diff options
Diffstat (limited to 'src/intel/compiler/brw_fs_saturate_propagation.cpp')
| -rw-r--r-- | src/intel/compiler/brw_fs_saturate_propagation.cpp | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/src/intel/compiler/brw_fs_saturate_propagation.cpp b/src/intel/compiler/brw_fs_saturate_propagation.cpp new file mode 100644 index 00000000000..1c97a507d8c --- /dev/null +++ b/src/intel/compiler/brw_fs_saturate_propagation.cpp @@ -0,0 +1,156 @@ +/* + * Copyright © 2013 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 "brw_fs.h" +#include "brw_fs_live_variables.h" +#include "brw_cfg.h" + +/** @file brw_fs_saturate_propagation.cpp + * + * Implements a pass that propagates the SAT modifier from a MOV.SAT into the + * instruction that produced the source of the MOV.SAT, thereby allowing the + * MOV's src and dst to be coalesced and the MOV removed. + * + * For instance, + * + * ADD tmp, src0, src1 + * MOV.SAT dst, tmp + * + * would be transformed into + * + * ADD.SAT tmp, src0, src1 + * MOV dst, tmp + */ + +static bool +opt_saturate_propagation_local(fs_visitor *v, bblock_t *block) +{ + bool progress = false; + int ip = block->end_ip + 1; + + foreach_inst_in_block_reverse(fs_inst, inst, block) { + ip--; + + if (inst->opcode != BRW_OPCODE_MOV || + !inst->saturate || + inst->dst.file != VGRF || + inst->dst.type != inst->src[0].type || + inst->src[0].file != VGRF || + inst->src[0].abs) + continue; + + int src_var = v->live_intervals->var_from_reg(inst->src[0]); + int src_end_ip = v->live_intervals->end[src_var]; + + bool interfered = false; + foreach_inst_in_block_reverse_starting_from(fs_inst, scan_inst, inst) { + if (regions_overlap(scan_inst->dst, scan_inst->size_written, + inst->src[0], inst->size_read(0))) { + if (scan_inst->is_partial_write() || + (scan_inst->dst.type != inst->dst.type && + !scan_inst->can_change_types())) + break; + + if (scan_inst->saturate) { + inst->saturate = false; + progress = true; + } else if (src_end_ip == ip || inst->dst.equals(inst->src[0])) { + if (scan_inst->can_do_saturate()) { + if (scan_inst->dst.type != inst->dst.type) { + scan_inst->dst.type = inst->dst.type; + for (int i = 0; i < scan_inst->sources; i++) { + scan_inst->src[i].type = inst->dst.type; + } + } + + if (inst->src[0].negate) { + if (scan_inst->opcode == BRW_OPCODE_MUL) { + scan_inst->src[0].negate = !scan_inst->src[0].negate; + inst->src[0].negate = false; + } else if (scan_inst->opcode == BRW_OPCODE_MAD) { + scan_inst->src[0].negate = !scan_inst->src[0].negate; + scan_inst->src[1].negate = !scan_inst->src[1].negate; + inst->src[0].negate = false; + } else if (scan_inst->opcode == BRW_OPCODE_ADD) { + if (scan_inst->src[1].file == IMM) { + if (!brw_negate_immediate(scan_inst->src[1].type, + &scan_inst->src[1].as_brw_reg())) { + break; + } + } else { + scan_inst->src[1].negate = !scan_inst->src[1].negate; + } + scan_inst->src[0].negate = !scan_inst->src[0].negate; + inst->src[0].negate = false; + } else { + break; + } + } + + scan_inst->saturate = true; + inst->saturate = false; + progress = true; + } + } + break; + } + for (int i = 0; i < scan_inst->sources; i++) { + if (scan_inst->src[i].file == VGRF && + scan_inst->src[i].nr == inst->src[0].nr && + scan_inst->src[i].offset / REG_SIZE == + inst->src[0].offset / REG_SIZE) { + if (scan_inst->opcode != BRW_OPCODE_MOV || + !scan_inst->saturate || + scan_inst->src[0].abs || + scan_inst->src[0].negate || + scan_inst->src[0].abs != inst->src[0].abs || + scan_inst->src[0].negate != inst->src[0].negate) { + interfered = true; + break; + } + } + } + + if (interfered) + break; + } + } + + return progress; +} + +bool +fs_visitor::opt_saturate_propagation() +{ + bool progress = false; + + calculate_live_intervals(); + + foreach_block (block, cfg) { + progress = opt_saturate_propagation_local(this, block) || progress; + } + + /* Live intervals are still valid. */ + + return progress; +} |