src/amd/vulkan/radv_nir_lower_ycbcr_textures.c - third_party/mesa - Git at Google

 /*
  * Copyright © 2017 Intel Corporation
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  * and/or sell copies of the Software, and to permit persons to whom the
  * Software is furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice (including the next
  * paragraph) shall be included in all copies or substantial portions of the
  * Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  * IN THE SOFTWARE.
  */

 #include "nir/nir.h"
 #include "nir/nir_builder.h"
 #include "nir/nir_vulkan.h"
 #include "radv_private.h"
 #include "radv_shader.h"
 #include "vk_format.h"

 struct ycbcr_state {
    nir_builder *builder;
    nir_ssa_def *image_size;
    nir_tex_instr *origin_tex;
    nir_deref_instr *tex_deref;
    const struct radv_sampler_ycbcr_conversion_state *conversion;
    bool unnormalized_coordinates;
 };

 static nir_ssa_def *
 get_texture_size(struct ycbcr_state *state, nir_deref_instr *texture)
 {
    nir_builder *b = state->builder;
    const struct glsl_type *type = texture->type;
    nir_tex_instr *tex = nir_tex_instr_create(b->shader, 1);

    tex->op = nir_texop_txs;
    tex->sampler_dim = glsl_get_sampler_dim(type);
    tex->is_array = glsl_sampler_type_is_array(type);
    tex->is_shadow = glsl_sampler_type_is_shadow(type);
    tex->dest_type = nir_type_int32;

    tex->src[0].src_type = nir_tex_src_texture_deref;
    tex->src[0].src = nir_src_for_ssa(&texture->dest.ssa);

    nir_ssa_dest_init(&tex->instr, &tex->dest, nir_tex_instr_dest_size(tex), 32, NULL);
    nir_builder_instr_insert(b, &tex->instr);

    state->builder->shader->info.uses_resource_info_query = true;

    return nir_i2f32(b, &tex->dest.ssa);
 }

 static nir_ssa_def *
 implicit_downsampled_coord(nir_builder *b, nir_ssa_def *value, nir_ssa_def *max_value,
                            int div_scale)
 {
    return nir_fadd(
       b, value,
       nir_fdiv(b, nir_imm_float(b, 1.0f), nir_fmul(b, nir_imm_float(b, div_scale), max_value)));
 }

 static nir_ssa_def *
 implicit_downsampled_coord_unnormalized(nir_builder *b, nir_ssa_def *value, int div_scale)
 {
    return nir_fadd(
       b, value,
       nir_imm_float(b, 1.0f / (float)div_scale));
 }

 static nir_ssa_def *
 implicit_downsampled_coords(struct ycbcr_state *state, nir_ssa_def *old_coords)
 {
    nir_builder *b = state->builder;
    const struct radv_sampler_ycbcr_conversion_state *conversion = state->conversion;
    nir_ssa_def *image_size = NULL;
    nir_ssa_def *comp[4] = {
       NULL,
    };
    enum pipe_video_chroma_format chroma_format =
       pipe_format_to_chroma_format(vk_format_to_pipe_format(state->conversion->format));
    const unsigned divisors[2] = {chroma_format <= PIPE_VIDEO_CHROMA_FORMAT_422 ? 2 : 1,
                                  chroma_format <= PIPE_VIDEO_CHROMA_FORMAT_420 ? 2 : 1};

    for (int c = 0; c < old_coords->num_components; c++) {
       comp[c] = nir_channel(b, old_coords, c);

       if (c < ARRAY_SIZE(divisors) && divisors[c] > 1) {
          if (state->unnormalized_coordinates)
             comp[c] = nir_fdiv(b, comp[c], nir_imm_float(b, divisors[c]));

          if (conversion->chroma_offsets[c] == VK_CHROMA_LOCATION_COSITED_EVEN) {
             if (state->unnormalized_coordinates) {
                comp[c] = implicit_downsampled_coord_unnormalized(b, comp[c], divisors[c]);
             } else {
                if (!image_size)
                   image_size = get_texture_size(state, state->tex_deref);

                comp[c] = implicit_downsampled_coord(b, comp[c], nir_channel(b, image_size, c), divisors[c]);
             }
          }
       }
    }

