1908 if (!(mod
& (MOD_LONG
|MOD_LONGLONG
)))
1909 *p
= cast_to(expr
, &double_ctype
);
1910 } else if (class & TYPE_PTR
) {
1914 static char where
[30];
1915 examine_symbol_type(target
);
1916 sprintf(where
, "argument %d", i
);
1917 ctype
= degenerate(expr
);
1918 compatible_assignment_types(expr
, target
, p
, ctype
, where
);
1922 NEXT_PTR_LIST(argtype
);
1923 } END_FOR_EACH_PTR(expr
);
1924 FINISH_PTR_LIST(argtype
);
1928 static struct symbol
*find_struct_ident(struct symbol
*ctype
, struct ident
*ident
)
1932 FOR_EACH_PTR(ctype
->symbol_list
, sym
) {
1933 if (sym
->ident
== ident
)
1935 } END_FOR_EACH_PTR(sym
);
1939 static void convert_index(struct expression
*e
)
1941 struct expression
*child
= e
->idx_expression
;
1942 unsigned from
= e
->idx_from
;
1943 unsigned to
= e
->idx_to
+ 1;
1945 e
->init_offset
= from
* (e
->ctype
->bit_size
>>3);
1946 e
->init_nr
= to
- from
;
1947 e
->init_expr
= child
;
1950 static void convert_ident(struct expression
*e
)
1952 struct expression
*child
= e
->ident_expression
;
1953 struct symbol
*sym
= e
->field
;
1955 e
->init_offset
= sym
->offset
;
1957 e
->init_expr
= child
;
1960 static void convert_designators(struct expression
*e
)
1963 if (e
->type
== EXPR_INDEX
)
1965 else if (e
->type
== EXPR_IDENTIFIER
)
1973 static void excess(struct expression
*e
, const char *s
)
1975 warning(e
->pos
, "excessive elements in %s initializer", s
);
1979 * implicit designator for the first element
1981 static struct expression
*first_subobject(struct symbol
*ctype
, int class,
1982 struct expression
**v
)
1984 struct expression
*e
= *v
, *new;
1986 if (ctype
->type
== SYM_NODE
)
1987 ctype
= ctype
->ctype
.base_type
;
1989 if (class & TYPE_PTR
) { /* array */
1990 if (!ctype
->bit_size
)
1992 new = alloc_expression(e
->pos
, EXPR_INDEX
);
1993 new->idx_expression
= e
;
1994 new->ctype
= ctype
->ctype
.base_type
;
1996 struct symbol
*field
, *p
;
1997 PREPARE_PTR_LIST(ctype
->symbol_list
, p
);
1998 while (p
&& !p
->ident
&& is_bitfield_type(p
))
2004 new = alloc_expression(e
->pos
, EXPR_IDENTIFIER
);
2005 new->ident_expression
= e
;
2006 new->field
= new->ctype
= field
;
2013 * sanity-check explicit designators; return the innermost one or NULL
2014 * in case of error. Assign types.
2016 static struct expression
*check_designators(struct expression
*e
,
2017 struct symbol
*ctype
)
2019 struct expression
*last
= NULL
;
2022 if (ctype
->type
== SYM_NODE
)
2023 ctype
= ctype
->ctype
.base_type
;
2024 if (e
->type
== EXPR_INDEX
) {
2025 struct symbol
*type
;
2026 if (ctype
->type
!= SYM_ARRAY
) {
2027 err
= "array index in non-array";
2030 type
= ctype
->ctype
.base_type
;
2031 if (ctype
->bit_size
>= 0 && type
->bit_size
>= 0) {
2032 unsigned offset
= e
->idx_to
* type
->bit_size
;
2033 if (offset
>= ctype
->bit_size
) {
2034 err
= "index out of bounds in";
2038 e
->ctype
= ctype
= type
;
2041 if (!e
->idx_expression
) {
2045 e
= e
->idx_expression
;
2046 } else if (e
->type
== EXPR_IDENTIFIER
) {
2047 if (ctype
->type
!= SYM_STRUCT
&& ctype
->type
!= SYM_UNION
) {
2048 err
= "field name not in struct or union";
2051 ctype
= find_struct_ident(ctype
, e
->expr_ident
);
2053 err
= "unknown field name in";
2056 e
->field
= e
->ctype
= ctype
;
2058 if (!e
->ident_expression
) {
2062 e
= e
->ident_expression
;
2063 } else if (e
->type
== EXPR_POS
) {
2064 err
= "internal front-end error: EXPR_POS in";
2069 expression_error(e
, "%s initializer", err
);
2074 * choose the next subobject to initialize.
2076 * Get designators for next element, switch old ones to EXPR_POS.
2077 * Return the resulting expression or NULL if we'd run out of subobjects.
2078 * The innermost designator is returned in *v. Designators in old
2079 * are assumed to be already sanity-checked.
2081 static struct expression
*next_designators(struct expression
*old
,
2082 struct symbol
*ctype
,
2083 struct expression
*e
, struct expression
**v
)
2085 struct expression
*new = NULL
;
2089 if (old
->type
== EXPR_INDEX
) {
2090 struct expression
*copy
;
2093 copy
= next_designators(old
->idx_expression
,
2096 n
= old
->idx_to
+ 1;
2097 if (n
* old
->ctype
->bit_size
== ctype
->bit_size
) {
2102 *v
= new = alloc_expression(e
->pos
, EXPR_INDEX
);
2105 new = alloc_expression(e
->pos
, EXPR_INDEX
);
2108 new->idx_from
= new->idx_to
= n
;
2109 new->idx_expression
= copy
;
2110 new->ctype
= old
->ctype
;
2112 } else if (old
->type
== EXPR_IDENTIFIER
) {
2113 struct expression
*copy
;
2114 struct symbol
*field
;
2116 copy
= next_designators(old
->ident_expression
,
2119 field
= old
->field
->next_subobject
;
2125 *v
= new = alloc_expression(e
->pos
, EXPR_IDENTIFIER
);
2128 new = alloc_expression(e
->pos
, EXPR_IDENTIFIER
);
2132 new->expr_ident
= field
->ident
;
2133 new->ident_expression
= copy
;
2140 static int handle_simple_initializer(struct expression
**ep
, int nested
,
2141 int class, struct symbol
*ctype
);
2144 * deal with traversing subobjects [6.7.8(17,18,20)]
2146 static void handle_list_initializer(struct expression
*expr
,
2147 int class, struct symbol
*ctype
)
2149 struct expression
*e
, *last
= NULL
, *top
= NULL
, *next
;
2152 FOR_EACH_PTR(expr
->expr_list
, e
) {
2153 struct expression
**v
;
2154 struct symbol
*type
;
2157 if (e
->type
!= EXPR_INDEX
&& e
->type
!= EXPR_IDENTIFIER
) {
2160 last
= first_subobject(ctype
, class, &top
);
2162 last
= next_designators(last
, ctype
, e
, &top
);
2165 excess(e
, class & TYPE_PTR
? "array" :
2167 DELETE_CURRENT_PTR(e
);
2171 warning(e
->pos
, "advancing past deep designator");
2174 REPLACE_CURRENT_PTR(e
, last
);
2176 next
= check_designators(e
, ctype
);
2178 DELETE_CURRENT_PTR(e
);
2182 /* deeper than one designator? */
2184 convert_designators(last
);
2189 lclass
= classify_type(top
->ctype
, &type
);
2190 if (top
->type
== EXPR_INDEX
)
2191 v
= &top
->idx_expression
;
2193 v
= &top
->ident_expression
;
2195 if (handle_simple_initializer(v
, 1, lclass
, top
->ctype
))
2198 if (!(lclass
& TYPE_COMPOUND
)) {
2199 warning(e
->pos
, "bogus scalar initializer");
2200 DELETE_CURRENT_PTR(e
);
2204 next
= first_subobject(type
, lclass
, v
);
2206 warning(e
->pos
, "missing braces around initializer");
2211 DELETE_CURRENT_PTR(e
);
2212 excess(e
, lclass
& TYPE_PTR
? "array" : "struct or union");
2214 } END_FOR_EACH_PTR(e
);
2216 convert_designators(last
);
2217 expr
->ctype
= ctype
;
2220 static int is_string_literal(struct expression
**v
)
2222 struct expression
*e
= *v
;
2223 while (e
&& e
->type
== EXPR_PREOP
&& e
->op
== '(')
2225 if (!e
|| e
->type
!= EXPR_STRING
)
2227 if (e
!= *v
&& Wparen_string
)
2229 "array initialized from parenthesized string constant");
2235 * We want a normal expression, possibly in one layer of braces. Warn
2236 * if the latter happens inside a list (it's legal, but likely to be
2237 * an effect of screwup). In case of anything not legal, we are definitely
2238 * having an effect of screwup, so just fail and let the caller warn.
