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-rw-r--r--src/glsl/nir/nir_opt_peephole_ffma.c268
1 files changed, 0 insertions, 268 deletions
diff --git a/src/glsl/nir/nir_opt_peephole_ffma.c b/src/glsl/nir/nir_opt_peephole_ffma.c
deleted file mode 100644
index 4f0f0da..0000000
--- a/src/glsl/nir/nir_opt_peephole_ffma.c
+++ /dev/null
@@ -1,268 +0,0 @@
-/*
- * Copyright © 2014 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 "nir.h"
-
-/*
- * Implements a small peephole optimization that looks for a multiply that
- * is only ever used in an add and replaces both with an fma.
- */
-
-struct peephole_ffma_state {
- void *mem_ctx;
- nir_function_impl *impl;
- bool progress;
-};
-
-static inline bool
-are_all_uses_fadd(nir_ssa_def *def)
-{
- if (!list_empty(&def->if_uses))
- return false;
-
- nir_foreach_use(def, use_src) {
- nir_instr *use_instr = use_src->parent_instr;
-
- if (use_instr->type != nir_instr_type_alu)
- return false;
-
- nir_alu_instr *use_alu = nir_instr_as_alu(use_instr);
- switch (use_alu->op) {
- case nir_op_fadd:
- break; /* This one's ok */
-
- case nir_op_imov:
- case nir_op_fmov:
- case nir_op_fneg:
- case nir_op_fabs:
- assert(use_alu->dest.dest.is_ssa);
- if (!are_all_uses_fadd(&use_alu->dest.dest.ssa))
- return false;
- break;
-
- default:
- return false;
- }
- }
-
- return true;
-}
-
-static nir_alu_instr *
-get_mul_for_src(nir_alu_src *src, int num_components,
- uint8_t swizzle[4], bool *negate, bool *abs)
-{
- uint8_t swizzle_tmp[4];
- assert(src->src.is_ssa && !src->abs && !src->negate);
-
- nir_instr *instr = src->src.ssa->parent_instr;
- if (instr->type != nir_instr_type_alu)
- return NULL;
-
- nir_alu_instr *alu = nir_instr_as_alu(instr);
- switch (alu->op) {
- case nir_op_imov:
- case nir_op_fmov:
- alu = get_mul_for_src(&alu->src[0], num_components, swizzle, negate, abs);
- break;
-
- case nir_op_fneg:
- alu = get_mul_for_src(&alu->src[0], num_components, swizzle, negate, abs);
- *negate = !*negate;
- break;
-
- case nir_op_fabs:
- alu = get_mul_for_src(&alu->src[0], num_components, swizzle, negate, abs);
- *negate = false;
- *abs = true;
- break;
-
- case nir_op_fmul:
- /* Only absorb a fmul into a ffma if the fmul is is only used in fadd
- * operations. This prevents us from being too aggressive with our
- * fusing which can actually lead to more instructions.
- */
- if (!are_all_uses_fadd(&alu->dest.dest.ssa))
- return NULL;
- break;
-
- default:
- return NULL;
- }
-
- if (!alu)
- return NULL;
-
- /* Copy swizzle data before overwriting it to avoid setting a wrong swizzle.
- *
- * Example:
- * Former swizzle[] = xyzw
- * src->swizzle[] = zyxx
- *
- * Expected output swizzle = zyxx
- * If we reuse swizzle in the loop, then output swizzle would be zyzz.
- */
- memcpy(swizzle_tmp, swizzle, 4*sizeof(uint8_t));
- for (int i = 0; i < num_components; i++)
- swizzle[i] = swizzle_tmp[src->swizzle[i]];
-
- return alu;
-}
-
-static bool
-nir_opt_peephole_ffma_block(nir_block *block, void *void_state)
-{
- struct peephole_ffma_state *state = void_state;
-
- nir_foreach_instr_safe(block, instr) {
- if (instr->type != nir_instr_type_alu)
- continue;
-
- nir_alu_instr *add = nir_instr_as_alu(instr);
- if (add->op != nir_op_fadd)
- continue;
-
- /* TODO: Maybe bail if this expression is considered "precise"? */
-
- assert(add->src[0].src.is_ssa && add->src[1].src.is_ssa);
-
- /* This, is the case a + a. We would rather handle this with an
- * algebraic reduction than fuse it. Also, we want to only fuse
- * things where the multiply is used only once and, in this case,
- * it would be used twice by the same instruction.
