| /* Build expressions with type checking for C compiler. |
| Copyright (C) 1987, 88, 91-6, 1997 Free Software Foundation, Inc. |
| |
| This file is part of GNU CC. |
| |
| GNU CC is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU CC is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU CC; see the file COPYING. If not, write to |
| the Free Software Foundation, 59 Temple Place - Suite 330, |
| Boston, MA 02111-1307, USA. */ |
| |
| |
| /* This file is part of the C front end. |
| It contains routines to build C expressions given their operands, |
| including computing the types of the result, C-specific error checks, |
| and some optimization. |
| |
| There are also routines to build RETURN_STMT nodes and CASE_STMT nodes, |
| and to process initializations in declarations (since they work |
| like a strange sort of assignment). */ |
| |
| #include "config.h" |
| #include <stdio.h> |
| #include "tree.h" |
| #include "c-tree.h" |
| #include "flags.h" |
| #include "output.h" |
| |
| /* Nonzero if we've already printed a "missing braces around initializer" |
| message within this initializer. */ |
| static int missing_braces_mentioned; |
| |
| extern char *index (); |
| extern char *rindex (); |
| |
| static tree qualify_type PROTO((tree, tree)); |
| static int comp_target_types PROTO((tree, tree)); |
| static int function_types_compatible_p PROTO((tree, tree)); |
| static int type_lists_compatible_p PROTO((tree, tree)); |
| static int self_promoting_type_p PROTO((tree)); |
| static tree decl_constant_value PROTO((tree)); |
| static tree lookup_field PROTO((tree, tree, tree *)); |
| static tree convert_arguments PROTO((tree, tree, tree, tree)); |
| static tree pointer_int_sum PROTO((enum tree_code, tree, tree)); |
| static tree pointer_diff PROTO((tree, tree)); |
| static tree unary_complex_lvalue PROTO((enum tree_code, tree)); |
| static void pedantic_lvalue_warning PROTO((enum tree_code)); |
| static tree internal_build_compound_expr PROTO((tree, int)); |
| static tree convert_for_assignment PROTO((tree, tree, char *, tree, |
| tree, int)); |
| static void warn_for_assignment PROTO((char *, char *, tree, int)); |
| static tree valid_compound_expr_initializer PROTO((tree, tree)); |
| static void push_string PROTO((char *)); |
| static void push_member_name PROTO((tree)); |
| static void push_array_bounds PROTO((int)); |
| static int spelling_length PROTO((void)); |
| static char *print_spelling PROTO((char *)); |
| static char *get_spelling PROTO((char *)); |
| static void warning_init PROTO((char *, char *, |
| char *)); |
| static tree digest_init PROTO((tree, tree, int, int)); |
| static void check_init_type_bitfields PROTO((tree)); |
| static void output_init_element PROTO((tree, tree, tree, int)); |
| static void output_pending_init_elements PROTO((int)); |
| |
| /* Do `exp = require_complete_type (exp);' to make sure exp |
| does not have an incomplete type. (That includes void types.) */ |
| |
| tree |
| require_complete_type (value) |
| tree value; |
| { |
| tree type = TREE_TYPE (value); |
| |
| /* First, detect a valid value with a complete type. */ |
| if (TYPE_SIZE (type) != 0 |
| && type != void_type_node) |
| return value; |
| |
| incomplete_type_error (value, type); |
| return error_mark_node; |
| } |
| |
| /* Print an error message for invalid use of an incomplete type. |
| VALUE is the expression that was used (or 0 if that isn't known) |
| and TYPE is the type that was invalid. */ |
| |
| void |
| incomplete_type_error (value, type) |
| tree value; |
| tree type; |
| { |
| char *errmsg; |
| |
| /* Avoid duplicate error message. */ |
| if (TREE_CODE (type) == ERROR_MARK) |
| return; |
| |
| if (value != 0 && (TREE_CODE (value) == VAR_DECL |
| || TREE_CODE (value) == PARM_DECL)) |
| error ("`%s' has an incomplete type", |
| IDENTIFIER_POINTER (DECL_NAME (value))); |
| else |
| { |
| retry: |
| /* We must print an error message. Be clever about what it says. */ |
| |
| switch (TREE_CODE (type)) |
| { |
| case RECORD_TYPE: |
| errmsg = "invalid use of undefined type `struct %s'"; |
| break; |
| |
| case UNION_TYPE: |
| errmsg = "invalid use of undefined type `union %s'"; |
| break; |
| |
| case ENUMERAL_TYPE: |
| errmsg = "invalid use of undefined type `enum %s'"; |
| break; |
| |
| case VOID_TYPE: |
| error ("invalid use of void expression"); |
| return; |
| |
| case ARRAY_TYPE: |
| if (TYPE_DOMAIN (type)) |
| { |
| type = TREE_TYPE (type); |
| goto retry; |
| } |
| error ("invalid use of array with unspecified bounds"); |
| return; |
| |
| default: |
| abort (); |
| } |
| |
| if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE) |
| error (errmsg, IDENTIFIER_POINTER (TYPE_NAME (type))); |
| else |
| /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */ |
| error ("invalid use of incomplete typedef `%s'", |
| IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)))); |
| } |
| } |
| |
| /* Return a variant of TYPE which has all the type qualifiers of LIKE |
| as well as those of TYPE. */ |
| |
| static tree |
| qualify_type (type, like) |
| tree type, like; |
| { |
| int constflag = TYPE_READONLY (type) || TYPE_READONLY (like); |
| int volflag = TYPE_VOLATILE (type) || TYPE_VOLATILE (like); |
| return c_build_type_variant (type, constflag, volflag); |
| } |
| |
| /* Return the common type of two types. |
| We assume that comptypes has already been done and returned 1; |
| if that isn't so, this may crash. In particular, we assume that qualifiers |
| match. |
| |
| This is the type for the result of most arithmetic operations |
| if the operands have the given two types. */ |
| |
| tree |
| common_type (t1, t2) |
| tree t1, t2; |
| { |
| register enum tree_code code1; |
| register enum tree_code code2; |
| tree attributes; |
| |
| /* Save time if the two types are the same. */ |
| |
| if (t1 == t2) return t1; |
| |
| /* If one type is nonsense, use the other. */ |
| if (t1 == error_mark_node) |
| return t2; |
| if (t2 == error_mark_node) |
| return t1; |
| |
| /* Merge the attributes */ |
| attributes = merge_attributes (TYPE_ATTRIBUTES (t1), TYPE_ATTRIBUTES (t2)); |
| |
| /* Treat an enum type as the unsigned integer type of the same width. */ |
| |
| if (TREE_CODE (t1) == ENUMERAL_TYPE) |
| t1 = type_for_size (TYPE_PRECISION (t1), 1); |
| if (TREE_CODE (t2) == ENUMERAL_TYPE) |
| t2 = type_for_size (TYPE_PRECISION (t2), 1); |
| |
| code1 = TREE_CODE (t1); |
| code2 = TREE_CODE (t2); |
| |
| /* If one type is complex, form the common type of the non-complex |
| components, then make that complex. Use T1 or T2 if it is the |
| required type. */ |
| if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE) |
| { |
| tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1; |
| tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2; |
| tree subtype = common_type (subtype1, subtype2); |
| |
| if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype) |
| return build_type_attribute_variant (t1, attributes); |
| else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype) |
| return build_type_attribute_variant (t2, attributes); |
| else |
| return build_type_attribute_variant (build_complex_type (subtype), |
| attributes); |
| } |
| |
| switch (code1) |
| { |
| case INTEGER_TYPE: |
| case REAL_TYPE: |
| /* If only one is real, use it as the result. */ |
| |
| if (code1 == REAL_TYPE && code2 != REAL_TYPE) |
| return build_type_attribute_variant (t1, attributes); |
| |
| if (code2 == REAL_TYPE && code1 != REAL_TYPE) |
| return build_type_attribute_variant (t2, attributes); |
| |
| /* Both real or both integers; use the one with greater precision. */ |
| |
| if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2)) |
| return build_type_attribute_variant (t1, attributes); |
| else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1)) |
| return build_type_attribute_variant (t2, attributes); |
| |
| /* Same precision. Prefer longs to ints even when same size. */ |
| |
| if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node |
| || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node) |
| return build_type_attribute_variant (long_unsigned_type_node, |
| attributes); |
| |
| if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node |
| || TYPE_MAIN_VARIANT (t2) == long_integer_type_node) |
| { |
| /* But preserve unsignedness from the other type, |
| since long cannot hold all the values of an unsigned int. */ |
| if (TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2)) |
| t1 = long_unsigned_type_node; |
| else |
| t1 = long_integer_type_node; |
| return build_type_attribute_variant (t1, attributes); |
| } |
| |
| /* Otherwise prefer the unsigned one. */ |
| |
| if (TREE_UNSIGNED (t1)) |
| return build_type_attribute_variant (t1, attributes); |
| else |
| return build_type_attribute_variant (t2, attributes); |
| |
| case POINTER_TYPE: |
| /* For two pointers, do this recursively on the target type, |
| and combine the qualifiers of the two types' targets. */ |
| /* This code was turned off; I don't know why. |
| But ANSI C specifies doing this with the qualifiers. |
| So I turned it on again. */ |
| { |
| tree target = common_type (TYPE_MAIN_VARIANT (TREE_TYPE (t1)), |
| TYPE_MAIN_VARIANT (TREE_TYPE (t2))); |
| int constp |
| = TYPE_READONLY (TREE_TYPE (t1)) || TYPE_READONLY (TREE_TYPE (t2)); |
| int volatilep |
| = TYPE_VOLATILE (TREE_TYPE (t1)) || TYPE_VOLATILE (TREE_TYPE (t2)); |
| t1 = build_pointer_type (c_build_type_variant (target, constp, |
| volatilep)); |
| return build_type_attribute_variant (t1, attributes); |
| } |
| #if 0 |
| t1 = build_pointer_type (common_type (TREE_TYPE (t1), TREE_TYPE (t2))); |
| return build_type_attribute_variant (t1, attributes); |
| #endif |
| |
| case ARRAY_TYPE: |
| { |
| tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2)); |
| /* Save space: see if the result is identical to one of the args. */ |
| if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1)) |
| return build_type_attribute_variant (t1, attributes); |
| if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)) |
| return build_type_attribute_variant (t2, attributes); |
| /* Merge the element types, and have a size if either arg has one. */ |
| t1 = build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2)); |
| return build_type_attribute_variant (t1, attributes); |
| } |
| |
| case FUNCTION_TYPE: |
| /* Function types: prefer the one that specified arg types. |
| If both do, merge the arg types. Also merge the return types. */ |
| { |
| tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2)); |
| tree p1 = TYPE_ARG_TYPES (t1); |
| tree p2 = TYPE_ARG_TYPES (t2); |
| int len; |
| tree newargs, n; |
| int i; |
| |
| /* Save space: see if the result is identical to one of the args. */ |
| if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2)) |
| return build_type_attribute_variant (t1, attributes); |
| if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1)) |
| return build_type_attribute_variant (t2, attributes); |
| |
| /* Simple way if one arg fails to specify argument types. */ |
| if (TYPE_ARG_TYPES (t1) == 0) |
| { |
| t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2)); |
| return build_type_attribute_variant (t1, attributes); |
| } |
| if (TYPE_ARG_TYPES (t2) == 0) |
| { |
| t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1)); |
| return build_type_attribute_variant (t1, attributes); |
| } |
| |
| /* If both args specify argument types, we must merge the two |
| lists, argument by argument. */ |
| |
| len = list_length (p1); |
| newargs = 0; |
| |
| for (i = 0; i < len; i++) |
| newargs = tree_cons (NULL_TREE, NULL_TREE, newargs); |
| |
| n = newargs; |
| |
| for (; p1; |
| p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n)) |
| { |
| /* A null type means arg type is not specified. |
| Take whatever the other function type has. */ |
| if (TREE_VALUE (p1) == 0) |
| { |
| TREE_VALUE (n) = TREE_VALUE (p2); |
| goto parm_done; |
| } |
| if (TREE_VALUE (p2) == 0) |
| { |
| TREE_VALUE (n) = TREE_VALUE (p1); |
| goto parm_done; |
| } |
| |
| /* Given wait (union {union wait *u; int *i} *) |
| and wait (union wait *), |
| prefer union wait * as type of parm. */ |
| if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE |
| && TREE_VALUE (p1) != TREE_VALUE (p2)) |
| { |
| tree memb; |
| for (memb = TYPE_FIELDS (TREE_VALUE (p1)); |
| memb; memb = TREE_CHAIN (memb)) |
| if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2))) |