2240 static struct expression
*handle_scalar(struct expression
*e
, int nested
)
2242 struct expression
*v
= NULL
, *p
;
2246 if (e
->type
!= EXPR_INITIALIZER
)
2249 FOR_EACH_PTR(e
->expr_list
, p
) {
2253 } END_FOR_EACH_PTR(p
);
2257 case EXPR_INITIALIZER
:
2259 case EXPR_IDENTIFIER
:
2265 warning(e
->pos
, "braces around scalar initializer");
2270 * deal with the cases that don't care about subobjects:
2271 * scalar <- assignment expression, possibly in braces [6.7.8(11)]
2272 * character array <- string literal, possibly in braces [6.7.8(14)]
2273 * struct or union <- assignment expression of compatible type [6.7.8(13)]
2274 * compound type <- initializer list in braces [6.7.8(16)]
2275 * The last one punts to handle_list_initializer() which, in turn will call
2276 * us for individual elements of the list.
2278 * We do not handle 6.7.8(15) (wide char array <- wide string literal) for
2279 * the lack of support of wide char stuff in general.
2281 * One note: we need to take care not to evaluate a string literal until
2282 * we know that we *will* handle it right here. Otherwise we would screw
2283 * the cases like struct { struct {char s[10]; ...} ...} initialized with
2284 * { "string", ...} - we need to preserve that string literal recognizable
2285 * until we dig into the inner struct.
2287 static int handle_simple_initializer(struct expression
**ep
, int nested
,
2288 int class, struct symbol
*ctype
)
2290 int is_string
= is_string_type(ctype
);
2291 struct expression
*e
= *ep
, *p
;
2292 struct symbol
*type
;
2298 if (!(class & TYPE_COMPOUND
)) {
2299 e
= handle_scalar(e
, nested
);
2303 type
= evaluate_expression(e
);
2306 compatible_assignment_types(e
, ctype
, ep
, degenerate(e
),
2312 * sublist; either a string, or we dig in; the latter will deal with
2313 * pathologies, so we don't need anything fancy here.
2315 if (e
->type
== EXPR_INITIALIZER
) {
2317 struct expression
*v
= NULL
;
2320 FOR_EACH_PTR(e
->expr_list
, p
) {
2324 } END_FOR_EACH_PTR(p
);
2325 if (count
== 1 && is_string_literal(&v
)) {
2330 handle_list_initializer(e
, class, ctype
);
2335 if (is_string_literal(&e
)) {
2336 /* either we are doing array of char, or we'll have to dig in */
2343 /* struct or union can be initialized by compatible */
2344 if (class != TYPE_COMPOUND
)
2346 type
= evaluate_expression(e
);
2349 if (ctype
->type
== SYM_NODE
)
2350 ctype
= ctype
->ctype
.base_type
;
2351 if (type
->type
== SYM_NODE
)
2352 type
= type
->ctype
.base_type
;
2358 p
= alloc_expression(e
->pos
, EXPR_STRING
);
2360 type
= evaluate_expression(p
);
2361 if (ctype
->bit_size
!= -1 &&
2362 ctype
->bit_size
+ bits_in_char
< type
->bit_size
) {
2364 "too long initializer-string for array of char");
2370 static void evaluate_initializer(struct symbol
*ctype
, struct expression
**ep
)
2372 struct symbol
*type
;
2373 int class = classify_type(ctype
, &type
);
2374 if (!handle_simple_initializer(ep
, 0, class, ctype
))
2375 expression_error(*ep
, "invalid initializer");
2378 static int get_as(struct symbol
*sym
)
2386 mod
= sym
->ctype
.modifiers
;
2387 if (sym
->type
== SYM_NODE
) {
2388 sym
= sym
->ctype
.base_type
;
2389 as
|= sym
->ctype
.as
;
2390 mod
|= sym
->ctype
.modifiers
;
2394 * At least for now, allow casting to a "unsigned long".
