src/panfrost/bifrost/bi_layout.c

   1 /*
   2  * Copyright (C) 2020 Collabora, Ltd.
   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 FROM,
  20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  */
  23
  24 #include "compiler.h"
  25
  26 /* The scheduler packs multiple instructions into a clause (grouped as bundle),
  27  * and the packing code takes in a clause and emits it to the wire. During
  28  * scheduling, we need to lay out the instructions (bundles) and constants
  29  * within the clause so constraints can be resolved during scheduling instead
  30  * of failing packing. These routines will help building clauses from
  31  * instructions so the scheduler can focus on the high-level algorithm, and
  32  * manipulating clause layouts.
  33  */
  34
  35 /* Helper to see if a bundle can be inserted. We must satisfy the invariant:
  36  *
  37  *      constant_count + bundle_count <= 13
  38  *
  39  * ...which is equivalent to the clause ending up with 8 or fewer quardwords.
  40  * Inserting a bundle increases bundle_count by one, and if it reads a unique
  41  * constant, it increases constant_count by one.
  42  */
  43
  44 bool
  45 bi_can_insert_bundle(bi_clause *clause, bool constant)
  46 {
  47         unsigned constant_count = clause->constant_count + (constant ? 1 : 0);
  48         unsigned bundle_count = clause->bundle_count + 1;
  49
  50         return (constant_count + bundle_count) <= 13;
  51 }