ilo: compile VS/GS/FS with the toy compiler

1 files changed, 1273 insertions, 0 deletions

diff --git a/src/gallium/drivers/ilo/shader/ilo_shader_vs.c b/src/gallium/drivers/ilo/shader/ilo_shader_vs.c
new file mode 100644
index 00000000000..09a7b0424e7
--- /dev/null
+++ b/src/gallium/drivers/ilo/shader/ilo_shader_vs.c
@@ -0,0 +1,1273 @@
+/*
+ * Mesa 3-D graphics library
+ *
+ * Copyright (C) 2012-2013 LunarG, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Authors:
+ *    Chia-I Wu <olv@lunarg.com>
+ */
+
+#include "tgsi/tgsi_dump.h"
+#include "toy_compiler.h"
+#include "toy_tgsi.h"
+#include "toy_legalize.h"
+#include "toy_optimize.h"
+#include "toy_helpers.h"
+#include "ilo_context.h"
+#include "ilo_shader.h"
+
+struct vs_compile_context {
+   struct ilo_shader *shader;
+   const struct ilo_shader_variant *variant;
+
+   struct toy_compiler tc;
+   struct toy_tgsi tgsi;
+   enum brw_message_target const_cache;
+
+   int output_map[PIPE_MAX_SHADER_OUTPUTS];
+
+   int num_grf_per_vrf;
+   int first_const_grf;
+   int first_vue_grf;
+   int first_free_grf;
+   int last_free_grf;
+
+   int first_free_mrf;
+   int last_free_mrf;
+};
+
+static void
+vs_lower_opcode_tgsi_in(struct vs_compile_context *vcc,
+                        struct toy_dst dst, int dim, int idx)
+{
+   struct toy_compiler *tc = &vcc->tc;
+   int slot;
+
+   assert(!dim);
+
+   slot = toy_tgsi_find_input(&vcc->tgsi, idx);
+   if (slot >= 0) {
+      const int first_in_grf = vcc->first_vue_grf +
+         (vcc->shader->in.count - vcc->tgsi.num_inputs);
+      const int grf = first_in_grf + vcc->tgsi.inputs[slot].semantic_index;
+      const struct toy_src src = tsrc(TOY_FILE_GRF, grf, 0);
+
+      tc_MOV(tc, dst, src);
+   }
+   else {
+      /* undeclared input */
+      tc_MOV(tc, dst, tsrc_imm_f(0.0f));
+   }
+}
+
+static void
+vs_lower_opcode_tgsi_const_gen6(struct vs_compile_context *vcc,
+                                struct toy_dst dst, int dim,
+                                struct toy_src idx)
+{
+   const struct toy_dst header =
+      tdst_ud(tdst(TOY_FILE_MRF, vcc->first_free_mrf, 0));
+   const struct toy_dst block_offsets =
+      tdst_ud(tdst(TOY_FILE_MRF, vcc->first_free_mrf + 1, 0));
+   const struct toy_src r0 = tsrc_ud(tsrc(TOY_FILE_GRF, 0, 0));
+   struct toy_compiler *tc = &vcc->tc;
+   unsigned msg_type, msg_ctrl, msg_len;
+   struct toy_inst *inst;
+   struct toy_src desc;
+
+   /* set message header */
+   inst = tc_MOV(tc, header, r0);
+   inst->mask_ctrl = BRW_MASK_DISABLE;
+
+   /* set block offsets */
+   tc_MOV(tc, block_offsets, idx);
+
+   msg_type = GEN6_DATAPORT_READ_MESSAGE_OWORD_DUAL_BLOCK_READ;
+   msg_ctrl = BRW_DATAPORT_OWORD_DUAL_BLOCK_1OWORD << 8;;
+   msg_len = 2;
+
+   desc = tsrc_imm_mdesc_data_port(tc, false, msg_len, 1, true, false,
+         msg_type, msg_ctrl, ILO_VS_CONST_SURFACE(dim));
+
+   tc_SEND(tc, dst, tsrc_from(header), desc, vcc->const_cache);
+}
+
+static void
+vs_lower_opcode_tgsi_const_gen7(struct vs_compile_context *vcc,
+                                struct toy_dst dst, int dim,
+                                struct toy_src idx)
+{
+   struct toy_compiler *tc = &vcc->tc;
+   const struct toy_dst offset =
+      tdst_ud(tdst(TOY_FILE_MRF, vcc->first_free_mrf, 0));
+   struct toy_src desc;
+
+   /*
+    * In 259b65e2e7938de4aab323033cfe2b33369ddb07, pull constant load was
+    * changed from OWord Dual 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 */
+   tc_MOV(tc, offset, idx);
+