    return nir_vec(b, comp, old_coords->num_components);
 }

 static nir_ssa_def *
 create_plane_tex_instr_implicit(struct ycbcr_state *state, uint32_t plane)
 {
    nir_builder *b = state->builder;
    nir_tex_instr *old_tex = state->origin_tex;
    nir_tex_instr *tex = nir_tex_instr_create(b->shader, old_tex->num_srcs + 1);
    for (uint32_t i = 0; i < old_tex->num_srcs; i++) {
       tex->src[i].src_type = old_tex->src[i].src_type;

       switch (old_tex->src[i].src_type) {
       case nir_tex_src_coord:
          if (plane && true /*state->conversion->chroma_reconstruction*/) {
             assert(old_tex->src[i].src.is_ssa);
             tex->src[i].src =
                nir_src_for_ssa(implicit_downsampled_coords(state, old_tex->src[i].src.ssa));
             break;
          }
       FALLTHROUGH;
       default:
          nir_src_copy(&tex->src[i].src, &old_tex->src[i].src, &tex->instr);
          break;
       }
    }

    tex->src[tex->num_srcs - 1].src = nir_src_for_ssa(nir_imm_int(b, plane));
    tex->src[tex->num_srcs - 1].src_type = nir_tex_src_plane;

    tex->sampler_dim = old_tex->sampler_dim;
    tex->dest_type = old_tex->dest_type;
    tex->is_array = old_tex->is_array;

    tex->op = old_tex->op;
    tex->coord_components = old_tex->coord_components;
    tex->is_new_style_shadow = old_tex->is_new_style_shadow;
    tex->component = old_tex->component;

    tex->texture_index = old_tex->texture_index;
    tex->sampler_index = old_tex->sampler_index;

    nir_ssa_dest_init(&tex->instr, &tex->dest, old_tex->dest.ssa.num_components,
                      nir_dest_bit_size(old_tex->dest), NULL);
    nir_builder_instr_insert(b, &tex->instr);

    return &tex->dest.ssa;
 }

 struct swizzle_info {
    unsigned plane[4];
    unsigned swizzle[4];
 };

 static struct swizzle_info
 get_plane_swizzles(VkFormat format)
 {
    int planes = vk_format_get_plane_count(format);
    switch (planes) {
    case 3:
       return (struct swizzle_info){{2, 0, 1, 0}, {0, 0, 0, 3}};
    case 2:
       return (struct swizzle_info){{1, 0, 1, 0}, {1, 0, 0, 3}};
    case 1:
       return (struct swizzle_info){{0, 0, 0, 0}, {0, 1, 2, 3}};
    default:
       unreachable("unhandled plane count for ycbcr swizzling");
    }
 }

 static nir_ssa_def *
 build_swizzled_components(nir_builder *builder, VkFormat format, VkComponentMapping mapping,
                           nir_ssa_def **plane_values)
 {
    struct swizzle_info plane_swizzle = get_plane_swizzles(format);
    enum pipe_swizzle swizzles[4];
    nir_ssa_def *values[4];

    vk_format_compose_swizzles(&mapping, (const unsigned char[4]){0, 1, 2, 3}, swizzles);

    nir_ssa_def *zero = nir_imm_float(builder, 0.0f);
    nir_ssa_def *one = nir_imm_float(builder, 1.0f);

    for (unsigned i = 0; i < 4; ++i) {
       switch (swizzles[i]) {
       case PIPE_SWIZZLE_X:
       case PIPE_SWIZZLE_Y:
       case PIPE_SWIZZLE_Z:
       case PIPE_SWIZZLE_W: {
          unsigned channel = swizzles[i] - PIPE_SWIZZLE_X;
          values[i] = nir_channel(builder, plane_values[plane_swizzle.plane[channel]],
                                  plane_swizzle.swizzle[channel]);
          break;
       }
       case PIPE_SWIZZLE_0:
          values[i] = zero;
          break;
       case PIPE_SWIZZLE_1:
          values[i] = one;
          break;
       default:
          unreachable("unhandled swizzle");
       }
    }
    return nir_vec(builder, values, 4);
 }

