A future patch adds support for removing dead writes to the flag
register. This patch simplifies the logic until then.
total instructions in shared programs: 811813 -> 811869 (0.01%)
instructions in affected programs: 3378 -> 3434 (1.66%)
---
src/mesa/drivers/dri/i965/brw_vec4.cpp | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/src/mesa/drivers/dri/i965/brw_vec4.cpp
b/src/mesa/drivers/dri/i965/brw_vec4.cpp
index cb87fec..d07e8c5 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4.cpp
@@ -356,7 +356,11 @@ vec4_visitor::dead_code_eliminate()
inst->dst = dst_reg(retype(brw_null_reg(), inst->dst.type));
break;
default:
- inst->remove();
+ if (inst->writes_flag()) {
+ inst->dst = dst_reg(retype(brw_null_reg(), inst->dst.type));
+ } else {
+ inst->remove();
+ }
break;
}
progress = true;
--
1.8.3.2
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/mesa-dev
