1 /* Fold a constant sub-tree into a single node for C-compiler
2 Copyright (C) 1987-2023 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20 #ifndef GCC_FOLD_CONST_H
21 #define GCC_FOLD_CONST_H
22
23 /* Nonzero if we are folding constants inside an initializer or a C++
24 manifestly-constant-evaluated context; zero otherwise.
25 Should be used when folding in initializer enables additional
26 optimizations. */
27 extern int folding_initializer;
28 /* Nonzero if we are folding C++ manifestly-constant-evaluated context; zero
29 otherwise.
30 Should be used when certain constructs shouldn't be optimized
31 during folding in that context. */
32 extern bool folding_cxx_constexpr;
33
34 /* Convert between trees and native memory representation. */
35 extern int native_encode_expr (const_tree, unsigned char *, int, int off = -1);
36 extern int native_encode_initializer (tree, unsigned char *, int,
37 int off = -1, unsigned char * = nullptr);
38 extern tree native_interpret_expr (tree, const unsigned char *, int);
39 extern tree native_interpret_real (tree, const unsigned char *, int);
40 extern bool can_native_interpret_type_p (tree);
41 extern tree native_interpret_aggregate (tree, const unsigned char *, int, int);
42 extern tree find_bitfield_repr_type (int, int);
43 extern void shift_bytes_in_array_left (unsigned char *, unsigned int,
44 unsigned int);
45 extern void shift_bytes_in_array_right (unsigned char *, unsigned int,
46 unsigned int);
47
48 /* Fold constants as much as possible in an expression.
49 Returns the simplified expression.
50 Acts only on the top level of the expression;
51 if the argument itself cannot be simplified, its
52 subexpressions are not changed. */
53
54 extern tree fold (tree);
55 extern tree fold_init (tree);
56 #define fold_unary(CODE,T1,T2)\
57 fold_unary_loc (UNKNOWN_LOCATION, CODE, T1, T2)
58 extern tree fold_unary_loc (location_t, enum tree_code, tree, tree);
59 #define fold_unary_ignore_overflow(CODE,T1,T2)\
60 fold_unary_ignore_overflow_loc (UNKNOWN_LOCATION, CODE, T1, T2)
61 extern tree fold_unary_ignore_overflow_loc (location_t, enum tree_code, tree, tree);
62 #define fold_binary(CODE,T1,T2,T3)\
63 fold_binary_loc (UNKNOWN_LOCATION, CODE, T1, T2, T3)
64 extern tree fold_binary_loc (location_t, enum tree_code, tree, tree, tree);
65 #define fold_ternary(CODE,T1,T2,T3,T4)\
66 fold_ternary_loc (UNKNOWN_LOCATION, CODE, T1, T2, T3, T4)
67 extern tree fold_ternary_loc (location_t, enum tree_code, tree, tree, tree, tree);
68 #define fold_build1(c,t1,t2)\
69 fold_build1_loc (UNKNOWN_LOCATION, c, t1, t2 MEM_STAT_INFO)
70 extern tree fold_build1_loc (location_t, enum tree_code, tree,
71 tree CXX_MEM_STAT_INFO);
72 #define fold_build2(c,t1,t2,t3)\
73 fold_build2_loc (UNKNOWN_LOCATION, c, t1, t2, t3 MEM_STAT_INFO)
74 extern tree fold_build2_loc (location_t, enum tree_code, tree, tree,
75 tree CXX_MEM_STAT_INFO);
76 #define fold_build3(c,t1,t2,t3,t4)\
77 fold_build3_loc (UNKNOWN_LOCATION, c, t1, t2, t3, t4 MEM_STAT_INFO)
78 extern tree fold_build3_loc (location_t, enum tree_code, tree, tree, tree,
79 tree CXX_MEM_STAT_INFO);
80 extern tree fold_build1_initializer_loc (location_t, enum tree_code, tree, tree);
81 extern tree fold_build2_initializer_loc (location_t, enum tree_code, tree, tree, tree);
82 #define fold_build_call_array(T1,T2,N,T4)\
