| 0,0 → 1,256 |
|---|
| /* |
| * Copyright © 2015 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. |
| * |
| * Authors: |
| * Jason Ekstrand <jason@jlekstrand.net> |
| */ |
| |
| #include "brw_nir.h" |
| |
| /* |
| * This file implements an analysis pass that determines when we have to do |
| * a boolean resolve on Gen <= 5. Instructions that need a boolean resolve |
| * will have the booleans portion of the instr->pass_flags field set to |
| * BRW_NIR_BOOLEAN_NEEDS_RESOLVE. |
| */ |
| |
| |
| /** Returns the resolve status for the given source |
| * |
| * If the source has a parent instruction then the resolve status is the |
| * status of the parent instruction. If the source does not have a parent |
| * instruction then we don't know so we return NON_BOOLEAN. |
| */ |
| static uint8_t |
| get_resolve_status_for_src(nir_src *src) |
| { |
| nir_instr *src_instr = nir_src_get_parent_instr(src); |
| if (src_instr) { |
| uint8_t resolve_status = src_instr->pass_flags & BRW_NIR_BOOLEAN_MASK; |
| |
| /* If the source instruction needs resolve, then from the perspective |
| * of the user, it's a true boolean. |
| */ |
| if (resolve_status == BRW_NIR_BOOLEAN_NEEDS_RESOLVE) |
| resolve_status = BRW_NIR_BOOLEAN_NO_RESOLVE; |
| return resolve_status; |
| } else { |
| return BRW_NIR_NON_BOOLEAN; |
| } |
| } |
| |
| /** Marks the given source as needing a resolve |
| * |
| * If the given source corresponds to an unresolved boolean it marks it as |
| * needing a resolve. Otherwise, we leave it alone. |
| */ |
| static bool |
| src_mark_needs_resolve(nir_src *src, void *void_state) |
| { |
| nir_instr *src_instr = nir_src_get_parent_instr(src); |
| if (src_instr) { |
| uint8_t resolve_status = src_instr->pass_flags & BRW_NIR_BOOLEAN_MASK; |
| |
| /* If the source instruction is unresolved, then mark it as needing |
| * to be resolved. |
| */ |
| if (resolve_status == BRW_NIR_BOOLEAN_UNRESOLVED) { |
| src_instr->pass_flags &= ~BRW_NIR_BOOLEAN_MASK; |
| src_instr->pass_flags |= BRW_NIR_BOOLEAN_NEEDS_RESOLVE; |
| } |
| |
| } |
| |
| return true; |
| } |
| |
| static bool |
| analyze_boolean_resolves_block(nir_block *block, void *void_state) |
| { |
| nir_foreach_instr(block, instr) { |
| switch (instr->type) { |
| case nir_instr_type_alu: { |
| /* For ALU instructions, the resolve status is handled in a |
| * three-step process. |
| * |
| * 1) Look at the instruction type and sources and determine if it |
| * can be left unresolved. |
| * |
| * 2) Look at the destination and see if we have to resolve |
| * anyway. (This is the case if this instruction is not the |
| * only instruction writing to a given register.) |
| * |
| * 3) If the instruction has a resolve status other than |
| * BOOL_UNRESOLVED or BOOL_NEEDS_RESOLVE then we walk through |
| * the sources and ensure that they are also resolved. This |
| * ensures that we don't end up with any stray unresolved |
| * booleans going into ADDs or something like that. |
| */ |
| |
| uint8_t resolve_status; |
| nir_alu_instr *alu = nir_instr_as_alu(instr); |
| switch (alu->op) { |
| case nir_op_flt: |
| case nir_op_ilt: |
| case nir_op_ult: |
| case nir_op_fge: |
| case nir_op_ige: |
| case nir_op_uge: |
| case nir_op_feq: |
| case nir_op_ieq: |
| case nir_op_fne: |
| case nir_op_ine: |
| case nir_op_f2b: |
| case nir_op_i2b: |
| /* This instruction will turn into a CMP when we actually emit |
| * so the result will have to be resolved before it can be used. |
| */ |
| resolve_status = BRW_NIR_BOOLEAN_UNRESOLVED; |
| |
| /* Even though the destination is allowed to be left unresolved, |
| * the sources are treated as regular integers or floats so |
| * they need to be resolved. |
| */ |
| nir_foreach_src(instr, src_mark_needs_resolve, NULL); |