| { |
| TREE_VALUE (n) = TREE_VALUE (p2); |
| if (pedantic) |
| pedwarn ("function types not truly compatible in ANSI C"); |
| goto parm_done; |
| } |
| } |
| if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE |
| && TREE_VALUE (p2) != TREE_VALUE (p1)) |
| { |
| tree memb; |
| for (memb = TYPE_FIELDS (TREE_VALUE (p2)); |
| memb; memb = TREE_CHAIN (memb)) |
| if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1))) |
| { |
| TREE_VALUE (n) = TREE_VALUE (p1); |
| if (pedantic) |
| pedwarn ("function types not truly compatible in ANSI C"); |
| goto parm_done; |
| } |
| } |
| TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2)); |
| parm_done: ; |
| } |
| |
| t1 = build_function_type (valtype, newargs); |
| /* ... falls through ... */ |
| } |
| |
| default: |
| return build_type_attribute_variant (t1, attributes); |
| } |
| |
| } |
| |
| /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment |
| or various other operations. Return 2 if they are compatible |
| but a warning may be needed if you use them together. */ |
| |
| int |
| comptypes (type1, type2) |
| tree type1, type2; |
| { |
| register tree t1 = type1; |
| register tree t2 = type2; |
| int attrval, val; |
| |
| /* Suppress errors caused by previously reported errors. */ |
| |
| if (t1 == t2 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK) |
| return 1; |
| |
| /* Treat an enum type as the integer type of the same width and |
| signedness. */ |
| |
| if (TREE_CODE (t1) == ENUMERAL_TYPE) |
| t1 = type_for_size (TYPE_PRECISION (t1), TREE_UNSIGNED (t1)); |
| if (TREE_CODE (t2) == ENUMERAL_TYPE) |
| t2 = type_for_size (TYPE_PRECISION (t2), TREE_UNSIGNED (t2)); |
| |
| if (t1 == t2) |
| return 1; |
| |
| /* Different classes of types can't be compatible. */ |
| |
| if (TREE_CODE (t1) != TREE_CODE (t2)) return 0; |
| |
| /* Qualifiers must match. */ |
| |
| if (TYPE_READONLY (t1) != TYPE_READONLY (t2)) |
| return 0; |
| if (TYPE_VOLATILE (t1) != TYPE_VOLATILE (t2)) |
| return 0; |
| |
| /* Allow for two different type nodes which have essentially the same |
| definition. Note that we already checked for equality of the type |
| type qualifiers (just above). */ |
| |
| if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2)) |
| return 1; |
| |
| #ifndef COMP_TYPE_ATTRIBUTES |
| #define COMP_TYPE_ATTRIBUTES(t1,t2) 1 |
| #endif |
| |
| /* 1 if no need for warning yet, 2 if warning cause has been seen. */ |
| if (! (attrval = COMP_TYPE_ATTRIBUTES (t1, t2))) |
| return 0; |
| |
| /* 1 if no need for warning yet, 2 if warning cause has been seen. */ |
| val = 0; |
| |
| switch (TREE_CODE (t1)) |
| { |
| case POINTER_TYPE: |
| val = (TREE_TYPE (t1) == TREE_TYPE (t2) |
| ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2))); |
| break; |
| |
| case FUNCTION_TYPE: |
| val = function_types_compatible_p (t1, t2); |
| break; |
| |
| case ARRAY_TYPE: |
| { |
| tree d1 = TYPE_DOMAIN (t1); |
| tree d2 = TYPE_DOMAIN (t2); |
| val = 1; |
| |
| /* Target types must match incl. qualifiers. */ |
| if (TREE_TYPE (t1) != TREE_TYPE (t2) |
| && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2)))) |
| return 0; |
| |
| /* Sizes must match unless one is missing or variable. */ |
| if (d1 == 0 || d2 == 0 || d1 == d2 |
| || TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST |
| || TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST |
| || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST |
| || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST) |
| break; |
| |
| if (! ((TREE_INT_CST_LOW (TYPE_MIN_VALUE (d1)) |
| == TREE_INT_CST_LOW (TYPE_MIN_VALUE (d2))) |
| && (TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d1)) |
| == TREE_INT_CST_HIGH (TYPE_MIN_VALUE (d2))) |
| && (TREE_INT_CST_LOW (TYPE_MAX_VALUE (d1)) |
| == TREE_INT_CST_LOW (TYPE_MAX_VALUE (d2))) |
| && (TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d1)) |
| == TREE_INT_CST_HIGH (TYPE_MAX_VALUE (d2))))) |
| val = 0; |
| break; |
| } |
| |
| case RECORD_TYPE: |
| if (maybe_objc_comptypes (t1, t2, 0) == 1) |
| val = 1; |
| break; |
| } |
| return attrval == 2 && val == 1 ? 2 : val; |
| } |
| |
| /* Return 1 if TTL and TTR are pointers to types that are equivalent, |
| ignoring their qualifiers. */ |
| |
| static int |
| comp_target_types (ttl, ttr) |
| tree ttl, ttr; |
| { |
| int val; |
| |
| /* Give maybe_objc_comptypes a crack at letting these types through. */ |
| if (val = maybe_objc_comptypes (ttl, ttr, 1) >= 0) |
| return val; |
| |
| val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)), |
| TYPE_MAIN_VARIANT (TREE_TYPE (ttr))); |
| |
| if (val == 2 && pedantic) |
| pedwarn ("types are not quite compatible"); |
| return val; |
| } |
| |
| /* Subroutines of `comptypes'. */ |
| |
| /* Return 1 if two function types F1 and F2 are compatible. |
| If either type specifies no argument types, |
| the other must specify a fixed number of self-promoting arg types. |
| Otherwise, if one type specifies only the number of arguments, |
| the other must specify that number of self-promoting arg types. |
| Otherwise, the argument types must match. */ |
| |
| static int |
| function_types_compatible_p (f1, f2) |
| tree f1, f2; |
| { |
| tree args1, args2; |
| /* 1 if no need for warning yet, 2 if warning cause has been seen. */ |
| int val = 1; |
| int val1; |
| |
| if (!(TREE_TYPE (f1) == TREE_TYPE (f2) |
| || (val = comptypes (TREE_TYPE (f1), TREE_TYPE (f2))))) |
| return 0; |
| |
| args1 = TYPE_ARG_TYPES (f1); |
| args2 = TYPE_ARG_TYPES (f2); |
| |
| /* An unspecified parmlist matches any specified parmlist |
| whose argument types don't need default promotions. */ |
| |
| if (args1 == 0) |
| { |
| if (!self_promoting_args_p (args2)) |
| return 0; |
| /* If one of these types comes from a non-prototype fn definition, |
| compare that with the other type's arglist. |
| If they don't match, ask for a warning (but no error). */ |
| if (TYPE_ACTUAL_ARG_TYPES (f1) |
| && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1))) |
| val = 2; |
| return val; |
| } |
| if (args2 == 0) |
| { |
| if (!self_promoting_args_p (args1)) |
| return 0; |
| if (TYPE_ACTUAL_ARG_TYPES (f2) |
| && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2))) |
| val = 2; |
| return val; |
| } |
| |
| /* Both types have argument lists: compare them and propagate results. */ |
| val1 = type_lists_compatible_p (args1, args2); |
| return val1 != 1 ? val1 : val; |
| } |
| |
| /* Check two lists of types for compatibility, |
| returning 0 for incompatible, 1 for compatible, |
| or 2 for compatible with warning. */ |
| |
| static int |
| type_lists_compatible_p (args1, args2) |
| tree args1, args2; |
| { |
| /* 1 if no need for warning yet, 2 if warning cause has been seen. */ |
| int val = 1; |
| int newval = 0; |
| |
| while (1) |
| { |
| if (args1 == 0 && args2 == 0) |
| return val; |
| /* If one list is shorter than the other, |
| they fail to match. */ |
| if (args1 == 0 || args2 == 0) |
| return 0; |
| /* A null pointer instead of a type |
| means there is supposed to be an argument |
| but nothing is specified about what type it has. |
| So match anything that self-promotes. */ |
| if (TREE_VALUE (args1) == 0) |
| { |
| if (! self_promoting_type_p (TREE_VALUE (args2))) |
| return 0; |
| } |
| else if (TREE_VALUE (args2) == 0) |
| { |
| if (! self_promoting_type_p (TREE_VALUE (args1))) |
| return 0; |
| } |
| else if (! (newval = comptypes (TREE_VALUE (args1), TREE_VALUE (args2)))) |
| { |
| /* Allow wait (union {union wait *u; int *i} *) |
| and wait (union wait *) to be compatible. */ |
| if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE |
| && (TYPE_NAME (TREE_VALUE (args1)) == 0 |
| || TYPE_TRANSPARENT_UNION (TREE_VALUE (args1))) |
| && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST |
| && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)), |
| TYPE_SIZE (TREE_VALUE (args2)))) |
| { |
| tree memb; |
| for (memb = TYPE_FIELDS (TREE_VALUE (args1)); |
| memb; memb = TREE_CHAIN (memb)) |
| if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2))) |
| break; |
| if (memb == 0) |
| return 0; |
| } |
| else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE |
| && (TYPE_NAME (TREE_VALUE (args2)) == 0 |
| || TYPE_TRANSPARENT_UNION (TREE_VALUE (args2))) |
| && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST |
| && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)), |
| TYPE_SIZE (TREE_VALUE (args1)))) |
| { |
| tree memb; |
| for (memb = TYPE_FIELDS (TREE_VALUE (args2)); |
| memb; memb = TREE_CHAIN (memb)) |
| if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1))) |
| break; |
| if (memb == 0) |
| return 0; |
| } |
| else |
| return 0; |
| } |
| |
| /* comptypes said ok, but record if it said to warn. */ |
| if (newval > val) |
| val = newval; |
| |
| args1 = TREE_CHAIN (args1); |
| args2 = TREE_CHAIN (args2); |
| } |
| } |
| |
| /* Return 1 if PARMS specifies a fixed number of parameters |
| and none of their types is affected by default promotions. */ |
| |
| int |
| self_promoting_args_p (parms) |
| tree parms; |
| { |
| register tree t; |
| for (t = parms; t; t = TREE_CHAIN (t)) |
| { |
| register tree type = TREE_VALUE (t); |
| |
| if (TREE_CHAIN (t) == 0 && type != void_type_node) |
| return 0; |
| |
| if (type == 0) |
| return 0; |
| |
| if (TYPE_MAIN_VARIANT (type) == float_type_node) |
| return 0; |
| |
| if (C_PROMOTING_INTEGER_TYPE_P (type)) |
| return 0; |
| } |
| return 1; |
| } |
| |
| /* Return 1 if TYPE is not affected by default promotions. */ |
| |
| static int |
| self_promoting_type_p (type) |
| tree type; |
| { |
| if (TYPE_MAIN_VARIANT (type) == float_type_node) |
| return 0; |
| |
| if (C_PROMOTING_INTEGER_TYPE_P (type)) |
| return 0; |
| |
| return 1; |
| } |
| |
| /* Return an unsigned type the same as TYPE in other respects. */ |
| |
| tree |
| unsigned_type (type) |
| tree type; |
| { |
| tree type1 = TYPE_MAIN_VARIANT (type); |
| if (type1 == signed_char_type_node || type1 == char_type_node) |
| return unsigned_char_type_node; |
| if (type1 == integer_type_node) |
| return unsigned_type_node; |
| if (type1 == short_integer_type_node) |
| return short_unsigned_type_node; |
| if (type1 == long_integer_type_node) |
| return long_unsigned_type_node; |
| if (type1 == long_long_integer_type_node) |
| return long_long_unsigned_type_node; |
| if (type1 == intDI_type_node) |
| return unsigned_intDI_type_node; |
| if (type1 == intSI_type_node) |
| return unsigned_intSI_type_node; |
| if (type1 == intHI_type_node) |
| return unsigned_intHI_type_node; |
| if (type1 == intQI_type_node) |
| return unsigned_intQI_type_node; |
| |
| return signed_or_unsigned_type (1, type); |
| } |
| |
| /* Return a signed type the same as TYPE in other respects. */ |
| |
| tree |
| signed_type (type) |
| tree type; |
| { |
| tree type1 = TYPE_MAIN_VARIANT (type); |
| if (type1 == unsigned_char_type_node || type1 == char_type_node) |
| return signed_char_type_node; |
| if (type1 == unsigned_type_node) |
| return integer_type_node; |
| if (type1 == short_unsigned_type_node) |
| return short_integer_type_node; |
| if (type1 == long_unsigned_type_node) |
| return long_integer_type_node; |
| if (type1 == long_long_unsigned_type_node) |
| return long_long_integer_type_node; |
| if (type1 == unsigned_intDI_type_node) |
| return intDI_type_node; |
| if (type1 == unsigned_intSI_type_node) |
| return intSI_type_node; |
| if (type1 == unsigned_intHI_type_node) |
| return intHI_type_node; |
| if (type1 == unsigned_intQI_type_node) |
| return intQI_type_node; |
| |
| return signed_or_unsigned_type (0, type); |
| } |
| |
| /* Return a type the same as TYPE except unsigned or |
| signed according to UNSIGNEDP. */ |
| |
| tree |
| signed_or_unsigned_type (unsignedp, type) |
| int unsignedp; |
| tree type; |
| { |
| if (! INTEGRAL_TYPE_P (type) |
| || TREE_UNSIGNED (type) == unsignedp) |
| return type; |
| if (TYPE_PRECISION (type) == TYPE_PRECISION (signed_char_type_node)) |
| return unsignedp ? unsigned_char_type_node : signed_char_type_node; |
| if (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)) |
| return unsignedp ? unsigned_type_node : integer_type_node; |
| if (TYPE_PRECISION (type) == TYPE_PRECISION (short_integer_type_node)) |
| return unsignedp ? short_unsigned_type_node : short_integer_type_node; |
| if (TYPE_PRECISION (type) == TYPE_PRECISION (long_integer_type_node)) |
| return unsignedp ? long_unsigned_type_node : long_integer_type_node; |