2395 * That's how we do things like pointer arithmetic and
2396 * store pointers to registers.
2398 if (sym
== &ulong_ctype
)
2401 if (sym
&& sym
->type
== SYM_PTR
) {
2402 sym
= get_base_type(sym
);
2403 as
|= sym
->ctype
.as
;
2404 mod
|= sym
->ctype
.modifiers
;
2406 if (mod
& MOD_FORCE
)
2411 static void cast_to_as(struct expression
*e
, int as
)
2413 struct expression
*v
= e
->cast_expression
;
2414 struct symbol
*type
= v
->ctype
;
2416 if (!Wcast_to_address_space
)
2419 if (v
->type
!= EXPR_VALUE
|| v
->value
)
2422 /* cast from constant 0 to pointer is OK */
2423 if (is_int_type(type
))
2426 if (type
->type
== SYM_NODE
)
2427 type
= type
->ctype
.base_type
;
2429 if (type
->type
== SYM_PTR
&& type
->ctype
.base_type
== &void_ctype
)
2433 warning(e
->pos
, "cast adds address space to expression (<asn:%d>)", as
);
2436 static struct symbol
*evaluate_cast(struct expression
*expr
)
2438 struct expression
*target
= expr
->cast_expression
;
2439 struct symbol
*ctype
= examine_symbol_type(expr
->cast_type
);
2440 struct symbol
*t1
, *t2
;
2447 expr
->ctype
= ctype
;
2448 expr
->cast_type
= ctype
;
2451 * Special case: a cast can be followed by an
2452 * initializer, in which case we need to pass
2453 * the type value down to that initializer rather
2454 * than trying to evaluate it as an expression
2456 * A more complex case is when the initializer is
2457 * dereferenced as part of a post-fix expression.
2458 * We need to produce an expression that can be dereferenced.
2460 if (target
->type
== EXPR_INITIALIZER
) {
2461 struct symbol
*sym
= expr
->cast_type
;
2462 struct expression
*addr
= alloc_expression(expr
->pos
, EXPR_SYMBOL
);
2464 sym
->initializer
= expr
->cast_expression
;
2465 evaluate_symbol(sym
);
2467 addr
->ctype
= &lazy_ptr_ctype
; /* Lazy eval */
2470 expr
->type
= EXPR_PREOP
;
2478 evaluate_expression(target
);
2481 class1
= classify_type(ctype
, &t1
);
2483 * You can always throw a value away by casting to
2484 * "void" - that's an implicit "force". Note that
2485 * the same is _not_ true of "void *".
