[Mesa-dev] [PATCH v2 25/32] i965: add cache fallback support using serialized nir

[Timothy Arceri]

IMO you should just do this in brw_link() when its cheap. You will be 
doing the deserialization at draw time here which is not what we want. 
Can also drop the serialized_nir params if you follow my suggestions in 
patch 14.

On 19/10/17 16:32, Jordan Justen wrote:
> If the i965 gen program cannot be loaded from the cache, then we
> fallback to using a serialized nir program.
> 
> This is based on "i965: add cache fallback support" by Timothy Arceri
> <timothy.arceri at collabora.com>. Tim's version was written to fallback
> to compiling from source, and therefore had to be much more complex.
> After Connor and Jason implemented nir serialization, I was able to
> rewrite and greatly simplify this patch.
> 
> Signed-off-by: Jordan Justen <jordan.l.justen at intel.com>
> ---
>   src/mesa/drivers/dri/i965/brw_disk_cache.c | 27 ++++++++++++++++++++++++++-
>   1 file changed, 26 insertions(+), 1 deletion(-)
> 
> diff --git a/src/mesa/drivers/dri/i965/brw_disk_cache.c b/src/mesa/drivers/dri/i965/brw_disk_cache.c
> index d89df846d5..790fad6925 100644
> --- a/src/mesa/drivers/dri/i965/brw_disk_cache.c
> +++ b/src/mesa/drivers/dri/i965/brw_disk_cache.c
> @@ -24,6 +24,7 @@
>   #include "compiler/blob.h"
>   #include "compiler/glsl/ir_uniform.h"
>   #include "compiler/glsl/shader_cache.h"
> +#include "compiler/nir/nir_serialize.h"
>   #include "main/mtypes.h"
>   #include "util/disk_cache.h"
>   #include "util/macros.h"
> @@ -79,6 +80,27 @@ gen_shader_sha1(struct brw_context *brw, struct gl_program *prog,
>      _mesa_sha1_compute(manifest, strlen(manifest), out_sha1);
>   }
>   
> +static void
> +fallback_to_full_recompile(struct brw_context *brw, struct gl_program *prog,
> +                           gl_shader_stage stage)
> +{
> +   prog->program_written_to_cache = false;
> +   if (brw->ctx._Shader->Flags & GLSL_CACHE_INFO) {
> +      fprintf(stderr, "falling back to nir %s.\n",
> +              _mesa_shader_stage_to_abbrev(prog->info.stage));
> +   }
> +
> +   if (!prog->nir) {
> +      assert(prog->serialized_nir && prog->serialized_nir_size > 0);
> +      const struct nir_shader_compiler_options *options =
> +         brw->ctx.Const.ShaderCompilerOptions[stage].NirOptions;
> +      struct blob_reader reader;
> +      blob_reader_init(&reader, prog->serialized_nir,
> +                       prog->serialized_nir_size);
> +      prog->nir = nir_deserialize(NULL, options, &reader);
> +   }
> +}
> +
>   static void
>   read_program_data(struct gl_program *glprog, struct blob_reader *binary,
>                     struct brw_stage_prog_data *prog_data,
> @@ -298,6 +320,9 @@ brw_disk_cache_upload_program(struct brw_context *brw, gl_shader_stage stage)
>          prog->sh.LinkedTransformFeedback->api_enabled)
>         return false;
>   
> +   if (brw->ctx._Shader->Flags & GLSL_CACHE_FALLBACK)
> +      goto FAIL;
> +
>      if (prog->sh.data->LinkStatus != linking_skipped)
>         goto FAIL;
>   
> @@ -311,7 +336,7 @@ brw_disk_cache_upload_program(struct brw_context *brw, gl_shader_stage stage)
>      return true;
>   
>   FAIL:
> -   /*FIXME: Fall back and compile from source here. */
> +   fallback_to_full_recompile(brw, prog, stage);
>      return false;
>   }
>   
>