| if (TYPE_PRECISION (type) == TYPE_PRECISION (long_long_integer_type_node)) |
| return (unsignedp ? long_long_unsigned_type_node |
| : long_long_integer_type_node); |
| return type; |
| } |
| |
| /* Compute the value of the `sizeof' operator. */ |
| |
| tree |
| c_sizeof (type) |
| tree type; |
| { |
| enum tree_code code = TREE_CODE (type); |
| tree t; |
| |
| if (code == FUNCTION_TYPE) |
| { |
| if (pedantic || warn_pointer_arith) |
| pedwarn ("sizeof applied to a function type"); |
| return size_int (1); |
| } |
| if (code == VOID_TYPE) |
| { |
| if (pedantic || warn_pointer_arith) |
| pedwarn ("sizeof applied to a void type"); |
| return size_int (1); |
| } |
| if (code == ERROR_MARK) |
| return size_int (1); |
| if (TYPE_SIZE (type) == 0) |
| { |
| error ("sizeof applied to an incomplete type"); |
| return size_int (0); |
| } |
| |
| /* Convert in case a char is more than one unit. */ |
| t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), |
| size_int (TYPE_PRECISION (char_type_node))); |
| /* size_binop does not put the constant in range, so do it now. */ |
| if (TREE_CODE (t) == INTEGER_CST && force_fit_type (t, 0)) |
| TREE_CONSTANT_OVERFLOW (t) = TREE_OVERFLOW (t) = 1; |
| return t; |
| } |
| |
| tree |
| c_sizeof_nowarn (type) |
| tree type; |
| { |
| enum tree_code code = TREE_CODE (type); |
| tree t; |
| |
| if (code == FUNCTION_TYPE |
| || code == VOID_TYPE |
| || code == ERROR_MARK) |
| return size_int (1); |
| if (TYPE_SIZE (type) == 0) |
| return size_int (0); |
| |
| /* Convert in case a char is more than one unit. */ |
| t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), |
| size_int (TYPE_PRECISION (char_type_node))); |
| force_fit_type (t, 0); |
| return t; |
| } |
| |
| /* Compute the size to increment a pointer by. */ |
| |
| tree |
| c_size_in_bytes (type) |
| tree type; |
| { |
| enum tree_code code = TREE_CODE (type); |
| tree t; |
| |
| if (code == FUNCTION_TYPE) |
| return size_int (1); |
| if (code == VOID_TYPE) |
| return size_int (1); |
| if (code == ERROR_MARK) |
| return size_int (1); |
| if (TYPE_SIZE (type) == 0) |
| { |
| error ("arithmetic on pointer to an incomplete type"); |
| return size_int (1); |
| } |
| |
| /* Convert in case a char is more than one unit. */ |
| t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), |
| size_int (BITS_PER_UNIT)); |
| force_fit_type (t, 0); |
| return t; |
| } |
| |
| /* Implement the __alignof keyword: Return the minimum required |
| alignment of TYPE, measured in bytes. */ |
| |
| tree |
| c_alignof (type) |
| tree type; |
| { |
| enum tree_code code = TREE_CODE (type); |
| |
| if (code == FUNCTION_TYPE) |
| return size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT); |
| |
| if (code == VOID_TYPE || code == ERROR_MARK) |
| return size_int (1); |
| |
| return size_int (TYPE_ALIGN (type) / BITS_PER_UNIT); |
| } |
| |
| /* Implement the __alignof keyword: Return the minimum required |
| alignment of EXPR, measured in bytes. For VAR_DECL's and |
| FIELD_DECL's return DECL_ALIGN (which can be set from an |
| "aligned" __attribute__ specification). */ |
| |
| tree |
| c_alignof_expr (expr) |
| tree expr; |
| { |
| if (TREE_CODE (expr) == VAR_DECL) |
| return size_int (DECL_ALIGN (expr) / BITS_PER_UNIT); |
| |
| if (TREE_CODE (expr) == COMPONENT_REF |
| && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1))) |
| { |
| error ("`__alignof' applied to a bit-field"); |
| return size_int (1); |
| } |
| else if (TREE_CODE (expr) == COMPONENT_REF |
| && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL) |
| return size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT); |
| |
| if (TREE_CODE (expr) == INDIRECT_REF) |
| { |
| tree t = TREE_OPERAND (expr, 0); |
| tree best = t; |
| int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t))); |
| |
| while (TREE_CODE (t) == NOP_EXPR |
| && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE) |
| { |
| int thisalign; |
| |
| t = TREE_OPERAND (t, 0); |
| thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t))); |
| if (thisalign > bestalign) |
| best = t, bestalign = thisalign; |
| } |
| return c_alignof (TREE_TYPE (TREE_TYPE (best))); |
| } |
| else |
| return c_alignof (TREE_TYPE (expr)); |
| } |
| |
| /* Return either DECL or its known constant value (if it has one). */ |
| |
| static tree |
| decl_constant_value (decl) |
| tree decl; |
| { |
| if (/* Don't change a variable array bound or initial value to a constant |
| in a place where a variable is invalid. */ |
| current_function_decl != 0 |
| && ! pedantic |
| && ! TREE_THIS_VOLATILE (decl) |
| && TREE_READONLY (decl) && ! ITERATOR_P (decl) |
| && DECL_INITIAL (decl) != 0 |
| && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK |
| /* This is invalid if initial value is not constant. |
| If it has either a function call, a memory reference, |
| or a variable, then re-evaluating it could give different results. */ |
| && TREE_CONSTANT (DECL_INITIAL (decl)) |
| /* Check for cases where this is sub-optimal, even though valid. */ |
| && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR |
| && DECL_MODE (decl) != BLKmode) |
| return DECL_INITIAL (decl); |
| return decl; |
| } |
| |
| /* Perform default promotions for C data used in expressions. |
| Arrays and functions are converted to pointers; |
| enumeral types or short or char, to int. |
| In addition, manifest constants symbols are replaced by their values. */ |
| |
| tree |
| default_conversion (exp) |
| tree exp; |
| { |
| register tree type = TREE_TYPE (exp); |
| register enum tree_code code = TREE_CODE (type); |
| |
| /* Constants can be used directly unless they're not loadable. */ |
| if (TREE_CODE (exp) == CONST_DECL) |
| exp = DECL_INITIAL (exp); |
| |
| /* Replace a nonvolatile const static variable with its value unless |
| it is an array, in which case we must be sure that taking the |
| address of the array produces consistent results. */ |
| else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE) |
| { |
| exp = decl_constant_value (exp); |
| type = TREE_TYPE (exp); |
| } |
| |
| /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as |
| an lvalue. */ |
| /* Do not use STRIP_NOPS here! It will remove conversions from pointer |
| to integer and cause infinite recursion. */ |
| while (TREE_CODE (exp) == NON_LVALUE_EXPR |
| || (TREE_CODE (exp) == NOP_EXPR |
| && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp))) |
| exp = TREE_OPERAND (exp, 0); |
| |
| /* Normally convert enums to int, |
| but convert wide enums to something wider. */ |
| if (code == ENUMERAL_TYPE) |
| { |
| type = type_for_size (MAX (TYPE_PRECISION (type), |
| TYPE_PRECISION (integer_type_node)), |
| ((flag_traditional |
| || TYPE_PRECISION (type) >= TYPE_PRECISION (integer_type_node)) |
| && TREE_UNSIGNED (type))); |
| return convert (type, exp); |
| } |
| |
| if (TREE_CODE (exp) == COMPONENT_REF |
| && DECL_BIT_FIELD (TREE_OPERAND (exp, 1))) |
| { |
| tree width = DECL_SIZE (TREE_OPERAND (exp, 1)); |
| HOST_WIDE_INT low = TREE_INT_CST_LOW (width); |
| |
| /* If it's thinner than an int, promote it like a |
| C_PROMOTING_INTEGER_TYPE_P, otherwise leave it alone. */ |
| |
| if (low < TYPE_PRECISION (integer_type_node)) |
| { |
| if (flag_traditional && TREE_UNSIGNED (type)) |
| return convert (unsigned_type_node, exp); |
| else |
| return convert (integer_type_node, exp); |
| } |
| } |
| |
| if (C_PROMOTING_INTEGER_TYPE_P (type)) |
| { |
| /* Traditionally, unsignedness is preserved in default promotions. |
| Also preserve unsignedness if not really getting any wider. */ |
| if (TREE_UNSIGNED (type) |
| && (flag_traditional |
| || TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))) |
| return convert (unsigned_type_node, exp); |
| return convert (integer_type_node, exp); |
| } |
| if (flag_traditional && !flag_allow_single_precision |
| && TYPE_MAIN_VARIANT (type) == float_type_node) |
| return convert (double_type_node, exp); |
| if (code == VOID_TYPE) |
| { |
| error ("void value not ignored as it ought to be"); |
| return error_mark_node; |
| } |
| if (code == FUNCTION_TYPE) |
| { |
| return build_unary_op (ADDR_EXPR, exp, 0); |
| } |
| if (code == ARRAY_TYPE) |
| { |
| register tree adr; |
| tree restype = TREE_TYPE (type); |
| tree ptrtype; |
| int constp = 0; |
| int volatilep = 0; |
| |
| if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r' |
| || TREE_CODE_CLASS (TREE_CODE (exp)) == 'd') |
| { |
| constp = TREE_READONLY (exp); |
| volatilep = TREE_THIS_VOLATILE (exp); |
| } |
| |
| if (TYPE_READONLY (type) || TYPE_VOLATILE (type) |
| || constp || volatilep) |
| restype = c_build_type_variant (restype, |
| TYPE_READONLY (type) || constp, |
| TYPE_VOLATILE (type) || volatilep); |
| |
| if (TREE_CODE (exp) == INDIRECT_REF) |
| return convert (TYPE_POINTER_TO (restype), |
| TREE_OPERAND (exp, 0)); |
| |
| if (TREE_CODE (exp) == COMPOUND_EXPR) |
| { |
| tree op1 = default_conversion (TREE_OPERAND (exp, 1)); |
| return build (COMPOUND_EXPR, TREE_TYPE (op1), |
| TREE_OPERAND (exp, 0), op1); |
| } |
| |
| if (! lvalue_p (exp) |
| && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp))) |
| { |
| error ("invalid use of non-lvalue array"); |
| return error_mark_node; |
| } |
| |
| ptrtype = build_pointer_type (restype); |
| |
| if (TREE_CODE (exp) == VAR_DECL) |
| { |
| /* ??? This is not really quite correct |
| in that the type of the operand of ADDR_EXPR |
| is not the target type of the type of the ADDR_EXPR itself. |
| Question is, can this lossage be avoided? */ |
| adr = build1 (ADDR_EXPR, ptrtype, exp); |
| if (mark_addressable (exp) == 0) |
| return error_mark_node; |
| TREE_CONSTANT (adr) = staticp (exp); |
| TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */ |
| return adr; |
| } |
| /* This way is better for a COMPONENT_REF since it can |
| simplify the offset for a component. */ |
| adr = build_unary_op (ADDR_EXPR, exp, 1); |
| return convert (ptrtype, adr); |
| } |
| return exp; |
| } |
| |
| /* Look up component name in the structure type definition. |
| |
| If this component name is found indirectly within an anonymous union, |
| store in *INDIRECT the component which directly contains |
| that anonymous union. Otherwise, set *INDIRECT to 0. */ |
| |
| static tree |
| lookup_field (type, component, indirect) |
| tree type, component; |
| tree *indirect; |
| { |
| tree field; |
| |
| /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers |
| to the field elements. Use a binary search on this array to quickly |
| find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC |
| will always be set for structures which have many elements. */ |
| |
| if (TYPE_LANG_SPECIFIC (type)) |
| { |
| int bot, top, half; |
| tree *field_array = &TYPE_LANG_SPECIFIC (type)->elts[0]; |
| |
| field = TYPE_FIELDS (type); |
| bot = 0; |
| top = TYPE_LANG_SPECIFIC (type)->len; |
| while (top - bot > 1) |
| { |
| half = (top - bot + 1) >> 1; |
| field = field_array[bot+half]; |
| |
| if (DECL_NAME (field) == NULL_TREE) |
| { |
| /* Step through all anon unions in linear fashion. */ |
| while (DECL_NAME (field_array[bot]) == NULL_TREE) |
| { |
| tree anon = 0, junk; |
| |
| field = field_array[bot++]; |
| if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE |
| || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE) |
| anon = lookup_field (TREE_TYPE (field), component, &junk); |
| |
| if (anon != NULL_TREE) |
| { |
| *indirect = field; |
| return anon; |
| } |
| } |
| |
| /* Entire record is only anon unions. */ |
| if (bot > top) |
| return NULL_TREE; |
| |
| /* Restart the binary search, with new lower bound. */ |
| continue; |
| } |
| |
| if (DECL_NAME (field) == component) |
| break; |
| if (DECL_NAME (field) < component) |
| bot += half; |
| else |
| top = bot + half; |
| } |
| |
| if (DECL_NAME (field_array[bot]) == component) |
| field = field_array[bot]; |
| else if (DECL_NAME (field) != component) |
| field = 0; |
| } |
| else |
| { |
| for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) |
| { |
| if (DECL_NAME (field) == NULL_TREE) |
| { |
| tree junk; |
| tree anon = 0; |
| |
| if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE |
| || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE) |
| anon = lookup_field (TREE_TYPE (field), component, &junk); |
| |
| if (anon != NULL_TREE) |
| { |
| *indirect = field; |
| return anon; |
| } |
| } |
| |
| if (DECL_NAME (field) == component) |
