st/glsl_to_tgsi: simpler fixup of empty writemasks

Empty writemasks mean "copy everything", so we can always just use the number
of vector elements (which uses the GLSL meaning here, i.e. each double is a
single element/writemask bit).

Reviewed-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Reviewed-by: Dave Airlie <airlied@redhat.com>

diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
index da7b83b7f08f65a609eddd4d053265e4890c7760..6a63e5c6ec08fa228f4f9af12dbd2e0ed331bf85 100644 (file)
--- a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
+++ b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
@@ -2842,33 +2842,7 @@ glsl_to_tgsi_visitor::visit(ir_assignment *ir)
 
    l = get_assignment_lhs(ir->lhs, this);
 
-   /* FINISHME: This should really set to the correct maximal writemask for each
-    * FINISHME: component written (in the loops below).  This case can only
-    * FINISHME: occur for matrices, arrays, and structures.
-    */
-   if (ir->write_mask == 0) {
-      assert(!ir->lhs->type->is_scalar() && !ir->lhs->type->is_vector());
-
-      if (ir->lhs->type->is_array() || ir->lhs->type->without_array()->is_matrix()) {
-         if (ir->lhs->type->without_array()->is_64bit()) {
-            switch (ir->lhs->type->without_array()->vector_elements) {
-            case 1:
-               l.writemask = WRITEMASK_X;
-               break;
-            case 2:
-               l.writemask = WRITEMASK_XY;
-               break;
-            case 3:
-               l.writemask = WRITEMASK_XYZ;
-               break;
-            case 4:
-               l.writemask = WRITEMASK_XYZW;
-               break;
-            }
-         } else
-            l.writemask = WRITEMASK_XYZW;
-      }
-   } else {
+   {
       int swizzles[4];
       int first_enabled_chan = 0;
       int rhs_chan = 0;
@@ -2887,6 +2861,15 @@ glsl_to_tgsi_visitor::visit(ir_assignment *ir)
             assert(variable->data.location == FRAG_RESULT_STENCIL);
             l.writemask = WRITEMASK_Y;
          }
+      } else if (ir->write_mask == 0) {
+         assert(!ir->lhs->type->is_scalar() && !ir->lhs->type->is_vector());
+
+         if (ir->lhs->type->is_array() || ir->lhs->type->is_matrix()) {
+            unsigned num_elements = ir->lhs->type->without_array()->vector_elements;
+            l.writemask = u_bit_consecutive(0, num_elements);
+         } else {
+            l.writemask = WRITEMASK_XYZW;
+         }
       } else {
          l.writemask = ir->write_mask;
       }