nir_texop_txl, /**< Texture look-up with explicit LOD */
nir_texop_txd, /**< Texture look-up with partial derivatives */
nir_texop_txf, /**< Texel fetch with explicit LOD */
- nir_texop_txf_ms, /**< Multisample texture fetch */
+ nir_texop_txf_ms, /**< Multisample texture fetch */
+ nir_texop_txf_ms_fb, /**< Multisample texture fetch from framebuffer */
nir_texop_txf_ms_mcs, /**< Multisample compression value fetch */
nir_texop_txs, /**< Texture size */
nir_texop_lod, /**< Texture lod query */
case nir_texop_txd:
case nir_texop_txf:
case nir_texop_txf_ms:
+ case nir_texop_txf_ms_fb:
case nir_texop_tg4:
return false;
default:
switch (instr->op) {
case nir_texop_txf:
case nir_texop_txf_ms:
+ case nir_texop_txf_ms_fb:
case nir_texop_txf_ms_mcs:
case nir_texop_samples_identical:
return nir_type_int;
const nir_lower_wpos_ytransform_options *options);
bool nir_lower_wpos_center(nir_shader *shader, const bool for_sample_shading);
+bool nir_lower_fb_read(nir_shader *shader);
+
typedef struct nir_lower_drawpixels_options {
gl_state_index16 texcoord_state_tokens[STATE_LENGTH];
gl_state_index16 scale_state_tokens[STATE_LENGTH];
--- /dev/null
+/*
+ * Copyright © 2019 Google, Inc.
+ *
+ * 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.h"
+#include "nir_builder.h"
+
+/* Lowing for fragment shader load_output.
+ *
+ * This pass supports the blend_equation_advanced, where a fragment
+ * shader loads the output (fragcolor) to read the current framebuffer.
+ * It does this by lowering the output read to a txf_ms_fb instruction.
+ * This instruction works similarly to a normal txf_ms except without
+ * taking a texture source argument. (The driver backend is expected
+ * to wire this up to a free texture slot which is configured to read
+ * from the framebuffer.)
+ *
+ * This should be run after lower_wpos_ytransform, because the tex
+ * coordinates should be the physical fragcoord, not the logical
+ * y-flipped coord.
+ *
+ * Note that this pass explicitly does *not* add a sampler uniform
+ * (as txf_ms_fb does not reference a texture). The driver backend
+ * is going to want nif->info.num_textures to include the count of
+ * number of textures *not* including the one it inserts to sample
+ * from the framebuffer, so it more easily knows where to insert the
+ * hidden texture to read from the fb.
+ */
+
+static void
+lower_fb_read(nir_builder *b, nir_intrinsic_instr *intr)
+{
+ b->cursor = nir_before_instr(&intr->instr);
+
+ nir_ssa_def *fragcoord = nir_load_frag_coord(b);
+ nir_ssa_def *sampid = nir_load_sample_id(b);
+
+ fragcoord = nir_f2i32(b, fragcoord);
+
+ nir_tex_instr *tex = nir_tex_instr_create(b->shader, 2);
+ tex->op = nir_texop_txf_ms_fb;
+ tex->sampler_dim = GLSL_SAMPLER_DIM_2D;
+ tex->coord_components = 2;
+ tex->dest_type = nir_type_float;
+ tex->src[0].src_type = nir_tex_src_coord;
+ tex->src[0].src = nir_src_for_ssa(nir_channels(b, fragcoord, 0x3));
+ tex->src[1].src_type = nir_tex_src_ms_index;
+ tex->src[1].src = nir_src_for_ssa(sampid);
+
+ nir_ssa_dest_init(&tex->instr, &tex->dest, 4, 32, NULL);
+ nir_builder_instr_insert(b, &tex->instr);
+
+ nir_ssa_def_rewrite_uses(&intr->dest.ssa, nir_src_for_ssa(&tex->dest.ssa));
+}
+
+bool
+nir_lower_fb_read(nir_shader *shader)
+{
+ bool progress = false;
+
+ assert(shader->info.stage == MESA_SHADER_FRAGMENT);
+
+ nir_foreach_function(function, shader) {
+ nir_function_impl *impl = function->impl;
+
+ if (!impl)
+ continue;
+
+ nir_foreach_block(block, impl) {
+ nir_foreach_instr_safe(instr, block) {
+ if (instr->type != nir_instr_type_intrinsic)
+ continue;
+
+ nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
+ if (intr->intrinsic != nir_intrinsic_load_output)
+ continue;
+
+ /* TODO KHR_blend_equation_advanced is limited to non-MRT
+ * scenarios.. but possible there are other extensions
+ * where this pass would be useful that do support MRT?
+ *
+ * I guess for now I'll leave that as an exercise for the
+ * reader.
+ */
+ if (nir_intrinsic_base(intr) != 0 ||
+ nir_src_as_uint(intr->src[0]) != 0)
+ continue;
+
+ nir_builder b;
+ nir_builder_init(&b, impl);
+ lower_fb_read(&b, intr);
+ progress = true;
+ }
+ }
+
+ nir_metadata_preserve(impl, nir_metadata_block_index |
+ nir_metadata_dominance);
+
+ }
+
+ return progress;
+}
case nir_texop_txf_ms:
fprintf(fp, "txf_ms ");
break;
+ case nir_texop_txf_ms_fb:
+ fprintf(fp, "txf_ms_fb ");
+ break;
case nir_texop_txf_ms_mcs:
fprintf(fp, "txf_ms_mcs ");
break;
fprintf(fp, " } (offsets)");
}
- if (!has_texture_deref) {
- fprintf(fp, ", %u (texture)", instr->texture_index);
- }
+ if (instr->op != nir_texop_txf_ms_fb) {
+ if (!has_texture_deref) {
+ fprintf(fp, ", %u (texture)", instr->texture_index);
+ }
- if (!has_sampler_deref) {
- fprintf(fp, ", %u (sampler)", instr->sampler_index);
+ if (!has_sampler_deref) {
+ fprintf(fp, ", %u (sampler)", instr->sampler_index);
+ }
}
}
projects / mesa.git / commitdiff