[Mesa-dev] [PATCH v2] glsl: Fix aggregates with dynamic initializers.

[Kenneth Graunke]

From: Cody Northrop <cody at lunarg.com>

Vectors are falling in to the ir_dereference_array() path.

Without this change, the following glsl aborts the debug driver,
or gets the wrong answer in release:

mat2x2 a = mat2( vec2( 1.0, vertex.x ), vec2( 0.0, 1.0 ) );

Also submitting piglit tests, will reference in bug.

v2: Rebase on Mesa master.

Signed-off-by: Cody Northrop <cody at lunarg.com>
Reviewed-by: Courtney Goeltzenleuchter <courtney at lunarg.com>
Reviewed-by: Kenneth Graunke <kenneth at whitecape.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79373
---
 src/glsl/ast_function.cpp | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

Hi Cody,

Your patch didn't apply to master due to Matt's foreach_list changes;
I did the obvious rebase.  Otherwise, it looks great.  Thanks for fixing
this and improving our tests!

I'll plan to commit this tomorrow unless anyone else has objections.

 --Ken

diff --git a/src/glsl/ast_function.cpp b/src/glsl/ast_function.cpp
index cdb34cc..98288d2 100644
--- a/src/glsl/ast_function.cpp
+++ b/src/glsl/ast_function.cpp
@@ -743,10 +743,20 @@ process_vec_mat_constructor(exec_list *instructions,
 
    int i = 0;
    foreach_in_list(ir_rvalue, rhs, &actual_parameters) {
-      ir_rvalue *lhs = new(ctx) ir_dereference_array(var,
-                                                     new(ctx) ir_constant(i));
+      ir_instruction *assignment = NULL;
+
+      if (var->type->is_array() || var->type->is_matrix()) {
+         ir_rvalue *lhs = new(ctx) ir_dereference_array(var,
+                                             new(ctx) ir_constant(i));
+         assignment = new(ctx) ir_assignment(lhs, rhs, NULL);
+      } else {
+         /* use writemask rather than index for vector */
+         assert(var->type->is_vector());
+         assert(i < 4);
+         ir_dereference *lhs = new(ctx) ir_dereference_variable(var);
+         assignment = new(ctx) ir_assignment(lhs, rhs, NULL, (unsigned)(1 << i));
+      }
 
-      ir_instruction *assignment = new(ctx) ir_assignment(lhs, rhs, NULL);
       instructions->push_tail(assignment);
 
       i++;
-- 
2.0.0