diff options
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_fs.cpp | 63 |
1 files changed, 53 insertions, 10 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp index ccd9ac1434a..a3ad3756fd5 100644 --- a/src/mesa/drivers/dri/i965/brw_fs.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp @@ -2039,7 +2039,8 @@ bool fs_visitor::compute_to_mrf() { bool progress = false; - int next_ip = 0; + int next_ip = 0, block_size = 0, step = dispatch_width / 8; + fs_inst *block_start = NULL, *block_end = NULL; calculate_live_intervals(); @@ -2053,8 +2054,27 @@ fs_visitor::compute_to_mrf() inst->dst.type != inst->src[0].type || inst->src[0].abs || inst->src[0].negate || !inst->src[0].is_contiguous() || - inst->src[0].subreg_offset) + inst->src[0].subreg_offset) { + block_start = NULL; continue; + } + + /* We're trying to identify a block of GRF-to-MRF MOVs for the purpose + * of rewriting the send that assigned the GRFs to just return in the + * MRFs directly. send can't saturate, so if any of the MOVs do that, + * cancel the block. + */ + if (inst->saturate) { + block_start = NULL; + } else if (block_start && inst->dst.reg == block_end->dst.reg + step && + inst->src[0].reg == block_end->src[0].reg && + inst->src[0].reg_offset == block_end->src[0].reg_offset + 1) { + block_size++; + block_end = inst; + } else if (inst->src[0].reg_offset == 0) { + block_size = 1; + block_start = block_end = inst; + } /* Work out which hardware MRF registers are written by this * instruction. @@ -2097,14 +2117,8 @@ fs_visitor::compute_to_mrf() if (scan_inst->is_partial_write()) break; - /* Things returning more than one register would need us to - * understand coalescing out more than one MOV at a time. - */ - if (scan_inst->regs_written > 1) - break; - - /* SEND instructions can't have MRF as a destination. */ - if (scan_inst->mlen) + /* SEND instructions can't have MRF as a destination before Gen7. */ + if (brw->gen < 7 && scan_inst->mlen) break; if (brw->gen == 6) { @@ -2116,6 +2130,35 @@ fs_visitor::compute_to_mrf() } } + /* We have a contiguous block of mov to MRF that aligns with the + * return registers of a send instruction. Modify the send + * instruction to just return in the MRFs. + */ + if (scan_inst->mlen > 0 && + scan_inst->regs_written == block_size && block_size > 1) { + int i = 0; + + scan_inst->dst.file = MRF; + scan_inst->dst.reg = block_start->dst.reg; + assert(!block_start->saturate); + + for (fs_inst *next, *mov = block_start; + i < block_size; + mov = next, i++) { + next = (fs_inst *) mov->next; + mov->remove(); + } + + progress = true; + break; + } + + /* If the block size we've tracked doesn't match the regs_written + * of the instruction, we can't do anything. + */ + if (scan_inst->regs_written > 1) + break; + if (scan_inst->dst.reg_offset == inst->src[0].reg_offset) { /* Found the creator of our MRF's source value. */ scan_inst->dst.file = MRF; |