src/intel/compiler/brw_vec4_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 "util/bitset.h"
  29 #include "brw_vec4.h"
  30
  31 namespace brw {
  32
  33 struct block_data {
  34    /**
  35     * Which variables are defined before being used in the block.
  36     *
  37     * Note that for our purposes, "defined" means unconditionally, completely
  38     * defined.
  39     */
  40    BITSET_WORD *def;
  41
  42    /**
  43     * Which variables are used before being defined in the block.
  44     */
  45    BITSET_WORD *use;
  46
  47    /** Which defs reach the entry point of the block. */
  48    BITSET_WORD *livein;
  49
  50    /** Which defs reach the exit point of the block. */
  51    BITSET_WORD *liveout;
  52
  53    BITSET_WORD flag_def[1];
  54    BITSET_WORD flag_use[1];
  55    BITSET_WORD flag_livein[1];
  56    BITSET_WORD flag_liveout[1];
  57 };
  58
  59 class vec4_live_variables {
  60 public:
  61    DECLARE_RALLOC_CXX_OPERATORS(vec4_live_variables)
  62
  63    vec4_live_variables(const simple_allocator &alloc, cfg_t *cfg);
  64    ~vec4_live_variables();
  65
  66    int num_vars;
  67    int bitset_words;
  68
  69    /** Per-basic-block information on live variables */
  70    struct block_data *block_data;
  71
  72 protected:
  73    void setup_def_use();
  74    void compute_live_variables();
  75
  76    const simple_allocator &alloc;
  77    cfg_t *cfg;
  78    void *mem_ctx;
  79 };
  80
  81 /* Returns the variable index for the k-th dword of the c-th component of
  82  * register reg.
  83  */
  84 inline unsigned
  85 var_from_reg(const simple_allocator &alloc, const src_reg &reg,
  86              unsigned c = 0, unsigned k = 0)
  87 {
  88    assert(reg.file == VGRF && reg.nr < alloc.count && c < 4);
  89    const unsigned csize = DIV_ROUND_UP(type_sz(reg.type), 4);
  90    unsigned result =
  91       8 * (alloc.offsets[reg.nr] + reg.offset / REG_SIZE) +
  92       (BRW_GET_SWZ(reg.swizzle, c) + k / csize * 4) * csize + k % csize;
  93    /* Do not exceed the limit for this register */
  94    assert(result < 8 * (alloc.offsets[reg.nr] + alloc.sizes[reg.nr]));
  95    return result;
  96 }
  97
  98 inline unsigned
  99 var_from_reg(const simple_allocator &alloc, const dst_reg &reg,
 100              unsigned c = 0, unsigned k = 0)
 101 {
 102    assert(reg.file == VGRF && reg.nr < alloc.count && c < 4);
 103    const unsigned csize = DIV_ROUND_UP(type_sz(reg.type), 4);
 104    unsigned result =
 105       8 * (alloc.offsets[reg.nr] + reg.offset / REG_SIZE) +
 106       (c + k / csize * 4) * csize + k % csize;
 107    /* Do not exceed the limit for this register */
 108    assert(result < 8 * (alloc.offsets[reg.nr] + alloc.sizes[reg.nr]));
 109    return result;
 110 }
 111
 112 } /* namespace brw */