示例#1
0
static void
fs_lower_opcode_derivative(struct toy_compiler *tc, struct toy_inst *inst)
{
   struct toy_dst dst[4];
   struct toy_src src[4];
   int i;

   tdst_transpose(inst->dst, dst);
   tsrc_transpose(inst->src[0], src);

   /*
    * Every four fragments are from a 2x2 subspan, with
    *
    *   fragment 1 on the top-left,
    *   fragment 2 on the top-right,
    *   fragment 3 on the bottom-left,
    *   fragment 4 on the bottom-right.
    *
    * DDX should thus produce
    *
    *   dst = src.yyww - src.xxzz
    *
    * and DDY should produce
    *
    *   dst = src.zzww - src.xxyy
    *
    * But since we are in BRW_ALIGN_1, swizzling does not work and we have to
    * play with the region parameters.
    */
   if (inst->opcode == TOY_OPCODE_DDX) {
      for (i = 0; i < 4; i++) {
         struct toy_src left, right;

         left = tsrc_rect(src[i], TOY_RECT_220);
         right = tsrc_offset(left, 0, 1);

         tc_ADD(tc, dst[i], right, tsrc_negate(left));
      }
   }
   else {
      for (i = 0; i < 4; i++) {
         struct toy_src top, bottom;

         /* approximate with dst = src.zzzz - src.xxxx */
         top = tsrc_rect(src[i], TOY_RECT_440);
         bottom = tsrc_offset(top, 0, 2);

         tc_ADD(tc, dst[i], bottom, tsrc_negate(top));
      }
   }

   tc_discard_inst(tc, inst);
}
示例#2
0
static void
gs_COPY1(struct toy_compiler *tc,
         struct toy_dst dst, int dst_ch,
         struct toy_src src, int src_ch)
{
   struct toy_inst *inst;

   inst = tc_MOV(tc,
         tdst_offset(dst, 0, dst_ch),
         tsrc_rect(tsrc_offset(src, 0, src_ch), TOY_RECT_010));
   inst->exec_size = GEN6_EXECSIZE_1;
   inst->mask_ctrl = GEN6_MASKCTRL_NOMASK;
}
示例#3
0
static void
fs_lower_opcode_tgsi_const_gen6(struct fs_compile_context *fcc,
                                struct toy_dst dst, int dim, struct toy_src idx)
{
   const struct toy_dst header =
      tdst_ud(tdst(TOY_FILE_MRF, fcc->first_free_mrf, 0));
   const struct toy_dst global_offset =
      tdst_ud(tdst(TOY_FILE_MRF, fcc->first_free_mrf, 2 * 4));
   const struct toy_src r0 = tsrc_ud(tsrc(TOY_FILE_GRF, 0, 0));
   struct toy_compiler *tc = &fcc->tc;
   unsigned msg_type, msg_ctrl, msg_len;
   struct toy_inst *inst;
   struct toy_src desc;
   struct toy_dst tmp, real_dst[4];
   int i;

   /* set message header */
   inst = tc_MOV(tc, header, r0);
   inst->mask_ctrl = BRW_MASK_DISABLE;

   /* set global offset */
   inst = tc_MOV(tc, global_offset, idx);
   inst->mask_ctrl = BRW_MASK_DISABLE;
   inst->exec_size = BRW_EXECUTE_1;
   inst->src[0].rect = TOY_RECT_010;

   msg_type = BRW_DATAPORT_READ_MESSAGE_OWORD_BLOCK_READ;
   msg_ctrl = BRW_DATAPORT_OWORD_BLOCK_1_OWORDLOW << 8;
   msg_len = 1;

   desc = tsrc_imm_mdesc_data_port(tc, false, msg_len, 1, true, false,
         msg_type, msg_ctrl, ILO_WM_CONST_SURFACE(dim));

   tmp = tc_alloc_tmp(tc);

   tc_SEND(tc, tmp, tsrc_from(header), desc, fcc->const_cache);

   tdst_transpose(dst, real_dst);
   for (i = 0; i < 4; i++) {
      const struct toy_src src =
         tsrc_offset(tsrc_rect(tsrc_from(tmp), TOY_RECT_010), 0, i);