2487 if (t1
== &void_ctype
)
2490 if (class1
& TYPE_COMPOUND
)
2491 warning(expr
->pos
, "cast to non-scalar");
2495 expression_error(expr
, "cast from unknown type");
2498 class2
= classify_type(t2
, &t2
);
2500 if (class2
& TYPE_COMPOUND
)
2501 warning(expr
->pos
, "cast from non-scalar");
2503 /* allowed cast unfouls */
2504 if (class2
& TYPE_FOULED
)
2505 t2
= t2
->ctype
.base_type
;
2507 if (!(ctype
->ctype
.modifiers
& MOD_FORCE
) && t1
!= t2
) {
2508 if (class1
& TYPE_RESTRICT
)
2509 warning(expr
->pos
, "cast to restricted type");
2510 if (class2
& TYPE_RESTRICT
)
2511 warning(expr
->pos
, "cast from restricted type");
2514 as1
= get_as(ctype
);
2515 as2
= get_as(target
->ctype
);
2516 if (!as1
&& as2
> 0)
2517 warning(expr
->pos
, "cast removes address space of expression");
2518 if (as1
> 0 && as2
> 0 && as1
!= as2
)
2519 warning(expr
->pos
, "cast between address spaces (<asn:%d>-><asn:%d>)", as2
, as1
);
2520 if (as1
> 0 && !as2
)
2521 cast_to_as(expr
, as1
);
2524 * Casts of constant values are special: they
2525 * can be NULL, and thus need to be simplified
2528 if (target
->type
== EXPR_VALUE
)
2529 cast_value(expr
, ctype
, target
, target
->ctype
);
2536 * Evaluate a call expression with a symbol. This
2537 * should expand inline functions, and evaluate
2540 static int evaluate_symbol_call(struct expression
*expr
)
2542 struct expression
*fn
= expr
->fn
;
2543 struct symbol
*ctype
= fn
->ctype
;
2545 if (fn
->type
!= EXPR_PREOP
)
2548 if (ctype
->op
&& ctype
->op
->evaluate
)
2549 return ctype
->op
->evaluate(expr
);
2551 if (ctype
->ctype
.modifiers
& MOD_INLINE
) {
2553 struct symbol
*curr
= current_fn
;
2554 current_fn
= ctype
->ctype
.base_type
;
2556 ret
= inline_function(expr
, ctype
);
2558 /* restore the old function */
2566 static struct symbol
*evaluate_call(struct expression
*expr
)
2569 struct symbol
*ctype
, *sym
;
2570 struct expression
*fn
= expr
->fn
;
2571 struct expression_list
*arglist
= expr
->args
;
2573 if (!evaluate_expression(fn
))
2575 sym
= ctype
= fn
->ctype
;
2576 if (ctype
->type
== SYM_NODE
)
2577 ctype
= ctype
->ctype
.base_type
;
2578 if (ctype
->type
== SYM_PTR
|| ctype
->type
== SYM_ARRAY
)
2579 ctype
= get_base_type(ctype
);
2581 examine_fn_arguments(ctype
);
2582 if (sym
->type
== SYM_NODE
&& fn
->type
== EXPR_PREOP
&&
2583 sym
->op
&& sym
->op
->args
) {
2584 if (!sym
->op
->args(expr
))
2587 if (!evaluate_arguments(sym
, ctype
, arglist
))
2589 if (ctype
->type
!= SYM_FN
) {
2590 expression_error(expr
, "not a function %s",
2591 show_ident(sym
->ident
));
2594 args
= expression_list_size(expr
->args
);
2595 fnargs
= symbol_list_size(ctype
->arguments
);
2597 expression_error(expr
,
2598 "not enough arguments for function %s",
2599 show_ident(sym
->ident
));
2600 if (args
> fnargs
&& !ctype
->variadic
)
2601 expression_error(expr
,
2602 "too many arguments for function %s",
2603 show_ident(sym
->ident
));
2605 if (sym
->type
== SYM_NODE
) {
2606 if (evaluate_symbol_call(expr
))
2609 expr
->ctype
= ctype
->ctype
.base_type
;
2613 struct symbol
*evaluate_expression(struct expression
*expr
)
2620 switch (expr
->type
) {
2623 expression_error(expr
, "value expression without a type");
2626 return evaluate_string(expr
);
2628 return evaluate_symbol_expression(expr
);
2630 if (!evaluate_expression(expr
->left
))
2632 if (!evaluate_expression(expr
->right
))
2634 return evaluate_binop(expr
);
2636 return evaluate_logical(expr
);
2638 evaluate_expression(expr
->left
);
2639 if (!evaluate_expression(expr
->right
))
2641 return evaluate_comma(expr
);
2643 if (!evaluate_expression(expr
->left
))
2645 if (!evaluate_expression(expr
->right
))
2647 return evaluate_compare(expr
);
2648 case EXPR_ASSIGNMENT
:
2649 if (!evaluate_expression(expr
->left
))
2651 if (!evaluate_expression(expr
->right
))
2653 return evaluate_assignment(expr
);
2655 if (!evaluate_expression(expr
->unop
))
2657 return evaluate_preop(expr
);
2659 if (!evaluate_expression(expr
->unop
))
2661 return evaluate_postop(expr
);
2663 case EXPR_IMPLIED_CAST
:
2664 return evaluate_cast(expr
);
2666 return evaluate_sizeof(expr
);
2667 case EXPR_PTRSIZEOF
:
2668 return evaluate_ptrsizeof(expr
);
2670 return evaluate_alignof(expr
);
2672 return evaluate_member_dereference(expr
);
2674 return evaluate_call(expr
);
2676 case EXPR_CONDITIONAL
:
2677 return evaluate_conditional_expression(expr
);
2678 case EXPR_STATEMENT
:
2679 expr
->ctype
= evaluate_statement(expr
->statement
);
2683 expr
->ctype
= &ptr_ctype
;
2687 /* Evaluate the type of the symbol .. */
2688 evaluate_symbol(expr
->symbol
);
2689 /* .. but the type of the _expression_ is a "type" */
2690 expr
->ctype
= &type_ctype
;
2693 /* These can not exist as stand-alone expressions */
2694 case EXPR_INITIALIZER
:
2695 case EXPR_IDENTIFIER
:
2698 expression_error(expr
, "internal front-end error: initializer in expression");
2701 expression_error(expr
, "internal front-end error: SLICE re-evaluated");
2707 static void check_duplicates(struct symbol
*sym
)
2710 struct symbol
*next
= sym
;
2712 while ((next
= next
->same_symbol
) != NULL
) {
2713 const char *typediff
;
2714 evaluate_symbol(next
);
2716 typediff
= type_difference(sym
, next
, 0, 0);
2718 sparse_error(sym
->pos
, "symbol '%s' redeclared with different type (originally declared at %s:%d) - %s",
2719 show_ident(sym
->ident
),
2720 stream_name(next
->pos
.stream
), next
->pos
.line
, typediff
);
2725 unsigned long mod
= sym
->ctype
.modifiers
;
2726 if (mod
& (MOD_STATIC
| MOD_REGISTER
))
2728 if (!(mod
& MOD_TOPLEVEL
))
2732 if (sym
->ident
== &main_ident
)
2734 warning(sym
->pos
, "symbol '%s' was not declared. Should it be static?", show_ident(sym
->ident
));
2738 static struct symbol
*evaluate_symbol(struct symbol
*sym
)
2740 struct symbol
*base_type
;
2748 sym
= examine_symbol_type(sym
);
2749 base_type
= get_base_type(sym
);
2753 /* Evaluate the initializers */
2754 if (sym
->initializer
)
2755 evaluate_initializer(sym
, &sym
->initializer
);
2757 /* And finally, evaluate the body of the symbol too */
2758 if (base_type
->type
== SYM_FN
) {
2759 struct symbol
*curr
= current_fn
;
2761 current_fn
= base_type
;
2763 examine_fn_arguments(base_type
);
2764 if (!base_type
->stmt
&& base_type
->inline_stmt
)
2766 if (base_type
->stmt
)
2767 evaluate_statement(base_type
->stmt
);
2775 void evaluate_symbol_list(struct symbol_list
*list
)
2779 FOR_EACH_PTR(list
, sym
) {
2780 evaluate_symbol(sym
);
2781 check_duplicates(sym
);
2782 } END_FOR_EACH_PTR(sym
);
2785 static struct symbol
*evaluate_return_expression(struct statement
*stmt
)
2787 struct expression
*expr
= stmt
->expression
;
2788 struct symbol
*ctype
, *fntype
;
2790 evaluate_expression(expr
);
2791 ctype
= degenerate(expr
);
2792 fntype
= current_fn
->ctype
.base_type
;
2793 if (!fntype
|| fntype
== &void_ctype
) {
2794 if (expr
&& ctype
!= &void_ctype
)
2795 expression_error(expr
, "return expression in %s function", fntype
?"void":"typeless");
2800 sparse_error(stmt
->pos
, "return with no return value");
2805 compatible_assignment_types(expr
, fntype
, &stmt
->expression
, ctype
, "return expression");
2809 static void evaluate_if_statement(struct statement
*stmt
)
2811 if (!stmt
->if_conditional
)
2814 evaluate_conditional(stmt
->if_conditional
, 0);
2815 evaluate_statement(stmt
->if_true
);
2816 evaluate_statement(stmt
->if_false
);
2819 static void evaluate_iterator(struct statement
*stmt
)
2821 evaluate_conditional(stmt
->iterator_pre_condition
, 1);
2822 evaluate_conditional(stmt
->iterator_post_condition
,1);
2823 evaluate_statement(stmt
->iterator_pre_statement
);
2824 evaluate_statement(stmt
->iterator_statement
);
2825 evaluate_statement(stmt
->iterator_post_statement
);
2828 static void verify_output_constraint(struct expression
*expr
, const char *constraint
)
2830 switch (*constraint
) {
2831 case '=': /* Assignment */
2832 case '+': /* Update */
2835 expression_error(expr
, "output constraint is not an assignment constraint (\"%s\")", constraint
);
2839 static void verify_input_constraint(struct expression
*expr
, const char *constraint
)
2841 switch (*constraint
) {
2842 case '=': /* Assignment */
2843 case '+': /* Update */
2844 expression_error(expr
, "input constraint with assignment (\"%s\")", constraint
);
2848 static void evaluate_asm_statement(struct statement
*stmt
)
2850 struct expression
*expr
;
2853 expr
= stmt
->asm_string
;
2854 if (!expr
|| expr
->type
!= EXPR_STRING
) {
2855 sparse_error(stmt
->pos
, "need constant string for inline asm");
2860 FOR_EACH_PTR(stmt
->asm_outputs
, expr
) {
2861 struct ident
*ident
;
2864 case 0: /* Identifier */
2866 ident
= (struct ident
*)expr
;
2869 case 1: /* Constraint */
2871 if (!expr
|| expr
->type
!= EXPR_STRING
) {
2872 sparse_error(expr
? expr
->pos
: stmt
->pos
, "asm output constraint is not a string");
2873 *THIS_ADDRESS(expr
) = NULL
;
2876 verify_output_constraint(expr
, expr
->string
->data
);
2879 case 2: /* Expression */
2881 if (!evaluate_expression(expr
))
2883 if (!lvalue_expression(expr
))
2884 warning(expr
->pos
, "asm output is not an lvalue");
2885 evaluate_assign_to(expr
, expr
->ctype
);
2888 } END_FOR_EACH_PTR(expr
);
2891 FOR_EACH_PTR(stmt
->asm_inputs
, expr
) {
2892 struct ident
*ident
;
2895 case 0: /* Identifier */
2897 ident
= (struct ident
*)expr
;
2900 case 1: /* Constraint */
2902 if (!expr
|| expr
->type
!= EXPR_STRING
) {
2903 sparse_error(expr
? expr
->pos
: stmt
->pos
, "asm input constraint is not a string");
2904 *THIS_ADDRESS(expr
) = NULL
;
2907 verify_input_constraint(expr
, expr
->string
->data
);
2910 case 2: /* Expression */
2912 if (!evaluate_expression(expr
))
2916 } END_FOR_EACH_PTR(expr
);
2918 FOR_EACH_PTR(stmt
->asm_clobbers
, expr
) {
2920 sparse_error(stmt
->pos
, "bad asm output");
2923 if (expr
->type
== EXPR_STRING
)
2925 expression_error(expr
, "asm clobber is not a string");
2926 } END_FOR_EACH_PTR(expr
);