| break; |
| } |
| } |
| |
| *indirect = NULL_TREE; |
| return field; |
| } |
| |
| /* Make an expression to refer to the COMPONENT field of |
| structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */ |
| |
| tree |
| build_component_ref (datum, component) |
| tree datum, component; |
| { |
| register tree type = TREE_TYPE (datum); |
| register enum tree_code code = TREE_CODE (type); |
| register tree field = NULL; |
| register tree ref; |
| |
| /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it |
| unless we are not to support things not strictly ANSI. */ |
| switch (TREE_CODE (datum)) |
| { |
| case COMPOUND_EXPR: |
| { |
| tree value = build_component_ref (TREE_OPERAND (datum, 1), component); |
| return build (COMPOUND_EXPR, TREE_TYPE (value), |
| TREE_OPERAND (datum, 0), value); |
| } |
| case COND_EXPR: |
| return build_conditional_expr |
| (TREE_OPERAND (datum, 0), |
| build_component_ref (TREE_OPERAND (datum, 1), component), |
| build_component_ref (TREE_OPERAND (datum, 2), component)); |
| } |
| |
| /* See if there is a field or component with name COMPONENT. */ |
| |
| if (code == RECORD_TYPE || code == UNION_TYPE) |
| { |
| tree indirect = 0; |
| |
| if (TYPE_SIZE (type) == 0) |
| { |
| incomplete_type_error (NULL_TREE, type); |
| return error_mark_node; |
| } |
| |
| field = lookup_field (type, component, &indirect); |
| |
| if (!field) |
| { |
| error (code == RECORD_TYPE |
| ? "structure has no member named `%s'" |
| : "union has no member named `%s'", |
| IDENTIFIER_POINTER (component)); |
| return error_mark_node; |
| } |
| if (TREE_TYPE (field) == error_mark_node) |
| return error_mark_node; |
| |
| /* If FIELD was found buried within an anonymous union, |
| make one COMPONENT_REF to get that anonymous union, |
| then fall thru to make a second COMPONENT_REF to get FIELD. */ |
| if (indirect != 0) |
| { |
| ref = build (COMPONENT_REF, TREE_TYPE (indirect), datum, indirect); |
| if (TREE_READONLY (datum) || TREE_READONLY (indirect)) |
| TREE_READONLY (ref) = 1; |
| if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (indirect)) |
| TREE_THIS_VOLATILE (ref) = 1; |
| datum = ref; |
| } |
| |
| ref = build (COMPONENT_REF, TREE_TYPE (field), datum, field); |
| |
| if (TREE_READONLY (datum) || TREE_READONLY (field)) |
| TREE_READONLY (ref) = 1; |
| if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (field)) |
| TREE_THIS_VOLATILE (ref) = 1; |
| |
| return ref; |
| } |
| else if (code != ERROR_MARK) |
| error ("request for member `%s' in something not a structure or union", |
| IDENTIFIER_POINTER (component)); |
| |
| return error_mark_node; |
| } |
| |
| /* Given an expression PTR for a pointer, return an expression |
| for the value pointed to. |
| ERRORSTRING is the name of the operator to appear in error messages. */ |
| |
| tree |
| build_indirect_ref (ptr, errorstring) |
| tree ptr; |
| char *errorstring; |
| { |
| register tree pointer = default_conversion (ptr); |
| register tree type = TREE_TYPE (pointer); |
| |
| if (TREE_CODE (type) == POINTER_TYPE) |
| { |
| if (TREE_CODE (pointer) == ADDR_EXPR |
| && !flag_volatile |
| && (TREE_TYPE (TREE_OPERAND (pointer, 0)) |
| == TREE_TYPE (type))) |
| return TREE_OPERAND (pointer, 0); |
| else |
| { |
| tree t = TREE_TYPE (type); |
| register tree ref = build1 (INDIRECT_REF, |
| TYPE_MAIN_VARIANT (t), pointer); |
| |
| if (TYPE_SIZE (t) == 0 && TREE_CODE (t) != ARRAY_TYPE) |
| { |
| error ("dereferencing pointer to incomplete type"); |
| return error_mark_node; |
| } |
| if (TREE_CODE (t) == VOID_TYPE && skip_evaluation == 0) |
| warning ("dereferencing `void *' pointer"); |
| |
| /* We *must* set TREE_READONLY when dereferencing a pointer to const, |
| so that we get the proper error message if the result is used |
| to assign to. Also, &* is supposed to be a no-op. |
| And ANSI C seems to specify that the type of the result |
| should be the const type. */ |
| /* A de-reference of a pointer to const is not a const. It is valid |
| to change it via some other pointer. */ |
| TREE_READONLY (ref) = TYPE_READONLY (t); |
| TREE_SIDE_EFFECTS (ref) |
| = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer) || flag_volatile; |
| TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t); |
| return ref; |
| } |
| } |
| else if (TREE_CODE (pointer) != ERROR_MARK) |
| error ("invalid type argument of `%s'", errorstring); |
| return error_mark_node; |
| } |
| |
| /* This handles expressions of the form "a[i]", which denotes |
| an array reference. |
| |
| This is logically equivalent in C to *(a+i), but we may do it differently. |
| If A is a variable or a member, we generate a primitive ARRAY_REF. |
| This avoids forcing the array out of registers, and can work on |
| arrays that are not lvalues (for example, members of structures returned |
| by functions). */ |
| |
| tree |
| build_array_ref (array, index) |
| tree array, index; |
| { |
| if (index == 0) |
| { |
| error ("subscript missing in array reference"); |
| return error_mark_node; |
| } |
| |
| if (TREE_TYPE (array) == error_mark_node |
| || TREE_TYPE (index) == error_mark_node) |
| return error_mark_node; |
| |
| if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE |
| && TREE_CODE (array) != INDIRECT_REF) |
| { |
| tree rval, type; |
| |
| /* Subscripting with type char is likely to lose |
| on a machine where chars are signed. |
| So warn on any machine, but optionally. |
| Don't warn for unsigned char since that type is safe. |
| Don't warn for signed char because anyone who uses that |
| must have done so deliberately. */ |
| if (warn_char_subscripts |
| && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node) |
| warning ("array subscript has type `char'"); |
| |
| /* Apply default promotions *after* noticing character types. */ |
| index = default_conversion (index); |
| |
| /* Require integer *after* promotion, for sake of enums. */ |
| if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE) |
| { |
| error ("array subscript is not an integer"); |
| return error_mark_node; |
| } |
| |
| /* An array that is indexed by a non-constant |
| cannot be stored in a register; we must be able to do |
| address arithmetic on its address. |
| Likewise an array of elements of variable size. */ |
| if (TREE_CODE (index) != INTEGER_CST |
| || (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))) != 0 |
| && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST)) |
| { |
| if (mark_addressable (array) == 0) |
| return error_mark_node; |
| } |
| /* An array that is indexed by a constant value which is not within |
| the array bounds cannot be stored in a register either; because we |
| would get a crash in store_bit_field/extract_bit_field when trying |
| to access a non-existent part of the register. */ |
| if (TREE_CODE (index) == INTEGER_CST |
| && TYPE_VALUES (TREE_TYPE (array)) |
| && ! int_fits_type_p (index, TYPE_VALUES (TREE_TYPE (array)))) |
| { |
| if (mark_addressable (array) == 0) |
| return error_mark_node; |
| } |
| |
| if (pedantic && !lvalue_p (array)) |
| { |
| if (DECL_REGISTER (array)) |
| pedwarn ("ANSI C forbids subscripting `register' array"); |
| else |
| pedwarn ("ANSI C forbids subscripting non-lvalue array"); |
| } |
| |
| if (pedantic) |
| { |
| tree foo = array; |
| while (TREE_CODE (foo) == COMPONENT_REF) |
| foo = TREE_OPERAND (foo, 0); |
| if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo)) |
| pedwarn ("ANSI C forbids subscripting non-lvalue array"); |
| } |
| |
| type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array))); |
| rval = build (ARRAY_REF, type, array, index); |
| /* Array ref is const/volatile if the array elements are |
| or if the array is. */ |
| TREE_READONLY (rval) |
| |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array))) |
| | TREE_READONLY (array)); |
| TREE_SIDE_EFFECTS (rval) |
| |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) |
| | TREE_SIDE_EFFECTS (array)); |
| TREE_THIS_VOLATILE (rval) |
| |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) |
| /* This was added by rms on 16 Nov 91. |
| It fixes vol struct foo *a; a->elts[1] |
| in an inline function. |
| Hope it doesn't break something else. */ |
| | TREE_THIS_VOLATILE (array)); |
| return require_complete_type (fold (rval)); |
| } |
| |
| { |
| tree ar = default_conversion (array); |
| tree ind = default_conversion (index); |
| |
| /* Do the same warning check as above, but only on the part that's |
| syntactically the index and only if it is also semantically |
| the index. */ |
| if (warn_char_subscripts |
| && TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE |
| && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node) |
| warning ("subscript has type `char'"); |
| |
| /* Put the integer in IND to simplify error checking. */ |
| if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE) |
| { |
| tree temp = ar; |
| ar = ind; |
| ind = temp; |
| } |
| |
| if (ar == error_mark_node) |
| return ar; |
| |
| if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE |
| || TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) == FUNCTION_TYPE) |
| { |
| error ("subscripted value is neither array nor pointer"); |
| return error_mark_node; |
| } |
| if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE) |
| { |
| error ("array subscript is not an integer"); |
| return error_mark_node; |
| } |
| |
| return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0), |
| "array indexing"); |
| } |
| } |
| |
| /* Build a function call to function FUNCTION with parameters PARAMS. |
| PARAMS is a list--a chain of TREE_LIST nodes--in which the |
| TREE_VALUE of each node is a parameter-expression. |
| FUNCTION's data type may be a function type or a pointer-to-function. */ |
| |
| tree |
| build_function_call (function, params) |
| tree function, params; |
| { |
| register tree fntype, fundecl = 0; |
| register tree coerced_params; |
| tree name = NULL_TREE, assembler_name = NULL_TREE; |
| |
| /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ |
| STRIP_TYPE_NOPS (function); |
| |
| /* Convert anything with function type to a pointer-to-function. */ |
| if (TREE_CODE (function) == FUNCTION_DECL) |
| { |
| name = DECL_NAME (function); |
| assembler_name = DECL_ASSEMBLER_NAME (function); |
| |
| /* Differs from default_conversion by not setting TREE_ADDRESSABLE |
| (because calling an inline function does not mean the function |
| needs to be separately compiled). */ |
| fntype = build_type_variant (TREE_TYPE (function), |
| TREE_READONLY (function), |
| TREE_THIS_VOLATILE (function)); |
| fundecl = function; |
| function = build1 (ADDR_EXPR, build_pointer_type (fntype), function); |
| } |
| else |
| function = default_conversion (function); |
| |
| fntype = TREE_TYPE (function); |
| |
| if (TREE_CODE (fntype) == ERROR_MARK) |
| return error_mark_node; |
| |
| if (!(TREE_CODE (fntype) == POINTER_TYPE |
| && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)) |
| { |
| error ("called object is not a function"); |
| return error_mark_node; |
| } |
| |
| /* fntype now gets the type of function pointed to. */ |
| fntype = TREE_TYPE (fntype); |
| |
| /* Convert the parameters to the types declared in the |
| function prototype, or apply default promotions. */ |
| |
| coerced_params |
| = convert_arguments (TYPE_ARG_TYPES (fntype), params, name, fundecl); |
| |
| /* Check for errors in format strings. */ |
| |
| if (warn_format && (name || assembler_name)) |
| check_function_format (name, assembler_name, coerced_params); |
| |
| /* Recognize certain built-in functions so we can make tree-codes |
| other than CALL_EXPR. We do this when it enables fold-const.c |
| to do something useful. */ |
| |
| if (TREE_CODE (function) == ADDR_EXPR |
| && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL |
| && DECL_BUILT_IN (TREE_OPERAND (function, 0))) |
| switch (DECL_FUNCTION_CODE (TREE_OPERAND (function, 0))) |
| { |
| case BUILT_IN_ABS: |
| case BUILT_IN_LABS: |
| case BUILT_IN_FABS: |
| if (coerced_params == 0) |
| return integer_zero_node; |
| return build_unary_op (ABS_EXPR, TREE_VALUE (coerced_params), 0); |
| } |
| |
| { |
| register tree result |
| = build (CALL_EXPR, TREE_TYPE (fntype), |
| function, coerced_params, NULL_TREE); |
| |
| TREE_SIDE_EFFECTS (result) = 1; |
| if (TREE_TYPE (result) == void_type_node) |
| return result; |
| return require_complete_type (result); |
| } |
| } |
| |
