radv: switch to nir_intrinsic_load_input_attachment_coord

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/35556>

src/amd/vulkan/nir/radv_nir.h

@@ -48,6 +48,8 @@ bool radv_nir_lower_primitive_shading_rate(nir_shader *nir, enum amd_gfx_level g
 bool radv_nir_lower_fs_intrinsics(nir_shader *nir, const struct radv_shader_stage *fs_stage,
                                   const struct radv_graphics_state_key *gfx_state);
 
+bool radv_nir_lower_fs_input_attachment(nir_shader *nir);
+
 bool radv_nir_lower_fs_barycentric(nir_shader *shader, const struct radv_graphics_state_key *gfx_state,
                                    unsigned rast_prim);
 

src/amd/vulkan/nir/radv_nir_lower_fs_intrinsics.c

@@ -125,3 +125,31 @@ radv_nir_lower_fs_intrinsics(nir_shader *nir, const struct radv_shader_stage *fs
    struct ctx ctx = { .fs_stage = fs_stage, .gfx_state = gfx_state };
    return nir_shader_intrinsics_pass(nir, pass, nir_metadata_none, &ctx);
 }
+
+static bool
+lower_load_input_attachment(nir_builder *b, nir_intrinsic_instr *intrin, void *state)
+{
+   switch (intrin->intrinsic) {
+   case nir_intrinsic_load_input_attachment_coord: {
+      b->cursor = nir_before_instr(&intrin->instr);
+
+      nir_def *pos = nir_f2i32(b, nir_load_frag_coord(b));
+      nir_def *layer = nir_load_layer_id(b);
+      nir_def *coord = nir_vec3(b, nir_channel(b, pos, 0), nir_channel(b, pos, 1), layer);
+
+      nir_def_replace(&intrin->def, coord);
+      return true;
+   }
+   default:
+      return false;
+   }
+}
+
+bool
+radv_nir_lower_fs_input_attachment(nir_shader *nir)
+{
+   if (!nir->info.fs.uses_fbfetch_output)
+      return false;
+
+   return nir_shader_intrinsics_pass(nir, lower_load_input_attachment, nir_metadata_control_flow, NULL);
+}

src/amd/vulkan/radv_pipeline_graphics.c

@@ -2763,6 +2763,8 @@ radv_graphics_shaders_compile(struct radv_device *device, struct vk_pipeline_cac
       if (!gfx_state->ps.has_epilog)
          radv_nir_remap_color_attachment(stages[MESA_SHADER_FRAGMENT].nir, gfx_state);
 
+      NIR_PASS(update_info, stages[MESA_SHADER_FRAGMENT].nir, radv_nir_lower_fs_input_attachment);
+
       NIR_PASS(update_info, stages[MESA_SHADER_FRAGMENT].nir, nir_opt_frag_coord_to_pixel_coord);
       if (update_info)
          nir_shader_gather_info(stages[MESA_SHADER_FRAGMENT].nir,

src/amd/vulkan/radv_shader.c

@@ -454,8 +454,7 @@ radv_shader_spirv_to_nir(struct radv_device *device, const struct radv_shader_st
       if (nir->info.stage == MESA_SHADER_FRAGMENT)
          NIR_PASS(_, nir, nir_lower_input_attachments,
                   &(nir_input_attachment_options){
-                     .use_fragcoord_sysval = true,
-                     .use_layer_id_sysval = true,
+                     .use_ia_coord_intrin = true,
                   });
 
       nir_remove_dead_variables_options dead_vars_opts = {