[Mesa-dev] [PATCH 5/9] i965/nir: Emit MUL + ADD for MAD on GEN <= 5

[Jason Ekstrand]

---
 src/mesa/drivers/dri/i965/brw_fs_nir.cpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
index 5da8423..41f9ae2 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
@@ -1234,7 +1234,13 @@ fs_visitor::nir_emit_alu(nir_alu_instr *instr)
       break;
 
    case nir_op_ffma:
-      inst = emit(MAD(result, op[2], op[1], op[0]));
+      if (brw->gen >= 6) {
+         inst = emit(MAD(result, op[2], op[1], op[0]));
+      } else {
+         fs_reg temp = vgrf(glsl_type::float_type);
+         emit(MUL(temp, op[0], op[1]));
+         inst = emit(ADD(result, temp, op[2]));
+      }
       inst->saturate = instr->dest.saturate;
       break;
 
-- 
2.3.2