83 fold_build_call_array_loc (UNKNOWN_LOCATION, T1, T2, N, T4)
84 extern tree fold_build_call_array_loc (location_t, tree, tree, int, tree *);
85 #define fold_build_call_array_initializer(T1,T2,N,T4)\
86 fold_build_call_array_initializer_loc (UNKNOWN_LOCATION, T1, T2, N, T4)
87 extern tree fold_build_call_array_initializer_loc (location_t, tree, tree, int, tree *);
88 extern tree fold_binary_initializer_loc (location_t, tree_code, tree, tree, tree);
89 extern tree get_array_ctor_element_at_index (tree, offset_int,
90 unsigned * = NULL);
91 extern bool fold_convertible_p (const_tree, const_tree);
92 #define fold_convert(T1,T2)\
93 fold_convert_loc (UNKNOWN_LOCATION, T1, T2)
94 extern tree fold_convert_loc (location_t, tree, tree);
95 extern tree fold_single_bit_test (location_t, enum tree_code, tree, tree, tree);
96 extern tree fold_ignored_result (tree);
97 extern tree fold_abs_const (tree, tree);
98 extern tree fold_indirect_ref_1 (location_t, tree, tree);
99 extern void fold_defer_overflow_warnings (void);
100 extern void fold_undefer_overflow_warnings (bool, const gimple *, int);
101 extern void fold_undefer_and_ignore_overflow_warnings (void);
102 extern bool fold_deferring_overflow_warnings_p (void);
103 extern void fold_overflow_warning (const char*, enum warn_strict_overflow_code);
104 extern enum tree_code fold_div_compare (enum tree_code, tree, tree,
105 tree *, tree *, bool *);
106 extern bool operand_equal_p (const_tree, const_tree, unsigned int flags = 0);
107 extern int multiple_of_p (tree, const_tree, const_tree, bool = true);
108 #define omit_one_operand(T1,T2,T3)\
109 omit_one_operand_loc (UNKNOWN_LOCATION, T1, T2, T3)
110 extern tree omit_one_operand_loc (location_t, tree, tree, tree);
111 #define omit_two_operands(T1,T2,T3,T4)\
112 omit_two_operands_loc (UNKNOWN_LOCATION, T1, T2, T3, T4)
113 extern tree omit_two_operands_loc (location_t, tree, tree, tree, tree);
114 #define invert_truthvalue(T)\
115 invert_truthvalue_loc (UNKNOWN_LOCATION, T)
116 extern tree invert_truthvalue_loc (location_t, tree);
117 extern tree fold_unary_to_constant (enum tree_code, tree, tree);
118 extern tree fold_binary_to_constant (enum tree_code, tree, tree, tree);
119 extern tree fold_bit_and_mask (tree, tree, enum tree_code,
120 tree, enum tree_code, tree, tree,
121 tree, enum tree_code, tree, tree, tree *);
122 extern tree fold_read_from_constant_string (tree);
123 extern tree fold_read_from_vector (tree, poly_uint64);
124 #if GCC_VEC_PERN_INDICES_H
125 extern tree fold_vec_perm (tree, tree, tree, const vec_perm_indices &);
126 #endif
127 extern bool wide_int_binop (wide_int &res, enum tree_code,
128 const wide_int &arg1, const wide_int &arg2,
129 signop, wi::overflow_type *);
130 extern tree int_const_binop (enum tree_code, const_tree, const_tree, int = 1);
131 #define build_fold_addr_expr(T)\
132 build_fold_addr_expr_loc (UNKNOWN_LOCATION, (T))
133 extern tree build_fold_addr_expr_loc (location_t, tree);
134 #define build_fold_addr_expr_with_type(T,TYPE)\
135 build_fold_addr_expr_with_type_loc (UNKNOWN_LOCATION, (T), TYPE)
136 extern tree build_fold_addr_expr_with_type_loc (location_t, tree, tree);
137 extern tree fold_build_cleanup_point_expr (tree type, tree expr);
138 #define build_fold_indirect_ref(T)\
139 build_fold_indirect_ref_loc (UNKNOWN_LOCATION, T)