+   desc = tsrc_imm_mdesc_sampler(tc, 1, 1, false,
+         BRW_SAMPLER_SIMD_MODE_SIMD4X2,
+         GEN5_SAMPLER_MESSAGE_SAMPLE_LD,
+         0,
+         ILO_VS_CONST_SURFACE(dim));
+
+   tc_SEND(tc, dst, tsrc_from(offset), desc, BRW_SFID_SAMPLER);
+}
+
+static void
+vs_lower_opcode_tgsi_imm(struct vs_compile_context *vcc,
+                         struct toy_dst dst, int idx)
+{
+   const uint32_t *imm;
+   int ch;
+
+   imm = toy_tgsi_get_imm(&vcc->tgsi, idx, NULL);
+
+   for (ch = 0; ch < 4; ch++) {
+      /* raw moves */
+      tc_MOV(&vcc->tc,
+            tdst_writemask(tdst_ud(dst), 1 << ch),
+            tsrc_imm_ud(imm[ch]));
+   }
+}
+
+
+static void
+vs_lower_opcode_tgsi_sv(struct vs_compile_context *vcc,
+                        struct toy_dst dst, int dim, int idx)
+{
+   struct toy_compiler *tc = &vcc->tc;
+   const struct toy_tgsi *tgsi = &vcc->tgsi;
+   int slot;
+
+   assert(!dim);
+
+   slot = toy_tgsi_find_system_value(tgsi, idx);
+   if (slot < 0)
+      return;
+
+   switch (tgsi->system_values[slot].semantic_name) {
+   case TGSI_SEMANTIC_INSTANCEID:
+   case TGSI_SEMANTIC_VERTEXID:
+      /*
+       * In 3DSTATE_VERTEX_ELEMENTS, we prepend an extra vertex element for
+       * the generated IDs, with VID in the X channel and IID in the Y
+       * channel.
+       */
+      {
+         const int grf = vcc->first_vue_grf;
+         const struct toy_src src = tsrc(TOY_FILE_GRF, grf, 0);
+         const enum toy_swizzle swizzle =
+            (tgsi->system_values[slot].semantic_name ==
+             TGSI_SEMANTIC_INSTANCEID) ? TOY_SWIZZLE_Y : TOY_SWIZZLE_X;
+
+         tc_MOV(tc, tdst_d(dst), tsrc_d(tsrc_swizzle1(src, swizzle)));
+      }
+      break;
+   case TGSI_SEMANTIC_PRIMID:
+   default:
+      tc_fail(tc, "unhandled system value");
+      tc_MOV(tc, dst, tsrc_imm_d(0));
+      break;
+   }
+}
+
+static void
+vs_lower_opcode_tgsi_direct(struct vs_compile_context *vcc,
+                            struct toy_inst *inst)
+{
+   struct toy_compiler *tc = &vcc->tc;
+   int dim, idx;
+
+   assert(inst->src[0].file == TOY_FILE_IMM);
+   dim = inst->src[0].val32;
+
+   assert(inst->src[1].file == TOY_FILE_IMM);
+   idx = inst->src[1].val32;
+
+   switch (inst->opcode) {
+   case TOY_OPCODE_TGSI_IN:
+      vs_lower_opcode_tgsi_in(vcc, inst->dst, dim, idx);
+      break;
+   case TOY_OPCODE_TGSI_CONST:
+      if (tc->gen >= ILO_GEN(7))
+         vs_lower_opcode_tgsi_const_gen7(vcc, inst->dst, dim, inst->src[1]);
+      else
+         vs_lower_opcode_tgsi_const_gen6(vcc, inst->dst, dim, inst->src[1]);
+      break;
+   case TOY_OPCODE_TGSI_SV:
+      vs_lower_opcode_tgsi_sv(vcc, inst->dst, dim, idx);
+      break;
+   case TOY_OPCODE_TGSI_IMM:
+      assert(!dim);
+      vs_lower_opcode_tgsi_imm(vcc, inst->dst, idx);
+      break;
+   default:
+      tc_fail(tc, "unhandled TGSI fetch");
+      break;
+   }
+
+   tc_discard_inst(tc, inst);
+}
+
+static void
+vs_lower_opcode_tgsi_indirect(struct vs_compile_context *vcc,
+                              struct toy_inst *inst)
+{
+   struct toy_compiler *tc = &vcc->tc;
+   enum tgsi_file_type file;
+   int dim, idx;
+   struct toy_src indirect_dim, indirect_idx;
+
+   assert(inst->src[0].file == TOY_FILE_IMM);
+   file = inst->src[0].val32;
+
+   assert(inst->src[1].file == TOY_FILE_IMM);
+   dim = inst->src[1].val32;
+   indirect_dim = inst->src[2];
+
+   assert(inst->src[3].file == TOY_FILE_IMM);
+   idx = inst->src[3].val32;
+   indirect_idx = inst->src[4];
+
