gcc/fold-const.h

   1 /* Fold a constant sub-tree into a single node for C-compiler
   2    Copyright (C) 1987-2025 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_ignored_result (tree);
  96 extern tree fold_abs_const (tree, tree);
  97 extern tree fold_indirect_ref_1 (location_t, tree, tree);
  98 extern void fold_defer_overflow_warnings (void);
  99 extern void fold_undefer_overflow_warnings (bool, const gimple *, int);
 100 extern void fold_undefer_and_ignore_overflow_warnings (void);
 101 extern bool fold_deferring_overflow_warnings_p (void);
 102 extern void fold_overflow_warning (const char*, enum warn_strict_overflow_code);
 103 extern enum tree_code fold_div_compare (enum tree_code, tree, tree,
 104                                         tree *, tree *, bool *);
 105 extern bool operand_equal_p (const_tree, const_tree, unsigned int flags = 0);
 106 extern bool multiple_of_p (tree, const_tree, const_tree, bool = true);
 107 #define omit_one_operand(T1,T2,T3)\
 108    omit_one_operand_loc (UNKNOWN_LOCATION, T1, T2, T3)
 109 extern tree omit_one_operand_loc (location_t, tree, tree, tree);
 110 #define omit_two_operands(T1,T2,T3,T4)\
 111    omit_two_operands_loc (UNKNOWN_LOCATION, T1, T2, T3, T4)
 112 extern tree omit_two_operands_loc (location_t, tree, tree, tree, tree);
 113 #define invert_truthvalue(T)\
 114    invert_truthvalue_loc (UNKNOWN_LOCATION, T)
 115 extern tree invert_truthvalue_loc (location_t, tree);
 116 extern tree fold_unary_to_constant (enum tree_code, tree, tree);
 117 extern tree fold_binary_to_constant (enum tree_code, tree, tree, tree);
 118 extern tree fold_bit_and_mask (tree, tree, enum tree_code,
 119                                tree, enum tree_code, tree, tree,
 120                                tree, enum tree_code, tree, tree, tree *);
 121 extern tree fold_read_from_constant_string (tree);
 122 extern tree fold_read_from_vector (tree, poly_uint64);
 123 #if GCC_VEC_PERN_INDICES_H
 124 extern tree fold_vec_perm (tree, tree, tree, const vec_perm_indices &);
 125 #endif
 126 extern bool wide_int_binop (wide_int &res, enum tree_code,
 127                             const wide_int &arg1, const wide_int &arg2,
 128                             signop, wi::overflow_type *);
 129 extern bool poly_int_binop (poly_wide_int &res, enum tree_code,
 130                             const_tree, const_tree, signop,
 131                             wi::overflow_type *);
 132 extern tree int_const_binop (enum tree_code, const_tree, const_tree, int = 1);
 133 #define build_fold_addr_expr(T)\
 134         build_fold_addr_expr_loc (UNKNOWN_LOCATION, (T))
 135 extern tree build_fold_addr_expr_loc (location_t, tree);
 136 #define build_fold_addr_expr_with_type(T,TYPE)\
 137         build_fold_addr_expr_with_type_loc (UNKNOWN_LOCATION, (T), TYPE)
 138 extern tree build_fold_addr_expr_with_type_loc (location_t, tree, tree);
 139 extern tree fold_build_cleanup_point_expr (tree type, tree expr);
 140 #define build_fold_indirect_ref(T)\
 141         build_fold_indirect_ref_loc (UNKNOWN_LOCATION, T)
 142 extern tree build_fold_indirect_ref_loc (location_t, tree);
 143 #define fold_indirect_ref(T)\
 144         fold_indirect_ref_loc (UNKNOWN_LOCATION, T)
 145 extern tree fold_indirect_ref_loc (location_t, tree);
 146 extern tree build_simple_mem_ref_loc (location_t, tree);
 147 #define build_simple_mem_ref(T)\
 148         build_simple_mem_ref_loc (UNKNOWN_LOCATION, T)
 149 extern poly_offset_int mem_ref_offset (const_tree);
 150 extern tree build_invariant_address (tree, tree, poly_int64);
 151 extern tree constant_boolean_node (bool, tree);
 152 extern tree div_if_zero_remainder (const_tree, const_tree);
 153
 154 extern bool tree_swap_operands_p (const_tree, const_tree);
 155 extern enum tree_code swap_tree_comparison (enum tree_code);
 156
