1/*
2 * Copyright © 2012 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 *    Eric Anholt <eric@anholt.net>
25 *
26 */
27
28#ifndef BRW_FS_LIVE_VARIABLES_H
29#define BRW_FS_LIVE_VARIABLES_H
30
31#include "brw_fs.h"
32#include "util/bitset.h"
33
34struct cfg_t;
35
36namespace brw {
37
38struct block_data {
39   /**
40    * Which variables are defined before being used in the block.
41    *
42    * Note that for our purposes, "defined" means unconditionally, completely
43    * defined.
44    */
45   BITSET_WORD *def;
46
47   /**
48    * Which variables are used before being defined in the block.
49    */
50   BITSET_WORD *use;
51
52   /** Which defs reach the entry point of the block. */
53   BITSET_WORD *livein;
54
55   /** Which defs reach the exit point of the block. */
56   BITSET_WORD *liveout;
57
58   /**
59    * Variables such that the entry point of the block may be reached from any
60    * of their definitions.
61    */
62   BITSET_WORD *defin;
63
64   /**
65    * Variables such that the exit point of the block may be reached from any
66    * of their definitions.
67    */
68   BITSET_WORD *defout;
69
70   BITSET_WORD flag_def[1];
71   BITSET_WORD flag_use[1];
72   BITSET_WORD flag_livein[1];
73   BITSET_WORD flag_liveout[1];
74};
75
76class fs_live_variables {
77public:
78   DECLARE_RALLOC_CXX_OPERATORS(fs_live_variables)
79
80   fs_live_variables(fs_visitor *v, const cfg_t *cfg);
81   ~fs_live_variables();
82
83   bool vars_interfere(int a, int b);
84   int var_from_reg(const fs_reg &reg) const
85   {
86      return var_from_vgrf[reg.nr] + reg.offset / REG_SIZE;
87   }
88
89   /** Map from virtual GRF number to index in block_data arrays. */
90   int *var_from_vgrf;
91
92   /**
93    * Map from any index in block_data to the virtual GRF containing it.
94    *
95    * For alloc.sizes of [1, 2, 3], vgrf_from_var would contain
96    * [0, 1, 1, 2, 2, 2].
97    */
98   int *vgrf_from_var;
99
100   int num_vars;
101   int num_vgrfs;
102   int bitset_words;
103
104   /** @{
105    * Final computed live ranges for each var (each component of each virtual
106    * GRF).
107    */
108   int *start;
109   int *end;
110   /** @} */
111
112   /** Per-basic-block information on live variables */
113   struct block_data *block_data;
114
115protected:
116   void setup_def_use();
117   void setup_one_read(struct block_data *bd, fs_inst *inst, int ip,
118                       const fs_reg &reg);
119   void setup_one_write(struct block_data *bd, fs_inst *inst, int ip,
120                        const fs_reg &reg);
121   void compute_live_variables();
122   void compute_start_end();
123
124   fs_visitor *v;
125   const cfg_t *cfg;
126   void *mem_ctx;
127
128};
129
130} /* namespace brw */
131
132#endif /* BRW_FS_LIVE_VARIABLES_H */
133