diff options
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_fs.cpp | 79 |
1 files changed, 72 insertions, 7 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp index 914f0619481..b00e2b5726e 100644 --- a/src/mesa/drivers/dri/i965/brw_fs.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp @@ -2282,7 +2282,7 @@ fs_visitor::register_coalesce() int reg_to_offset[MAX_SAMPLER_MESSAGE_SIZE]; fs_inst *mov[MAX_SAMPLER_MESSAGE_SIZE]; - foreach_list_safe(node, &this->instructions) { + foreach_list(node, &this->instructions) { fs_inst *inst = (fs_inst *)node; if (inst->opcode != BRW_OPCODE_MOV || @@ -2305,8 +2305,49 @@ fs_visitor::register_coalesce() int var_to = live_intervals->var_from_reg(&inst->dst); if (live_intervals->vars_interfere(var_from, var_to) && - !inst->dst.equals(inst->src[0])) - continue; + !inst->dst.equals(inst->src[0])) { + + /* We know that the live ranges of A (var_from) and B (var_to) + * interfere because of the ->vars_interfere() call above. If the end + * of B's live range is after the end of A's range, then we know two + * things: + * - the start of B's live range must be in A's live range (since we + * already know the two ranges interfere, this is the only remaining + * possibility) + * - the interference isn't of the form we're looking for (where B is + * entirely inside A) + */ + if (live_intervals->end[var_to] > live_intervals->end[var_from]) + continue; + + bool overwritten = false; + int scan_ip = -1; + + foreach_list(n, &this->instructions) { + fs_inst *scan_inst = (fs_inst *)n; + scan_ip++; + + if (scan_inst->is_control_flow()) { + overwritten = true; + break; + } + + if (scan_ip <= live_intervals->start[var_to]) + continue; + + if (scan_ip > live_intervals->end[var_to]) + break; + + if (scan_inst->dst.equals(inst->dst) || + scan_inst->dst.equals(inst->src[0])) { + overwritten = true; + break; + } + } + + if (overwritten) + continue; + } if (reg_from != inst->src[0].reg) { reg_from = inst->src[0].reg; @@ -2331,9 +2372,18 @@ fs_visitor::register_coalesce() if (channels_remaining) continue; + bool removed = false; for (int i = 0; i < src_size; i++) { - if (mov[i]) - mov[i]->remove(); + if (mov[i]) { + removed = true; + + mov[i]->opcode = BRW_OPCODE_NOP; + mov[i]->conditional_mod = BRW_CONDITIONAL_NONE; + mov[i]->dst = reg_undef; + mov[i]->src[0] = reg_undef; + mov[i]->src[1] = reg_undef; + mov[i]->src[2] = reg_undef; + } } foreach_list(node, &this->instructions) { @@ -2355,11 +2405,26 @@ fs_visitor::register_coalesce() scan_inst->src[j].reg_offset = reg_to_offset[i]; } } - - progress = true; } } } + + if (removed) { + live_intervals->start[var_to] = MIN2(live_intervals->start[var_to], + live_intervals->start[var_from]); + live_intervals->end[var_to] = MAX2(live_intervals->end[var_to], + live_intervals->end[var_from]); + reg_from = -1; + } + } + + foreach_list_safe(node, &this->instructions) { + fs_inst *inst = (fs_inst *)node; + + if (inst->opcode == BRW_OPCODE_NOP) { + inst->remove(); + progress = true; + } } if (progress) |