+   /* no dimension indirection */
+   assert(indirect_dim.file == TOY_FILE_IMM);
+   dim += indirect_dim.val32;
+
+   switch (inst->opcode) {
+   case TOY_OPCODE_TGSI_INDIRECT_FETCH:
+      if (file == TGSI_FILE_CONSTANT) {
+         if (idx) {
+            struct toy_dst tmp = tc_alloc_tmp(tc);
+
+            tc_ADD(tc, tmp, indirect_idx, tsrc_imm_d(idx));
+            indirect_idx = tsrc_from(tmp);
+         }
+
+         if (tc->gen >= ILO_GEN(7))
+            vs_lower_opcode_tgsi_const_gen7(vcc, inst->dst, dim, indirect_idx);
+         else
+            vs_lower_opcode_tgsi_const_gen6(vcc, inst->dst, dim, indirect_idx);
+         break;
+      }
+      /* fall through */
+   case TOY_OPCODE_TGSI_INDIRECT_STORE:
+   default:
+      tc_fail(tc, "unhandled TGSI indirection");
+      break;
+   }
+
+   tc_discard_inst(tc, inst);
+}
+
+/**
+ * Emit instructions to move sampling parameters to the message registers.
+ */
+static int
+vs_add_sampler_params(struct toy_compiler *tc, int msg_type, int base_mrf,
+                      struct toy_src coords, int num_coords,
+                      struct toy_src bias_or_lod, struct toy_src ref_or_si,
+                      struct toy_src ddx, struct toy_src ddy, int num_derivs)
+{
+   const unsigned coords_writemask = (1 << num_coords) - 1;
+   struct toy_dst m[3];
+   int num_params, i;
+
+   assert(num_coords <= 4);
+   assert(num_derivs <= 3 && num_derivs <= num_coords);
+
+   for (i = 0; i < Elements(m); i++)
+      m[i] = tdst(TOY_FILE_MRF, base_mrf + i, 0);
+
+   switch (msg_type) {
+   case GEN5_SAMPLER_MESSAGE_SAMPLE_LOD:
+      tc_MOV(tc, tdst_writemask(m[0], coords_writemask), coords);
+      tc_MOV(tc, tdst_writemask(m[1], TOY_WRITEMASK_X), bias_or_lod);
+      num_params = 5;
+      break;
+   case GEN5_SAMPLER_MESSAGE_SAMPLE_DERIVS:
+      tc_MOV(tc, tdst_writemask(m[0], coords_writemask), coords);
+      tc_MOV(tc, tdst_writemask(m[1], TOY_WRITEMASK_XZ),
+            tsrc_swizzle(ddx, 0, 0, 1, 1));
+      tc_MOV(tc, tdst_writemask(m[1], TOY_WRITEMASK_YW),
+            tsrc_swizzle(ddy, 0, 0, 1, 1));
+      if (num_derivs > 2) {
+         tc_MOV(tc, tdst_writemask(m[2], TOY_WRITEMASK_X),
+               tsrc_swizzle1(ddx, 2));
+         tc_MOV(tc, tdst_writemask(m[2], TOY_WRITEMASK_Y),
+               tsrc_swizzle1(ddy, 2));
+      }
+      num_params = 4 + num_derivs * 2;
+      break;
+   case GEN5_SAMPLER_MESSAGE_SAMPLE_LOD_COMPARE:
+      tc_MOV(tc, tdst_writemask(m[0], coords_writemask), coords);
+      tc_MOV(tc, tdst_writemask(m[1], TOY_WRITEMASK_X), ref_or_si);
+      tc_MOV(tc, tdst_writemask(m[1], TOY_WRITEMASK_Y), bias_or_lod);
+      num_params = 6;
+      break;
+   case GEN5_SAMPLER_MESSAGE_SAMPLE_LD:
+      assert(num_coords <= 3);
+      tc_MOV(tc, tdst_writemask(tdst_d(m[0]), coords_writemask), coords);
+      tc_MOV(tc, tdst_writemask(tdst_d(m[0]), TOY_WRITEMASK_W), bias_or_lod);
+      if (tc->gen >= ILO_GEN(7)) {
+         num_params = 4;
+      }
+      else {
+         tc_MOV(tc, tdst_writemask(tdst_d(m[1]), TOY_WRITEMASK_X), ref_or_si);
+         num_params = 5;
+      }
+      break;
+   case GEN5_SAMPLER_MESSAGE_SAMPLE_RESINFO:
+      tc_MOV(tc, tdst_writemask(tdst_d(m[0]), TOY_WRITEMASK_X), bias_or_lod);
+      num_params = 1;
+      break;
+   default:
+      tc_fail(tc, "unknown sampler opcode");
+      num_params = 0;
+      break;
+   }
+
+   return (num_params + 3) / 4;
+}
+
+/**
+ * Set up message registers and return the message descriptor for sampling.
