[Mesa-dev] [RFC PATCH V3 08/10] i965/fs: Skip channel expressions splitting for interpolation

[Chris Forbes]

The backend will have to do a message send, so we want to keep these in
one piece, just like texture ops.

Signed-off-by: Chris Forbes <chrisf at ijw.co.nz>
---
 .../dri/i965/brw_fs_channel_expressions.cpp        | 28 ++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/brw_fs_channel_expressions.cpp b/src/mesa/drivers/dri/i965/brw_fs_channel_expressions.cpp
index e154441..931eb24 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_channel_expressions.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_channel_expressions.cpp
@@ -75,6 +75,18 @@ channel_expressions_predicate(ir_instruction *ir)
    if (!expr)
       return false;
 
+   switch (expr->operation) {
+      /* these opcodes need to act on the whole vector,
+       * just like texturing.
+       */
+      case ir_unop_interpolate_at_centroid:
+      case ir_binop_interpolate_at_offset:
+      case ir_binop_interpolate_at_sample:
+         return false;
+      default:
+         break;
+   }
+
    for (i = 0; i < expr->get_num_operands(); i++) {
       if (expr->operands[i]->type->is_vector())
 	 return true;
@@ -153,6 +165,16 @@ ir_channel_expressions_visitor::visit_leave(ir_assignment *ir)
    if (!found_vector)
       return visit_continue;
 
+   switch (expr->operation) {
+      case ir_unop_interpolate_at_centroid:
+      case ir_binop_interpolate_at_offset:
+      case ir_binop_interpolate_at_sample:
+         return visit_continue;
+
+      default:
+         break;
+   }
+
    /* Store the expression operands in temps so we can use them
     * multiple times.
     */
@@ -420,6 +442,12 @@ ir_channel_expressions_visitor::visit_leave(ir_assignment *ir)
    case ir_binop_pack_half_2x16_split:
       assert(!"not reached: expression operates on scalars only");
       break;
+
+   case ir_unop_interpolate_at_centroid:
+   case ir_binop_interpolate_at_offset:
+   case ir_binop_interpolate_at_sample:
+      assert(!"not reached: these are not split");
+      break;
    }
 
    ir->remove();
-- 
1.8.4.2