/* * Copyright © 2023 Intel Corporation * SPDX-License-Identifier: MIT */ #include "intel_nir.h" #include "compiler/nir/nir_builder.h" /* * This pass lowers a few of the sparse instructions to something HW can * handle. * * The image_*_sparse_load intrinsics are lowered into 2 instructions, a * regular image_*_load intrinsic and a sparse texture txf operation and * reconstructs the sparse vector of the original intrinsic using the 2 new * values. We need to do this because our backend implements image load/store * using the dataport and the dataport unit doesn't provide residency * information. We need to use the sampler for residency. * * The is_sparse_texels_resident intrinsic is lowered to a bit checking * operation as the data reported by the sampler is a single bit per lane in * the first component. * * The tex_* instructions with a compare value need to be lower into 2 * instructions due to a HW limitation : * * SKL PRMs, Volume 7: 3D-Media-GPGPU, Messages, SIMD Payloads : * * "The Pixel Null Mask field, when enabled via the Pixel Null Mask Enable * will be incorect for sample_c when applied to a surface with 64-bit per * texel format such as R16G16BA16_UNORM. Pixel Null mask Enable may * incorrectly report pixels as referencing a Null surface." */ static void lower_is_sparse_texels_resident(nir_builder *b, nir_intrinsic_instr *intrin) { b->cursor = nir_instr_remove(&intrin->instr); nir_def_rewrite_uses( &intrin->def, nir_i2b(b, nir_iand(b, intrin->src[0].ssa, nir_ishl(b, nir_imm_int(b, 1), nir_load_subgroup_invocation(b))))); } static void lower_sparse_residency_code_and(nir_builder *b, nir_intrinsic_instr *intrin) { b->cursor = nir_instr_remove(&intrin->instr); nir_def_rewrite_uses( &intrin->def, nir_iand(b, intrin->src[0].ssa, intrin->src[1].ssa)); } static void lower_sparse_image_load(nir_builder *b, nir_intrinsic_instr *intrin) { b->cursor = nir_instr_remove(&intrin->instr); const bool bindless = intrin->intrinsic == nir_intrinsic_bindless_image_sparse_load; const bool array = nir_intrinsic_image_array(intrin); const enum glsl_sampler_dim dim = nir_intrinsic_image_dim(intrin); const unsigned fmt = nir_intrinsic_format(intrin); const enum gl_access_qualifier access = nir_intrinsic_access(intrin); const nir_alu_type dest_type = nir_intrinsic_dest_type(intrin); nir_src *s = intrin->src; nir_def *img_load = bindless ? nir_bindless_image_load(b, intrin->num_components - 1, intrin->def.bit_size, s[0].ssa, s[1].ssa, s[2].ssa, s[3].ssa, .image_dim = dim, .image_array = array, .format = fmt, .access = access, .dest_type = dest_type) : nir_image_load(b, intrin->num_components - 1, intrin->def.bit_size, s[0].ssa, s[1].ssa, s[2].ssa, s[3].ssa, .image_dim = dim, .image_array = array, .format = fmt, .access = access, .dest_type = dest_type); nir_def *dests[NIR_MAX_VEC_COMPONENTS]; for (unsigned i = 0; i < intrin->num_components - 1; i++) { dests[i] = nir_channel(b, img_load, i); } /* Use texture instruction to compute residency */ nir_def *coord; if (nir_intrinsic_image_dim(intrin) == GLSL_SAMPLER_DIM_CUBE && array) { nir_def *img_layer = nir_channel(b, intrin->src[1].ssa, 2); nir_def *tex_slice = nir_idiv(b, img_layer, nir_imm_int(b, 6)); nir_def *tex_face = nir_iadd(b, img_layer, nir_ineg(b, nir_imul_imm(b, tex_slice, 6))); nir_def *comps[4] = { nir_channel(b, intrin->src[1].ssa, 0), nir_channel(b, intrin->src[1].ssa, 1), tex_face, tex_slice }; coord = nir_vec(b, comps, 4); } else { const unsigned comps = nir_image_intrinsic_coord_components(intrin); coord = nir_channels(b, intrin->src[1].ssa, nir_component_mask(comps)); } nir_def *txf = nir_txf(b, coord, .texture_offset = bindless ? NULL : intrin->src[0].ssa, .texture_handle = bindless ? intrin->src[0].ssa : NULL, .dim = nir_intrinsic_image_dim(intrin), .dest_type = nir_type_float32, /* dest is unused */ .is_array = array, .is_sparse = true); dests[intrin->num_components - 1] = nir_channel(b, txf, 4); nir_def_rewrite_uses( &intrin->def, nir_vec(b, dests, intrin->num_components)); } static void split_tex_residency(nir_builder *b, nir_tex_instr *tex, int compare_idx) { b->cursor = nir_after_instr(&tex->instr); /* Clone the original instruction */ nir_tex_instr *sparse_tex = nir_instr_as_tex(nir_instr_clone(b->shader, &tex->instr)); nir_def_init(&sparse_tex->instr, &sparse_tex->def, tex->def.num_components, tex->def.bit_size); nir_builder_instr_insert(b, &sparse_tex->instr); /* Drop the compare source on the cloned instruction */ if (compare_idx != -1) nir_tex_instr_remove_src(sparse_tex, compare_idx); /* Drop the residency query on the original tex instruction */ tex->is_sparse = false; tex->def.num_components = tex->def.num_components - 1; nir_def *new_comps[NIR_MAX_VEC_COMPONENTS]; for (unsigned i = 0; i < tex->def.num_components; i++) new_comps[i] = nir_channel(b, &tex->def, i); new_comps[tex->def.num_components] = nir_channel(b, &sparse_tex->def, tex->def.num_components); nir_def *new_vec = nir_vec(b, new_comps, sparse_tex->def.num_components); nir_def_rewrite_uses_after(&tex->def, new_vec); } static bool lower_sparse_intrinsics(nir_builder *b, nir_instr *instr, void *cb_data) { switch (instr->type) { case nir_instr_type_intrinsic: { nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); switch (intrin->intrinsic) { case nir_intrinsic_image_sparse_load: case nir_intrinsic_bindless_image_sparse_load: lower_sparse_image_load(b, intrin); return true; case nir_intrinsic_is_sparse_texels_resident: lower_is_sparse_texels_resident(b, intrin); return true; case nir_intrinsic_sparse_residency_code_and: lower_sparse_residency_code_and(b, intrin); return true; default: return false; } } case nir_instr_type_tex: { nir_tex_instr *tex = nir_instr_as_tex(instr); int comp_idx = nir_tex_instr_src_index(tex, nir_tex_src_comparator); if (comp_idx != -1 && tex->is_sparse) { split_tex_residency(b, tex, comp_idx); return true; } return false; } default: return false; } } bool intel_nir_lower_sparse_intrinsics(nir_shader *nir) { return nir_shader_instructions_pass(nir, lower_sparse_intrinsics, nir_metadata_control_flow, NULL); }