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_ir_analysis.h"
32#include "brw_ir_fs.h"
33#include "util/bitset.h"
34
35struct cfg_t;
36struct backend_shader;
37
38namespace brw {
39
40class fs_live_variables {
41public:
42   struct block_data {
43      /**
44       * Which variables are defined before being used in the block.
45       *
46       * Note that for our purposes, "defined" means unconditionally, completely
47       * defined.
48       */
49      BITSET_WORD *def;
50
51      /**
52       * Which variables are used before being defined in the block.
53       */
54      BITSET_WORD *use;
55
56      /** Which defs reach the entry point of the block. */
57      BITSET_WORD *livein;
58
59      /** Which defs reach the exit point of the block. */
60      BITSET_WORD *liveout;
61
62      /**
63       * Variables such that the entry point of the block may be reached from any
64       * of their definitions.
65       */
66      BITSET_WORD *defin;
67
68      /**
69       * Variables such that the exit point of the block may be reached from any
70       * of their definitions.
71       */
72      BITSET_WORD *defout;
73
74      BITSET_WORD flag_def[1];
75      BITSET_WORD flag_use[1];
76      BITSET_WORD flag_livein[1];
77      BITSET_WORD flag_liveout[1];
78   };
79
80   fs_live_variables(const backend_shader *s);
81   ~fs_live_variables();
82
83   bool validate(const backend_shader *s) const;
84
85   analysis_dependency_class
86   dependency_class() const
87   {
88      return (DEPENDENCY_INSTRUCTION_IDENTITY |
89              DEPENDENCY_INSTRUCTION_DATA_FLOW |
90              DEPENDENCY_VARIABLES);
91   }
92
93   bool vars_interfere(int a, int b) const;
94   bool vgrfs_interfere(int a, int b) const;
95   int var_from_reg(const fs_reg &reg) const
96   {
97      return var_from_vgrf[reg.nr] + reg.offset / REG_SIZE;
98   }
99
100   /** Map from virtual GRF number to index in block_data arrays. */
101   int *var_from_vgrf;
102
103   /**
104    * Map from any index in block_data to the virtual GRF containing it.
105    *
106    * For alloc.sizes of [1, 2, 3], vgrf_from_var would contain
107    * [0, 1, 1, 2, 2, 2].
108    */
109   int *vgrf_from_var;
110
111   int num_vars;
112   int num_vgrfs;
113   int bitset_words;
114
115   /** @{
116    * Final computed live ranges for each var (each component of each virtual
117    * GRF).
118    */
119   int *start;
120   int *end;
121   /** @} */
122
123   /** @{
124    * Final computed live ranges for each VGRF.
125    */
126   int *vgrf_start;
127   int *vgrf_end;
128   /** @} */
129
130   /** Per-basic-block information on live variables */
131   struct block_data *block_data;
132
133protected:
134   void setup_def_use();
135   void setup_one_read(struct block_data *bd, int ip, const fs_reg &reg);
136   void setup_one_write(struct block_data *bd, fs_inst *inst, int ip,
137                        const fs_reg &reg);
138   void compute_live_variables();
139   void compute_start_end();
140
141   const struct intel_device_info *devinfo;
142   const cfg_t *cfg;
143   void *mem_ctx;
144};
145
146} /* namespace brw */
147
148#endif /* BRW_FS_LIVE_VARIABLES_H */
149