[Mesa-dev] [PATCH] i965/vs: Move URB entry_size and read_length calculations to compile_vs

[Jason Ekstrand]

This patch applies on top of my previous series to shuffle a bunch of
the compiler code around.

On Thu, Oct 15, 2015 at 12:05 PM, Jason Ekstrand <jason at jlekstrand.net> wrote:
> ---
>  src/mesa/drivers/dri/i965/brw_vec4.cpp | 34 ++++++++++++++++++++++++++++++++++
>  src/mesa/drivers/dri/i965/brw_vs.c     | 34 ----------------------------------
>  2 files changed, 34 insertions(+), 34 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/i965/brw_vec4.cpp b/src/mesa/drivers/dri/i965/brw_vec4.cpp
> index ca4d23a..00e2d63 100644
> --- a/src/mesa/drivers/dri/i965/brw_vec4.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_vec4.cpp
> @@ -1933,6 +1933,40 @@ brw_compile_vs(const struct brw_compiler *compiler, void *log_data,
>  {
>     const unsigned *assembly = NULL;
>
> +   unsigned nr_attributes = _mesa_bitcount_64(prog_data->inputs_read);
> +
> +   /* gl_VertexID and gl_InstanceID are system values, but arrive via an
> +    * incoming vertex attribute.  So, add an extra slot.
> +    */
> +   if (shader->info.system_values_read &
> +       (BITFIELD64_BIT(SYSTEM_VALUE_VERTEX_ID_ZERO_BASE) |
> +        BITFIELD64_BIT(SYSTEM_VALUE_INSTANCE_ID))) {
> +      nr_attributes++;
> +   }
> +
> +   /* The 3DSTATE_VS documentation lists the lower bound on "Vertex URB Entry
> +    * Read Length" as 1 in vec4 mode, and 0 in SIMD8 mode.  Empirically, in
> +    * vec4 mode, the hardware appears to wedge unless we read something.
> +    */
> +   if (compiler->scalar_vs)
> +      prog_data->base.urb_read_length = DIV_ROUND_UP(nr_attributes, 2);
> +   else
> +      prog_data->base.urb_read_length = DIV_ROUND_UP(MAX2(nr_attributes, 1), 2);
> +
> +   prog_data->nr_attributes = nr_attributes;
> +
> +   /* Since vertex shaders reuse the same VUE entry for inputs and outputs
> +    * (overwriting the original contents), we need to make sure the size is
> +    * the larger of the two.
> +    */
> +   const unsigned vue_entries =
> +      MAX2(nr_attributes, (unsigned)prog_data->base.vue_map.num_slots);
> +
> +   if (compiler->devinfo->gen == 6)
> +      prog_data->base.urb_entry_size = DIV_ROUND_UP(vue_entries, 8);
> +   else
> +      prog_data->base.urb_entry_size = DIV_ROUND_UP(vue_entries, 4);
> +
>     if (compiler->scalar_vs) {
>        prog_data->base.dispatch_mode = DISPATCH_MODE_SIMD8;
>
> diff --git a/src/mesa/drivers/dri/i965/brw_vs.c b/src/mesa/drivers/dri/i965/brw_vs.c
> index 6c161d0..c9afc63 100644
> --- a/src/mesa/drivers/dri/i965/brw_vs.c
> +++ b/src/mesa/drivers/dri/i965/brw_vs.c
> @@ -160,40 +160,6 @@ brw_codegen_vs_prog(struct brw_context *brw,
>                         &prog_data.base.vue_map, outputs_written,
>                         prog ? prog->SeparateShader : false);
>
> -   unsigned nr_attributes = _mesa_bitcount_64(prog_data.inputs_read);
> -
> -   /* gl_VertexID and gl_InstanceID are system values, but arrive via an
> -    * incoming vertex attribute.  So, add an extra slot.
> -    */
> -   if (vp->program.Base.SystemValuesRead &
> -       (BITFIELD64_BIT(SYSTEM_VALUE_VERTEX_ID_ZERO_BASE) |
> -        BITFIELD64_BIT(SYSTEM_VALUE_INSTANCE_ID))) {
> -      nr_attributes++;
> -   }
> -
> -   /* The 3DSTATE_VS documentation lists the lower bound on "Vertex URB Entry
> -    * Read Length" as 1 in vec4 mode, and 0 in SIMD8 mode.  Empirically, in
> -    * vec4 mode, the hardware appears to wedge unless we read something.
> -    */
> -   if (brw->intelScreen->compiler->scalar_vs)
> -      prog_data.base.urb_read_length = DIV_ROUND_UP(nr_attributes, 2);
> -   else
> -      prog_data.base.urb_read_length = DIV_ROUND_UP(MAX2(nr_attributes, 1), 2);
> -
> -   prog_data.nr_attributes = nr_attributes;
> -
> -   /* Since vertex shaders reuse the same VUE entry for inputs and outputs
> -    * (overwriting the original contents), we need to make sure the size is
> -    * the larger of the two.
> -    */
> -   const unsigned vue_entries =
> -      MAX2(nr_attributes, prog_data.base.vue_map.num_slots);
> -
> -   if (brw->gen == 6)
> -      prog_data.base.urb_entry_size = DIV_ROUND_UP(vue_entries, 8);
> -   else
> -      prog_data.base.urb_entry_size = DIV_ROUND_UP(vue_entries, 4);
> -
>     if (0) {
>        _mesa_fprint_program_opt(stderr, &vp->program.Base, PROG_PRINT_DEBUG,
>                                true);
> --
> 2.5.0.400.gff86faf
>