| /* Convert the argument expressions in the list VALUES |
| to the types in the list TYPELIST. The result is a list of converted |
| argument expressions. |
| |
| If TYPELIST is exhausted, or when an element has NULL as its type, |
| perform the default conversions. |
| |
| PARMLIST is the chain of parm decls for the function being called. |
| It may be 0, if that info is not available. |
| It is used only for generating error messages. |
| |
| NAME is an IDENTIFIER_NODE or 0. It is used only for error messages. |
| |
| This is also where warnings about wrong number of args are generated. |
| |
| Both VALUES and the returned value are chains of TREE_LIST nodes |
| with the elements of the list in the TREE_VALUE slots of those nodes. */ |
| |
| static tree |
| convert_arguments (typelist, values, name, fundecl) |
| tree typelist, values, name, fundecl; |
| { |
| register tree typetail, valtail; |
| register tree result = NULL; |
| int parmnum; |
| |
| /* Scan the given expressions and types, producing individual |
| converted arguments and pushing them on RESULT in reverse order. */ |
| |
| for (valtail = values, typetail = typelist, parmnum = 0; |
| valtail; |
| valtail = TREE_CHAIN (valtail), parmnum++) |
| { |
| register tree type = typetail ? TREE_VALUE (typetail) : 0; |
| register tree val = TREE_VALUE (valtail); |
| |
| if (type == void_type_node) |
| { |
| if (name) |
| error ("too many arguments to function `%s'", |
| IDENTIFIER_POINTER (name)); |
| else |
| error ("too many arguments to function"); |
| break; |
| } |
| |
| /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */ |
| /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0 |
| to convert automatically to a pointer. */ |
| if (TREE_CODE (val) == NON_LVALUE_EXPR) |
| val = TREE_OPERAND (val, 0); |
| |
| if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE |
| || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE) |
| val = default_conversion (val); |
| |
| val = require_complete_type (val); |
| |
| if (type != 0) |
| { |
| /* Formal parm type is specified by a function prototype. */ |
| tree parmval; |
| |
| if (TYPE_SIZE (type) == 0) |
| { |
| error ("type of formal parameter %d is incomplete", parmnum + 1); |
| parmval = val; |
| } |
| else |
| { |
| /* Optionally warn about conversions that |
| differ from the default conversions. */ |
| if (warn_conversion) |
| { |
| int formal_prec = TYPE_PRECISION (type); |
| |
| if (INTEGRAL_TYPE_P (type) |
| && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) |
| warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1); |
| else if (TREE_CODE (type) == COMPLEX_TYPE |
| && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) |
| warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1); |
| else if (TREE_CODE (type) == REAL_TYPE |
| && INTEGRAL_TYPE_P (TREE_TYPE (val))) |
| warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1); |
| else if (TREE_CODE (type) == REAL_TYPE |
| && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE) |
| warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1); |
| /* ??? At some point, messages should be written about |
| conversions between complex types, but that's too messy |
| to do now. */ |
| else if (TREE_CODE (type) == REAL_TYPE |
| && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) |
| { |
| /* Warn if any argument is passed as `float', |
| since without a prototype it would be `double'. */ |
| if (formal_prec == TYPE_PRECISION (float_type_node)) |
| warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1); |
| } |
| /* Detect integer changing in width or signedness. */ |
| else if (INTEGRAL_TYPE_P (type) |
| && INTEGRAL_TYPE_P (TREE_TYPE (val))) |
| { |
| tree would_have_been = default_conversion (val); |
| tree type1 = TREE_TYPE (would_have_been); |
| |
| if (TREE_CODE (type) == ENUMERAL_TYPE |
| && type == TREE_TYPE (val)) |
| /* No warning if function asks for enum |
| and the actual arg is that enum type. */ |
| ; |
| else if (formal_prec != TYPE_PRECISION (type1)) |
| warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1); |
| else if (TREE_UNSIGNED (type) == TREE_UNSIGNED (type1)) |
| ; |
| /* Don't complain if the formal parameter type |
| is an enum, because we can't tell now whether |
| the value was an enum--even the same enum. */ |
| else if (TREE_CODE (type) == ENUMERAL_TYPE) |
| ; |
| else if (TREE_CODE (val) == INTEGER_CST |
| && int_fits_type_p (val, type)) |
| /* Change in signedness doesn't matter |
| if a constant value is unaffected. */ |
| ; |
| /* Likewise for a constant in a NOP_EXPR. */ |
| else if (TREE_CODE (val) == NOP_EXPR |
| && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST |
| && int_fits_type_p (TREE_OPERAND (val, 0), type)) |
| ; |
| #if 0 /* We never get such tree structure here. */ |
| else if (TREE_CODE (TREE_TYPE (val)) == ENUMERAL_TYPE |
| && int_fits_type_p (TYPE_MIN_VALUE (TREE_TYPE (val)), type) |
| && int_fits_type_p (TYPE_MAX_VALUE (TREE_TYPE (val)), type)) |
| /* Change in signedness doesn't matter |
| if an enum value is unaffected. */ |
| ; |
| #endif |
| /* If the value is extended from a narrower |
| unsigned type, it doesn't matter whether we |
| pass it as signed or unsigned; the value |
| certainly is the same either way. */ |
| else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type) |
| && TREE_UNSIGNED (TREE_TYPE (val))) |
| ; |
| else if (TREE_UNSIGNED (type)) |
| warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1); |
| else |
| warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1); |
| } |
| } |
| |
| parmval = convert_for_assignment (type, val, |
| (char *) 0, /* arg passing */ |
| fundecl, name, parmnum + 1); |
| |
| #ifdef PROMOTE_PROTOTYPES |
| if ((TREE_CODE (type) == INTEGER_TYPE |
| || TREE_CODE (type) == ENUMERAL_TYPE) |
| && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) |
| parmval = default_conversion (parmval); |
| #endif |
| } |
| result = tree_cons (NULL_TREE, parmval, result); |
| } |
| else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE |
| && (TYPE_PRECISION (TREE_TYPE (val)) |
| < TYPE_PRECISION (double_type_node))) |
| /* Convert `float' to `double'. */ |
| result = tree_cons (NULL_TREE, convert (double_type_node, val), result); |
| else |
| /* Convert `short' and `char' to full-size `int'. */ |
| result = tree_cons (NULL_TREE, default_conversion (val), result); |
| |
| if (typetail) |
| typetail = TREE_CHAIN (typetail); |
| } |
| |
| if (typetail != 0 && TREE_VALUE (typetail) != void_type_node) |
| { |
| if (name) |
| error ("too few arguments to function `%s'", |
| IDENTIFIER_POINTER (name)); |
| else |
| error ("too few arguments to function"); |
| } |
| |
| return nreverse (result); |
| } |
| |
| /* This is the entry point used by the parser |
| for binary operators in the input. |
| In addition to constructing the expression, |
| we check for operands that were written with other binary operators |
| in a way that is likely to confuse the user. */ |
| |
| tree |
| parser_build_binary_op (code, arg1, arg2) |
| enum tree_code code; |
| tree arg1, arg2; |
| { |
| tree result = build_binary_op (code, arg1, arg2, 1); |
| |
| char class; |
| char class1 = TREE_CODE_CLASS (TREE_CODE (arg1)); |
| char class2 = TREE_CODE_CLASS (TREE_CODE (arg2)); |
| enum tree_code code1 = ERROR_MARK; |
| enum tree_code code2 = ERROR_MARK; |
| |
| if (class1 == 'e' || class1 == '1' |
| || class1 == '2' || class1 == '<') |
| code1 = C_EXP_ORIGINAL_CODE (arg1); |
| if (class2 == 'e' || class2 == '1' |
| || class2 == '2' || class2 == '<') |
| code2 = C_EXP_ORIGINAL_CODE (arg2); |
| |
| /* Check for cases such as x+y<<z which users are likely |
| to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE |
| is cleared to prevent these warnings. */ |
| if (warn_parentheses) |
| { |
| if (code == LSHIFT_EXPR || code == RSHIFT_EXPR) |
| { |
| if (code1 == PLUS_EXPR || code1 == MINUS_EXPR |
| || code2 == PLUS_EXPR || code2 == MINUS_EXPR) |
| warning ("suggest parentheses around + or - inside shift"); |
| } |
| |
| if (code == TRUTH_ORIF_EXPR) |
| { |
| if (code1 == TRUTH_ANDIF_EXPR |
| || code2 == TRUTH_ANDIF_EXPR) |
| warning ("suggest parentheses around && within ||"); |
| } |
| |
| if (code == BIT_IOR_EXPR) |
| { |
| if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR |
| || code1 == PLUS_EXPR || code1 == MINUS_EXPR |
| || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR |
| || code2 == PLUS_EXPR || code2 == MINUS_EXPR) |
| warning ("suggest parentheses around arithmetic in operand of |"); |
| /* Check cases like x|y==z */ |
| if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<') |
| warning ("suggest parentheses around comparison in operand of |"); |
| } |
| |
| if (code == BIT_XOR_EXPR) |
| { |
| if (code1 == BIT_AND_EXPR |
| || code1 == PLUS_EXPR || code1 == MINUS_EXPR |
| || code2 == BIT_AND_EXPR |
| || code2 == PLUS_EXPR || code2 == MINUS_EXPR) |
| warning ("suggest parentheses around arithmetic in operand of ^"); |
| /* Check cases like x^y==z */ |
| if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<') |
| warning ("suggest parentheses around comparison in operand of ^"); |
| } |
| |
| if (code == BIT_AND_EXPR) |
| { |
| if (code1 == PLUS_EXPR || code1 == MINUS_EXPR |
| || code2 == PLUS_EXPR || code2 == MINUS_EXPR) |
| warning ("suggest parentheses around + or - in operand of &"); |
| /* Check cases like x&y==z */ |
| if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<') |
| warning ("suggest parentheses around comparison in operand of &"); |
| } |
| } |
| |
| /* Similarly, check for cases like 1<=i<=10 that are probably errors. */ |
| if (TREE_CODE_CLASS (code) == '<' && extra_warnings |
| && (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')) |
| warning ("comparisons like X<=Y<=Z do not have their mathematical meaning"); |
| |
| unsigned_conversion_warning (result, arg1); |
| unsigned_conversion_warning (result, arg2); |
| overflow_warning (result); |
| |
| class = TREE_CODE_CLASS (TREE_CODE (result)); |
| |
| /* Record the code that was specified in the source, |
| for the sake of warnings about confusing nesting. */ |
| if (class == 'e' || class == '1' |
| || class == '2' || class == '<') |
| C_SET_EXP_ORIGINAL_CODE (result, code); |
| else |
| { |
| int flag = TREE_CONSTANT (result); |
| /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR |
| so that convert_for_assignment wouldn't strip it. |
| That way, we got warnings for things like p = (1 - 1). |
| But it turns out we should not get those warnings. */ |
| result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result); |
| C_SET_EXP_ORIGINAL_CODE (result, code); |
| TREE_CONSTANT (result) = flag; |
| } |
| |
| return result; |
| } |
| |
| /* Build a binary-operation expression without default conversions. |
| CODE is the kind of expression to build. |
| This function differs from `build' in several ways: |
| the data type of the result is computed and recorded in it, |
| warnings are generated if arg data types are invalid, |
| special handling for addition and subtraction of pointers is known, |
| and some optimization is done (operations on narrow ints |
| are done in the narrower type when that gives the same result). |
| Constant folding is also done before the result is returned. |
| |
| Note that the operands will never have enumeral types, or function |
| or array types, because either they will have the default conversions |
| performed or they have both just been converted to some other type in which |
| the arithmetic is to be done. */ |
| |
| tree |
| build_binary_op (code, orig_op0, orig_op1, convert_p) |
| enum tree_code code; |
| tree orig_op0, orig_op1; |
| int convert_p; |
| { |
| tree type0, type1; |
| register enum tree_code code0, code1; |
| tree op0, op1; |
| |
| /* Expression code to give to the expression when it is built. |
| Normally this is CODE, which is what the caller asked for, |
| but in some special cases we change it. */ |
| register enum tree_code resultcode = code; |
| |
| /* Data type in which the computation is to be performed. |
| In the simplest cases this is the common type of the arguments. */ |
| register tree result_type = NULL; |
| |
| /* Nonzero means operands have already been type-converted |
| in whatever way is necessary. |
| Zero means they need to be converted to RESULT_TYPE. */ |
| int converted = 0; |
| |
| /* Nonzero means create the expression with this type, rather than |
