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

[Timothy Arceri]

On Tue, 2014-07-01 at 14:45 -0700, Kenneth Graunke wrote:
> 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()) {

Is this ever actually an array??? 

> +         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++;