 static bool
 try_lower_tex_ycbcr(const struct radv_pipeline_layout *layout, nir_builder *builder,
                     nir_tex_instr *tex)
 {
    int deref_src_idx = nir_tex_instr_src_index(tex, nir_tex_src_texture_deref);
    assert(deref_src_idx >= 0);
    nir_deref_instr *deref = nir_src_as_deref(tex->src[deref_src_idx].src);

    nir_variable *var = nir_deref_instr_get_variable(deref);
    const struct radv_descriptor_set_layout *set_layout =
       layout->set[var->data.descriptor_set].layout;
    const struct radv_descriptor_set_binding_layout *binding =
       &set_layout->binding[var->data.binding];
    const struct radv_sampler_ycbcr_conversion_state *ycbcr_samplers =
       radv_immutable_ycbcr_samplers(set_layout, var->data.binding);

    if (!ycbcr_samplers)
       return false;

    assert(binding->immutable_samplers_offset);
    const uint32_t *immutable_samplers =
       radv_immutable_samplers(set_layout, binding);

    /* For the following instructions, we don't apply any change and let the
     * instruction apply to the first plane.
     */
    if (tex->op == nir_texop_txs || tex->op == nir_texop_query_levels || tex->op == nir_texop_lod)
       return false;

    assert(tex->texture_index == 0);
    unsigned array_index = 0;
    if (deref->deref_type != nir_deref_type_var) {
       assert(deref->deref_type == nir_deref_type_array);
       if (!nir_src_is_const(deref->arr.index))
          return false;
       array_index = nir_src_as_uint(deref->arr.index);
       array_index = MIN2(array_index, binding->array_size - 1);
    }
    const struct radv_sampler_ycbcr_conversion_state *ycbcr_sampler = ycbcr_samplers + array_index;

    if (ycbcr_sampler->format == VK_FORMAT_UNDEFINED)
       return false;

    bool unnormalized_coordinates = immutable_samplers[4 * array_index + 0] & S_008F30_FORCE_UNNORMALIZED(1);

    struct ycbcr_state state = {
       .builder = builder,
       .origin_tex = tex,
       .tex_deref = deref,
       .conversion = ycbcr_sampler,
       .unnormalized_coordinates = unnormalized_coordinates,
    };

    builder->cursor = nir_before_instr(&tex->instr);

    VkFormat format = state.conversion->format;
    const int plane_count = vk_format_get_plane_count(format);
    nir_ssa_def *plane_values[3];

    for (int p = 0; p < plane_count; ++p) {
       plane_values[p] = create_plane_tex_instr_implicit(&state, p);
    }

    nir_ssa_def *result =
       build_swizzled_components(builder, format, ycbcr_sampler->components, plane_values);
    if (state.conversion->ycbcr_model != VK_SAMPLER_YCBCR_MODEL_CONVERSION_RGB_IDENTITY) {
       VkFormat first_format = vk_format_get_plane_format(format, 0);
       uint32_t bits =
          vk_format_get_component_bits(first_format, UTIL_FORMAT_COLORSPACE_RGB, PIPE_SWIZZLE_X);
       /* TODO: swizzle and bpcs */
       uint32_t bpcs[3] = {bits, bits, bits};
       result = nir_convert_ycbcr_to_rgb(builder, state.conversion->ycbcr_model,
                                         state.conversion->ycbcr_range, result, bpcs);
    }

    nir_ssa_def_rewrite_uses(&tex->dest.ssa, result);
    nir_instr_remove(&tex->instr);

    return true;
 }

 static bool
 radv_nir_lower_ycbcr_textures_instr(nir_builder *b, nir_instr *instr, void *layout)
 {
    if (instr->type != nir_instr_type_tex)
       return false;

    nir_tex_instr *tex = nir_instr_as_tex(instr);
    return try_lower_tex_ycbcr(layout, b, tex);
 }

 bool
 radv_nir_lower_ycbcr_textures(nir_shader *shader, const struct radv_pipeline_layout *layout)
 {
    return nir_shader_instructions_pass(shader,
                                        radv_nir_lower_ycbcr_textures_instr,
                                        nir_metadata_block_index |
                                        nir_metadata_dominance,
                                        (void *)layout);
 }
	/*
	* Copyright © 2017 Intel Corporation
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the "Software"),
	* to deal in the Software without restriction, including without limitation
	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	* and/or sell copies of the Software, and to permit persons to whom the
	* Software is furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice (including the next
	* paragraph) shall be included in all copies or substantial portions of the
	* Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
	* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
	* IN THE SOFTWARE.
	*/