 157 extern bool ptr_difference_const (tree, tree, poly_int64 *);
 158 extern enum tree_code invert_tree_comparison (enum tree_code, bool);
 159 extern bool inverse_conditions_p (const_tree, const_tree);
 160
 161 extern bool tree_unary_nonzero_warnv_p (enum tree_code, tree, tree, bool *);
 162 extern bool tree_binary_nonzero_warnv_p (enum tree_code, tree, tree, tree op1,
 163                                          bool *);
 164 extern bool tree_single_nonzero_warnv_p (tree, bool *);
 165 extern bool tree_unary_nonnegative_warnv_p (enum tree_code, tree, tree,
 166                                             bool *, int);
 167 extern bool tree_binary_nonnegative_warnv_p (enum tree_code, tree, tree, tree,
 168                                              bool *, int);
 169 extern bool tree_single_nonnegative_warnv_p (tree, bool *, int);
 170 extern bool tree_call_nonnegative_warnv_p (tree, combined_fn, tree, tree,
 171                                            bool *, int);
 172
 173 extern bool integer_valued_real_unary_p (tree_code, tree, int);
 174 extern bool integer_valued_real_binary_p (tree_code, tree, tree, int);
 175 extern bool integer_valued_real_call_p (combined_fn, tree, tree, int);
 176 extern bool integer_valued_real_single_p (tree, int);
 177 extern bool integer_valued_real_p (tree, int = 0);
 178
 179 extern bool fold_real_zero_addition_p (const_tree, const_tree, const_tree,
 180                                        int);
 181 extern tree combine_comparisons (location_t, enum tree_code, enum tree_code,
 182                                  enum tree_code, tree, tree, tree);
 183 extern void debug_fold_checksum (const_tree);
 184 extern bool may_negate_without_overflow_p (const_tree);
 185 #define round_up(T,N) round_up_loc (UNKNOWN_LOCATION, T, N)
 186 extern tree round_up_loc (location_t, tree, unsigned int);
 187 #define round_down(T,N) round_down_loc (UNKNOWN_LOCATION, T, N)
 188 extern tree round_down_loc (location_t, tree, int);
 189 extern tree size_int_kind (poly_int64, enum size_type_kind);
 190 #define size_binop(CODE,T1,T2)\
 191    size_binop_loc (UNKNOWN_LOCATION, CODE, T1, T2)
 192 extern tree size_binop_loc (location_t, enum tree_code, tree, tree);
 193 #define size_diffop(T1,T2)\
 194    size_diffop_loc (UNKNOWN_LOCATION, T1, T2)
 195 extern tree size_diffop_loc (location_t, tree, tree);
 196
 197 /* Return an expr equal to X but certainly not valid as an lvalue.  */
 198 #define non_lvalue(T) non_lvalue_loc (UNKNOWN_LOCATION, T)
 199 extern tree non_lvalue_loc (location_t, tree);
 200
 201 extern bool tree_expr_nonzero_p (tree);
 202 extern bool tree_expr_nonnegative_p (tree);
 203 extern bool tree_expr_nonnegative_warnv_p (tree, bool *, int = 0);
 204 extern bool tree_expr_finite_p (const_tree);
 205 extern bool tree_expr_infinite_p (const_tree);
 206 extern bool tree_expr_maybe_infinite_p (const_tree);
 207 extern bool tree_expr_signaling_nan_p (const_tree);
 208 extern bool tree_expr_maybe_signaling_nan_p (const_tree);
 209 extern bool tree_expr_nan_p (const_tree);
 210 extern bool tree_expr_maybe_nan_p (const_tree);
 211 extern bool tree_expr_maybe_real_minus_zero_p (const_tree);
 212 extern tree make_range (tree, int *, tree *, tree *, bool *);
 213 extern tree make_range_step (location_t, enum tree_code, tree, tree, tree,
 214                              tree *, tree *, int *, bool *);
 215 extern tree range_check_type (tree);
 216 extern tree build_range_check (location_t, tree, tree, int, tree, tree);
 217 extern bool merge_ranges (int *, tree *, tree *, int, tree, tree, int,
 218                           tree, tree);
 219 extern tree sign_bit_p (tree, const_tree);
 220 extern bool simple_condition_p (tree);
 221 extern tree exact_inverse (tree, tree);
 222 extern bool expr_not_equal_to (tree t, const wide_int &);
