| /* |
| * Copyright © 2019 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.h" |
| #include "nir_builder.h" |
| |
| static nir_ssa_def * |
| read_first_invocation(nir_builder *b, nir_ssa_def *x) |
| { |
| nir_intrinsic_instr *first = |
| nir_intrinsic_instr_create(b->shader, |
| nir_intrinsic_read_first_invocation); |
| first->num_components = x->num_components; |
| first->src[0] = nir_src_for_ssa(x); |
| nir_ssa_dest_init(&first->instr, &first->dest, |
| x->num_components, x->bit_size, NULL); |
| nir_builder_instr_insert(b, &first->instr); |
| return &first->dest.ssa; |
| } |
| |
| static bool |
| lower_non_uniform_tex_access(nir_builder *b, nir_tex_instr *tex) |
| { |
| if (!tex->texture_non_uniform && !tex->sampler_non_uniform) |
| return false; |
| |
| /* We can have at most one texture and one sampler handle */ |
| nir_ssa_def *handles[2]; |
| nir_deref_instr *parent_derefs[2]; |
| int texture_deref_handle = -1; |
| int sampler_deref_handle = -1; |
| unsigned handle_count = 0; |
| for (unsigned i = 0; i < tex->num_srcs; i++) { |
| switch (tex->src[i].src_type) { |
| case nir_tex_src_texture_offset: |
| case nir_tex_src_texture_handle: |
| case nir_tex_src_texture_deref: |
| if (!tex->texture_non_uniform) |
| continue; |
| break; |
| |
| case nir_tex_src_sampler_offset: |
| case nir_tex_src_sampler_handle: |
| case nir_tex_src_sampler_deref: |
| if (!tex->sampler_non_uniform) |
| continue; |
| break; |
| |
| default: |
| continue; |
| } |
| |
| assert(handle_count < 2); |
| assert(tex->src[i].src.is_ssa); |
| nir_ssa_def *handle = tex->src[i].src.ssa; |
| if (handle->parent_instr->type == nir_instr_type_deref) { |
| nir_deref_instr *deref = nir_instr_as_deref(handle->parent_instr); |
| nir_deref_instr *parent = nir_deref_instr_parent(deref); |
| if (deref->deref_type == nir_deref_type_var) |
| continue; |
| |
| assert(parent->deref_type == nir_deref_type_var); |
| assert(deref->deref_type == nir_deref_type_array); |
| |
| /* If it's constant, it's automatically uniform; don't bother. */ |
| if (nir_src_is_const(deref->arr.index)) |
| continue; |
| |
| handle = deref->arr.index.ssa; |
| |
| parent_derefs[handle_count] = parent; |
| if (tex->src[i].src_type == nir_tex_src_texture_deref) |
| texture_deref_handle = handle_count; |
| else |
| sampler_deref_handle = handle_count; |
| } |
| assert(handle->num_components == 1); |
| |
| handles[handle_count++] = handle; |
| } |
| |
| if (handle_count == 0) |
| return false; |
| |
| b->cursor = nir_instr_remove(&tex->instr); |
| |
| nir_push_loop(b); |
| |
| nir_ssa_def *all_equal_first = nir_imm_true(b); |
| nir_ssa_def *first[2]; |
| for (unsigned i = 0; i < handle_count; i++) { |
| first[i] = read_first_invocation(b, handles[i]); |
| nir_ssa_def *equal_first = nir_ieq(b, first[i], handles[i]); |
| all_equal_first = nir_iand(b, all_equal_first, equal_first); |
| } |
| |
| nir_push_if(b, all_equal_first); |
| |
| /* Replicate the derefs. */ |
| if (texture_deref_handle >= 0) { |
| int src_idx = nir_tex_instr_src_index(tex, nir_tex_src_texture_deref); |
| nir_deref_instr *deref = parent_derefs[texture_deref_handle]; |
| deref = nir_build_deref_array(b, deref, first[texture_deref_handle]); |
| tex->src[src_idx].src = nir_src_for_ssa(&deref->dest.ssa); |
| } |
| |
| if (sampler_deref_handle >= 0) { |
| int src_idx = nir_tex_instr_src_index(tex, nir_tex_src_sampler_deref); |
| nir_deref_instr *deref = parent_derefs[sampler_deref_handle]; |
| deref = nir_build_deref_array(b, deref, first[sampler_deref_handle]); |
| tex->src[src_idx].src = nir_src_for_ssa(&deref->dest.ssa); |
| } |
| |
