diff options
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_fs_cmod_propagation.cpp | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_fs_cmod_propagation.cpp b/src/mesa/drivers/dri/i965/brw_fs_cmod_propagation.cpp index ec9f812ea11..c6384ab53cf 100644 --- a/src/mesa/drivers/dri/i965/brw_fs_cmod_propagation.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs_cmod_propagation.cpp @@ -69,8 +69,7 @@ opt_cmod_propagation_local(fs_visitor *v, bblock_t *block) continue; if (inst->opcode == BRW_OPCODE_MOV && - (inst->conditional_mod != BRW_CONDITIONAL_NZ || - inst->src[0].negate)) + inst->conditional_mod != BRW_CONDITIONAL_NZ) continue; bool read_flag = false; @@ -81,15 +80,20 @@ opt_cmod_propagation_local(fs_visitor *v, bblock_t *block) scan_inst->dst.reg_offset != inst->src[0].reg_offset) break; - if (inst->opcode == BRW_OPCODE_MOV) { - if (!scan_inst->writes_flag()) - break; - + /* If the instruction generating inst's source also wrote the + * flag, and inst is doing a simple .nz comparison, then inst + * is redundant - the appropriate value is already in the flag + * register. Delete inst. + */ + if (inst->conditional_mod == BRW_CONDITIONAL_NZ && + !inst->src[0].negate && + scan_inst->writes_flag()) { inst->remove(block); progress = true; break; } + /* Otherwise, try propagating the conditional. */ enum brw_conditional_mod cond = inst->src[0].negate ? brw_swap_cmod(inst->conditional_mod) : inst->conditional_mod; |