140 extern tree build_fold_indirect_ref_loc (location_t, tree);
141 #define fold_indirect_ref(T)\
142 fold_indirect_ref_loc (UNKNOWN_LOCATION, T)
143 extern tree fold_indirect_ref_loc (location_t, tree);
144 extern tree build_simple_mem_ref_loc (location_t, tree);
145 #define build_simple_mem_ref(T)\
146 build_simple_mem_ref_loc (UNKNOWN_LOCATION, T)
147 extern poly_offset_int mem_ref_offset (const_tree);
148 extern tree build_invariant_address (tree, tree, poly_int64);
149 extern tree constant_boolean_node (bool, tree);
150 extern tree div_if_zero_remainder (const_tree, const_tree);
151
152 extern bool tree_swap_operands_p (const_tree, const_tree);
153 extern enum tree_code swap_tree_comparison (enum tree_code);
154
155 extern bool ptr_difference_const (tree, tree, poly_int64_pod *);
156 extern enum tree_code invert_tree_comparison (enum tree_code, bool);
157 extern bool inverse_conditions_p (const_tree, const_tree);
158
159 extern bool tree_unary_nonzero_warnv_p (enum tree_code, tree, tree, bool *);
160 extern bool tree_binary_nonzero_warnv_p (enum tree_code, tree, tree, tree op1,
161 bool *);
162 extern bool tree_single_nonzero_warnv_p (tree, bool *);
163 extern bool tree_unary_nonnegative_warnv_p (enum tree_code, tree, tree,
164 bool *, int);
165 extern bool tree_binary_nonnegative_warnv_p (enum tree_code, tree, tree, tree,
166 bool *, int);
167 extern bool tree_single_nonnegative_warnv_p (tree, bool *, int);
168 extern bool tree_call_nonnegative_warnv_p (tree, combined_fn, tree, tree,
169 bool *, int);
170
171 extern bool integer_valued_real_unary_p (tree_code, tree, int);
172 extern bool integer_valued_real_binary_p (tree_code, tree, tree, int);
173 extern bool integer_valued_real_call_p (combined_fn, tree, tree, int);
174 extern bool integer_valued_real_single_p (tree, int);
175 extern bool integer_valued_real_p (tree, int = 0);
176
177 extern bool fold_real_zero_addition_p (const_tree, const_tree, const_tree,
178 int);
179 extern tree combine_comparisons (location_t, enum tree_code, enum tree_code,
180 enum tree_code, tree, tree, tree);
181 extern void debug_fold_checksum (const_tree);
182 extern bool may_negate_without_overflow_p (const_tree);
183 #define round_up(T,N) round_up_loc (UNKNOWN_LOCATION, T, N)
184 extern tree round_up_loc (location_t, tree, unsigned int);
185 #define round_down(T,N) round_down_loc (UNKNOWN_LOCATION, T, N)
186 extern tree round_down_loc (location_t, tree, int);
187 extern tree size_int_kind (poly_int64, enum size_type_kind);
188 #define size_binop(CODE,T1,T2)\
189 size_binop_loc (UNKNOWN_LOCATION, CODE, T1, T2)
190 extern tree size_binop_loc (location_t, enum tree_code, tree, tree);
191 #define size_diffop(T1,T2)\
192 size_diffop_loc (UNKNOWN_LOCATION, T1, T2)
193 extern tree size_diffop_loc (location_t, tree, tree);
194
195 /* Return an expr equal to X but certainly not valid as an lvalue. */
196 #define non_lvalue(T) non_lvalue_loc (UNKNOWN_LOCATION, T)
197 extern tree non_lvalue_loc (location_t, tree);
198
199 extern bool tree_expr_nonzero_p (tree);
200 extern bool tree_expr_nonnegative_p (tree);
201 extern bool tree_expr_nonnegative_warnv_p (tree, bool *, int = 0);
202 extern bool tree_expr_finite_p (const_tree);
203 extern bool tree_expr_infinite_p (const_tree);
204 extern bool tree_expr_maybe_infinite_p (const_tree);
205 extern bool tree_expr_signaling_nan_p (const_tree);
