SEL and MOV instructions, as long as they don't have source modifiers, are just copying bits around. This commit adds support to copy propagation to switch the type of a SEL or MOV instruction as needed so that it can propagate source modifiers. This is needed because NIR generates integer SEL and MOV instructions whenver it doesn't know what else to generate.
shader-db results with NIR: total FS instructions in shared programs: 4360910 -> 4360186 (-0.02%) FS instructions in affected programs: 59094 -> 58370 (-1.23%) helped: 341 HURT: 0 GAINED: 2 LOST: 0 --- .../drivers/dri/i965/brw_fs_copy_propagation.cpp | 33 +++++++++++++++++++--- 1 file changed, 29 insertions(+), 4 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp b/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp index e8d092c..d321509 100644 --- a/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp @@ -275,6 +275,16 @@ is_logic_op(enum opcode opcode) opcode == BRW_OPCODE_NOT); } +static bool +can_change_source_types(fs_inst *inst) +{ + return !inst->src[0].abs && !inst->src[0].negate && + (inst->opcode == BRW_OPCODE_MOV || + (inst->opcode == BRW_OPCODE_SEL && + inst->conditional_mod == BRW_CONDITIONAL_NONE && + !inst->src[1].abs && !inst->src[1].negate)); +} + bool fs_visitor::try_copy_propagate(fs_inst *inst, int arg, acp_entry *entry) { @@ -346,7 +356,9 @@ fs_visitor::try_copy_propagate(fs_inst *inst, int arg, acp_entry *entry) type_sz(inst->src[arg].type)) % type_sz(entry->src.type) != 0) return false; - if (has_source_modifiers && entry->dst.type != inst->src[arg].type) + if (has_source_modifiers && + entry->dst.type != inst->src[arg].type && + !can_change_source_types(inst)) return false; if (brw->gen >= 8 && (entry->src.negate || entry->src.abs) && @@ -412,9 +424,22 @@ fs_visitor::try_copy_propagate(fs_inst *inst, int arg, acp_entry *entry) break; } - if (!inst->src[arg].abs) { - inst->src[arg].abs = entry->src.abs; - inst->src[arg].negate ^= entry->src.negate; + if (has_source_modifiers) { + if (entry->dst.type != inst->src[arg].type) { + /* We are propagating source modifiers from a MOV with a different + * type. If we got here, then we can just change the source and + * destination types of the instruction and keep going. + */ + assert(can_change_source_types(inst)); + for (int i = 0; i < inst->sources; i++) + inst->src[i].type = entry->dst.type; + inst->dst.type = entry->dst.type; + } + + if (!inst->src[arg].abs) { + inst->src[arg].abs = entry->src.abs; + inst->src[arg].negate ^= entry->src.negate; + } } return true; -- 2.3.4 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev