[Mesa-dev] [PATCH 08/14] i965/fs: Initialize a builder explicitly in the gen4 send dependency work-arounds.

[Jason Ekstrand]

On Tue, Jul 28, 2015 at 1:23 AM, Francisco Jerez <currojerez at riseup.net> wrote:
> Instead of relying on the default one.  This shouldn't lead to any
> functional changes because DEP_RESOLVE_MOV overrides the execution
> controls of the instruction anyway.

Actually, DEP_RESOLVE_MOV calls half() on the builder which doesn't
make any sense.  I think the pre-builder intention, based on the
comment, was force_uncompressed and to use a SIMD8 instruction so that
it adds as few deps as possible.  I'm not sure what it's actually
doing now.  In any case, saying that it overrides everything isn't
right.

> ---
>  src/mesa/drivers/dri/i965/brw_fs.cpp | 11 +++++++----
>  1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
> index 71d372c..8bc9372 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
> @@ -2827,7 +2827,8 @@ fs_visitor::insert_gen4_pre_send_dependency_workarounds(bblock_t *block,
>        if (block->start() == scan_inst) {
>           for (int i = 0; i < write_len; i++) {
>              if (needs_dep[i])
> -               DEP_RESOLVE_MOV(bld.at(block, inst), first_write_grf + i);
> +               DEP_RESOLVE_MOV(fs_builder(this, block, inst),
> +                               first_write_grf + i);
>           }
>           return;
>        }
> @@ -2843,7 +2844,7 @@ fs_visitor::insert_gen4_pre_send_dependency_workarounds(bblock_t *block,
>              if (reg >= first_write_grf &&
>                  reg < first_write_grf + write_len &&
>                  needs_dep[reg - first_write_grf]) {
> -               DEP_RESOLVE_MOV(bld.at(block, inst), reg);
> +               DEP_RESOLVE_MOV(fs_builder(this, block, inst), reg);
>                 needs_dep[reg - first_write_grf] = false;
>                 if (scan_inst->exec_size == 16)
>                    needs_dep[reg - first_write_grf + 1] = false;
> @@ -2890,7 +2891,8 @@ fs_visitor::insert_gen4_post_send_dependency_workarounds(bblock_t *block, fs_ins
>        if (block->end() == scan_inst) {
>           for (int i = 0; i < write_len; i++) {
>              if (needs_dep[i])
> -               DEP_RESOLVE_MOV(bld.at(block, scan_inst), first_write_grf + i);
> +               DEP_RESOLVE_MOV(fs_builder(this, block, scan_inst),
> +                               first_write_grf + i);
>           }
>           return;
>        }
> @@ -2905,7 +2907,8 @@ fs_visitor::insert_gen4_post_send_dependency_workarounds(bblock_t *block, fs_ins
>            scan_inst->dst.reg >= first_write_grf &&
>            scan_inst->dst.reg < first_write_grf + write_len &&
>            needs_dep[scan_inst->dst.reg - first_write_grf]) {
> -         DEP_RESOLVE_MOV(bld.at(block, scan_inst), scan_inst->dst.reg);
> +         DEP_RESOLVE_MOV(fs_builder(this, block, scan_inst),
> +                         scan_inst->dst.reg);
>           needs_dep[scan_inst->dst.reg - first_write_grf] = false;
>        }
>
> --
> 2.4.6
>