[Mesa-dev] [PATCH] compiler/glsl: Fix uniform location counting.

[Matt Turner]

On Thu, Feb 11, 2016 at 8:31 AM, Plamena Manolova
<plamena.manolova at intel.com> wrote:
> This patch moves the calculation of current uniforms to
> link_uniforms, which makes use of UniformRemapTable which
> stores all the reserved uniform locations.
>
> Location assignment for implicit uniforms now tries to use
> any gaps left in the table after the location assignment
> for explicit uniforms. This gives us more space to store more
> uniforms.
>
> Patch is based on earlier patch with following changes/additions:
>
>    1: Move the counting of explicit locations to
>       check_explicit_uniform_locations and then pass
>       the number to link_assign_uniform_locations.
>    2: Count the number of empty slots in UniformRemapTable
>       and store them in a list_head.
>    3: Try to find an empty slot for implicit locations from
>       the list, if that fails resize UniformRemapTable.
>
> Fixes following CTS tests:
>    ES31-CTS.explicit_uniform_location.uniform-loc-mix-with-implicit-max
>    ES31-CTS.explicit_uniform_location.uniform-loc-mix-with-implicit-max-array
>
> Signed-off-by: Tapani Pälli <tapani.palli at intel.com>
> Signed-off-by: Plamena Manolova <plamena.manolova at intel.com>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93696
> ---
>  src/compiler/glsl/link_uniforms.cpp | 79 ++++++++++++++++++++++++++++++++-----
>  src/compiler/glsl/linker.cpp        | 78 +++++++++++++++++++++++++-----------
>  src/compiler/glsl/linker.h          | 17 +++++++-
>  src/mesa/main/mtypes.h              |  8 ++++
>  4 files changed, 147 insertions(+), 35 deletions(-)
>
> diff --git a/src/compiler/glsl/link_uniforms.cpp b/src/compiler/glsl/link_uniforms.cpp
> index 7072c16..8192c21 100644
> --- a/src/compiler/glsl/link_uniforms.cpp
> +++ b/src/compiler/glsl/link_uniforms.cpp
> @@ -1038,9 +1038,36 @@ assign_hidden_uniform_slot_id(const char *name, unsigned hidden_id,
>     uniform_size->map->put(hidden_uniform_start + hidden_id, name);
>  }
>
> +/**
> + * Search through the list of empty blocks to find one that fits the current
> + * uniform.
> + */
> +static int
> +find_empty_block(struct gl_shader_program *prog,
> +                 struct gl_uniform_storage *uniform)
> +{
> +   const unsigned entries = MAX2(1, uniform->array_elements);
> +
> +   list_for_each_entry_safe(struct empty_uniform_block, block,
> +                            &prog->EmptyUniformLocations, link) {

Please use exec_list in glsl code. That means embedding a "struct
exec_node link" in empty_uniform_block instead of a head_link and
iterating with  foreach_list_typed.