[Mesa-dev] [PATCH 08/14] intel/compiler: enable shuffle_from_32bit_read at 64-bit gs_input_load

[Jose Maria Casanova Crespo]

This implementation avoids two unneeded MOVs for each 64-bit
component. One was done in the old shuffle, to avoid cases of
src/dst overlap but this is not the case. And the removed MOV
was already being being done in the shuffle.

Copy propagation wasn't able to remove them because shuffle
destination values are defined with partial writes because they
have stride == 2.
---
 src/intel/compiler/brw_fs_nir.cpp | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/intel/compiler/brw_fs_nir.cpp b/src/intel/compiler/brw_fs_nir.cpp
index 780a9e228de..6abc7c0174d 100644
--- a/src/intel/compiler/brw_fs_nir.cpp
+++ b/src/intel/compiler/brw_fs_nir.cpp
@@ -2305,11 +2305,11 @@ fs_visitor::emit_gs_input_load(const fs_reg &dst,
       }
 
       if (type_sz(dst.type) == 8) {
-         shuffle_32bit_load_result_to_64bit_data(
-            bld, tmp_dst, retype(tmp_dst, BRW_REGISTER_TYPE_F), num_components);
-
-         for (unsigned c = 0; c < num_components; c++)
-            bld.MOV(offset(dst, bld, iter * 2 + c), offset(tmp_dst, bld, c));
+         shuffle_from_32bit_read(bld,
+                                 offset(dst, bld, iter * 2),
+                                 retype(tmp_dst, BRW_REGISTER_TYPE_D),
+                                 0,
+                                 num_components);
       }
 
       if (num_iterations > 1) {
-- 
2.17.1