[RS6000] PR79144, cmpstrnsi optimization breaks glibc
[official-gcc.git] / gcc / tree-vrp.h
blob4fed978d0aa204579e20bad01faf687e1955b6db
1 /* Support routines for Value Range Propagation (VRP).
2 Copyright (C) 2016-2017 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3, or (at your option)
9 any later version.
11 GCC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
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/>. */
20 /* Type of value ranges. See value_range_d In tree-vrp.c for a
21 description of these types. */
22 enum value_range_type { VR_UNDEFINED, VR_RANGE,
23 VR_ANTI_RANGE, VR_VARYING, VR_LAST };
25 /* Range of values that can be associated with an SSA_NAME after VRP
26 has executed. */
27 struct GTY(()) value_range
29 /* Lattice value represented by this range. */
30 enum value_range_type type;
32 /* Minimum and maximum values represented by this range. These
33 values should be interpreted as follows:
35 - If TYPE is VR_UNDEFINED or VR_VARYING then MIN and MAX must
36 be NULL.
38 - If TYPE == VR_RANGE then MIN holds the minimum value and
39 MAX holds the maximum value of the range [MIN, MAX].
41 - If TYPE == ANTI_RANGE the variable is known to NOT
42 take any values in the range [MIN, MAX]. */
43 tree min;
44 tree max;
46 /* Set of SSA names whose value ranges are equivalent to this one.
47 This set is only valid when TYPE is VR_RANGE or VR_ANTI_RANGE. */
48 bitmap equiv;
51 extern void vrp_intersect_ranges (value_range *vr0, value_range *vr1);
52 extern void vrp_meet (value_range *vr0, const value_range *vr1);
53 extern void dump_value_range (FILE *, const value_range *);
54 extern void extract_range_from_unary_expr (value_range *vr,
55 enum tree_code code,
56 tree type,
57 value_range *vr0_,
58 tree op0_type);