| break; |
| |
| case nir_op_imov: |
| case nir_op_inot: |
| /* This is a single-source instruction. Just copy the resolve |
| * status from the source. |
| */ |
| resolve_status = get_resolve_status_for_src(&alu->src[0].src); |
| break; |
| |
| case nir_op_iand: |
| case nir_op_ior: |
| case nir_op_ixor: { |
| uint8_t src0_status = get_resolve_status_for_src(&alu->src[0].src); |
| uint8_t src1_status = get_resolve_status_for_src(&alu->src[1].src); |
| |
| if (src0_status == src1_status) { |
| resolve_status = src0_status; |
| } else if (src0_status == BRW_NIR_NON_BOOLEAN || |
| src1_status == BRW_NIR_NON_BOOLEAN) { |
| /* If one of the sources is a non-boolean then the whole |
| * thing is a non-boolean. |
| */ |
| resolve_status = BRW_NIR_NON_BOOLEAN; |
| } else { |
| /* At this point one of them is a true boolean and one is a |
| * boolean that needs a resolve. We could either resolve the |
| * unresolved source or we could resolve here. If we resolve |
| * the unresolved source then we get two resolves for the price |
| * of one. Just set this one to BOOLEAN_NO_RESOLVE and we'll |
| * let the code below force a resolve on the unresolved source. |
| */ |
| resolve_status = BRW_NIR_BOOLEAN_NO_RESOLVE; |
| } |
| break; |
| } |
| |
| default: |
| resolve_status = BRW_NIR_NON_BOOLEAN; |
| } |
| |
| /* If the destination is SSA-like, go ahead allow unresolved booleans. |
| * If the destination register doesn't have a well-defined parent_instr |
| * we need to resolve immediately. |
| */ |
| if (alu->dest.dest.reg.reg->parent_instr == NULL && |
| resolve_status == BRW_NIR_BOOLEAN_UNRESOLVED) { |
| resolve_status = BRW_NIR_BOOLEAN_NEEDS_RESOLVE; |
| } |
| |
| instr->pass_flags = (instr->pass_flags & ~BRW_NIR_BOOLEAN_MASK) | |
| resolve_status; |
| |
| /* Finally, resolve sources if it's needed */ |
| switch (resolve_status) { |
| case BRW_NIR_BOOLEAN_NEEDS_RESOLVE: |
| case BRW_NIR_BOOLEAN_UNRESOLVED: |
| /* This instruction is either unresolved or we're doing the |
| * resolve here; leave the sources alone. |
| */ |
| break; |
| |
| case BRW_NIR_BOOLEAN_NO_RESOLVE: |
| case BRW_NIR_NON_BOOLEAN: |
| nir_foreach_src(instr, src_mark_needs_resolve, NULL); |
| break; |
| |
| default: |
| unreachable("Invalid boolean flag"); |
| } |
| |
| break; |
| } |
| |
| case nir_instr_type_load_const: { |
| nir_load_const_instr *load = nir_instr_as_load_const(instr); |
| |
| /* For load_const instructions, it's a boolean exactly when it holds |
| * one of the values NIR_TRUE or NIR_FALSE. |
| * |
| * Since load_const instructions don't have any sources, we don't |
| * have to worry about resolving them. |
| */ |
| instr->pass_flags &= ~BRW_NIR_BOOLEAN_MASK; |
| if (load->value.u[0] == NIR_TRUE || load->value.u[0] == NIR_FALSE) { |
| instr->pass_flags |= BRW_NIR_BOOLEAN_NO_RESOLVE; |
| } else { |
| instr->pass_flags |= BRW_NIR_NON_BOOLEAN; |
| } |
| continue; |
| } |
| |
| default: |
| /* Everything else is an unknown non-boolean value and needs to |
| * have all sources resolved. |
| */ |
| instr->pass_flags = (instr->pass_flags & ~BRW_NIR_BOOLEAN_MASK) | |
| BRW_NIR_NON_BOOLEAN; |
| nir_foreach_src(instr, src_mark_needs_resolve, NULL); |
| continue; |
| } |
| } |
| |
| nir_if *following_if = nir_block_get_following_if(block); |
| if (following_if) |
| src_mark_needs_resolve(&following_if->condition, NULL); |
| |
| return true; |
| } |
| |
| static void |
| analyze_boolean_resolves_impl(nir_function_impl *impl) |
| { |
| nir_foreach_block(impl, analyze_boolean_resolves_block, NULL); |
| } |
| |
| void |
| brw_nir_analyze_boolean_resolves(nir_shader *shader) |
| { |
| nir_foreach_overload(shader, overload) |
| if (overload->impl) |
| analyze_boolean_resolves_impl(overload->impl); |
| } |