[Mesa-dev] [PATCH 4/7] i965/nir: Remove unused indirect handling

[Matt Turner]

On Mon, Nov 23, 2015 at 6:11 PM, Jason Ekstrand <jason at jlekstrand.net> wrote:
> The one and only place where the FS backend allows reladdr is on uniforms.
> For locals, inputs, and outputs, we lower it away before the backend ever
> sees it.  This commit gets rid of the dead indirect handling code.
> ---
>  src/mesa/drivers/dri/i965/brw_fs_nir.cpp | 44 ++++++++------------------------
>  1 file changed, 11 insertions(+), 33 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> index 062ae08..39111ba 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> @@ -1076,28 +1076,6 @@ fs_visitor::nir_emit_undef(const fs_builder &bld, nir_ssa_undef_instr *instr)
>                                                 instr->def.num_components);
>  }
>
> -static fs_reg
> -fs_reg_for_nir_reg(fs_visitor *v, nir_register *nir_reg,
> -                   unsigned base_offset, nir_src *indirect)
> -{
> -   fs_reg reg;
> -
> -   assert(!nir_reg->is_global);
> -
> -   reg = v->nir_locals[nir_reg->index];
> -
> -   reg = offset(reg, v->bld, base_offset * nir_reg->num_components);
> -   if (indirect) {
> -      int multiplier = nir_reg->num_components * (v->dispatch_width / 8);
> -
> -      reg.reladdr = new(v->mem_ctx) fs_reg(v->vgrf(glsl_type::int_type));
> -      v->bld.MUL(*reg.reladdr, v->get_nir_src(*indirect),
> -                 brw_imm_d(multiplier));
> -   }
> -
> -   return reg;
> -}
> -
>  fs_reg
>  fs_visitor::get_nir_src(nir_src src)
>  {
> @@ -1105,8 +1083,10 @@ fs_visitor::get_nir_src(nir_src src)
>     if (src.is_ssa) {
>        reg = nir_ssa_values[src.ssa->index];
>     } else {
> -      reg = fs_reg_for_nir_reg(this, src.reg.reg, src.reg.base_offset,
> -                               src.reg.indirect);
> +      /* We don't handle indirects on locals */
> +      assert(src.reg.indirect == NULL);
> +      reg = offset(nir_locals[src.reg.reg->index], bld,
> +                   src.reg.base_offset * src.reg.reg->num_components);
>     }
>
>     /* to avoid floating-point denorm flushing problems, set the type by
> @@ -1123,10 +1103,12 @@ fs_visitor::get_nir_dest(nir_dest dest)
>        nir_ssa_values[dest.ssa.index] = bld.vgrf(BRW_REGISTER_TYPE_F,
>                                                  dest.ssa.num_components);
>        return nir_ssa_values[dest.ssa.index];
> +   } else {
> +      /* We don't handle indirects on locals */
> +      assert(dest.reg.indirect == NULL);
> +      return offset(nir_locals[dest.reg.reg->index], bld,
> +                    dest.reg.base_offset * dest.reg.reg->num_components);
>     }
> -
> -   return fs_reg_for_nir_reg(this, dest.reg.reg, dest.reg.base_offset,
> -                             dest.reg.indirect);
>  }
>
>  fs_reg
> @@ -2422,7 +2404,7 @@ fs_visitor::nir_emit_intrinsic(const fs_builder &bld, nir_intrinsic_instr *instr
>     }
>
>     case nir_intrinsic_load_input_indirect:
> -      has_indirect = true;
> +      assert(!"Not allowed");

unreachable

>        /* fallthrough */
>     case nir_intrinsic_load_input: {
>        unsigned index = 0;
> @@ -2434,8 +2416,6 @@ fs_visitor::nir_emit_intrinsic(const fs_builder &bld, nir_intrinsic_instr *instr
>              src = offset(retype(nir_inputs, dest.type), bld,
>                           instr->const_index[0] + index);
>           }
> -         if (has_indirect)
> -            src.reladdr = new(mem_ctx) fs_reg(get_nir_src(instr->src[0]));
>           index++;
>
>           bld.MOV(dest, src);
> @@ -2508,7 +2488,7 @@ fs_visitor::nir_emit_intrinsic(const fs_builder &bld, nir_intrinsic_instr *instr
>     }
>
>     case nir_intrinsic_store_output_indirect:
> -      has_indirect = true;
> +      assert(!"Not allowed");

unreachable

>        /* fallthrough */
>     case nir_intrinsic_store_output: {
>        fs_reg src = get_nir_src(instr->src[0]);
> @@ -2516,8 +2496,6 @@ fs_visitor::nir_emit_intrinsic(const fs_builder &bld, nir_intrinsic_instr *instr
>        for (unsigned j = 0; j < instr->num_components; j++) {
>           fs_reg new_dest = offset(retype(nir_outputs, src.type), bld,
>                                    instr->const_index[0] + index);
> -         if (has_indirect)
> -            src.reladdr = new(mem_ctx) fs_reg(get_nir_src(instr->src[1]));
>           index++;
>           bld.MOV(new_dest, src);
>           src = offset(src, bld, 1);
> --
> 2.5.0.400.gff86faf