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

[Jason Ekstrand]

Topi,
Seeing as you're on a roll reviewing my move-the-code patches, mind one more?
--Jason

On Thu, Oct 15, 2015 at 12:06 PM, Jason Ekstrand <jason at jlekstrand.net> wrote:
> 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
>>