src/gallium/drivers/lima/ir/lima_nir_split_load_input.c

   1 /*
   2  * Copyright © 2019 Vasily Khoruzhick <anarsoul@gmail.com>
   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
  24 #include "nir.h"
  25 #include "nir_builder.h"
  26
  27 #include "lima_ir.h"
  28
  29 static bool
  30 lima_nir_split_load_input_block(nir_block *block, nir_builder *b)
  31 {
  32    bool progress = false;
  33
  34    nir_foreach_instr_safe(instr, block) {
  35       if (instr->type != nir_instr_type_alu)
  36          continue;
  37
  38       nir_alu_instr *alu = nir_instr_as_alu(instr);
  39       if (alu->op != nir_op_mov)
  40          continue;
  41
  42       if (!alu->dest.dest.is_ssa)
  43          continue;
  44
  45       if (!alu->src[0].src.is_ssa)
  46          continue;
  47
  48       nir_ssa_def *ssa = alu->src[0].src.ssa;
  49       if (ssa->parent_instr->type != nir_instr_type_intrinsic)
  50          continue;
  51
  52       nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(ssa->parent_instr);
  53       if (intrin->intrinsic != nir_intrinsic_load_input)
  54          continue;
  55
  56       uint8_t swizzle = alu->src[0].swizzle[0];
  57       int i;
  58
  59       for (i = 1; i < nir_dest_num_components(alu->dest.dest); i++)
  60          if (alu->src[0].swizzle[i] != (swizzle + i))
  61             break;
  62
  63       if (i != nir_dest_num_components(alu->dest.dest))
  64          continue;
  65
  66       b->cursor = nir_before_instr(&intrin->instr);
  67       nir_intrinsic_instr *new_intrin = nir_intrinsic_instr_create(
  68                                              b->shader,
  69                                              intrin->intrinsic);
  70       nir_ssa_dest_init(&new_intrin->instr, &new_intrin->dest,
  71                         nir_dest_num_components(alu->dest.dest),
  72                         ssa->bit_size,
  73                         NULL);
  74       new_intrin->num_components = nir_dest_num_components(alu->dest.dest);
  75       nir_intrinsic_set_base(new_intrin, nir_intrinsic_base(intrin));
  76       nir_intrinsic_set_component(new_intrin, nir_intrinsic_component(intrin) + swizzle);
  77       nir_intrinsic_set_type(new_intrin, nir_intrinsic_type(intrin));
  78
  79       /* offset */
  80       nir_src_copy(&new_intrin->src[0], &intrin->src[0], new_intrin);
  81
  82       nir_builder_instr_insert(b, &new_intrin->instr);
  83       nir_ssa_def_rewrite_uses(&alu->dest.dest.ssa,
  84                                nir_src_for_ssa(&new_intrin->dest.ssa));
  85       nir_instr_remove(&alu->instr);
  86       progress = true;
  87    }
  88
  89    return progress;
  90 }
  91
  92 static bool
  93 lima_nir_split_load_input_impl(nir_function_impl *impl)
  94 {
  95    bool progress = false;
  96    nir_builder builder;
  97    nir_builder_init(&builder, impl);
  98
  99    nir_foreach_block(block, impl) {
 100       progress |= lima_nir_split_load_input_block(block, &builder);
 101    }
 102
 103    nir_metadata_preserve(impl, nir_metadata_block_index |
 104                                nir_metadata_dominance);
 105    return progress;
 106 }
 107
 108 /* Replaces a single load of several packed varyings and number of movs with
 109  * a number of loads of smaller size
 110  */
 111 bool
 112 lima_nir_split_load_input(nir_shader *shader)
 113 {
 114    bool progress = false;
 115
 116    nir_foreach_function(function, shader) {
 117       if (function->impl)
 118          progress |= lima_nir_split_load_input_impl(function->impl);
 119    }
 120
 121    return progress;
 122 }
 123