gcc/fold-const.h

   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_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 tree int_const_binop (enum tree_code, const_tree, const_tree, int = 1);
 130 #define build_fold_addr_expr(T)\
 131         build_fold_addr_expr_loc (UNKNOWN_LOCATION, (T))
 132 extern tree build_fold_addr_expr_loc (location_t, tree);
 133 #define build_fold_addr_expr_with_type(T,TYPE)\
 134         build_fold_addr_expr_with_type_loc (UNKNOWN_LOCATION, (T), TYPE)
 135 extern tree build_fold_addr_expr_with_type_loc (location_t, tree, tree);
 136 extern tree fold_build_cleanup_point_expr (tree type, tree expr);
 137 #define build_fold_indirect_ref(T)\
 138         build_fold_indirect_ref_loc (UNKNOWN_LOCATION, T)
 139 extern tree build_fold_indirect_ref_loc (location_t, tree);
 140 #define fold_indirect_ref(T)\
 141         fold_indirect_ref_loc (UNKNOWN_LOCATION, T)
 142 extern tree fold_indirect_ref_loc (location_t, tree);
 143 extern tree build_simple_mem_ref_loc (location_t, tree);
 144 #define build_simple_mem_ref(T)\
 145         build_simple_mem_ref_loc (UNKNOWN_LOCATION, T)
 146 extern poly_offset_int mem_ref_offset (const_tree);
 147 extern tree build_invariant_address (tree, tree, poly_int64);
 148 extern tree constant_boolean_node (bool, tree);
 149 extern tree div_if_zero_remainder (const_tree, const_tree);
 150
 151 extern bool tree_swap_operands_p (const_tree, const_tree);
 152 extern enum tree_code swap_tree_comparison (enum tree_code);
 153
 154 extern bool ptr_difference_const (tree, tree, poly_int64_pod *);
 155 extern enum tree_code invert_tree_comparison (enum tree_code, bool);
 156 extern bool inverse_conditions_p (const_tree, const_tree);
 157
 158 extern bool tree_unary_nonzero_warnv_p (enum tree_code, tree, tree, bool *);
 159 extern bool tree_binary_nonzero_warnv_p (enum tree_code, tree, tree, tree op1,
 160                                          bool *);
 161 extern bool tree_single_nonzero_warnv_p (tree, bool *);
 162 extern bool tree_unary_nonnegative_warnv_p (enum tree_code, tree, tree,
 163                                             bool *, int);
 164 extern bool tree_binary_nonnegative_warnv_p (enum tree_code, tree, tree, tree,
 165                                              bool *, int);
 166 extern bool tree_single_nonnegative_warnv_p (tree, bool *, int);
 167 extern bool tree_call_nonnegative_warnv_p (tree, combined_fn, tree, tree,
 168                                            bool *, int);
 169
 170 extern bool integer_valued_real_unary_p (tree_code, tree, int);
 171 extern bool integer_valued_real_binary_p (tree_code, tree, tree, int);
 172 extern bool integer_valued_real_call_p (combined_fn, tree, tree, int);
 173 extern bool integer_valued_real_single_p (tree, int);
 174 extern bool integer_valued_real_p (tree, int = 0);
 175
 176 extern bool fold_real_zero_addition_p (const_tree, const_tree, const_tree,
 177                                        int);
 178 extern tree combine_comparisons (location_t, enum tree_code, enum tree_code,
 179                                  enum tree_code, tree, tree, tree);
 180 extern void debug_fold_checksum (const_tree);
 181 extern bool may_negate_without_overflow_p (const_tree);
 182 #define round_up(T,N) round_up_loc (UNKNOWN_LOCATION, T, N)
 183 extern tree round_up_loc (location_t, tree, unsigned int);
 184 #define round_down(T,N) round_down_loc (UNKNOWN_LOCATION, T, N)
 185 extern tree round_down_loc (location_t, tree, int);
 186 extern tree size_int_kind (poly_int64, enum size_type_kind);
 187 #define size_binop(CODE,T1,T2)\
 188    size_binop_loc (UNKNOWN_LOCATION, CODE, T1, T2)
 189 extern tree size_binop_loc (location_t, enum tree_code, tree, tree);
 190 #define size_diffop(T1,T2)\
 191    size_diffop_loc (UNKNOWN_LOCATION, T1, T2)
 192 extern tree size_diffop_loc (location_t, tree, tree);
 193
 194 /* Return an expr equal to X but certainly not valid as an lvalue.  */
 195 #define non_lvalue(T) non_lvalue_loc (UNKNOWN_LOCATION, T)
 196 extern tree non_lvalue_loc (location_t, tree);
 197
 198 extern bool tree_expr_nonzero_p (tree);
