[Mesa-stable] [PATCH] st/mesa: set result writemask based on ir type

[Ilia Mirkin]

This prevents textureQueryLevels, which maps as LODQ, from ending up
with a xyzw writemask, which is illegal.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100061
Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
Cc: mesa-stable at lists.freedesktop.org
---

Untested beyond making sure that the shader in the above bug ends up with
a .xy writemask. I don't have access to a reasonable testing rig right now,
would be ideal if someone could give it a run through theirs...

 src/mesa/state_tracker/st_glsl_to_tgsi.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
index af41bdb..63b681f 100644
--- a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
+++ b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
@@ -4165,6 +4165,7 @@ glsl_to_tgsi_visitor::visit(ir_texture *ir)
     */
    result_src = get_temp(ir->type);
    result_dst = st_dst_reg(result_src);
+   result_dst.writemask = (1 << ir->type->vector_elements) - 1;
 
    switch (ir->op) {
    case ir_tex:
-- 
2.10.2