[Mesa-dev] [PATCH 08/12] i965/fs: Implement support for extract_word.

[Iago Toral]

Reviewed-by: Iago Toral Quiroga <itoral at igalia.com>

On Mon, 2016-01-25 at 15:18 -0800, Matt Turner wrote:
> The vec4 backend will lower it.
> ---
>  src/mesa/drivers/dri/i965/brw_defines.h        | 12 ++++++++++++
>  src/mesa/drivers/dri/i965/brw_fs_cse.cpp       |  2 ++
>  src/mesa/drivers/dri/i965/brw_fs_generator.cpp | 22 ++++++++++++++++++++++
>  src/mesa/drivers/dri/i965/brw_fs_nir.cpp       | 16 ++++++++++++++++
>  src/mesa/drivers/dri/i965/brw_shader.cpp       |  4 ++++
>  5 files changed, 56 insertions(+)
> 
> diff --git a/src/mesa/drivers/dri/i965/brw_defines.h b/src/mesa/drivers/dri/i965/brw_defines.h
> index 10a6d39..01e0c99 100644
> --- a/src/mesa/drivers/dri/i965/brw_defines.h
> +++ b/src/mesa/drivers/dri/i965/brw_defines.h
> @@ -1085,6 +1085,18 @@ enum opcode {
>      */
>     SHADER_OPCODE_BROADCAST,
>  
> +   /**
> +    * Pick the byte from its first source register given by the index
> +    * specified as second source.
> +    */
> +   SHADER_OPCODE_EXTRACT_BYTE,
> +
> +   /**
> +    * Pick the word from its first source register given by the index
> +    * specified as second source.
> +    */
> +   SHADER_OPCODE_EXTRACT_WORD,
> +
>     VEC4_OPCODE_MOV_BYTES,
>     VEC4_OPCODE_PACK_BYTES,
>     VEC4_OPCODE_UNPACK_UNIFORM,
> diff --git a/src/mesa/drivers/dri/i965/brw_fs_cse.cpp b/src/mesa/drivers/dri/i965/brw_fs_cse.cpp
> index 3b65a38..cde6566 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs_cse.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_fs_cse.cpp
> @@ -78,6 +78,8 @@ is_expression(const fs_visitor *v, const fs_inst *const inst)
>     case FS_OPCODE_LINTERP:
>     case SHADER_OPCODE_FIND_LIVE_CHANNEL:
>     case SHADER_OPCODE_BROADCAST:
> +   case SHADER_OPCODE_EXTRACT_BYTE:
> +   case SHADER_OPCODE_EXTRACT_WORD:
>     case SHADER_OPCODE_MOV_INDIRECT:
>        return true;
>     case SHADER_OPCODE_RCP:
> diff --git a/src/mesa/drivers/dri/i965/brw_fs_generator.cpp b/src/mesa/drivers/dri/i965/brw_fs_generator.cpp
> index e05622a..1916a99 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs_generator.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_fs_generator.cpp
> @@ -2201,6 +2201,28 @@ fs_generator::generate_code(const cfg_t *cfg, int dispatch_width)
>           brw_broadcast(p, dst, src[0], src[1]);
>           break;
>  
> +      case SHADER_OPCODE_EXTRACT_BYTE: {
> +         assert(src[0].type == BRW_REGISTER_TYPE_D ||
> +                src[0].type == BRW_REGISTER_TYPE_UD);
> +
> +         enum brw_reg_type type =
> +            src[0].type == BRW_REGISTER_TYPE_D ? BRW_REGISTER_TYPE_B
> +                                               : BRW_REGISTER_TYPE_UB;
> +         brw_MOV(p, dst, spread(suboffset(retype(src[0], type), src[1].ud), 4));
> +         break;
> +      }
> +
> +      case SHADER_OPCODE_EXTRACT_WORD: {
> +         assert(src[0].type == BRW_REGISTER_TYPE_D ||
> +                src[0].type == BRW_REGISTER_TYPE_UD);
> +
> +         enum brw_reg_type type =
> +            src[0].type == BRW_REGISTER_TYPE_D ? BRW_REGISTER_TYPE_W
> +                                               : BRW_REGISTER_TYPE_UW;
> +         brw_MOV(p, dst, spread(suboffset(retype(src[0], type), src[1].ud), 2));
> +         break;
> +      }
> +
>        case FS_OPCODE_SET_SAMPLE_ID:
>           generate_set_sample_id(inst, dst, src[0], src[1]);
>           break;
> diff --git a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> index d7bcc1c..3efee50 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> @@ -1075,6 +1075,22 @@ fs_visitor::nir_emit_alu(const fs_builder &bld, nir_alu_instr *instr)
>        inst->predicate = BRW_PREDICATE_NORMAL;
>        break;
>  
> +   case nir_op_extract_ubyte:
> +   case nir_op_extract_ibyte: {
> +      nir_const_value *byte = nir_src_as_const_value(instr->src[1].src);
> +      bld.emit(SHADER_OPCODE_EXTRACT_BYTE,
> +               result, op[0], brw_imm_ud(byte->u[0]));
> +      break;
> +   }
> +
> +   case nir_op_extract_uword:
> +   case nir_op_extract_iword: {
> +      nir_const_value *word = nir_src_as_const_value(instr->src[1].src);
> +      bld.emit(SHADER_OPCODE_EXTRACT_WORD,
> +               result, op[0], brw_imm_ud(word->u[0]));
> +      break;
> +   }
> +
>     default:
>        unreachable("unhandled instruction");
>     }
> diff --git a/src/mesa/drivers/dri/i965/brw_shader.cpp b/src/mesa/drivers/dri/i965/brw_shader.cpp
> index e42601b..6a6efa9 100644
> --- a/src/mesa/drivers/dri/i965/brw_shader.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_shader.cpp
> @@ -312,6 +312,10 @@ brw_instruction_name(enum opcode op)
>     case SHADER_OPCODE_BROADCAST:
>        return "broadcast";
>  
> +   case SHADER_OPCODE_EXTRACT_BYTE:
> +      return "extract_byte";
> +   case SHADER_OPCODE_EXTRACT_WORD:
> +      return "extract_word";
>     case VEC4_OPCODE_MOV_BYTES:
>        return "mov_bytes";
>     case VEC4_OPCODE_PACK_BYTES: