[Mesa-dev] [PATCH 10/12] i965/fs: Reimplement emit_texture() in terms of logical send messages.

[Jason Ekstrand]

On Sat, Jul 18, 2015 at 7:34 AM, Francisco Jerez <currojerez at riseup.net> wrote:
> ---
>  src/mesa/drivers/dri/i965/brw_fs_visitor.cpp | 66 +++++++++++++++++++++-------
>  1 file changed, 49 insertions(+), 17 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
> index 89fcc49..4011639 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
> @@ -861,6 +861,14 @@ fs_visitor::emit_texture(ir_texture_opcode op,
>        }
>     }
>
> +   if (op == ir_query_levels) {
> +      /* textureQueryLevels() is implemented in terms of TXS so we need to
> +       * pass a valid LOD argument.
> +       */
> +      assert(lod.file == BAD_FILE);
> +      lod = fs_reg(0u);

Why can't this go as part of the switch below?  It seems kind of odd
to split the logic up like this.

> +   }
> +
>     if (coordinate.file != BAD_FILE) {
>        /* FINISHME: Texture coordinate rescaling doesn't work with non-constant
>         * samplers.  This should only be a problem with GL_CLAMP on Gen7.
> @@ -873,26 +881,50 @@ fs_visitor::emit_texture(ir_texture_opcode op,
>      * samples, so don't worry about them.
>      */
>     fs_reg dst = vgrf(glsl_type::get_instance(dest_type->base_type, 4, 1));
> +   const fs_reg srcs[] = {
> +      coordinate, shadow_c, lod, lod2,
> +      sample_index, mcs, sampler_reg, offset_value,
> +      fs_reg(coord_components), fs_reg(grad_components)
> +   };
> +   enum opcode opcode;
>
> -   if (devinfo->gen >= 7) {
> -      inst = emit_texture_gen7(op, dst, coordinate, coord_components,
> -                               shadow_c, lod, lod2, grad_components,
> -                               sample_index, mcs, sampler_reg,
> -                               offset_value);
> -   } else if (devinfo->gen >= 5) {
> -      inst = emit_texture_gen5(op, dst, coordinate, coord_components,
> -                               shadow_c, lod, lod2, grad_components,
> -                               sample_index, sampler,
> -                               offset_value.file != BAD_FILE);
> -   } else if (dispatch_width == 16) {
> -      inst = emit_texture_gen4_simd16(op, dst, coordinate, coord_components,
> -                                      shadow_c, lod, sampler);
> -   } else {
> -      inst = emit_texture_gen4(op, dst, coordinate, coord_components,
> -                               shadow_c, lod, lod2, grad_components,
> -                               sampler);
> +   switch (op) {
> +   case ir_tex:
> +      opcode = SHADER_OPCODE_TEX_LOGICAL;
> +      break;
> +   case ir_txb:
> +      opcode = FS_OPCODE_TXB_LOGICAL;
> +      break;
> +   case ir_txl:
> +      opcode = SHADER_OPCODE_TXL_LOGICAL;
> +      break;
> +   case ir_txd:
> +      opcode = SHADER_OPCODE_TXD_LOGICAL;
> +      break;
> +   case ir_txf:
> +      opcode = SHADER_OPCODE_TXF_LOGICAL;
> +      break;
> +   case ir_txf_ms:
> +      opcode = SHADER_OPCODE_TXF_CMS_LOGICAL;
> +      break;
> +   case ir_txs:
> +   case ir_query_levels:
> +      opcode = SHADER_OPCODE_TXS_LOGICAL;
> +      break;
> +   case ir_lod:
> +      opcode = SHADER_OPCODE_LOD_LOGICAL;
> +      break;
> +   case ir_tg4:
> +      opcode = (offset_value.file != BAD_FILE && offset_value.file != IMM ?
> +                SHADER_OPCODE_TG4_OFFSET_LOGICAL : SHADER_OPCODE_TG4_LOGICAL);
> +      break;
> +   default:
> +      unreachable("not reached");

Please choose something more descriptive than "not reached".  How
about "invalid texture opcode"

>     }
>
> +   inst = bld.emit(opcode, dst, srcs, ARRAY_SIZE(srcs));
> +   inst->regs_written = 4 * dispatch_width / 8;
> +
>     if (shadow_c.file != BAD_FILE)
>        inst->shadow_compare = true;
>
> --
> 2.4.3
>