	#include "nir/nir.h"
	#include "nir/nir_builder.h"
	#include "nir/nir_vulkan.h"
	#include "radv_private.h"
	#include "radv_shader.h"
	#include "vk_format.h"

	struct ycbcr_state {
	nir_builder *builder;
	nir_ssa_def *image_size;
	nir_tex_instr *origin_tex;
	nir_deref_instr *tex_deref;
	const struct radv_sampler_ycbcr_conversion_state *conversion;
	bool unnormalized_coordinates;
	};

	static nir_ssa_def *
	get_texture_size(struct ycbcr_state state, nir_deref_instr texture)
	{
	nir_builder *b = state->builder;
	const struct glsl_type *type = texture->type;
	nir_tex_instr *tex = nir_tex_instr_create(b->shader, 1);

	tex->op = nir_texop_txs;
	tex->sampler_dim = glsl_get_sampler_dim(type);
	tex->is_array = glsl_sampler_type_is_array(type);
	tex->is_shadow = glsl_sampler_type_is_shadow(type);
	tex->dest_type = nir_type_int32;

	tex->src[0].src_type = nir_tex_src_texture_deref;
	tex->src[0].src = nir_src_for_ssa(&texture->dest.ssa);

	nir_ssa_dest_init(&tex->instr, &tex->dest, nir_tex_instr_dest_size(tex), 32, NULL);
	nir_builder_instr_insert(b, &tex->instr);

	state->builder->shader->info.uses_resource_info_query = true;

	return nir_i2f32(b, &tex->dest.ssa);
	}

	static nir_ssa_def *
	implicit_downsampled_coord(nir_builder b, nir_ssa_def value, nir_ssa_def *max_value,
	int div_scale)
	{
	return nir_fadd(
	b, value,
	nir_fdiv(b, nir_imm_float(b, 1.0f), nir_fmul(b, nir_imm_float(b, div_scale), max_value)));
	}

	static nir_ssa_def *
	implicit_downsampled_coord_unnormalized(nir_builder b, nir_ssa_def value, int div_scale)
	{
	return nir_fadd(
	b, value,
	nir_imm_float(b, 1.0f / (float)div_scale));
	}

	static nir_ssa_def *
	implicit_downsampled_coords(struct ycbcr_state state, nir_ssa_def old_coords)
	{
	nir_builder *b = state->builder;
	const struct radv_sampler_ycbcr_conversion_state *conversion = state->conversion;
	nir_ssa_def *image_size = NULL;
	nir_ssa_def *comp[4] = {
	NULL,
	};
	enum pipe_video_chroma_format chroma_format =
	pipe_format_to_chroma_format(vk_format_to_pipe_format(state->conversion->format));
	const unsigned divisors[2] = {chroma_format <= PIPE_VIDEO_CHROMA_FORMAT_422 ? 2 : 1,
	chroma_format <= PIPE_VIDEO_CHROMA_FORMAT_420 ? 2 : 1};

	for (int c = 0; c < old_coords->num_components; c++) {
	comp[c] = nir_channel(b, old_coords, c);

	if (c < ARRAY_SIZE(divisors) && divisors[c] > 1) {
	if (state->unnormalized_coordinates)
	comp[c] = nir_fdiv(b, comp[c], nir_imm_float(b, divisors[c]));

	if (conversion->chroma_offsets[c] == VK_CHROMA_LOCATION_COSITED_EVEN) {
	if (state->unnormalized_coordinates) {
	comp[c] = implicit_downsampled_coord_unnormalized(b, comp[c], divisors[c]);
	} else {
	if (!image_size)
	image_size = get_texture_size(state, state->tex_deref);

	comp[c] = implicit_downsampled_coord(b, comp[c], nir_channel(b, image_size, c), divisors[c]);
	}
	}
	}
	}

