r600/sfn: skip copying LOD if the target register is is the same

Signed-off-by: Gert Wollny <gert.wollny@collabora.com>
Reviewed-by: Reviewed-by: Dave Airlie <airlied@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5085>

diff --git a/src/gallium/drivers/r600/sfn/sfn_emittexinstruction.cpp b/src/gallium/drivers/r600/sfn/sfn_emittexinstruction.cpp
index b3c3b06b450880859a44978c53c4242a44ca34e9..1059db8e4f13528703d1bfb5b47a973828ee6e13 100644 (file)
--- a/src/gallium/drivers/r600/sfn/sfn_emittexinstruction.cpp
+++ b/src/gallium/drivers/r600/sfn/sfn_emittexinstruction.cpp
@@ -481,7 +481,8 @@ bool EmitTexInstruction::emit_tex_txf(nir_tex_instr* instr, TexInputs& src)
 
    auto dst = make_dest(*instr);
 
-   emit_instruction(new AluInstruction(op1_mov, src.coord.reg_i(3), src.lod, {alu_write, alu_last_instr}));
+   if (*src.coord.reg_i(3) != *src.lod)
+      emit_instruction(new AluInstruction(op1_mov, src.coord.reg_i(3), src.lod, {alu_write, alu_last_instr}));
 
    auto sampler = get_samplerr_id(instr->sampler_index, src.sampler_deref);
    assert(!sampler.indirect);