| nir_builder_instr_insert(b, &tex->instr); |
| nir_jump(b, nir_jump_break); |
| |
| return true; |
| } |
| |
| static bool |
| lower_non_uniform_access_intrin(nir_builder *b, nir_intrinsic_instr *intrin, |
| unsigned handle_src) |
| { |
| if (!(nir_intrinsic_access(intrin) & ACCESS_NON_UNIFORM)) |
| return false; |
| |
| assert(intrin->src[handle_src].is_ssa); |
| nir_ssa_def *handle = intrin->src[handle_src].ssa; |
| nir_deref_instr *parent_deref = NULL; |
| if (handle->parent_instr->type == nir_instr_type_deref) { |
| nir_deref_instr *deref = nir_instr_as_deref(handle->parent_instr); |
| parent_deref = nir_deref_instr_parent(deref); |
| if (deref->deref_type == nir_deref_type_var) |
| return false; |
| |
| assert(parent_deref->deref_type == nir_deref_type_var); |
| assert(deref->deref_type == nir_deref_type_array); |
| |
| handle = deref->arr.index.ssa; |
| } |
| |
| /* If it's constant, it's automatically uniform; don't bother. */ |
| if (handle->parent_instr->type == nir_instr_type_load_const) |
| return false; |
| |
| b->cursor = nir_instr_remove(&intrin->instr); |
| |
| nir_push_loop(b); |
| |
| assert(handle->num_components == 1); |
| |
| nir_ssa_def *first = read_first_invocation(b, handle); |
| nir_push_if(b, nir_ieq(b, first, handle)); |
| |
| /* Replicate the deref. */ |
| if (parent_deref) { |
| nir_deref_instr *deref = nir_build_deref_array(b, parent_deref, first); |
| intrin->src[handle_src] = nir_src_for_ssa(&deref->dest.ssa); |
| } |
| |
| nir_builder_instr_insert(b, &intrin->instr); |
| nir_jump(b, nir_jump_break); |
| |
| return true; |
| } |
| |
| static bool |
| nir_lower_non_uniform_access_impl(nir_function_impl *impl, |
| enum nir_lower_non_uniform_access_type types) |
| { |
| bool progress = false; |
| |
| nir_builder b; |
| nir_builder_init(&b, impl); |
| |
| nir_foreach_block_safe(block, impl) { |
| nir_foreach_instr_safe(instr, block) { |
| switch (instr->type) { |
| case nir_instr_type_tex: { |
| nir_tex_instr *tex = nir_instr_as_tex(instr); |
| if ((types & nir_lower_non_uniform_texture_access) && |
| lower_non_uniform_tex_access(&b, tex)) |
| progress = true; |
| break; |
| } |
| |
| case nir_instr_type_intrinsic: { |
| nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); |
| switch (intrin->intrinsic) { |
| case nir_intrinsic_load_ubo: |
| if ((types & nir_lower_non_uniform_ubo_access) && |
| lower_non_uniform_access_intrin(&b, intrin, 0)) |
| progress = true; |
| break; |
| |
| case nir_intrinsic_load_ssbo: |
| case nir_intrinsic_ssbo_atomic_add: |
| case nir_intrinsic_ssbo_atomic_imin: |
| case nir_intrinsic_ssbo_atomic_umin: |
| case nir_intrinsic_ssbo_atomic_imax: |
| case nir_intrinsic_ssbo_atomic_umax: |
| case nir_intrinsic_ssbo_atomic_and: |
| case nir_intrinsic_ssbo_atomic_or: |
| case nir_intrinsic_ssbo_atomic_xor: |
| case nir_intrinsic_ssbo_atomic_exchange: |
| case nir_intrinsic_ssbo_atomic_comp_swap: |
| case nir_intrinsic_ssbo_atomic_fadd: |
| case nir_intrinsic_ssbo_atomic_fmin: |
| case nir_intrinsic_ssbo_atomic_fmax: |
| case nir_intrinsic_ssbo_atomic_fcomp_swap: |
| if ((types & nir_lower_non_uniform_ssbo_access) && |
| lower_non_uniform_access_intrin(&b, intrin, 0)) |
| progress = true; |
| break; |
| |
| case nir_intrinsic_store_ssbo: |
| /* SSBO Stores put the index in the second source */ |
| if ((types & nir_lower_non_uniform_ssbo_access) && |
| lower_non_uniform_access_intrin(&b, intrin, 1)) |
| progress = true; |
| break; |
| |
| case nir_intrinsic_image_load: |
| case nir_intrinsic_image_store: |
| case nir_intrinsic_image_atomic_add: |
| case nir_intrinsic_image_atomic_imin: |
