From: Eric Anholt <eric@anholt.net>
Date: Tue, 30 Oct 2012 21:38:41 +0000 (-0700)
Subject: i965/fs: Allow copy-propagation on pull constant load values.
X-Git-Tag: android-x86-4.4-r1~2922
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=545b59b62a65a9cf1121668bd407e3365bbfa296;p=android-x86%2Fexternal-mesa.git

i965/fs: Allow copy-propagation on pull constant load values.

Given that we handle similarly-regioned GRFs registers for our copy
propagation from our UNIFORM file, there's no reason not to allow it.

The shader-db impact is negligible -- +90 instructions total, 2 shaders helped
and 7 hurt (slightly increased register pressure increased spilling), but this
is to prevent regression in other shaders when fixing copy_propagation to
reduce register pressure in the shaders that are hurt here.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
---

diff --git a/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp b/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
index 2fff6888335..73fe1a58a13 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
@@ -52,12 +52,14 @@ fs_visitor::try_copy_propagate(fs_inst *inst, int arg, acp_entry *entry)
    bool has_source_modifiers = entry->src.abs || entry->src.negate;
 
    if (intel->gen == 6 && inst->is_math() &&
-       (has_source_modifiers || entry->src.file == UNIFORM))
+       (has_source_modifiers || entry->src.file == UNIFORM ||
+        entry->src.smear != -1))
       return false;
 
    inst->src[arg].file = entry->src.file;
    inst->src[arg].reg = entry->src.reg;
    inst->src[arg].reg_offset = entry->src.reg_offset;
+   inst->src[arg].smear = entry->src.smear;
 
    if (!inst->src[arg].abs) {
       inst->src[arg].abs = entry->src.abs;
@@ -255,8 +257,7 @@ fs_visitor::opt_copy_propagate_local(void *mem_ctx, bblock_t *block)
 	  !inst->saturate &&
 	  !inst->predicate &&
 	  !inst->force_uncompressed &&
-	  !inst->force_sechalf &&
-	  inst->src[0].smear == -1) {
+	  !inst->force_sechalf) {
 	 acp_entry *entry = ralloc(mem_ctx, acp_entry);
 	 entry->dst = inst->dst;
 	 entry->src = inst->src[0];