	return nir_vec(b, comp, old_coords->num_components);
	}

	static nir_ssa_def *
	create_plane_tex_instr_implicit(struct ycbcr_state *state, uint32_t plane)
	{
	nir_builder *b = state->builder;
	nir_tex_instr *old_tex = state->origin_tex;
	nir_tex_instr *tex = nir_tex_instr_create(b->shader, old_tex->num_srcs + 1);
	for (uint32_t i = 0; i < old_tex->num_srcs; i++) {
	tex->src[i].src_type = old_tex->src[i].src_type;

	switch (old_tex->src[i].src_type) {
	case nir_tex_src_coord:
	if (plane && true /state->conversion->chroma_reconstruction/) {
	assert(old_tex->src[i].src.is_ssa);
	tex->src[i].src =
	nir_src_for_ssa(implicit_downsampled_coords(state, old_tex->src[i].src.ssa));
	break;
	}
	FALLTHROUGH;
	default:
	nir_src_copy(&tex->src[i].src, &old_tex->src[i].src, &tex->instr);
	break;
	}
	}

	tex->src[tex->num_srcs - 1].src = nir_src_for_ssa(nir_imm_int(b, plane));
	tex->src[tex->num_srcs - 1].src_type = nir_tex_src_plane;

	tex->sampler_dim = old_tex->sampler_dim;
	tex->dest_type = old_tex->dest_type;
	tex->is_array = old_tex->is_array;

	tex->op = old_tex->op;
	tex->coord_components = old_tex->coord_components;
	tex->is_new_style_shadow = old_tex->is_new_style_shadow;
	tex->component = old_tex->component;

	tex->texture_index = old_tex->texture_index;
	tex->sampler_index = old_tex->sampler_index;

	nir_ssa_dest_init(&tex->instr, &tex->dest, old_tex->dest.ssa.num_components,
	nir_dest_bit_size(old_tex->dest), NULL);
	nir_builder_instr_insert(b, &tex->instr);

	return &tex->dest.ssa;
	}

	struct swizzle_info {
	unsigned plane[4];
	unsigned swizzle[4];
	};

	static struct swizzle_info
	get_plane_swizzles(VkFormat format)
	{
	int planes = vk_format_get_plane_count(format);
	switch (planes) {
	case 3:
	return (struct swizzle_info){{2, 0, 1, 0}, {0, 0, 0, 3}};
	case 2:
	return (struct swizzle_info){{1, 0, 1, 0}, {1, 0, 0, 3}};
	case 1:
	return (struct swizzle_info){{0, 0, 0, 0}, {0, 1, 2, 3}};
	default:
	unreachable("unhandled plane count for ycbcr swizzling");
	}
	}

	static nir_ssa_def *
	build_swizzled_components(nir_builder *builder, VkFormat format, VkComponentMapping mapping,
	nir_ssa_def **plane_values)
	{
	struct swizzle_info plane_swizzle = get_plane_swizzles(format);
	enum pipe_swizzle swizzles[4];
	nir_ssa_def *values[4];

	vk_format_compose_swizzles(&mapping, (const unsigned char[4]){0, 1, 2, 3}, swizzles);

	nir_ssa_def *zero = nir_imm_float(builder, 0.0f);
	nir_ssa_def *one = nir_imm_float(builder, 1.0f);

	for (unsigned i = 0; i < 4; ++i) {
	switch (swizzles[i]) {
	case PIPE_SWIZZLE_X:
	case PIPE_SWIZZLE_Y:
	case PIPE_SWIZZLE_Z:
	case PIPE_SWIZZLE_W: {
	unsigned channel = swizzles[i] - PIPE_SWIZZLE_X;
	values[i] = nir_channel(builder, plane_values[plane_swizzle.plane[channel]],
	plane_swizzle.swizzle[channel]);
	break;
	}
	case PIPE_SWIZZLE_0:
	values[i] = zero;
	break;
	case PIPE_SWIZZLE_1:
	values[i] = one;
	break;
	default:
	unreachable("unhandled swizzle");
	}
	}
	return nir_vec(builder, values, 4);
	}