      /* cast to type D to make sure these are raw moves */
      tc_MOV(tc, tdst_d(real_dst[i]), tsrc_d(src));
   }
}
示例#4
0
static void
fs_lower_opcode_tgsi_const_gen7(struct fs_compile_context *fcc,
                                struct toy_dst dst, int dim, struct toy_src idx)
{
   struct toy_compiler *tc = &fcc->tc;
   const struct toy_dst offset =
      tdst_ud(tdst(TOY_FILE_MRF, fcc->first_free_mrf, 0));
   struct toy_src desc;
   struct toy_inst *inst;
   struct toy_dst tmp, real_dst[4];
   int i;

   /*
    * In 4c1fdae0a01b3f92ec03b61aac1d3df500d51fc6, pull constant load was
    * changed from OWord Block Read to ld to increase performance in the
    * classic driver.  Since we use the constant cache instead of the data
    * cache, I wonder if we still want to follow the classic driver.
    */

   /* set offset */
   inst = tc_MOV(tc, offset, tsrc_rect(idx, TOY_RECT_010));
   inst->exec_size = BRW_EXECUTE_8;
   inst->mask_ctrl = BRW_MASK_DISABLE;

   desc = tsrc_imm_mdesc_sampler(tc, 1, 1, false,
         BRW_SAMPLER_SIMD_MODE_SIMD4X2,
         GEN5_SAMPLER_MESSAGE_SAMPLE_LD,
         0,
         ILO_WM_CONST_SURFACE(dim));

   tmp = tc_alloc_tmp(tc);
   inst = tc_SEND(tc, tmp, tsrc_from(offset), desc, BRW_SFID_SAMPLER);
   inst->exec_size = BRW_EXECUTE_8;
   inst->mask_ctrl = BRW_MASK_DISABLE;

   tdst_transpose(dst, real_dst);
   for (i = 0; i < 4; i++) {
      const struct toy_src src =
         tsrc_offset(tsrc_rect(tsrc_from(tmp), TOY_RECT_010), 0, i);

      /* cast to type D to make sure these are raw moves */
      tc_MOV(tc, tdst_d(real_dst[i]), tsrc_d(src));
   }
}
示例#5
0
static bool
gs_compile_passthrough(struct gs_compile_context *gcc)
{
   struct toy_compiler *tc = &gcc->tc;
   struct ilo_shader *sh = gcc->shader;

   gcc->is_static = true;
   gcc->static_data.total_vertices = gcc->in_vue_count;
   gcc->static_data.total_prims = 1;
   gcc->static_data.last_vertex[0] = 1 << (gcc->in_vue_count - 1);

   gs_init_vars(gcc);
   gs_ff_sync(gcc, tdst_d(gcc->vars.tmp), tsrc_imm_d(gcc->static_data.total_prims));
   gs_COPY1(tc, gcc->vars.urb_write_header, 0, tsrc_from(tdst_d(gcc->vars.tmp)), 0);
   if (gcc->write_so)
      gs_COPY4(tc, gcc->vars.so_index, 0, tsrc_from(tdst_d(gcc->vars.tmp)), 1);

   {
      int vert, attr;

      for (vert = 0; vert < gcc->out_vue_min_count; vert++) {
         for (attr = 0; attr < gcc->shader->out.count; attr++) {
            tc_MOV(tc, tdst_from(gcc->vars.tgsi_outs[attr]),
                  tsrc_offset(gcc->payload.vues[vert], attr / 2, (attr % 2) * 4));
         }

         gs_lower_opcode_emit(gcc, NULL);
      }

      gs_lower_opcode_endprim(gcc, NULL);
   }

   if (!gcc->write_vue)
      gs_discard(gcc);

   gs_lower_virtual_opcodes(gcc);

   toy_compiler_legalize_for_ra(tc);
   toy_compiler_optimize(tc);
   toy_compiler_allocate_registers(tc,
         gcc->first_free_grf,
         gcc->last_free_grf,
         1);