- */
- if (add->src[0].src.ssa == add->src[1].src.ssa)
- continue;
-
- nir_alu_instr *mul;
- uint8_t add_mul_src, swizzle[4];
- bool negate, abs;
- for (add_mul_src = 0; add_mul_src < 2; add_mul_src++) {
- for (unsigned i = 0; i < 4; i++)
- swizzle[i] = i;
-
- negate = false;
- abs = false;
-
- mul = get_mul_for_src(&add->src[add_mul_src],
- add->dest.dest.ssa.num_components,
- swizzle, &negate, &abs);
-
- if (mul != NULL)
- break;
- }
-
- if (mul == NULL)
- continue;
-
- nir_ssa_def *mul_src[2];
- mul_src[0] = mul->src[0].src.ssa;
- mul_src[1] = mul->src[1].src.ssa;
-
- if (abs) {
- for (unsigned i = 0; i < 2; i++) {
- nir_alu_instr *abs = nir_alu_instr_create(state->mem_ctx,
- nir_op_fabs);
- abs->src[0].src = nir_src_for_ssa(mul_src[i]);
- nir_ssa_dest_init(&abs->instr, &abs->dest.dest,
- mul_src[i]->num_components, NULL);
- abs->dest.write_mask = (1 << mul_src[i]->num_components) - 1;
- nir_instr_insert_before(&add->instr, &abs->instr);
- mul_src[i] = &abs->dest.dest.ssa;
- }
- }
-
- if (negate) {
- nir_alu_instr *neg = nir_alu_instr_create(state->mem_ctx,
- nir_op_fneg);
- neg->src[0].src = nir_src_for_ssa(mul_src[0]);
- nir_ssa_dest_init(&neg->instr, &neg->dest.dest,
- mul_src[0]->num_components, NULL);
- neg->dest.write_mask = (1 << mul_src[0]->num_components) - 1;
- nir_instr_insert_before(&add->instr, &neg->instr);
- mul_src[0] = &neg->dest.dest.ssa;
- }
-
- nir_alu_instr *ffma = nir_alu_instr_create(state->mem_ctx, nir_op_ffma);
- ffma->dest.saturate = add->dest.saturate;
- ffma->dest.write_mask = add->dest.write_mask;
-
- for (unsigned i = 0; i < 2; i++) {
- ffma->src[i].src = nir_src_for_ssa(mul_src[i]);
- for (unsigned j = 0; j < add->dest.dest.ssa.num_components; j++)
- ffma->src[i].swizzle[j] = mul->src[i].swizzle[swizzle[j]];
- }
- nir_alu_src_copy(&ffma->src[2], &add->src[1 - add_mul_src], ffma);
-
- assert(add->dest.dest.is_ssa);
-
- nir_ssa_dest_init(&ffma->instr, &ffma->dest.dest,
- add->dest.dest.ssa.num_components,
- add->dest.dest.ssa.name);
- nir_ssa_def_rewrite_uses(&add->dest.dest.ssa,
- nir_src_for_ssa(&ffma->dest.dest.ssa));
-
- nir_instr_insert_before(&add->instr, &ffma->instr);
- assert(list_empty(&add->dest.dest.ssa.uses));
- nir_instr_remove(&add->instr);
-
- state->progress = true;
- }
-
- return true;
-}
-
-static bool
-nir_opt_peephole_ffma_impl(nir_function_impl *impl)
-{
- struct peephole_ffma_state state;
-
- state.mem_ctx = ralloc_parent(impl);
- state.impl = impl;
- state.progress = false;
-
- nir_foreach_block(impl, nir_opt_peephole_ffma_block, &state);
-
- if (state.progress)
- nir_metadata_preserve(impl, nir_metadata_block_index |
- nir_metadata_dominance);
-
- return state.progress;
-}
-
-bool
-nir_opt_peephole_ffma(nir_shader *shader)
-{
- bool progress = false;
-
- nir_foreach_overload(shader, overload) {
- if (overload->impl)
- progress |= nir_opt_peephole_ffma_impl(overload->impl);
- }
-
- return progress;
-}
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