src/mesa/drivers/dri/i965/brw_fs_live_variables.h

   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 #include "brw_fs.h"
  29 #include "util/bitset.h"
  30
  31 struct cfg_t;
  32
  33 namespace brw {
  34
  35 struct block_data {
  36    /**
  37     * Which variables are defined before being used in the block.
  38     *
  39     * Note that for our purposes, "defined" means unconditionally, completely
  40     * defined.
  41     */
  42    BITSET_WORD *def;
  43
  44    /**
  45     * Which variables are used before being defined in the block.
  46     */
  47    BITSET_WORD *use;
  48
  49    /** Which defs reach the entry point of the block. */
  50    BITSET_WORD *livein;
  51
  52    /** Which defs reach the exit point of the block. */
  53    BITSET_WORD *liveout;
  54
  55    BITSET_WORD flag_def[1];
  56    BITSET_WORD flag_use[1];
  57    BITSET_WORD flag_livein[1];
  58    BITSET_WORD flag_liveout[1];
  59 };
  60
  61 class fs_live_variables {
  62 public:
  63    DECLARE_RALLOC_CXX_OPERATORS(fs_live_variables)
  64
  65    fs_live_variables(fs_visitor *v, const cfg_t *cfg);
  66    ~fs_live_variables();
  67
  68    bool vars_interfere(int a, int b);
  69    int var_from_reg(const fs_reg &reg) const
  70    {
  71       return var_from_vgrf[reg.nr] + reg.offset / REG_SIZE;
  72    }
  73
  74    /** Map from virtual GRF number to index in block_data arrays. */
  75    int *var_from_vgrf;
  76
  77    /**
  78     * Map from any index in block_data to the virtual GRF containing it.
  79     *
  80     * For alloc.sizes of [1, 2, 3], vgrf_from_var would contain
  81     * [0, 1, 1, 2, 2, 2].
  82     */
  83    int *vgrf_from_var;
  84
  85    int num_vars;
  86    int num_vgrfs;
  87    int bitset_words;
  88
  89    /** @{
  90     * Final computed live ranges for each var (each component of each virtual
  91     * GRF).
  92     */
  93    int *start;
  94    int *end;
  95    /** @} */
  96
  97    /** Per-basic-block information on live variables */
  98    struct block_data *block_data;
  99
 100 protected:
 101    void setup_def_use();
 102    void setup_one_read(struct block_data *bd, fs_inst *inst, int ip,
 103                        const fs_reg &reg);
 104    void setup_one_write(struct block_data *bd, fs_inst *inst, int ip,
 105                         const fs_reg &reg);
 106    void compute_live_variables();
 107    void compute_start_end();
 108
 109    fs_visitor *v;
 110    const cfg_t *cfg;
 111    void *mem_ctx;
 112
 113 };
 114
 115 } /* namespace brw */