xref: /aosp_15_r20/external/mesa3d/src/gallium/drivers/etnaviv/etnaviv_nir_lower_ubo_to_uniform.c (revision 6104692788411f58d303aa86923a9ff6ecaded22)
1 /*
2  * Copyright (c) 2020 Etnaviv Project
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, sub license,
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
12  * next paragraph) shall be included in all copies or substantial portions
13  * of the 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 NON-INFRINGEMENT. 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
21  * DEALINGS IN THE SOFTWARE.
22  *
23  * Authors:
24  *    Christian Gmeiner <[email protected]>
25  */
26 
27 #include "etnaviv_nir.h"
28 
29 /*
30  * Pass to lower the load_ubo intrinsics for block 0 back to load_uniform intrinsics.
31  */
32 
33 static bool
is_const_ubo(const nir_instr * instr,const void * _data)34 is_const_ubo(const nir_instr *instr, const void *_data)
35 {
36    if (instr->type != nir_instr_type_intrinsic)
37       return false;
38 
39    nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
40    if (intr->intrinsic != nir_intrinsic_load_ubo)
41       return false;
42 
43    if (!nir_src_is_const(intr->src[0]) || !nir_src_is_const(intr->src[1]))
44       return false;
45 
46    const uint32_t block = nir_src_as_uint(intr->src[0]);
47    if (block > 0)
48       return false;
49 
50    return true;
51 }
52 
53 static nir_def *
lower_ubo_to_uniform(nir_builder * b,nir_instr * instr,void * _data)54 lower_ubo_to_uniform(nir_builder *b, nir_instr *instr, void *_data)
55 {
56    nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
57    b->cursor = nir_before_instr(instr);
58 
59    /* Undo the operations done in nir_lower_uniforms_to_ubo. */
60    nir_def *ubo_offset = intr->src[1].ssa;
61    nir_def *range_base = nir_imm_int(b, nir_intrinsic_range_base(intr));
62 
63    nir_def *uniform_offset =
64       nir_ushr_imm(b, nir_isub(b, ubo_offset, range_base), 4);
65 
66    nir_def *uniform =
67       nir_load_uniform(b, intr->num_components, intr->def.bit_size, uniform_offset,
68                        .base = nir_intrinsic_range_base(intr) / 16,
69                        .range = nir_intrinsic_range(intr) / 16,
70                        .dest_type = nir_type_float32);
71 
72 	nir_def_rewrite_uses(&intr->def, uniform);
73 
74    return uniform;
75 }
76 
77 bool
etna_nir_lower_ubo_to_uniform(nir_shader * shader)78 etna_nir_lower_ubo_to_uniform(nir_shader *shader)
79 {
80    return nir_shader_lower_instructions(shader,
81                                         is_const_ubo,
82                                         lower_ubo_to_uniform,
83                                         NULL);
84 
85 }
86