   toy_compiler_legalize_for_asm(tc);

   if (tc->fail) {
      ilo_err("failed to translate GS TGSI tokens: %s\n", tc->reason);
      return false;
   }

   if (ilo_debug & ILO_DEBUG_GS) {
      int i;

      ilo_printf("VUE count %d, VUE size %d\n",
            gcc->in_vue_count, gcc->in_vue_size);
      ilo_printf("%srasterizer discard\n",
            (gcc->variant->u.gs.rasterizer_discard) ? "" : "no ");

      for (i = 0; i < gcc->so_info->num_outputs; i++) {
         ilo_printf("SO[%d] = OUT[%d]\n", i,
               gcc->so_info->output[i].register_index);
      }

      ilo_printf("legalized instructions:\n");
      toy_compiler_dump(tc);
      ilo_printf("\n");
   }

   sh->kernel = toy_compiler_assemble(tc, &sh->kernel_size);
   if (!sh->kernel) {
      ilo_err("failed to compile GS: %s\n", tc->reason);
      return false;
   }

   if (ilo_debug & ILO_DEBUG_GS) {
      ilo_printf("disassembly:\n");
      toy_compiler_disassemble(tc->dev, sh->kernel, sh->kernel_size, false);
      ilo_printf("\n");
   }

   return true;
}
示例#6
0
static void
gs_lower_opcode_tgsi_in(struct gs_compile_context *gcc,
                        struct toy_dst dst, int dim, int idx)
{
   struct toy_compiler *tc = &gcc->tc;
   struct toy_src attr;
   int slot, reg = -1, subreg;

   slot = toy_tgsi_find_input(&gcc->tgsi, idx);
   if (slot >= 0) {
      int i;

      for (i = 0; i < gcc->variant->u.gs.num_inputs; i++) {
         if (gcc->variant->u.gs.semantic_names[i] ==
               gcc->tgsi.inputs[slot].semantic_name &&
               gcc->variant->u.gs.semantic_indices[i] ==
               gcc->tgsi.inputs[slot].semantic_index) {
            reg = i / 2;
            subreg = (i % 2) * 4;
            break;
         }
      }
   }

   if (reg < 0) {
      tc_MOV(tc, dst, tsrc_imm_f(0.0f));
      return;
   }

   /* fix vertex ordering for GEN6_3DPRIM_TRISTRIP_REVERSE */
   if (gcc->in_vue_count == 3 && dim < 2) {
      struct toy_inst *inst;

      /* get PrimType */
      inst = tc_AND(tc, tdst_d(gcc->vars.tmp),
            tsrc_offset(gcc->payload.header, 0, 2), tsrc_imm_d(0x1f));
      inst->exec_size = GEN6_EXECSIZE_1;
      inst->src[0] = tsrc_rect(inst->src[0], TOY_RECT_010);
      inst->src[1] = tsrc_rect(inst->src[1], TOY_RECT_010);

      inst = tc_CMP(tc, tdst_null(), tsrc_from(tdst_d(gcc->vars.tmp)),
            tsrc_imm_d(GEN6_3DPRIM_TRISTRIP_REVERSE), GEN6_COND_NZ);
      inst->src[0] = tsrc_rect(inst->src[0], TOY_RECT_010);

      attr = tsrc_offset(gcc->payload.vues[dim], reg, subreg);
      inst = tc_MOV(tc, dst, attr);
      inst->pred_ctrl = GEN6_PREDCTRL_NORMAL;

      /* swap IN[0] and IN[1] for GEN6_3DPRIM_TRISTRIP_REVERSE */
      dim = !dim;

      attr = tsrc_offset(gcc->payload.vues[dim], reg, subreg);
      inst = tc_MOV(tc, dst, attr);
      inst->pred_ctrl = GEN6_PREDCTRL_NORMAL;
      inst->pred_inv = true;
   }
   else {
      attr = tsrc_offset(gcc->payload.vues[dim], reg, subreg);
      tc_MOV(tc, dst, attr);
   }