| RESULT_TYPE. */ |
| tree build_type = 0; |
| |
| /* Nonzero means after finally constructing the expression |
| convert it to this type. */ |
| tree final_type = 0; |
| |
| /* Nonzero if this is an operation like MIN or MAX which can |
| safely be computed in short if both args are promoted shorts. |
| Also implies COMMON. |
| -1 indicates a bitwise operation; this makes a difference |
| in the exact conditions for when it is safe to do the operation |
| in a narrower mode. */ |
| int shorten = 0; |
| |
| /* Nonzero if this is a comparison operation; |
| if both args are promoted shorts, compare the original shorts. |
| Also implies COMMON. */ |
| int short_compare = 0; |
| |
| /* Nonzero if this is a right-shift operation, which can be computed on the |
| original short and then promoted if the operand is a promoted short. */ |
| int short_shift = 0; |
| |
| /* Nonzero means set RESULT_TYPE to the common type of the args. */ |
| int common = 0; |
| |
| if (convert_p) |
| { |
| op0 = default_conversion (orig_op0); |
| op1 = default_conversion (orig_op1); |
| } |
| else |
| { |
| op0 = orig_op0; |
| op1 = orig_op1; |
| } |
| |
| type0 = TREE_TYPE (op0); |
| type1 = TREE_TYPE (op1); |
| |
| /* The expression codes of the data types of the arguments tell us |
| whether the arguments are integers, floating, pointers, etc. */ |
| code0 = TREE_CODE (type0); |
| code1 = TREE_CODE (type1); |
| |
| /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ |
| STRIP_TYPE_NOPS (op0); |
| STRIP_TYPE_NOPS (op1); |
| |
| /* If an error was already reported for one of the arguments, |
| avoid reporting another error. */ |
| |
| if (code0 == ERROR_MARK || code1 == ERROR_MARK) |
| return error_mark_node; |
| |
| switch (code) |
| { |
| case PLUS_EXPR: |
| /* Handle the pointer + int case. */ |
| if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) |
| return pointer_int_sum (PLUS_EXPR, op0, op1); |
| else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE) |
| return pointer_int_sum (PLUS_EXPR, op1, op0); |
| else |
| common = 1; |
| break; |
| |
| case MINUS_EXPR: |
| /* Subtraction of two similar pointers. |
| We must subtract them as integers, then divide by object size. */ |
| if (code0 == POINTER_TYPE && code1 == POINTER_TYPE |
| && comp_target_types (type0, type1)) |
| return pointer_diff (op0, op1); |
| /* Handle pointer minus int. Just like pointer plus int. */ |
| else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) |
| return pointer_int_sum (MINUS_EXPR, op0, op1); |
| else |
| common = 1; |
| break; |
| |
| case MULT_EXPR: |
| common = 1; |
| break; |
| |
| case TRUNC_DIV_EXPR: |
| case CEIL_DIV_EXPR: |
| case FLOOR_DIV_EXPR: |
| case ROUND_DIV_EXPR: |
| case EXACT_DIV_EXPR: |
| if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE |
| || code0 == COMPLEX_TYPE) |
| && (code1 == INTEGER_TYPE || code1 == REAL_TYPE |
| || code1 == COMPLEX_TYPE)) |
| { |
| if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)) |
| resultcode = RDIV_EXPR; |
| else |
| { |
| /* Although it would be tempting to shorten always here, that |
| loses on some targets, since the modulo instruction is |
| undefined if the quotient can't be represented in the |
| computation mode. We shorten only if unsigned or if |
| dividing by something we know != -1. */ |
| shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0)) |
| || (TREE_CODE (op1) == INTEGER_CST |
| && (TREE_INT_CST_LOW (op1) != -1 |
| || TREE_INT_CST_HIGH (op1) != -1))); |
| } |
| common = 1; |
| } |
| break; |
| |
| case BIT_AND_EXPR: |
| case BIT_ANDTC_EXPR: |
| case BIT_IOR_EXPR: |
| case BIT_XOR_EXPR: |
| if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) |
| shorten = -1; |
| /* If one operand is a constant, and the other is a short type |
| that has been converted to an int, |
| really do the work in the short type and then convert the |
| result to int. If we are lucky, the constant will be 0 or 1 |
| in the short type, making the entire operation go away. */ |
| if (TREE_CODE (op0) == INTEGER_CST |
| && TREE_CODE (op1) == NOP_EXPR |
| && TYPE_PRECISION (type1) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0))) |
| && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0)))) |
| { |
| final_type = result_type; |
| op1 = TREE_OPERAND (op1, 0); |
| result_type = TREE_TYPE (op1); |
| } |
| if (TREE_CODE (op1) == INTEGER_CST |
| && TREE_CODE (op0) == NOP_EXPR |
| && TYPE_PRECISION (type0) > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0))) |
| && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0)))) |
| { |
| final_type = result_type; |
| op0 = TREE_OPERAND (op0, 0); |
| result_type = TREE_TYPE (op0); |
| } |
| break; |
| |
| case TRUNC_MOD_EXPR: |
| case FLOOR_MOD_EXPR: |
| if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) |
| { |
| /* Although it would be tempting to shorten always here, that loses |
| on some targets, since the modulo instruction is undefined if the |
| quotient can't be represented in the computation mode. We shorten |
| only if unsigned or if dividing by something we know != -1. */ |
| shorten = (TREE_UNSIGNED (TREE_TYPE (orig_op0)) |
| || (TREE_CODE (op1) == INTEGER_CST |
| && (TREE_INT_CST_LOW (op1) != -1 |
| || TREE_INT_CST_HIGH (op1) != -1))); |
| common = 1; |
| } |
| break; |
| |
| case TRUTH_ANDIF_EXPR: |
| case TRUTH_ORIF_EXPR: |
| case TRUTH_AND_EXPR: |
| case TRUTH_OR_EXPR: |
| case TRUTH_XOR_EXPR: |
| if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE |
| || code0 == REAL_TYPE || code0 == COMPLEX_TYPE) |
| && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE |
| || code1 == REAL_TYPE || code1 == COMPLEX_TYPE)) |
| { |
| /* Result of these operations is always an int, |
| but that does not mean the operands should be |
| converted to ints! */ |
| result_type = integer_type_node; |
| op0 = truthvalue_conversion (op0); |
| op1 = truthvalue_conversion (op1); |
| converted = 1; |
| } |
| break; |
| |
| /* Shift operations: result has same type as first operand; |
| always convert second operand to int. |
| Also set SHORT_SHIFT if shifting rightward. */ |
| |
| case RSHIFT_EXPR: |
| if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) |
| { |
| if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0) |
| { |
| if (tree_int_cst_sgn (op1) < 0) |
| warning ("right shift count is negative"); |
| else |
| { |
| if (TREE_INT_CST_LOW (op1) | TREE_INT_CST_HIGH (op1)) |
| short_shift = 1; |
| if (TREE_INT_CST_HIGH (op1) != 0 |
| || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1) |
| >= TYPE_PRECISION (type0))) |
| warning ("right shift count >= width of type"); |
| } |
| } |
| /* Use the type of the value to be shifted. |
| This is what most traditional C compilers do. */ |
| result_type = type0; |
| /* Unless traditional, convert the shift-count to an integer, |
| regardless of size of value being shifted. */ |
| if (! flag_traditional) |
| { |
| if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) |
| op1 = convert (integer_type_node, op1); |
| /* Avoid converting op1 to result_type later. */ |
| converted = 1; |
| } |
| } |
| break; |
| |
| case LSHIFT_EXPR: |
| if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) |
| { |
| if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0) |
| { |
| if (tree_int_cst_sgn (op1) < 0) |
| warning ("left shift count is negative"); |
| else if (TREE_INT_CST_HIGH (op1) != 0 |
| || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1) |
| >= TYPE_PRECISION (type0))) |
| warning ("left shift count >= width of type"); |
| } |
| /* Use the type of the value to be shifted. |
| This is what most traditional C compilers do. */ |
| result_type = type0; |
| /* Unless traditional, convert the shift-count to an integer, |
| regardless of size of value being shifted. */ |
| if (! flag_traditional) |
| { |
| if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) |
| op1 = convert (integer_type_node, op1); |
| /* Avoid converting op1 to result_type later. */ |
| converted = 1; |
| } |
| } |
| break; |
| |
| case RROTATE_EXPR: |
| case LROTATE_EXPR: |
| if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) |
| { |
| if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0) |
| { |
| if (tree_int_cst_sgn (op1) < 0) |
| warning ("shift count is negative"); |
| else if (TREE_INT_CST_HIGH (op1) != 0 |
| || ((unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (op1) |
| >= TYPE_PRECISION (type0))) |
| warning ("shift count >= width of type"); |
| } |
| /* Use the type of the value to be shifted. |
| This is what most traditional C compilers do. */ |
| result_type = type0; |
| /* Unless traditional, convert the shift-count to an integer, |
| regardless of size of value being shifted. */ |
| if (! flag_traditional) |
| { |
| if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) |
| op1 = convert (integer_type_node, op1); |
| /* Avoid converting op1 to result_type later. */ |
| converted = 1; |
| } |
| } |
| break; |
| |
| case EQ_EXPR: |
| case NE_EXPR: |
| /* Result of comparison is always int, |
| but don't convert the args to int! */ |
| build_type = integer_type_node; |
| if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE |
| || code0 == COMPLEX_TYPE) |
| && (code1 == INTEGER_TYPE || code1 == REAL_TYPE |
| || code1 == COMPLEX_TYPE)) |
| short_compare = 1; |
| else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) |
| { |
| register tree tt0 = TREE_TYPE (type0); |
| register tree tt1 = TREE_TYPE (type1); |
| /* Anything compares with void *. void * compares with anything. |
| Otherwise, the targets must be compatible |
| and both must be object or both incomplete. */ |
| if (comp_target_types (type0, type1)) |
| result_type = common_type (type0, type1); |
| else if (TYPE_MAIN_VARIANT (tt0) == void_type_node) |
| { |
| /* op0 != orig_op0 detects the case of something |
| whose value is 0 but which isn't a valid null ptr const. */ |
| if (pedantic && (!integer_zerop (op0) || op0 != orig_op0) |
| && TREE_CODE (tt1) == FUNCTION_TYPE) |
| pedwarn ("ANSI C forbids comparison of `void *' with function pointer"); |
| } |
| else if (TYPE_MAIN_VARIANT (tt1) == void_type_node) |
| { |
| if (pedantic && (!integer_zerop (op1) || op1 != orig_op1) |
| && TREE_CODE (tt0) == FUNCTION_TYPE) |
| pedwarn ("ANSI C forbids comparison of `void *' with function pointer"); |
| } |
| else |
| pedwarn ("comparison of distinct pointer types lacks a cast"); |
| |
| if (result_type == NULL_TREE) |
| result_type = ptr_type_node; |
| } |
| else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST |
| && integer_zerop (op1)) |
| result_type = type0; |
| else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST |
| && integer_zerop (op0)) |
| result_type = type1; |
| else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) |
| { |
| result_type = type0; |
| if (! flag_traditional) |
| pedwarn ("comparison between pointer and integer"); |
| } |
| else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) |
| { |
| result_type = type1; |
| if (! flag_traditional) |
| pedwarn ("comparison between pointer and integer"); |
| } |
| break; |
| |
| case MAX_EXPR: |
| case MIN_EXPR: |
| if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) |
| && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) |
| shorten = 1; |
| else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) |
| { |
| if (comp_target_types (type0, type1)) |
| { |
| result_type = common_type (type0, type1); |
| if (pedantic |
| && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE) |
| pedwarn ("ANSI C forbids ordered comparisons of pointers to functions"); |
| } |
| else |
| { |
| result_type = ptr_type_node; |
| pedwarn ("comparison of distinct pointer types lacks a cast"); |
| } |
| } |
| break; |
| |
| case LE_EXPR: |
| case GE_EXPR: |
| case LT_EXPR: |
| case GT_EXPR: |
| build_type = integer_type_node; |
| if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) |
| && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) |
| short_compare = 1; |
| else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) |
| { |
| if (comp_target_types (type0, type1)) |
| { |
| result_type = common_type (type0, type1); |
| if ((TYPE_SIZE (TREE_TYPE (type0)) != 0) |
| != (TYPE_SIZE (TREE_TYPE (type1)) != 0)) |
| pedwarn ("comparison of complete and incomplete pointers"); |
| else if (pedantic |
| && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE) |
| pedwarn ("ANSI C forbids ordered comparisons of pointers to functions"); |
