[Mesa-dev] [PATCH] glsl: set the binding value regardless explicit_binding

[Ian Romanick]

On 05/11/2015 03:37 AM, Alejandro Piñeiro wrote:
> Since commit c0cd5b var->data.binding was set only when explicit_binding
> was false, thas was wrong, should be a test to true. This prevented
> to use any binding point different to 0.
> 
> In any case, that if statement is not needed. Right now mesa requires
> all atomic counters to have an explicit binding point. This would match
> the original implementation.
> 
> Cc: 10.4, 10.5 <mesa-stable at lists.freedesktop.org>
      ^^^^^^^^^^ You should put quotes around this, or it treats it as
two separate e-mail addresses.  One is 10.4 (invalid) and the other use
a user named "10.5" at the address mesa-stable at lists.freedesktop.org
(valid).

> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=90175
> ---
> 
> New version based on Timothy Arceri suggestion at the list. Also
> gentle ping for a formal review of the patch.
> 
>  src/glsl/link_atomics.cpp | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/src/glsl/link_atomics.cpp b/src/glsl/link_atomics.cpp
> index 603873a..2cede91 100644
> --- a/src/glsl/link_atomics.cpp
> +++ b/src/glsl/link_atomics.cpp
> @@ -201,8 +201,7 @@ link_assign_atomic_counter_resources(struct gl_context *ctx,
>           gl_uniform_storage *const storage = &prog->UniformStorage[id];
>  
>           mab.Uniforms[j] = id;
> -         if (!var->data.explicit_binding)
> -            var->data.binding = i;
> +         var->data.binding = i;

I don't think this is correct.  If the user specified an explicit
binding, which you correctly assert is required, this will overwrite
that value with some other value.  See src/glsl/ast_to_hir.cpp around
line 2663.  I suspect the value of ir_variable::data.binding is just
getting lost somewhere (probably not being copied), and your change just
fixes it by luck.

What happens if you change your test to use binding 3 instead of 1?

>           storage->atomic_buffer_index = i;
>           storage->offset = var->data.atomic.offset;
>