 199 extern bool tree_expr_nonnegative_p (tree);
 200 extern bool tree_expr_nonnegative_warnv_p (tree, bool *, int = 0);
 201 extern bool tree_expr_finite_p (const_tree);
 202 extern bool tree_expr_infinite_p (const_tree);
 203 extern bool tree_expr_maybe_infinite_p (const_tree);
 204 extern bool tree_expr_signaling_nan_p (const_tree);
 205 extern bool tree_expr_maybe_signaling_nan_p (const_tree);
 206 extern bool tree_expr_nan_p (const_tree);
 207 extern bool tree_expr_maybe_nan_p (const_tree);
 208 extern bool tree_expr_maybe_real_minus_zero_p (const_tree);
 209 extern tree make_range (tree, int *, tree *, tree *, bool *);
 210 extern tree make_range_step (location_t, enum tree_code, tree, tree, tree,
 211                              tree *, tree *, int *, bool *);
 212 extern tree range_check_type (tree);
 213 extern tree build_range_check (location_t, tree, tree, int, tree, tree);
 214 extern bool merge_ranges (int *, tree *, tree *, int, tree, tree, int,
 215                           tree, tree);
 216 extern tree sign_bit_p (tree, const_tree);
 217 extern bool simple_condition_p (tree);
 218 extern tree exact_inverse (tree, tree);
 219 extern bool expr_not_equal_to (tree t, const wide_int &);
 220 extern tree const_unop (enum tree_code, tree, tree);
 221 extern tree const_binop (enum tree_code, tree, tree, tree);
 222 extern bool negate_mathfn_p (combined_fn);
 223 extern const char *getbyterep (tree, unsigned HOST_WIDE_INT *);
 224 extern const char *c_getstr (tree);
 225 extern wide_int tree_nonzero_bits (const_tree);
 226 extern int address_compare (tree_code, tree, tree, tree, tree &, tree &,
 227                             poly_int64 &, poly_int64 &, bool);
 228 extern tree ctor_single_nonzero_element (const_tree);
 229
 230 /* Return OFF converted to a pointer offset type suitable as offset for
 231    POINTER_PLUS_EXPR.  Use location LOC for this conversion.  */
 232 extern tree convert_to_ptrofftype_loc (location_t loc, tree off);
 233
 234 #define convert_to_ptrofftype(t) convert_to_ptrofftype_loc (UNKNOWN_LOCATION, t)
 235
 236 /* Build and fold a POINTER_PLUS_EXPR at LOC offsetting PTR by OFF.  */
 237 extern tree fold_build_pointer_plus_loc (location_t loc, tree ptr, tree off);
 238
 239 #define fold_build_pointer_plus(p,o) \
 240         fold_build_pointer_plus_loc (UNKNOWN_LOCATION, p, o)
 241
 242 /* Build and fold a POINTER_PLUS_EXPR at LOC offsetting PTR by OFF.  */
 243 extern tree fold_build_pointer_plus_hwi_loc (location_t loc, tree ptr, HOST_WIDE_INT off);
 244
 245 #define fold_build_pointer_plus_hwi(p,o) \
 246         fold_build_pointer_plus_hwi_loc (UNKNOWN_LOCATION, p, o)
 247
 248 extern tree_code minmax_from_comparison (tree_code, tree, tree,
 249                                          tree, tree);
 250
 251 /* In gimple-fold.cc.  */
 252 extern void clear_type_padding_in_mask (tree, unsigned char *);
 253 extern bool clear_padding_type_may_have_padding_p (tree);
 254 extern bool arith_overflowed_p (enum tree_code, const_tree, const_tree,
 255                                 const_tree);
 256
 257 /* Class used to compare gimple operands.  */
 258
 259 class operand_compare
 260 {
 261 public:
 262   /* Return true if two operands are equal.  The flags fields can be used
 263      to specify OEP flags described in tree-core.h.  */
 264   virtual bool operand_equal_p (const_tree, const_tree, unsigned int flags);
 265
 266   /* Generate a hash value for an expression.  This can be used iteratively
 267      by passing a previous result as the HSTATE argument.  */
 268   virtual void hash_operand (const_tree, inchash::hash &, unsigned flags);
 269
 270 protected:
 271   /* Verify that when arguments (ARG0 and ARG1) are equal, then they have
 272      an equal hash value.  When the function knowns comparison return,
 273      true is returned.  Then RET is set to corresponding comparsion result.  */
 274   bool verify_hash_value (const_tree arg0, const_tree arg1, unsigned int flags,
 275                           bool *ret);
 276 };
 277
 278 #endif // GCC_FOLD_CONST_H