}
示例#7
0
static void
gs_lower_opcode_emit_so_static(struct gs_compile_context *gcc)
{
   struct toy_compiler *tc = &gcc->tc;
   struct toy_inst *inst;
   int i, j;

   if (gcc->static_data.num_vertices_in_prim < gcc->out_vue_min_count)
      return;

   inst = tc_MOV(tc, tdst_w(gcc->vars.tmp), tsrc_imm_v(0x03020100));
   inst->exec_size = GEN6_EXECSIZE_8;
   inst->mask_ctrl = GEN6_MASKCTRL_NOMASK;

   tc_ADD(tc, tdst_d(gcc->vars.tmp), tsrc_from(tdst_d(gcc->vars.tmp)),
         tsrc_rect(tsrc_from(gcc->vars.so_index), TOY_RECT_010));

   tc_IF(tc, tdst_null(),
         tsrc_rect(tsrc_offset(tsrc_from(tdst_d(gcc->vars.tmp)), 0, gcc->out_vue_min_count - 1), TOY_RECT_010),
         tsrc_rect(tsrc_offset(gcc->payload.svbi, 0, 4), TOY_RECT_010),
         GEN6_COND_LE);
   {
      for (i = 0; i < gcc->out_vue_min_count; i++) {
         for (j = 0; j < gcc->so_info->num_outputs; j++) {
            const int idx = gcc->so_info->output[j].register_index;
            struct toy_src index, out;
            int binding_table_index;
            bool write_commit;

            index = tsrc_d(tsrc_offset(tsrc_from(gcc->vars.tmp), 0, i));

            if (i == gcc->out_vue_min_count - 1) {
               out = gcc->vars.tgsi_outs[idx];
            }
            else {
               /* gcc->vars.buffer_cur also points to the first vertex */
               const int buf =
                  (gcc->vars.buffer_cur + i) % gcc->vars.buffer_needed;

               out = tsrc_offset(tsrc_from(gcc->vars.buffers[buf]), idx, 0);
            }

            out = tsrc_offset(out, 0, gcc->so_info->output[j].start_component);

            /*
             * From the Sandy Bridge PRM, volume 4 part 2, page 19:
             *
             *     "The Kernel must do a write commit on the last write to DAP
             *      prior to a URB_WRITE with End of Thread."
             */
            write_commit =
               (gcc->static_data.num_vertices == gcc->static_data.total_vertices &&
                i == gcc->out_vue_min_count - 1 &&
                j == gcc->so_info->num_outputs - 1);


            binding_table_index = gcc->shader->bt.gen6_so_base + j;

            gs_write_so(gcc, gcc->vars.tmp, index,
                  out, write_commit, binding_table_index);

            /*
             * From the Sandy Bridge PRM, volume 4 part 1, page 168:
             *
             *     "The write commit does not modify the destination register, but
             *      merely clears the dependency associated with the destination
             *      register. Thus, a simple "mov" instruction using the register as a
             *      source is sufficient to wait for the write commit to occur."
             */
            if (write_commit)
               tc_MOV(tc, gcc->vars.tmp, tsrc_from(gcc->vars.tmp));
         }
      }

      /* SONumPrimsWritten occupies the higher word of m0.2 of URB_WRITE */
      tc_ADD(tc, gcc->vars.so_written,
            tsrc_from(gcc->vars.so_written), tsrc_imm_d(1 << 16));
      tc_ADD(tc, gcc->vars.so_index,
            tsrc_from(gcc->vars.so_index), tsrc_imm_d(gcc->out_vue_min_count));
   }
   tc_ENDIF(tc);
}
/**
 * Emit instructions to write the VUE.
 */
static void
vs_write_vue(struct vs_compile_context *vcc)
{
   struct toy_compiler *tc = &vcc->tc;
   struct toy_src outs[PIPE_MAX_SHADER_OUTPUTS];
   struct toy_dst header;
   struct toy_src r0;
   struct toy_inst *inst;
   int sent_attrs, total_attrs;