206 extern bool tree_expr_maybe_signaling_nan_p (const_tree);
207 extern bool tree_expr_nan_p (const_tree);
208 extern bool tree_expr_maybe_nan_p (const_tree);
209 extern bool tree_expr_maybe_real_minus_zero_p (const_tree);
210 extern tree make_range (tree, int *, tree *, tree *, bool *);
211 extern tree make_range_step (location_t, enum tree_code, tree, tree, tree,
212 tree *, tree *, int *, bool *);
213 extern tree range_check_type (tree);
214 extern tree build_range_check (location_t, tree, tree, int, tree, tree);
215 extern bool merge_ranges (int *, tree *, tree *, int, tree, tree, int,
216 tree, tree);
217 extern tree sign_bit_p (tree, const_tree);
218 extern bool simple_condition_p (tree);
219 extern tree exact_inverse (tree, tree);
220 extern bool expr_not_equal_to (tree t, const wide_int &);
221 extern tree const_unop (enum tree_code, tree, tree);
222 extern tree const_binop (enum tree_code, tree, tree, tree);
223 extern bool negate_mathfn_p (combined_fn);
224 extern const char *getbyterep (tree, unsigned HOST_WIDE_INT *);
225 extern const char *c_getstr (tree);
226 extern wide_int tree_nonzero_bits (const_tree);
227 extern int address_compare (tree_code, tree, tree, tree, tree &, tree &,
228 poly_int64 &, poly_int64 &, bool);
229 extern tree ctor_single_nonzero_element (const_tree);
230
231 /* Return OFF converted to a pointer offset type suitable as offset for
232 POINTER_PLUS_EXPR. Use location LOC for this conversion. */
233 extern tree convert_to_ptrofftype_loc (location_t loc, tree off);
234
235 #define convert_to_ptrofftype(t) convert_to_ptrofftype_loc (UNKNOWN_LOCATION, t)
236
237 /* Build and fold a POINTER_PLUS_EXPR at LOC offsetting PTR by OFF. */
238 extern tree fold_build_pointer_plus_loc (location_t loc, tree ptr, tree off);
239
240 #define fold_build_pointer_plus(p,o) \
241 fold_build_pointer_plus_loc (UNKNOWN_LOCATION, p, o)
242
243 /* Build and fold a POINTER_PLUS_EXPR at LOC offsetting PTR by OFF. */
244 extern tree fold_build_pointer_plus_hwi_loc (location_t loc, tree ptr, HOST_WIDE_INT off);
245
246 #define fold_build_pointer_plus_hwi(p,o) \
247 fold_build_pointer_plus_hwi_loc (UNKNOWN_LOCATION, p, o)
248
249 /* In gimple-fold.cc. */
250 extern void clear_type_padding_in_mask (tree, unsigned char *);
251 extern bool clear_padding_type_may_have_padding_p (tree);
252 extern bool arith_overflowed_p (enum tree_code, const_tree, const_tree,
253 const_tree);
254
255 /* Class used to compare gimple operands. */
256
257 class operand_compare
258 {
259 public:
260 /* Return true if two operands are equal. The flags fields can be used
261 to specify OEP flags described in tree-core.h. */
262 virtual bool operand_equal_p (const_tree, const_tree, unsigned int flags);
263
264 /* Generate a hash value for an expression. This can be used iteratively
265 by passing a previous result as the HSTATE argument. */
266 virtual void hash_operand (const_tree, inchash::hash &, unsigned flags);
267
268 protected:
269 /* Verify that when arguments (ARG0 and ARG1) are equal, then they have
270 an equal hash value. When the function knowns comparison return,
271 true is returned. Then RET is set to corresponding comparsion result. */
272 bool verify_hash_value (const_tree arg0, const_tree arg1, unsigned int flags,
273 bool *ret);
274 };
275
276 #endif // GCC_FOLD_CONST_H