| /* |
| * Copyright © 2019 Red Hat |
| * |
| * 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 "ir3_nir.h" |
| #include "compiler/nir/nir_builder.h" |
| |
| /** |
| * This pass moves varying fetches (and the instructions they depend on |
| * into the start block. |
| * |
| * We need to set the (ei) "end input" flag on the last varying fetch. |
| * And we want to ensure that all threads execute the instruction that |
| * sets (ei). The easiest way to ensure this is to move all varying |
| * fetches into the start block. Which is something we used to get for |
| * free by using lower_all_io_to_temps=true. |
| * |
| * This may come at the cost of additional register usage. OTOH setting |
| * the (ei) flag earlier probably frees up more VS to run. |
| */ |
| |
| |
| typedef struct { |
| nir_shader *shader; |
| nir_block *start_block; |
| struct nir_instr *cursor; |
| } state; |
| |
| static void move_instruction_to_start_block(state *state, nir_instr *instr); |
| |
| static bool |
| move_src(nir_src *src, void *state) |
| { |
| /* At this point we shouldn't have any non-ssa src: */ |
| debug_assert(src->is_ssa); |
| move_instruction_to_start_block(state, src->ssa->parent_instr); |
| return true; |
| } |
| |
| static void |
| move_instruction_to_start_block(state *state, nir_instr *instr) |
| { |
| /* first move (recursively) all src's to ensure they appear before |
| * load*_input that we are trying to move: |
| */ |
| nir_foreach_src(instr, move_src, state); |
| |
| /* and then move the instruction itself: |
| */ |
| exec_node_remove(&instr->node); |
| |
| if (state->cursor) { |
| exec_node_insert_after(&state->cursor->node, &instr->node); |
| } else { |
| exec_list_push_head(&state->start_block->instr_list, &instr->node); |
| } |
| |
| state->cursor = instr; |
| instr->block = state->start_block; |
| } |
| |
| static bool |
| move_varying_inputs_block(state *state, nir_block *block) |
| { |
| bool progress = false; |
| |
| nir_foreach_instr_safe(instr, block) { |
| if (instr->type != nir_instr_type_intrinsic) |
| continue; |
| |
| nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr); |
| |
| switch (intr->intrinsic) { |
| case nir_intrinsic_load_interpolated_input: |
| case nir_intrinsic_load_input: |
| /* TODO any others to handle? */ |
| break; |
| default: |
| continue; |
| } |
| |
| debug_assert(intr->dest.is_ssa); |
| |
| state->cursor = NULL; |
| move_instruction_to_start_block(state, instr); |
| |
| progress = true; |
| } |
| |
| return progress; |
| } |
| |
| bool |
| ir3_nir_move_varying_inputs(nir_shader *shader) |
| { |
| bool progress = false; |
| |
| debug_assert(shader->info.stage == MESA_SHADER_FRAGMENT); |
| |
| nir_foreach_function (function, shader) { |
| state state; |
| |
| if (!function->impl) |
| continue; |
| |
| state.shader = shader; |
| state.start_block = nir_start_block(function->impl); |
| |
| bool progress = false; |
| nir_foreach_block (block, function->impl) { |
| /* don't need to move anything that is already in the first block */ |
| if (block == state.start_block) |
| continue; |
| progress |= move_varying_inputs_block(&state, block); |
| } |
| |
| if (progress) { |
| nir_metadata_preserve(function->impl, |
| nir_metadata_block_index | nir_metadata_dominance); |
| } |
| } |
| |
| return progress; |
| } |