[Mesa-dev] [PATCH 04/11] i965/vec4: Fix handling of multiple register reads and writes in split_virtual_grfs().

[Matt Turner]

On Fri, Mar 20, 2015 at 7:50 AM, Francisco Jerez <currojerez at riseup.net> wrote:
> ---
>  src/mesa/drivers/dri/i965/brw_vec4.cpp | 15 ++++++---------
>  1 file changed, 6 insertions(+), 9 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/i965/brw_vec4.cpp b/src/mesa/drivers/dri/i965/brw_vec4.cpp
> index ed9944d..ce02fe3 100644
> --- a/src/mesa/drivers/dri/i965/brw_vec4.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_vec4.cpp
> @@ -1203,15 +1203,12 @@ vec4_visitor::split_virtual_grfs()
>      * to split.
>      */
>     foreach_block_and_inst(block, vec4_instruction, inst, cfg) {
> -      /* If there's a SEND message loading from a GRF on gen7+, it needs to be
> -       * contiguous.
> -       */
> -      if (inst->is_send_from_grf()) {
> -         for (int i = 0; i < 3; i++) {
> -            if (inst->src[i].file == GRF) {
> -               split_grf[inst->src[i].reg] = false;
> -            }
> -         }

Wow, am I reading this right that we weren't setting split_grf[...] =
false for any destinations?

> +      if (inst->dst.file == GRF && inst->regs_written > 1)
> +         split_grf[inst->dst.reg] = false;
> +
> +      for (int i = 0; i < 3; i++) {
> +         if (inst->src[i].file == GRF && inst->regs_read(i) > 1)
> +            split_grf[inst->src[i].reg] = false;
>        }
>     }
>
> --
> 2.1.3