diff options
| -rw-r--r-- | src/intel/compiler/brw_fs_cmod_propagation.cpp | 137 |
1 files changed, 80 insertions, 57 deletions
diff --git a/src/intel/compiler/brw_fs_cmod_propagation.cpp b/src/intel/compiler/brw_fs_cmod_propagation.cpp index 462e51d504e..2587d62a950 100644 --- a/src/intel/compiler/brw_fs_cmod_propagation.cpp +++ b/src/intel/compiler/brw_fs_cmod_propagation.cpp @@ -49,6 +49,77 @@ */ static bool +cmod_propagate_cmp_to_add(const gen_device_info *devinfo, bblock_t *block, + fs_inst *inst) +{ + bool read_flag = false; + + foreach_inst_in_block_reverse_starting_from(fs_inst, scan_inst, inst) { + /* The extra scope is to prevent compiler errors for gotos crossing a + * variable initializer (cond, below). + */ + { + bool negate; + + if (scan_inst->opcode != BRW_OPCODE_ADD) + goto not_match; + + /* A CMP is basically a subtraction. The result of the + * subtraction must be the same as the result of the addition. + * This means that one of the operands must be negated. So (a + + * b) vs (a == -b) or (a + -b) vs (a == b). + */ + if ((inst->src[0].equals(scan_inst->src[0]) && + inst->src[1].negative_equals(scan_inst->src[1])) || + (inst->src[0].equals(scan_inst->src[1]) && + inst->src[1].negative_equals(scan_inst->src[0]))) { + negate = false; + } else if ((inst->src[0].negative_equals(scan_inst->src[0]) && + inst->src[1].equals(scan_inst->src[1])) || + (inst->src[0].negative_equals(scan_inst->src[1]) && + inst->src[1].equals(scan_inst->src[0]))) { + negate = true; + } else { + goto not_match; + } + + if (scan_inst->is_partial_write() || + scan_inst->exec_size != inst->exec_size) + goto not_match; + + /* From the Sky Lake PRM Vol. 7 "Assigning Conditional Mods": + * + * * Note that the [post condition signal] bits generated at + * the output of a compute are before the .sat. + * + * So we don't have to bail if scan_inst has saturate. + */ + /* Otherwise, try propagating the conditional. */ + const enum brw_conditional_mod cond = + negate ? brw_swap_cmod(inst->conditional_mod) + : inst->conditional_mod; + + if (scan_inst->can_do_cmod() && + ((!read_flag && scan_inst->conditional_mod == BRW_CONDITIONAL_NONE) || + scan_inst->conditional_mod == cond)) { + scan_inst->conditional_mod = cond; + inst->remove(block); + return true; + } + break; + } + + not_match: + if (scan_inst->flags_written()) + break; + + read_flag = read_flag || scan_inst->flags_read(devinfo); + } + + return false; +} + +static bool opt_cmod_propagation_local(const gen_device_info *devinfo, bblock_t *block) { bool progress = false; @@ -90,64 +161,17 @@ opt_cmod_propagation_local(const gen_device_info *devinfo, bblock_t *block) inst->conditional_mod != BRW_CONDITIONAL_NZ) continue; + /* A CMP with a second source of zero can match with anything. A CMP + * with a second source that is not zero can only match with an ADD + * instruction. + */ + if (inst->opcode == BRW_OPCODE_CMP && !inst->src[1].is_zero()) { + progress = cmod_propagate_cmp_to_add(devinfo, block, inst) || progress; + continue; + } + bool read_flag = false; foreach_inst_in_block_reverse_starting_from(fs_inst, scan_inst, inst) { - /* A CMP with a second source of zero can match with anything. A CMP - * with a second source that is not zero can only match with an ADD - * instruction. - */ - if (inst->opcode == BRW_OPCODE_CMP && !inst->src[1].is_zero()) { - bool negate; - - if (scan_inst->opcode != BRW_OPCODE_ADD) - goto not_match; - - /* A CMP is basically a subtraction. The result of the - * subtraction must be the same as the result of the addition. - * This means that one of the operands must be negated. So (a + - * b) vs (a == -b) or (a + -b) vs (a == b). - */ - if ((inst->src[0].equals(scan_inst->src[0]) && - inst->src[1].negative_equals(scan_inst->src[1])) || - (inst->src[0].equals(scan_inst->src[1]) && - inst->src[1].negative_equals(scan_inst->src[0]))) { - negate = false; - } else if ((inst->src[0].negative_equals(scan_inst->src[0]) && - inst->src[1].equals(scan_inst->src[1])) || - (inst->src[0].negative_equals(scan_inst->src[1]) && - inst->src[1].equals(scan_inst->src[0]))) { - negate = true; - } else { - goto not_match; - } - - if (scan_inst->is_partial_write() || - scan_inst->exec_size != inst->exec_size) - goto not_match; - - /* From the Sky Lake PRM Vol. 7 "Assigning Conditional Mods": - * - * * Note that the [post condition signal] bits generated at - * the output of a compute are before the .sat. - * - * So we don't have to bail if scan_inst has saturate. - */ - - /* Otherwise, try propagating the conditional. */ - const enum brw_conditional_mod cond = - negate ? brw_swap_cmod(inst->conditional_mod) - : inst->conditional_mod; - - if (scan_inst->can_do_cmod() && - ((!read_flag && scan_inst->conditional_mod == BRW_CONDITIONAL_NONE) || - scan_inst->conditional_mod == cond)) { - scan_inst->conditional_mod = cond; - inst->remove(block); - progress = true; - } - break; - } - if (regions_overlap(scan_inst->dst, scan_inst->size_written, inst->src[0], inst->size_read(0))) { if (scan_inst->is_partial_write() || @@ -242,7 +266,6 @@ opt_cmod_propagation_local(const gen_device_info *devinfo, bblock_t *block) break; } - not_match: if (scan_inst->flags_written()) break; |