| } |
| else |
| { |
| result_type = ptr_type_node; |
| pedwarn ("comparison of distinct pointer types lacks a cast"); |
| } |
| } |
| else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST |
| && integer_zerop (op1)) |
| { |
| result_type = type0; |
| if (pedantic || extra_warnings) |
| pedwarn ("ordered comparison of pointer with integer zero"); |
| } |
| else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST |
| && integer_zerop (op0)) |
| { |
| result_type = type1; |
| if (pedantic) |
| pedwarn ("ordered comparison of pointer with integer zero"); |
| } |
| else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) |
| { |
| result_type = type0; |
| if (! flag_traditional) |
| pedwarn ("comparison between pointer and integer"); |
| } |
| else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) |
| { |
| result_type = type1; |
| if (! flag_traditional) |
| pedwarn ("comparison between pointer and integer"); |
| } |
| break; |
| } |
| |
| if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE) |
| && |
| (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE)) |
| { |
| int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE); |
| |
| if (shorten || common || short_compare) |
| result_type = common_type (type0, type1); |
| |
| /* For certain operations (which identify themselves by shorten != 0) |
| if both args were extended from the same smaller type, |
| do the arithmetic in that type and then extend. |
| |
| shorten !=0 and !=1 indicates a bitwise operation. |
| For them, this optimization is safe only if |
| both args are zero-extended or both are sign-extended. |
| Otherwise, we might change the result. |
| Eg, (short)-1 | (unsigned short)-1 is (int)-1 |
| but calculated in (unsigned short) it would be (unsigned short)-1. */ |
| |
| if (shorten && none_complex) |
| { |
| int unsigned0, unsigned1; |
| tree arg0 = get_narrower (op0, &unsigned0); |
| tree arg1 = get_narrower (op1, &unsigned1); |
| /* UNS is 1 if the operation to be done is an unsigned one. */ |
| int uns = TREE_UNSIGNED (result_type); |
| tree type; |
| |
| final_type = result_type; |
| |
| /* Handle the case that OP0 (or OP1) does not *contain* a conversion |
| but it *requires* conversion to FINAL_TYPE. */ |
| |
| if ((TYPE_PRECISION (TREE_TYPE (op0)) |
| == TYPE_PRECISION (TREE_TYPE (arg0))) |
| && TREE_TYPE (op0) != final_type) |
| unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0)); |
| if ((TYPE_PRECISION (TREE_TYPE (op1)) |
| == TYPE_PRECISION (TREE_TYPE (arg1))) |
| && TREE_TYPE (op1) != final_type) |
| unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1)); |
| |
| /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */ |
| |
| /* For bitwise operations, signedness of nominal type |
| does not matter. Consider only how operands were extended. */ |
| if (shorten == -1) |
| uns = unsigned0; |
| |
| /* Note that in all three cases below we refrain from optimizing |
| an unsigned operation on sign-extended args. |
| That would not be valid. */ |
| |
| /* Both args variable: if both extended in same way |
| from same width, do it in that width. |
| Do it unsigned if args were zero-extended. */ |
| if ((TYPE_PRECISION (TREE_TYPE (arg0)) |
| < TYPE_PRECISION (result_type)) |
| && (TYPE_PRECISION (TREE_TYPE (arg1)) |
| == TYPE_PRECISION (TREE_TYPE (arg0))) |
| && unsigned0 == unsigned1 |
| && (unsigned0 || !uns)) |
| result_type |
| = signed_or_unsigned_type (unsigned0, |
| common_type (TREE_TYPE (arg0), TREE_TYPE (arg1))); |
| else if (TREE_CODE (arg0) == INTEGER_CST |
| && (unsigned1 || !uns) |
| && (TYPE_PRECISION (TREE_TYPE (arg1)) |
| < TYPE_PRECISION (result_type)) |
| && (type = signed_or_unsigned_type (unsigned1, |
| TREE_TYPE (arg1)), |
| int_fits_type_p (arg0, type))) |
| result_type = type; |
| else if (TREE_CODE (arg1) == INTEGER_CST |
| && (unsigned0 || !uns) |
| && (TYPE_PRECISION (TREE_TYPE (arg0)) |
| < TYPE_PRECISION (result_type)) |
| && (type = signed_or_unsigned_type (unsigned0, |
| TREE_TYPE (arg0)), |
| int_fits_type_p (arg1, type))) |
| result_type = type; |
| } |
| |
| /* Shifts can be shortened if shifting right. */ |
| |
| if (short_shift) |
| { |
| int unsigned_arg; |
| tree arg0 = get_narrower (op0, &unsigned_arg); |
| |
| final_type = result_type; |
| |
| if (arg0 == op0 && final_type == TREE_TYPE (op0)) |
| unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0)); |
| |
| if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type) |
| /* We can shorten only if the shift count is less than the |
| number of bits in the smaller type size. */ |
| && TREE_INT_CST_HIGH (op1) == 0 |
| && TYPE_PRECISION (TREE_TYPE (arg0)) > TREE_INT_CST_LOW (op1) |
| /* If arg is sign-extended and then unsigned-shifted, |
| we can simulate this with a signed shift in arg's type |
| only if the extended result is at least twice as wide |
| as the arg. Otherwise, the shift could use up all the |
| ones made by sign-extension and bring in zeros. |
| We can't optimize that case at all, but in most machines |
| it never happens because available widths are 2**N. */ |
| && (!TREE_UNSIGNED (final_type) |
| || unsigned_arg |
| || 2 * TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (result_type))) |
| { |
| /* Do an unsigned shift if the operand was zero-extended. */ |
| result_type |
| = signed_or_unsigned_type (unsigned_arg, |
| TREE_TYPE (arg0)); |
| /* Convert value-to-be-shifted to that type. */ |
| if (TREE_TYPE (op0) != result_type) |
| op0 = convert (result_type, op0); |
| converted = 1; |
| } |
| } |
| |
| /* Comparison operations are shortened too but differently. |
| They identify themselves by setting short_compare = 1. */ |
| |
| if (short_compare) |
| { |
| /* Don't write &op0, etc., because that would prevent op0 |
| from being kept in a register. |
| Instead, make copies of the our local variables and |
| pass the copies by reference, then copy them back afterward. */ |
| tree xop0 = op0, xop1 = op1, xresult_type = result_type; |
| enum tree_code xresultcode = resultcode; |
| tree val |
| = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode); |
| if (val != 0) |
| return val; |
| op0 = xop0, op1 = xop1; |
| converted = 1; |
| resultcode = xresultcode; |
| |
| if ((warn_sign_compare < 0 ? extra_warnings : warn_sign_compare != 0) |
| && skip_evaluation == 0) |
| { |
| int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0)); |
| int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1)); |
| |
| int unsignedp0, unsignedp1; |
| tree primop0 = get_narrower (op0, &unsignedp0); |
| tree primop1 = get_narrower (op1, &unsignedp1); |
| |
| /* Avoid spurious warnings for comparison with enumerators. */ |
| |
| xop0 = orig_op0; |
| xop1 = orig_op1; |
| STRIP_TYPE_NOPS (xop0); |
| STRIP_TYPE_NOPS (xop1); |
| |
| /* Give warnings for comparisons between signed and unsigned |
| quantities that may fail. */ |
| /* Do the checking based on the original operand trees, so that |
| casts will be considered, but default promotions won't be. */ |
| |
| /* Do not warn if the comparison is being done in a signed type, |
| since the signed type will only be chosen if it can represent |
| all the values of the unsigned type. */ |
| if (! TREE_UNSIGNED (result_type)) |
| /* OK */; |
| /* Do not warn if both operands are unsigned. */ |
| else if (op0_signed == op1_signed) |
| /* OK */; |
| /* Do not warn if the signed quantity is an unsuffixed |
| integer literal (or some static constant expression |
| involving such literals) and it is non-negative. */ |
| else if ((op0_signed && TREE_CODE (xop0) == INTEGER_CST |
| && tree_int_cst_sgn (xop0) >= 0) |
| || (op1_signed && TREE_CODE (xop1) == INTEGER_CST |
| && tree_int_cst_sgn (xop1) >= 0)) |
| /* OK */; |
| /* Do not warn if the comparison is an equality operation, |
| the unsigned quantity is an integral constant and it does |
| not use the most significant bit of result_type. */ |
| else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR) |
| && ((op0_signed && TREE_CODE (xop1) == INTEGER_CST |
| && int_fits_type_p (xop1, signed_type (result_type))) |
| || (op1_signed && TREE_CODE (xop0) == INTEGER_CST |
| && int_fits_type_p (xop0, signed_type (result_type))))) |
| /* OK */; |
| else |
| warning ("comparison between signed and unsigned"); |
| |
| /* Warn if two unsigned values are being compared in a size |
| larger than their original size, and one (and only one) is the |
| result of a `~' operator. This comparison will always fail. |
| |
| Also warn if one operand is a constant, and the constant |
| does not have all bits set that are set in the ~ operand |
| when it is extended. */ |
| |
| if ((TREE_CODE (primop0) == BIT_NOT_EXPR) |
| != (TREE_CODE (primop1) == BIT_NOT_EXPR)) |
| { |
| if (TREE_CODE (primop0) == BIT_NOT_EXPR) |
| primop0 = get_narrower (TREE_OPERAND (primop0, 0), |
| &unsignedp0); |
| else |
| primop1 = get_narrower (TREE_OPERAND (primop1, 0), |
| &unsignedp1); |
| |
| if (TREE_CODE (primop0) == INTEGER_CST |
| || TREE_CODE (primop1) == INTEGER_CST) |
| { |
| tree primop; |
| long constant, mask; |
| int unsignedp, bits; |
| |
| if (TREE_CODE (primop0) == INTEGER_CST) |
| { |
| primop = primop1; |
| unsignedp = unsignedp1; |
| constant = TREE_INT_CST_LOW (primop0); |
| } |
| else |
| { |
| primop = primop0; |
| unsignedp = unsignedp0; |
| constant = TREE_INT_CST_LOW (primop1); |
| } |
| |
| bits = TYPE_PRECISION (TREE_TYPE (primop)); |
| if (bits < TYPE_PRECISION (result_type) |
| && bits < HOST_BITS_PER_LONG && unsignedp) |
| { |
| mask = (~0L) << bits; |
| if ((mask & constant) != mask) |
| warning ("comparison of promoted ~unsigned with constant"); |
| } |
| } |
| else if (unsignedp0 && unsignedp1 |
| && (TYPE_PRECISION (TREE_TYPE (primop0)) |
| < TYPE_PRECISION (result_type)) |
| && (TYPE_PRECISION (TREE_TYPE (primop1)) |
| < TYPE_PRECISION (result_type))) |
| warning ("comparison of promoted ~unsigned with unsigned"); |
| } |
| } |
| } |
| } |
| |
| /* At this point, RESULT_TYPE must be nonzero to avoid an error message. |
| If CONVERTED is zero, both args will be converted to type RESULT_TYPE. |
| Then the expression will be built. |
| It will be given type FINAL_TYPE if that is nonzero; |
| otherwise, it will be given type RESULT_TYPE. */ |
| |
| if (!result_type) |
| { |
| binary_op_error (code); |
| return error_mark_node; |
| } |
| |
| if (! converted) |
| { |
| if (TREE_TYPE (op0) != result_type) |
| op0 = convert (result_type, op0); |
| if (TREE_TYPE (op1) != result_type) |
| op1 = convert (result_type, op1); |
| } |
| |
| if (build_type == NULL_TREE) |
| build_type = result_type; |
| |
| { |
| register tree result = build (resultcode, build_type, op0, op1); |
| register tree folded; |
| |
| folded = fold (result); |
| if (folded == result) |
| TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1); |
| if (final_type != 0) |
| return convert (final_type, folded); |
| return folded; |
| } |
| } |
| |
| /* Return a tree for the sum or difference (RESULTCODE says which) |
| of pointer PTROP and integer INTOP. */ |
| |
| static tree |
| pointer_int_sum (resultcode, ptrop, intop) |
| enum tree_code resultcode; |
| register tree ptrop, intop; |
| { |
| tree size_exp; |
| |
| register tree result; |
| register tree folded; |
| |
| /* The result is a pointer of the same type that is being added. */ |
| |
| register tree result_type = TREE_TYPE (ptrop); |
| |
| if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE) |
| { |
| if (pedantic || warn_pointer_arith) |
| pedwarn ("pointer of type `void *' used in arithmetic"); |
| size_exp = integer_one_node; |
| } |
| else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE) |
| { |
| if (pedantic || warn_pointer_arith) |
| pedwarn ("pointer to a function used in arithmetic"); |
| size_exp = integer_one_node; |
| } |
| else |
| size_exp = c_size_in_bytes (TREE_TYPE (result_type)); |
| |
| /* If what we are about to multiply by the size of the elements |
| contains a constant term, apply distributive law |
| and multiply that constant term separately. |
| This helps produce common subexpressions. */ |
| |
| if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR) |
| && ! TREE_CONSTANT (intop) |
| && TREE_CONSTANT (TREE_OPERAND (intop, 1)) |
| && TREE_CONSTANT (size_exp) |
| /* If the constant comes from pointer subtraction, |
| skip this optimization--it would cause an error. */ |
| && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE |
| /* If the constant is unsigned, and smaller than the pointer size, |
| then we must skip this optimization. This is because it could cause |
| an overflow error if the constant is negative but INTOP is not. */ |
| && (! TREE_UNSIGNED (TREE_TYPE (intop)) |
| || (TYPE_PRECISION (TREE_TYPE (intop)) |
| == TYPE_PRECISION (TREE_TYPE (ptrop))))) |
| { |
| enum tree_code subcode = resultcode; |
| tree int_type = TREE_TYPE (intop); |
| if (TREE_CODE (intop) == MINUS_EXPR) |
| subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR); |
| /* Convert both subexpression types to the type of intop, |
| because weird cases involving pointer arithmetic |
| can result in a sum or difference with different type args. */ |
| ptrop = build_binary_op (subcode, ptrop, |
| convert (int_type, TREE_OPERAND (intop, 1)), 1); |
| intop = convert (int_type, TREE_OPERAND (intop, 0)); |
| } |
| |
| /* Convert the integer argument to a type the same size as sizetype |
| so the multiply won't overflow spuriously. */ |
| |
| if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype) |
| || TREE_UNSIGNED (TREE_TYPE (intop)) != TREE_UNSIGNED (sizetype)) |
| intop = convert (type_for_size (TYPE_PRECISION (sizetype), |
| TREE_UNSIGNED (sizetype)), intop); |
| |
| /* Replace the integer argument with a suitable product by the object size. |
| Do this multiplication as signed, then convert to the appropriate |
| pointer type (actually unsigned integral). */ |
| |
| intop = convert (result_type, |
| build_binary_op (MULT_EXPR, intop, |
| convert (TREE_TYPE (intop), size_exp), 1)); |
| |
| /* Create the sum or difference. */ |
| |
| result = build (resultcode, result_type, ptrop, intop); |
| |
| folded = fold (result); |
| if (folded == result) |
| TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop); |
| return folded; |
| } |
| |
| /* Return a tree for the difference of pointers OP0 and OP1. |
| The resulting tree has type int. */ |
| |
| static tree |
| pointer_diff (op0, op1) |
| register tree op0, op1; |
| { |
| register tree result, folded; |
| tree restype = ptrdiff_type_node; |
| |
| tree target_type = TREE_TYPE (TREE_TYPE (op0)); |
| |
| if (pedantic || warn_pointer_arith) |
| { |
| if (TREE_CODE (target_type) == VOID_TYPE) |
| pedwarn ("pointer of type `void *' used in subtraction"); |
| if (TREE_CODE (target_type) == FUNCTION_TYPE) |
| pedwarn ("pointer to a function used in subtraction"); |
| } |
| |
| /* First do the subtraction as integers; |
| then drop through to build the divide operator. |
| Do not do default conversions on the minus operator |
| in case restype is a short type. */ |
| |
| op0 = build_binary_op (MINUS_EXPR, convert (restype, op0), |
| convert (restype, op1), 0); |
| /* This generates an error if op1 is pointer to incomplete type. */ |
| if (TYPE_SIZE (TREE_TYPE (TREE_TYPE (op1))) == 0) |
| error ("arithmetic on pointer to an incomplete type"); |
| |
| /* This generates an error if op0 is pointer to incomplete type. */ |
| op1 = c_size_in_bytes (target_type); |
| |
| /* Divide by the size, in easiest possible way. */ |
| |
| result = build (EXACT_DIV_EXPR, restype, op0, convert (restype, op1)); |
| |
| folded = fold (result); |
| if (folded == result) |
| TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1); |
| return folded; |
| } |
| |
| /* Construct and perhaps optimize a tree representation |
| for a unary operation. CODE, a tree_code, specifies the operation |
| and XARG is the operand. NOCONVERT nonzero suppresses |
| the default promotions (such as from short to int). */ |
| |
| tree |
| build_unary_op (code, xarg, noconvert) |
| enum tree_code code; |
| tree xarg; |
| int noconvert; |
| { |
| /* No default_conversion here. It causes trouble for ADDR_EXPR. */ |
| register tree arg = xarg; |
| register tree argtype = 0; |
| register enum tree_code typecode = TREE_CODE (TREE_TYPE (arg)); |
| char *errstring = NULL; |
| tree val; |
| |
| if (typecode == ERROR_MARK) |
| return error_mark_node; |
| if (typecode == ENUMERAL_TYPE) |
| typecode = INTEGER_TYPE; |
| |
| switch (code) |
| { |
| case CONVERT_EXPR: |
| /* This is used for unary plus, because a CONVERT_EXPR |
| is enough to prevent anybody from looking inside for |
| associativity, but won't generate any code. */ |
| if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE |
| || typecode == COMPLEX_TYPE)) |
| errstring = "wrong type argument to unary plus"; |
| else if (!noconvert) |
| arg = default_conversion (arg); |
| break; |
| |
| case NEGATE_EXPR: |
| if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE |
| || typecode == COMPLEX_TYPE)) |
| errstring = "wrong type argument to unary minus"; |
| else if (!noconvert) |
| arg = default_conversion (arg); |
| break; |
| |
| case BIT_NOT_EXPR: |
| if (typecode == COMPLEX_TYPE) |
| { |
| code = CONJ_EXPR; |
| if (!noconvert) |
| arg = default_conversion (arg); |
| } |
| else if (typecode != INTEGER_TYPE) |
| errstring = "wrong type argument to bit-complement"; |
| else if (!noconvert) |
| arg = default_conversion (arg); |
| break; |
| |
| case ABS_EXPR: |
| if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE |
| || typecode == COMPLEX_TYPE)) |
| errstring = "wrong type argument to abs"; |
| else if (!noconvert) |
| arg = default_conversion (arg); |
| break; |
| |
| case CONJ_EXPR: |
| /* Conjugating a real value is a no-op, but allow it anyway. */ |
| if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE |
| || typecode == COMPLEX_TYPE)) |
| errstring = "wrong type argument to conjugation"; |
| else if (!noconvert) |
| arg = default_conversion (arg); |
| break; |
| |
| case TRUTH_NOT_EXPR: |
| if (typecode != INTEGER_TYPE |
| && typecode != REAL_TYPE && typecode != POINTER_TYPE |
| && typecode != COMPLEX_TYPE |
| /* These will convert to a pointer. */ |
| && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE) |
| { |
| errstring = "wrong type argument to unary exclamation mark"; |
| break; |
| } |
| arg = truthvalue_conversion (arg); |
| return invert_truthvalue (arg); |
| |
| case NOP_EXPR: |
| break; |
| |
| case REALPART_EXPR: |
| if (TREE_CODE (arg) == COMPLEX_CST) |
| return TREE_REALPART (arg); |
| else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) |
| return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg)); |
| else |
| return arg; |
| |
| case IMAGPART_EXPR: |
| if (TREE_CODE (arg) == COMPLEX_CST) |
| return TREE_IMAGPART (arg); |
| else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) |
| return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg)); |
| else |
| return convert (TREE_TYPE (arg), integer_zero_node); |
| |
| case PREINCREMENT_EXPR: |
| case POSTINCREMENT_EXPR: |
| case PREDECREMENT_EXPR: |
| case POSTDECREMENT_EXPR: |
| /* Handle complex lvalues (when permitted) |
| by reduction to simpler cases. */ |
| |
| val = unary_complex_lvalue (code, arg); |
| if (val != 0) |
| return val; |
| |
| /* Increment or decrement the real part of the value, |
| and don't change the imaginary part. */ |
| if (typecode == COMPLEX_TYPE) |
| { |
| tree real, imag; |
| |
| arg = stabilize_reference (arg); |
| real = build_unary_op (REALPART_EXPR, arg, 1); |
| imag = build_unary_op (IMAGPART_EXPR, arg, 1); |
| return build (COMPLEX_EXPR, TREE_TYPE (arg), |
| build_unary_op (code, real, 1), imag); |
| } |
| |
| /* Report invalid types. */ |
| |
| if (typecode != POINTER_TYPE |
| && typecode != INTEGER_TYPE && typecode != REAL_TYPE) |
| { |
| if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) |
| errstring ="wrong type argument to increment"; |
| else |
| errstring ="wrong type argument to decrement"; |
| break; |
| } |
| |
| { |
| register tree inc; |
| tree result_type = TREE_TYPE (arg); |
| |
| arg = get_unwidened (arg, 0); |
| argtype = TREE_TYPE (arg); |
| |
| /* Compute the increment. */ |
| |
| if (typecode == POINTER_TYPE) |
| { |
| /* If pointer target is an undefined struct, |
| we just cannot know how to do the arithmetic. */ |
| if (TYPE_SIZE (TREE_TYPE (result_type)) == 0) |
| error ("%s of pointer to unknown structure", |
| ((code == PREINCREMENT_EXPR |
| || code == POSTINCREMENT_EXPR) |
| ? "increment" : "decrement")); |
| else if ((pedantic || warn_pointer_arith) |
| && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE |
| || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)) |
| pedwarn ("wrong type argument to %s", |
| ((code == PREINCREMENT_EXPR |
| || code == POSTINCREMENT_EXPR) |
| ? "increment" : "decrement")); |
| inc = c_size_in_bytes (TREE_TYPE (result_type)); |
| } |
| else |
| inc = integer_one_node; |
| |
| inc = convert (argtype, inc); |
| |
| /* Handle incrementing a cast-expression. */ |
| |
| while (1) |
| switch (TREE_CODE (arg)) |
| { |
| case NOP_EXPR: |
| case CONVERT_EXPR: |
| case FLOAT_EXPR: |
| case FIX_TRUNC_EXPR: |
| case FIX_FLOOR_EXPR: |
| case FIX_ROUND_EXPR: |
| case FIX_CEIL_EXPR: |
| pedantic_lvalue_warning (CONVERT_EXPR); |
| /* If the real type has the same machine representation |
| as the type it is cast to, we can make better output |
| by adding directly to the inside of the cast. */ |
| if ((TREE_CODE (TREE_TYPE (arg)) |
| == TREE_CODE (TREE_TYPE (TREE_OPERAND (arg, 0)))) |
| && (TYPE_MODE (TREE_TYPE (arg)) |
| == TYPE_MODE (TREE_TYPE (TREE_OPERAND (arg, 0))))) |
| arg = TREE_OPERAND (arg, 0); |
| else |
| { |
| tree incremented, modify, value; |
| arg = stabilize_reference (arg); |
| if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR) |
| value = arg; |
| else |
| value = save_expr (arg); |
| incremented = build (((code == PREINCREMENT_EXPR |
| || code == POSTINCREMENT_EXPR) |
| ? PLUS_EXPR : MINUS_EXPR), |
| argtype, value, inc); |
| TREE_SIDE_EFFECTS (incremented) = 1; |
| modify = build_modify_expr (arg, NOP_EXPR, incremented); |
| value = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value); |
| TREE_USED (value) = 1; |
| return value; |
| } |
| break; |
| |
| default: |
| goto give_up; |
| } |
| give_up: |
| |
| /* Complain about anything else that is not a true lvalue. */ |
| if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR |
| || code == POSTINCREMENT_EXPR) |
| ? "increment" : "decrement"))) |
| return error_mark_node; |
| |
| /* Report a read-only lvalue. */ |
| if (TREE_READONLY (arg)) |
| readonly_warning (arg, |
| ((code == PREINCREMENT_EXPR |
| || code == POSTINCREMENT_EXPR) |
| ? "increment" : "decrement")); |
| |
| val = build (code, TREE_TYPE (arg), arg, inc); |
| TREE_SIDE_EFFECTS (val) = 1; |
| val = convert (result_type, val); |
| if (TREE_CODE (val) != code) |
| TREE_NO_UNUSED_WARNING (val) = 1; |
| return val; |
| } |
| |
| case ADDR_EXPR: |
| /* Note that this operation never does default_conversion |
| regardless of NOCONVERT. */ |
| |
| /* Let &* cancel out to simplify resulting code. */ |
| if (TREE_CODE (arg) == INDIRECT_REF) |
| { |
| /* Don't let this be an lvalue. */ |
| if (lvalue_p (TREE_OPERAND (arg, 0))) |
| return non_lvalue (TREE_OPERAND (arg, 0)); |
| return TREE_OPERAND (arg, 0); |
| } |
| |
| /* For &x[y], return x+y */ |
| if (TREE_CODE (arg) == ARRAY_REF) |
| { |
| if (mark_addressable (TREE_OPERAND (arg, 0)) == 0) |
| return error_mark_node; |
| return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0), |
| TREE_OPERAND (arg, 1), 1); |
| } |
| |
| /* Handle complex lvalues (when permitted) |
| by reduction to simpler cases. */ |
| val = unary_complex_lvalue (code, arg); |
| if (val != 0) |
| return val; |
| |
| #if 0 /* Turned off because inconsistent; |
| float f; *&(int)f = 3.4 stores in int format |
| whereas (int)f = 3.4 stores in float format. */ |
| /* Address of a cast is just a cast of the address |
| of the operand of the cast. */ |
| switch (TREE_CODE (arg)) |
| { |
| case NOP_EXPR: |
| case CONVERT_EXPR: |
| case FLOAT_EXPR: |
| case FIX_TRUNC_EXPR: |
| case FIX_FLOOR_EXPR: |
| case FIX_ROUND_EXPR: |
| case FIX_CEIL_EXPR: |
| if (pedantic) |
| pedwarn ("ANSI C forbids the address of a cast expression"); |
| return convert (build_pointer_type (TREE_TYPE (arg)), |
| build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), |
| 0)); |
| } |
| #endif |
| |
| /* Allow the address of a constructor if all the elements |
| are constant. */ |
| if (TREE_CODE (arg) == CONSTRUCTOR && TREE_CONSTANT (arg)) |
| ; |
| /* Anything not already handled and not a true memory reference |
| is an error. */ |
| else if (typecode != FUNCTION_TYPE && !lvalue_or_else (arg, "unary `&'")) |
| return error_mark_node; |
| |