| case nir_intrinsic_image_atomic_umin: |
| case nir_intrinsic_image_atomic_imax: |
| case nir_intrinsic_image_atomic_umax: |
| case nir_intrinsic_image_atomic_and: |
| case nir_intrinsic_image_atomic_or: |
| case nir_intrinsic_image_atomic_xor: |
| case nir_intrinsic_image_atomic_exchange: |
| case nir_intrinsic_image_atomic_comp_swap: |
| case nir_intrinsic_image_atomic_fadd: |
| case nir_intrinsic_image_size: |
| case nir_intrinsic_image_samples: |
| case nir_intrinsic_bindless_image_load: |
| case nir_intrinsic_bindless_image_store: |
| case nir_intrinsic_bindless_image_atomic_add: |
| case nir_intrinsic_bindless_image_atomic_imin: |
| case nir_intrinsic_bindless_image_atomic_umin: |
| case nir_intrinsic_bindless_image_atomic_imax: |
| case nir_intrinsic_bindless_image_atomic_umax: |
| case nir_intrinsic_bindless_image_atomic_and: |
| case nir_intrinsic_bindless_image_atomic_or: |
| case nir_intrinsic_bindless_image_atomic_xor: |
| case nir_intrinsic_bindless_image_atomic_exchange: |
| case nir_intrinsic_bindless_image_atomic_comp_swap: |
| case nir_intrinsic_bindless_image_atomic_fadd: |
| case nir_intrinsic_bindless_image_size: |
| case nir_intrinsic_bindless_image_samples: |
| case nir_intrinsic_image_deref_load: |
| case nir_intrinsic_image_deref_store: |
| case nir_intrinsic_image_deref_atomic_add: |
| case nir_intrinsic_image_deref_atomic_umin: |
| case nir_intrinsic_image_deref_atomic_imin: |
| case nir_intrinsic_image_deref_atomic_umax: |
| case nir_intrinsic_image_deref_atomic_imax: |
| case nir_intrinsic_image_deref_atomic_and: |
| case nir_intrinsic_image_deref_atomic_or: |
| case nir_intrinsic_image_deref_atomic_xor: |
| case nir_intrinsic_image_deref_atomic_exchange: |
| case nir_intrinsic_image_deref_atomic_comp_swap: |
| case nir_intrinsic_image_deref_size: |
| case nir_intrinsic_image_deref_samples: |
| if ((types & nir_lower_non_uniform_image_access) && |
| lower_non_uniform_access_intrin(&b, intrin, 0)) |
| progress = true; |
| break; |
| |
| default: |
| /* Nothing to do */ |
| break; |
| } |
| break; |
| } |
| |
| default: |
| /* Nothing to do */ |
| break; |
| } |
| } |
| } |
| |
| if (progress) |
| nir_metadata_preserve(impl, nir_metadata_none); |
| |
| return progress; |
| } |
| |
| /** |
| * Lowers non-uniform resource access by using a loop |
| * |
| * This pass lowers non-uniform resource access by using subgroup operations |
| * and a loop. Most hardware requires things like textures and UBO access |
| * operations to happen on a dynamically uniform (or at least subgroup |
| * uniform) resource. This pass allows for non-uniform access by placing the |
| * texture instruction in a loop that looks something like this: |
| * |
| * loop { |
| * bool tex_eq_first = readFirstInvocationARB(texture) == texture; |
| * bool smp_eq_first = readFirstInvocationARB(sampler) == sampler; |
| * if (tex_eq_first && smp_eq_first) { |
| * res = texture(texture, sampler, ...); |
| * break; |
| * } |
| * } |
| * |
| * Fortunately, because the instruction is immediately followed by the only |
| * break in the loop, the block containing the instruction dominates the end |
| * of the loop. Therefore, it's safe to move the instruction into the loop |
| * without fixing up SSA in any way. |
| */ |
| bool |
| nir_lower_non_uniform_access(nir_shader *shader, |
| enum nir_lower_non_uniform_access_type types) |
| { |
| bool progress = false; |
| |
| nir_foreach_function(function, shader) { |
| if (function->impl && |
| nir_lower_non_uniform_access_impl(function->impl, types)) |
| progress = true; |
| } |
| |
| return progress; |
| } |
