1 | /* Alignment-related classes. |
2 | Copyright (C) 2018-2023 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 | /* Align flags tuple with alignment in log form and with a maximum skip. */ |
21 | |
22 | struct align_flags_tuple |
23 | { |
24 | /* Values of the -falign-* flags: how much to align labels in code. |
25 | log is "align to 2^log" (so 0 means no alignment). |
26 | maxskip is the maximum allowed amount of padding to insert. */ |
27 | int log; |
28 | int maxskip; |
29 | |
30 | /* Normalize filled values so that maxskip is not bigger than 1 << log. */ |
31 | void normalize () |
32 | { |
33 | int n = (1 << log); |
34 | if (maxskip > n) |
35 | maxskip = n - 1; |
36 | } |
37 | |
38 | /* Return original value of an alignment flag. */ |
39 | int get_value () |
40 | { |
41 | return maxskip + 1; |
42 | } |
43 | }; |
44 | |
45 | /* Alignment flags is structure used as value of -align-* options. |
46 | It's used in target-dependant code. */ |
47 | |
48 | class align_flags |
49 | { |
50 | public: |
51 | /* Default constructor. */ |
52 | align_flags (int log0 = 0, int maxskip0 = 0, int log1 = 0, int maxskip1 = 0) |
53 | { |
54 | levels[0].log = log0; |
55 | levels[0].maxskip = maxskip0; |
56 | levels[1].log = log1; |
57 | levels[1].maxskip = maxskip1; |
58 | normalize (); |
59 | } |
60 | |
61 | /* Normalize both components of align_flags. */ |
62 | void normalize () |
63 | { |
64 | for (unsigned i = 0; i < 2; i++) |
65 | levels[i].normalize (); |
66 | } |
67 | |
68 | /* Get alignment that is common bigger alignment of alignments F0 and F1. */ |
69 | static align_flags max (const align_flags f0, const align_flags f1) |
70 | { |
71 | int log0 = MAX (f0.levels[0].log, f1.levels[0].log); |
72 | int maxskip0 = MAX (f0.levels[0].maxskip, f1.levels[0].maxskip); |
73 | int log1 = MAX (f0.levels[1].log, f1.levels[1].log); |
74 | int maxskip1 = MAX (f0.levels[1].maxskip, f1.levels[1].maxskip); |
75 | return align_flags (log0, maxskip0, log1, maxskip1); |
76 | } |
77 | |
78 | align_flags_tuple levels[2]; |
79 | }; |
80 | |
81 | /* Define maximum supported code alignment. */ |
82 | #define MAX_CODE_ALIGN 16 |
83 | #define MAX_CODE_ALIGN_VALUE (1 << MAX_CODE_ALIGN) |
84 | |