i965/fs: Use the LRP instruction for ir_triop_lrp when possible.

v2 [mattst88]:
   - Add BRW_OPCODE_LRP to list of CSE-able expressions.
   - Fix op_var[] array size.
   - Rename arguments to emit_lrp to (x, y, a) to clear confusion.
   - Add LRP function to brw_fs.cpp/.h.
   - Corrected comment about LRP instruction arguments in emit_lrp.
v3 [mattst88]:
   - Duplicate MAD code for LRP instead of using a function pointer.
   - Check for != GRF instead of == IMM in emit_lrp.
   - Lower LRP on gen < 6.

Reviewed-by: Matt Turner <[email protected]>
Reviewed-by: Eric Anholt <[email protected]>
Signed-off-by: Kenneth Graunke <[email protected]>

1

1 files changed, 14 insertions, 0 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_fs_emit.cpp b/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
index 3d1f3b356a8..a25f594d9d8 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
@@ -1095,6 +1095,20 @@ fs_generator::generate_code(exec_list *instructions)
 	 brw_set_access_mode(p, BRW_ALIGN_1);
 	 break;
 
+      case BRW_OPCODE_LRP:
+	 brw_set_access_mode(p, BRW_ALIGN_16);
+	 if (dispatch_width == 16) {
+	    brw_set_compression_control(p, BRW_COMPRESSION_NONE);
+	    brw_LRP(p, dst, src[0], src[1], src[2]);
+	    brw_set_compression_control(p, BRW_COMPRESSION_2NDHALF);
+	    brw_LRP(p, sechalf(dst), sechalf(src[0]), sechalf(src[1]), sechalf(src[2]));
+	    brw_set_compression_control(p, BRW_COMPRESSION_COMPRESSED);
+	 } else {
+	    brw_LRP(p, dst, src[0], src[1], src[2]);
+	 }
+	 brw_set_access_mode(p, BRW_ALIGN_1);
+	 break;
+
       case BRW_OPCODE_FRC:
 	 brw_FRC(p, dst, src[0]);
 	 break;