 223 extern tree const_unop (enum tree_code, tree, tree);
 224 extern tree vector_const_binop (enum tree_code, tree, tree,
 225                                 tree (*) (enum tree_code, tree, tree));
 226 extern tree const_binop (enum tree_code, tree, tree, tree);
 227 extern bool negate_mathfn_p (combined_fn);
 228 extern const char *getbyterep (tree, unsigned HOST_WIDE_INT *);
 229 extern const char *c_getstr (tree);
 230 extern wide_int tree_nonzero_bits (const_tree);
 231 extern int address_compare (tree_code, tree, tree, tree, tree &, tree &,
 232                             poly_int64 &, poly_int64 &, bool);
 233 extern tree ctor_single_nonzero_element (const_tree);
 234
 235 /* Return OFF converted to a pointer offset type suitable as offset for
 236    POINTER_PLUS_EXPR.  Use location LOC for this conversion.  */
 237 extern tree convert_to_ptrofftype_loc (location_t loc, tree off);
 238
 239 #define convert_to_ptrofftype(t) convert_to_ptrofftype_loc (UNKNOWN_LOCATION, t)
 240
 241 /* Build and fold a POINTER_PLUS_EXPR at LOC offsetting PTR by OFF.  */
 242 extern tree fold_build_pointer_plus_loc (location_t loc, tree ptr, tree off);
 243
 244 #define fold_build_pointer_plus(p,o) \
 245         fold_build_pointer_plus_loc (UNKNOWN_LOCATION, p, o)
 246
 247 /* Build and fold a POINTER_PLUS_EXPR at LOC offsetting PTR by OFF.  */
 248 extern tree fold_build_pointer_plus_hwi_loc (location_t loc, tree ptr, HOST_WIDE_INT off);
 249
 250 #define fold_build_pointer_plus_hwi(p,o) \
 251         fold_build_pointer_plus_hwi_loc (UNKNOWN_LOCATION, p, o)
 252
 253 extern tree_code minmax_from_comparison (tree_code, tree, tree,
 254                                          tree, tree);
 255
 256 extern tree make_bit_field_ref (location_t, tree, tree, tree,
 257                                 HOST_WIDE_INT, poly_int64, int, int);
 258
 259 /* In gimple-fold.cc.  */
 260 extern void clear_type_padding_in_mask (tree, unsigned char *);
 261 extern bool clear_padding_type_may_have_padding_p (tree);
 262 extern bool arith_overflowed_p (enum tree_code, const_tree, const_tree,
 263                                 const_tree);
 264 extern tree fold_truth_andor_for_ifcombine (enum tree_code, tree,
 265                                             location_t, enum tree_code,
 266                                             tree, tree,
 267                                             location_t, enum tree_code,
 268                                             tree, tree,
 269                                             tree *);
 270
 271
 272 /* Class used to compare gimple operands.  */
 273
 274 class operand_compare
 275 {
 276 public:
 277   /* Return true if two operands are equal.  The flags fields can be used
 278      to specify OEP flags described in tree-core.h.  */
 279   virtual bool operand_equal_p (const_tree, const_tree, unsigned int flags);
 280
 281   /* Generate a hash value for an expression.  This can be used iteratively
 282      by passing a previous result as the HSTATE argument.  */
 283   virtual void hash_operand (const_tree, inchash::hash &, unsigned flags);
 284
 285 protected:
 286   /* Verify that when arguments (ARG0 and ARG1) are equal, then they have
 287      an equal hash value.  When the function knowns comparison return,
 288      true is returned.  Then RET is set to corresponding comparsion result.  */
 289   bool verify_hash_value (const_tree arg0, const_tree arg1, unsigned int flags,
 290                           bool *ret);
 291
 292 private:
 293   /* Return true if two operands are equal.  The flags fields can be used
 294      to specify OEP flags described in tree-core.h.  */
 295   bool operand_equal_p (tree, const_tree, tree, const_tree,
 296                         unsigned int flags);
 297 };
 298
 299 #endif // GCC_FOLD_CONST_H