[Mesa-dev] [PATCH 2/5] i965/fs: Add a comment about about an implementation detail.

[Eric Anholt]

I was going to fix the code above like the previous commit, but we already
had that covered (otherwise all our uniform access would have been broken,
unlike just pull constants).
---
 src/mesa/drivers/dri/i965/brw_fs_reg_allocate.cpp |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/brw_fs_reg_allocate.cpp b/src/mesa/drivers/dri/i965/brw_fs_reg_allocate.cpp
index d1147f5..b8936dc 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_reg_allocate.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_reg_allocate.cpp
@@ -310,6 +310,10 @@ fs_visitor::setup_payload_interference(struct ra_graph *g,
        * node.
        */
       for (int j = 0; j < this->virtual_grf_count; j++) {
+         /* Note that we use a <= comparison, unlike virtual_grf_interferes(),
+          * in order to not have to worry about the uniform issue described in
+          * calculate_live_intervals().
+          */
          if (this->virtual_grf_def[j] <= payload_last_use_ip[i] ||
              this->virtual_grf_use[j] <= payload_last_use_ip[i]) {
             ra_add_node_interference(g, first_payload_node + i, j);
-- 
1.7.10.4