2929 static void evaluate_case_statement(struct statement
*stmt
)
2931 evaluate_expression(stmt
->case_expression
);
2932 evaluate_expression(stmt
->case_to
);
2933 evaluate_statement(stmt
->case_statement
);
2936 static void check_case_type(struct expression
*switch_expr
,
2937 struct expression
*case_expr
,
2938 struct expression
**enumcase
)
2940 struct symbol
*switch_type
, *case_type
;
2946 switch_type
= switch_expr
->ctype
;
2947 case_type
= evaluate_expression(case_expr
);
2949 if (!switch_type
|| !case_type
)
2953 warn_for_different_enum_types(case_expr
->pos
, case_type
, (*enumcase
)->ctype
);
2954 else if (is_enum_type(case_type
))
2955 *enumcase
= case_expr
;
2958 sclass
= classify_type(switch_type
, &switch_type
);
2959 cclass
= classify_type(case_type
, &case_type
);
2961 /* both should be arithmetic */
2962 if (!(sclass
& cclass
& TYPE_NUM
))
2965 /* neither should be floating */
2966 if ((sclass
| cclass
) & TYPE_FLOAT
)
2969 /* if neither is restricted, we are OK */
2970 if (!((sclass
| cclass
) & TYPE_RESTRICT
))
2973 if (!restricted_binop_type(SPECIAL_EQUAL
, case_expr
, switch_expr
,
2974 cclass
, sclass
, case_type
, switch_type
))
2975 warning(case_expr
->pos
, "restricted degrades to integer");
2980 expression_error(case_expr
, "incompatible types for 'case' statement");
2983 static void evaluate_switch_statement(struct statement
*stmt
)
2986 struct expression
*enumcase
= NULL
;
2987 struct expression
**enumcase_holder
= &enumcase
;
2988 struct expression
*sel
= stmt
->switch_expression
;
2990 evaluate_expression(sel
);
2991 evaluate_statement(stmt
->switch_statement
);
2994 if (sel
->ctype
&& is_enum_type(sel
->ctype
))
2995 enumcase_holder
= NULL
; /* Only check cases against switch */
2997 FOR_EACH_PTR(stmt
->switch_case
->symbol_list
, sym
) {
2998 struct statement
*case_stmt
= sym
->stmt
;
2999 check_case_type(sel
, case_stmt
->case_expression
, enumcase_holder
);
3000 check_case_type(sel
, case_stmt
->case_to
, enumcase_holder
);
3001 } END_FOR_EACH_PTR(sym
);
3004 struct symbol
*evaluate_statement(struct statement
*stmt
)
3009 switch (stmt
->type
) {
3010 case STMT_DECLARATION
: {
3012 FOR_EACH_PTR(stmt
->declaration
, s
) {
3014 } END_FOR_EACH_PTR(s
);
3019 return evaluate_return_expression(stmt
);
3021 case STMT_EXPRESSION
:
3022 if (!evaluate_expression(stmt
->expression
))
3024 return degenerate(stmt
->expression
);
3026 case STMT_COMPOUND
: {
3027 struct statement
*s
;
3028 struct symbol
*type
= NULL
;
3030 /* Evaluate the return symbol in the compound statement */
3031 evaluate_symbol(stmt
->ret
);
3034 * Then, evaluate each statement, making the type of the
3035 * compound statement be the type of the last statement
3037 type
= evaluate_statement(stmt
->args
);
3038 FOR_EACH_PTR(stmt
->stmts
, s
) {
3039 type
= evaluate_statement(s
);
3040 } END_FOR_EACH_PTR(s
);
3046 evaluate_if_statement(stmt
);
3049 evaluate_iterator(stmt
);
3052 evaluate_switch_statement(stmt
);
3055 evaluate_case_statement(stmt
);
3058 return evaluate_statement(stmt
->label_statement
);
3060 evaluate_expression(stmt
->goto_expression
);
3065 evaluate_asm_statement(stmt
);
3068 evaluate_expression(stmt
->expression
);
3071 evaluate_expression(stmt
->range_expression
);
3072 evaluate_expression(stmt
->range_low
);
3073 evaluate_expression(stmt
->range_high
);