From e166003cb7a480fb2672b06201688d4717cbc316 Mon Sep 17 00:00:00 2001 From: Matt Turner Date: Tue, 22 Jan 2019 11:33:11 -0800 Subject: [PATCH] intel/compiler: Reset default flag register in brw_find_live_channel() emit_uniformize() emits SHADER_OPCODE_FIND_LIVE_CHANNEL with its flag_subreg set, so that the IR knows which flag is accessed. However the flag is only used on Gen7 in Align1 mode. To avoid setting unnecessary bits in the instruction words, get the information we need and reset the default flag register. This allows round-tripping through the assembler/disassembler. Reviewed-by: Francisco Jerez --- src/intel/compiler/brw_eu_emit.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/src/intel/compiler/brw_eu_emit.c b/src/intel/compiler/brw_eu_emit.c index 0b4cd4dc213..7772bcd82d2 100644 --- a/src/intel/compiler/brw_eu_emit.c +++ b/src/intel/compiler/brw_eu_emit.c @@ -3309,6 +3309,14 @@ brw_find_live_channel(struct brw_codegen *p, struct brw_reg dst, brw_push_insn_state(p); + /* The flag register is only used on Gen7 in align1 mode, so avoid setting + * unnecessary bits in the instruction words, get the information we need + * and reset the default flag register. This allows more instructions to be + * compacted. + */ + const unsigned flag_subreg = p->current->flag_subreg; + brw_set_default_flag_reg(p, 0, 0); + if (brw_get_default_access_mode(p) == BRW_ALIGN_1) { brw_set_default_mask_control(p, BRW_MASK_DISABLE); @@ -3342,8 +3350,7 @@ brw_find_live_channel(struct brw_codegen *p, struct brw_reg dst, */ inst = brw_FBL(p, vec1(dst), exec_mask); } else { - const struct brw_reg flag = brw_flag_reg(p->current->flag_subreg / 2, - p->current->flag_subreg % 2); + const struct brw_reg flag = brw_flag_subreg(flag_subreg); brw_set_default_exec_size(p, BRW_EXECUTE_1); brw_MOV(p, retype(flag, BRW_REGISTER_TYPE_UD), brw_imm_ud(0)); @@ -3363,6 +3370,8 @@ brw_find_live_channel(struct brw_codegen *p, struct brw_reg dst, brw_inst_set_group(devinfo, inst, lower_size * i + 8 * qtr_control); brw_inst_set_cond_modifier(devinfo, inst, BRW_CONDITIONAL_Z); brw_inst_set_exec_size(devinfo, inst, cvt(lower_size) - 1); + brw_inst_set_flag_reg_nr(devinfo, inst, flag_subreg / 2); + brw_inst_set_flag_subreg_nr(devinfo, inst, flag_subreg % 2); } /* Find the first bit set in the exec_size-wide portion of the flag -- 2.30.2