   header = tdst_ud(tdst(TOY_FILE_MRF, vcc->first_free_mrf, 0));
   r0 = tsrc_ud(tsrc(TOY_FILE_GRF, 0, 0));
   inst = tc_MOV(tc, header, r0);
   inst->mask_ctrl = GEN6_MASKCTRL_NOMASK;

   if (ilo_dev_gen(tc->dev) >= ILO_GEN(7)) {
      inst = tc_OR(tc, tdst_offset(header, 0, 5),
            tsrc_rect(tsrc_offset(r0, 0, 5), TOY_RECT_010),
            tsrc_rect(tsrc_imm_ud(0xff00), TOY_RECT_010));
      inst->exec_size = GEN6_EXECSIZE_1;
      inst->access_mode = GEN6_ALIGN_1;
      inst->mask_ctrl = GEN6_MASKCTRL_NOMASK;
   }

   total_attrs = vs_collect_outputs(vcc, outs);
   sent_attrs = 0;
   while (sent_attrs < total_attrs) {
      struct toy_src desc;
      int mrf = vcc->first_free_mrf + 1, avail_mrf_for_attrs;
      int num_attrs, msg_len, i;
      bool eot;

      num_attrs = total_attrs - sent_attrs;
      eot = true;

      /* see if we need another message */
      avail_mrf_for_attrs = vcc->last_free_mrf - mrf + 1;
      if (num_attrs > avail_mrf_for_attrs) {
         /*
          * From the Sandy Bridge PRM, volume 4 part 2, page 22:
          *
          *     "Offset. This field specifies a destination offset (in 256-bit
          *      units) from the start of the URB entry(s), as referenced by
          *      URB Return Handle n, at which the data (if any) will be
          *      written."
          *
          * As we need to offset the following messages, we must make sure
          * this one writes an even number of attributes.
          */
         num_attrs = avail_mrf_for_attrs & ~1;
         eot = false;
      }

      if (ilo_dev_gen(tc->dev) >= ILO_GEN(7)) {
         /* do not forget about the header */
         msg_len = 1 + num_attrs;
      }
      else {
         /*
          * From the Sandy Bridge PRM, volume 4 part 2, page 26:
          *
          *     "At least 256 bits per vertex (512 bits total, M1 & M2) must
          *      be written.  Writing only 128 bits per vertex (256 bits
          *      total, M1 only) results in UNDEFINED operation."
          *
          *     "[DevSNB] Interleave writes must be in multiples of 256 per
          *      vertex."
          *
          * That is, we must write or appear to write an even number of
          * attributes, starting from two.
          */
         if (num_attrs % 2 && num_attrs == avail_mrf_for_attrs) {
            num_attrs--;
            eot = false;
         }

         msg_len = 1 + align(num_attrs, 2);
      }

      for (i = 0; i < num_attrs; i++)
         tc_MOV(tc, tdst(TOY_FILE_MRF, mrf++, 0), outs[sent_attrs + i]);

      assert(sent_attrs % 2 == 0);
      desc = tsrc_imm_mdesc_urb(tc, eot, msg_len, 0,
            eot, true, false, true, sent_attrs / 2, 0);

      tc_add2(tc, TOY_OPCODE_URB_WRITE, tdst_null(), tsrc_from(header), desc);

      sent_attrs += num_attrs;
   }
}
示例#9
0
static void
fetch_position(struct fs_compile_context *fcc, struct toy_dst dst)
{
   struct toy_compiler *tc = &fcc->tc;
   const struct toy_src src_z =
      tsrc(TOY_FILE_GRF, fcc->payloads[0].source_depth, 0);
   const struct toy_src src_w =
      tsrc(TOY_FILE_GRF, fcc->payloads[0].source_w, 0);
   const int fb_height =
      (fcc->variant->u.fs.fb_height) ? fcc->variant->u.fs.fb_height : 1;
   const bool origin_upper_left =
      (fcc->tgsi.props.fs_coord_origin == TGSI_FS_COORD_ORIGIN_UPPER_LEFT);
   const bool pixel_center_integer =
      (fcc->tgsi.props.fs_coord_pixel_center ==
       TGSI_FS_COORD_PIXEL_CENTER_INTEGER);
   struct toy_src subspan_x, subspan_y;
   struct toy_dst tmp, tmp_uw;
   struct toy_dst real_dst[4];

   tdst_transpose(dst, real_dst);

   subspan_x = tsrc_uw(tsrc(TOY_FILE_GRF, 1, 2 * 4));
   subspan_x = tsrc_rect(subspan_x, TOY_RECT_240);

   subspan_y = tsrc_offset(subspan_x, 0, 1);

   tmp_uw = tdst_uw(tc_alloc_tmp(tc));
   tmp = tc_alloc_tmp(tc);

   /* X */
   tc_ADD(tc, tmp_uw, subspan_x, tsrc_imm_v(0x10101010));
   tc_MOV(tc, tmp, tsrc_from(tmp_uw));
   if (pixel_center_integer)
      tc_MOV(tc, real_dst[0], tsrc_from(tmp));
   else
      tc_ADD(tc, real_dst[0], tsrc_from(tmp), tsrc_imm_f(0.5f));

   /* Y */
   tc_ADD(tc, tmp_uw, subspan_y, tsrc_imm_v(0x11001100));
   tc_MOV(tc, tmp, tsrc_from(tmp_uw));
   if (origin_upper_left && pixel_center_integer) {
      tc_MOV(tc, real_dst[1], tsrc_from(tmp));
   }
   else {
      struct toy_src y = tsrc_from(tmp);
      float offset = 0.0f;

      if (!pixel_center_integer)
         offset += 0.5f;

      if (!origin_upper_left) {
         offset += (float) (fb_height - 1);
         y = tsrc_negate(y);
      }

      tc_ADD(tc, real_dst[1], y, tsrc_imm_f(offset));
   }

   /* Z and W */
   tc_MOV(tc, real_dst[2], src_z);
   tc_INV(tc, real_dst[3], src_w);
}
示例#10
0
/**
 * Emit instructions to write the color buffers (and the depth buffer).
 */
static void
fs_write_fb(struct fs_compile_context *fcc)
{
   struct toy_compiler *tc = &fcc->tc;
   int base_mrf = fcc->first_free_mrf;
   const struct toy_dst header = tdst_ud(tdst(TOY_FILE_MRF, base_mrf, 0));
   bool header_present = false;
   struct toy_src desc;
   unsigned msg_type, ctrl;
   int color_slots[ILO_MAX_DRAW_BUFFERS], num_cbufs;
   int pos_slot = -1, cbuf, i;

   for (i = 0; i < Elements(color_slots); i++)
      color_slots[i] = -1;

   for (i = 0; i < fcc->tgsi.num_outputs; i++) {
      if (fcc->tgsi.outputs[i].semantic_name == TGSI_SEMANTIC_COLOR) {
         assert(fcc->tgsi.outputs[i].semantic_index < Elements(color_slots));
         color_slots[fcc->tgsi.outputs[i].semantic_index] = i;
      }
      else if (fcc->tgsi.outputs[i].semantic_name == TGSI_SEMANTIC_POSITION) {
         pos_slot = i;
      }
   }

   num_cbufs = fcc->variant->u.fs.num_cbufs;
   /* still need to send EOT (and probably depth) */
   if (!num_cbufs)
      num_cbufs = 1;

   /* we need the header to specify the pixel mask or render target */
   if (fcc->tgsi.uses_kill || num_cbufs > 1) {
      const struct toy_src r0 = tsrc_ud(tsrc(TOY_FILE_GRF, 0, 0));
      struct toy_inst *inst;

      inst = tc_MOV(tc, header, r0);
      inst->mask_ctrl = BRW_MASK_DISABLE;
      base_mrf += fcc->num_grf_per_vrf;

      /* this is a two-register header */
      if (fcc->dispatch_mode == GEN6_WM_8_DISPATCH_ENABLE) {
         inst = tc_MOV(tc, tdst_offset(header, 1, 0), tsrc_offset(r0, 1, 0));
         inst->mask_ctrl = BRW_MASK_DISABLE;
         base_mrf += fcc->num_grf_per_vrf;
      }

      header_present = true;
   }

   for (cbuf = 0; cbuf < num_cbufs; cbuf++) {
      const int slot =
         color_slots[(fcc->tgsi.props.fs_color0_writes_all_cbufs) ? 0 : cbuf];
      int mrf = base_mrf, vrf;
      struct toy_src src[4];

      if (slot >= 0) {
         const unsigned undefined_mask =
            fcc->tgsi.outputs[slot].undefined_mask;
         const int index = fcc->tgsi.outputs[slot].index;

         vrf = toy_tgsi_get_vrf(&fcc->tgsi, TGSI_FILE_OUTPUT, 0, index);
         if (vrf >= 0) {
            const struct toy_src tmp = tsrc(TOY_FILE_VRF, vrf, 0);
            tsrc_transpose(tmp, src);
         }
         else {
            /* use (0, 0, 0, 0) */
            tsrc_transpose(tsrc_imm_f(0.0f), src);
         }

         for (i = 0; i < 4; i++) {
            const struct toy_dst dst = tdst(TOY_FILE_MRF, mrf, 0);

            if (undefined_mask & (1 << i))
               src[i] = tsrc_imm_f(0.0f);

            tc_MOV(tc, dst, src[i]);

            mrf += fcc->num_grf_per_vrf;
         }
      }
      else {
         /* use (0, 0, 0, 0) */
         for (i = 0; i < 4; i++) {
            const struct toy_dst dst = tdst(TOY_FILE_MRF, mrf, 0);

            tc_MOV(tc, dst, tsrc_imm_f(0.0f));
            mrf += fcc->num_grf_per_vrf;
         }
      }

      /* select BLEND_STATE[rt] */
      if (cbuf > 0) {
         struct toy_inst *inst;

         inst = tc_MOV(tc, tdst_offset(header, 0, 2), tsrc_imm_ud(cbuf));
         inst->mask_ctrl = BRW_MASK_DISABLE;
         inst->exec_size = BRW_EXECUTE_1;
         inst->src[0].rect = TOY_RECT_010;
      }

      if (cbuf == 0 && pos_slot >= 0) {
         const int index = fcc->tgsi.outputs[pos_slot].index;
         const struct toy_dst dst = tdst(TOY_FILE_MRF, mrf, 0);
         struct toy_src src[4];
         int vrf;

         vrf = toy_tgsi_get_vrf(&fcc->tgsi, TGSI_FILE_OUTPUT, 0, index);
         if (vrf >= 0) {
            const struct toy_src tmp = tsrc(TOY_FILE_VRF, vrf, 0);
            tsrc_transpose(tmp, src);
         }
         else {
            /* use (0, 0, 0, 0) */
            tsrc_transpose(tsrc_imm_f(0.0f), src);
         }

         /* only Z */
         tc_MOV(tc, dst, src[2]);

         mrf += fcc->num_grf_per_vrf;
      }

      msg_type = (fcc->dispatch_mode == GEN6_WM_16_DISPATCH_ENABLE) ?
         BRW_DATAPORT_RENDER_TARGET_WRITE_SIMD16_SINGLE_SOURCE :
         BRW_DATAPORT_RENDER_TARGET_WRITE_SIMD8_SINGLE_SOURCE_SUBSPAN01;

      ctrl = (cbuf == num_cbufs - 1) << 12 |
             msg_type << 8;

      desc = tsrc_imm_mdesc_data_port(tc, cbuf == num_cbufs - 1,
            mrf - fcc->first_free_mrf, 0,
            header_present, false,
            GEN6_DATAPORT_WRITE_MESSAGE_RENDER_TARGET_WRITE,
            ctrl, ILO_WM_DRAW_SURFACE(cbuf));

      tc_add2(tc, TOY_OPCODE_FB_WRITE, tdst_null(),
            tsrc(TOY_FILE_MRF, fcc->first_free_mrf, 0), desc);
   }
}