	static bool
	try_lower_tex_ycbcr(const struct radv_pipeline_layout layout, nir_builder builder,
	nir_tex_instr *tex)
	{
	int deref_src_idx = nir_tex_instr_src_index(tex, nir_tex_src_texture_deref);
	assert(deref_src_idx >= 0);
	nir_deref_instr *deref = nir_src_as_deref(tex->src[deref_src_idx].src);

	nir_variable *var = nir_deref_instr_get_variable(deref);
	const struct radv_descriptor_set_layout *set_layout =
	layout->set[var->data.descriptor_set].layout;
	const struct radv_descriptor_set_binding_layout *binding =
	&set_layout->binding[var->data.binding];
	const struct radv_sampler_ycbcr_conversion_state *ycbcr_samplers =
	radv_immutable_ycbcr_samplers(set_layout, var->data.binding);

	if (!ycbcr_samplers)
	return false;

	assert(binding->immutable_samplers_offset);
	const uint32_t *immutable_samplers =
	radv_immutable_samplers(set_layout, binding);

	/* For the following instructions, we don't apply any change and let the
	* instruction apply to the first plane.
	*/
	if (tex->op == nir_texop_txs \|\| tex->op == nir_texop_query_levels \|\| tex->op == nir_texop_lod)
	return false;

	assert(tex->texture_index == 0);
	unsigned array_index = 0;
	if (deref->deref_type != nir_deref_type_var) {
	assert(deref->deref_type == nir_deref_type_array);
	if (!nir_src_is_const(deref->arr.index))
	return false;
	array_index = nir_src_as_uint(deref->arr.index);
	array_index = MIN2(array_index, binding->array_size - 1);
	}
	const struct radv_sampler_ycbcr_conversion_state *ycbcr_sampler = ycbcr_samplers + array_index;

	if (ycbcr_sampler->format == VK_FORMAT_UNDEFINED)
	return false;

	bool unnormalized_coordinates = immutable_samplers[4 * array_index + 0] & S_008F30_FORCE_UNNORMALIZED(1);

	struct ycbcr_state state = {
	.builder = builder,
	.origin_tex = tex,
	.tex_deref = deref,
	.conversion = ycbcr_sampler,
	.unnormalized_coordinates = unnormalized_coordinates,
	};

	builder->cursor = nir_before_instr(&tex->instr);

	VkFormat format = state.conversion->format;
	const int plane_count = vk_format_get_plane_count(format);
	nir_ssa_def *plane_values[3];

	for (int p = 0; p < plane_count; ++p) {
	plane_values[p] = create_plane_tex_instr_implicit(&state, p);
	}

	nir_ssa_def *result =
	build_swizzled_components(builder, format, ycbcr_sampler->components, plane_values);
	if (state.conversion->ycbcr_model != VK_SAMPLER_YCBCR_MODEL_CONVERSION_RGB_IDENTITY) {
	VkFormat first_format = vk_format_get_plane_format(format, 0);
	uint32_t bits =
	vk_format_get_component_bits(first_format, UTIL_FORMAT_COLORSPACE_RGB, PIPE_SWIZZLE_X);
	/* TODO: swizzle and bpcs */
	uint32_t bpcs[3] = {bits, bits, bits};
	result = nir_convert_ycbcr_to_rgb(builder, state.conversion->ycbcr_model,
	state.conversion->ycbcr_range, result, bpcs);
	}

	nir_ssa_def_rewrite_uses(&tex->dest.ssa, result);
	nir_instr_remove(&tex->instr);

	return true;
	}

	static bool
	radv_nir_lower_ycbcr_textures_instr(nir_builder b, nir_instr instr, void *layout)
	{
	if (instr->type != nir_instr_type_tex)
	return false;

	nir_tex_instr *tex = nir_instr_as_tex(instr);
	return try_lower_tex_ycbcr(layout, b, tex);
	}

	bool
	radv_nir_lower_ycbcr_textures(nir_shader shader, const struct radv_pipeline_layout layout)
	{
	return nir_shader_instructions_pass(shader,
	radv_nir_lower_ycbcr_textures_instr,
	nir_metadata_block_index \|
	nir_metadata_dominance,
	(void *)layout);
	}