[Mesa-dev] [PATCH] glsl_to_tgsi: plumb image writable through to driver

[Marek Olšák]

Reviewed-by: Marek Olšák <marek.olsak at amd.com>

Marek

On Mon, Aug 6, 2018 at 2:48 PM, Erik Faye-Lund
<erik.faye-lund at collabora.com> wrote:
> The virgl driver cares about the writable-flag on image definitions,
> because it re-emits GLSL from the TGSI. However, so far it was hardcoded
> to true in glsl_to_tgsi, which cause problems when virglrenderer is
> running on top of GLES 3.1, where not all formats are supported for
> writable images.
>
> Signed-off-by: Erik Faye-Lund <erik.faye-lund at collabora.com>
> ---
>
> This patch is needed for this patch-series in virglrenderer to work
> properly:
>
> https://patchwork.freedesktop.org/series/47775/
>
>  src/mesa/state_tracker/st_glsl_to_tgsi.cpp    | 19 ++++++++++++++-----
>  .../state_tracker/st_glsl_to_tgsi_private.h   |  1 +
>  2 files changed, 15 insertions(+), 5 deletions(-)
>
> diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> index aec5330917..55984ff0c7 100644
> --- a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> +++ b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> @@ -194,6 +194,7 @@ public:
>     int images_used;
>     enum tgsi_texture_type image_targets[PIPE_MAX_SHADER_IMAGES];
>     enum pipe_format image_formats[PIPE_MAX_SHADER_IMAGES];
> +   bool image_wr[PIPE_MAX_SHADER_IMAGES];
>     bool indirect_addr_consts;
>     int wpos_transform_const;
>
> @@ -3678,7 +3679,8 @@ glsl_to_tgsi_visitor::visit_shared_intrinsic(ir_call *ir)
>  static void
>  get_image_qualifiers(ir_dereference *ir, const glsl_type **type,
>                       bool *memory_coherent, bool *memory_volatile,
> -                     bool *memory_restrict, unsigned *image_format)
> +                     bool *memory_restrict, bool *memory_read_only,
> +                     unsigned *image_format)
>  {
>
>     switch (ir->ir_type) {
> @@ -3694,6 +3696,8 @@ get_image_qualifiers(ir_dereference *ir, const glsl_type **type,
>           struct_type->fields.structure[fild_idx].memory_volatile;
>        *memory_restrict =
>           struct_type->fields.structure[fild_idx].memory_restrict;
> +      *memory_read_only =
> +         struct_type->fields.structure[fild_idx].memory_read_only;
>        *image_format =
>           struct_type->fields.structure[fild_idx].image_format;
>        break;
> @@ -3703,7 +3707,7 @@ get_image_qualifiers(ir_dereference *ir, const glsl_type **type,
>        ir_dereference_array *deref_arr = ir->as_dereference_array();
>        get_image_qualifiers((ir_dereference *)deref_arr->array, type,
>                             memory_coherent, memory_volatile, memory_restrict,
> -                           image_format);
> +                           memory_read_only, image_format);
>        break;
>     }
>
> @@ -3714,6 +3718,7 @@ get_image_qualifiers(ir_dereference *ir, const glsl_type **type,
>        *memory_coherent = var->data.memory_coherent;
>        *memory_volatile = var->data.memory_volatile;
>        *memory_restrict = var->data.memory_restrict;
> +      *memory_read_only = var->data.memory_read_only;
>        *image_format = var->data.image_format;
>        break;
>     }
> @@ -3731,12 +3736,13 @@ glsl_to_tgsi_visitor::visit_image_intrinsic(ir_call *ir)
>     ir_dereference *img = (ir_dereference *)param;
>     const ir_variable *imgvar = img->variable_referenced();
>     unsigned sampler_array_size = 1, sampler_base = 0;
> -   bool memory_coherent = false, memory_volatile = false, memory_restrict = false;
> +   bool memory_coherent = false, memory_volatile = false,
> +        memory_restrict = false, memory_read_only = false;
>     unsigned image_format = 0;
>     const glsl_type *type = NULL;
>
>     get_image_qualifiers(img, &type, &memory_coherent, &memory_volatile,
> -                        &memory_restrict, &image_format);
> +                        &memory_restrict, &memory_read_only, &image_format);
>
>     st_src_reg reladdr;
>     st_src_reg image(PROGRAM_IMAGE, 0, GLSL_TYPE_UINT);
> @@ -3875,6 +3881,7 @@ glsl_to_tgsi_visitor::visit_image_intrinsic(ir_call *ir)
>     inst->tex_target = type->sampler_index();
>     inst->image_format = st_mesa_format_to_pipe_format(st_context(ctx),
>           _mesa_get_shader_image_format(image_format));
> +   inst->read_only = memory_read_only;
>
>     if (memory_coherent)
>        inst->buffer_access |= TGSI_MEMORY_COHERENT;
> @@ -4675,6 +4682,7 @@ count_resources(glsl_to_tgsi_visitor *v, gl_program *prog)
>                 v->image_targets[idx] =
>                    st_translate_texture_target(inst->tex_target, false);
>                 v->image_formats[idx] = inst->image_format;
> +               v->image_wr[idx] = !inst->read_only;
>              }
>           }
>        }
> @@ -6770,7 +6778,8 @@ st_translate_program(
>           t->images[i] = ureg_DECL_image(ureg, i,
>                                          program->image_targets[i],
>                                          program->image_formats[i],
> -                                        true, false);
> +                                        program->image_wr[i],
> +                                        false);
>        }
>     }
>
> diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi_private.h b/src/mesa/state_tracker/st_glsl_to_tgsi_private.h
> index fccb7041cf..356d029f47 100644
> --- a/src/mesa/state_tracker/st_glsl_to_tgsi_private.h
> +++ b/src/mesa/state_tracker/st_glsl_to_tgsi_private.h
> @@ -145,6 +145,7 @@ public:
>     unsigned tex_offset_num_offset:3;
>     unsigned dead_mask:4; /**< Used in dead code elimination */
>     unsigned buffer_access:3; /**< bitmask of TGSI_MEMORY_x bits */
> +   unsigned read_only:1;
>
>     const struct tgsi_opcode_info *info;
>
> --
> 2.18.0
>