+ */
+static struct toy_src
+vs_prepare_tgsi_sampling(struct toy_compiler *tc, const struct toy_inst *inst,
+                         int base_mrf, unsigned *ret_sampler_index)
+{
+   unsigned simd_mode, msg_type, msg_len, sampler_index, binding_table_index;
+   struct toy_src coords, ddx, ddy, bias_or_lod, ref_or_si;
+   int num_coords, ref_pos, num_derivs;
+   int sampler_src;
+
+   simd_mode = BRW_SAMPLER_SIMD_MODE_SIMD4X2;
+
+   coords = inst->src[0];
+   ddx = tsrc_null();
+   ddy = tsrc_null();
+   bias_or_lod = tsrc_null();
+   ref_or_si = tsrc_null();
+   num_derivs = 0;
+   sampler_src = 1;
+
+   num_coords = toy_tgsi_get_texture_coord_dim(inst->tex.target, &ref_pos);
+
+   /* extract the parameters */
+   switch (inst->opcode) {
+   case TOY_OPCODE_TGSI_TXD:
+      if (ref_pos >= 0)
+         tc_fail(tc, "TXD with shadow sampler not supported");
+
+      msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_DERIVS;
+      ddx = inst->src[1];
+      ddy = inst->src[2];
+      num_derivs = num_coords;
+      sampler_src = 3;
+      break;
+   case TOY_OPCODE_TGSI_TXL:
+      if (ref_pos >= 0) {
+         assert(ref_pos < 3);
+
+         msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_LOD_COMPARE;
+         ref_or_si = tsrc_swizzle1(coords, ref_pos);
+      }
+      else {
+         msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_LOD;
+      }
+
+      bias_or_lod = tsrc_swizzle1(coords, TOY_SWIZZLE_W);
+      break;
+   case TOY_OPCODE_TGSI_TXF:
+      msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_LD;
+
+      switch (inst->tex.target) {
+      case TGSI_TEXTURE_2D_MSAA:
+      case TGSI_TEXTURE_2D_ARRAY_MSAA:
+         assert(ref_pos >= 0 && ref_pos < 4);
+         /* lod is always 0 */
+         bias_or_lod = tsrc_imm_d(0);
+         ref_or_si = tsrc_swizzle1(coords, ref_pos);
+         break;
+      default:
+         bias_or_lod = tsrc_swizzle1(coords, TOY_SWIZZLE_W);
+         break;
+      }
+
+      /* offset the coordinates */
+      if (!tsrc_is_null(inst->tex.offsets[0])) {
+         struct toy_dst tmp;
+
+         tmp = tc_alloc_tmp(tc);
+         tc_ADD(tc, tmp, coords, inst->tex.offsets[0]);
+         coords = tsrc_from(tmp);
+      }
+
+      sampler_src = 1;
+      break;
+   case TOY_OPCODE_TGSI_TXQ:
+      msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_RESINFO;
+      num_coords = 0;
+      bias_or_lod = tsrc_swizzle1(coords, TOY_SWIZZLE_X);
+      break;
+   case TOY_OPCODE_TGSI_TXQ_LZ:
+      msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_RESINFO;
+      num_coords = 0;
+      sampler_src = 0;
+      break;
+   case TOY_OPCODE_TGSI_TXL2:
+      if (ref_pos >= 0) {
+         assert(ref_pos < 4);
+
+         msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_LOD_COMPARE;
+         ref_or_si = tsrc_swizzle1(coords, ref_pos);
+      }
+      else {
+         msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_LOD;
+      }
+
+      bias_or_lod = tsrc_swizzle1(inst->src[1], TOY_SWIZZLE_X);
+      sampler_src = 2;
+      break;
+   default:
+      assert(!"unhandled sampling opcode");
+      return tsrc_null();
+      break;
+   }
+
+   assert(inst->src[sampler_src].file == TOY_FILE_IMM);
+   sampler_index = inst->src[sampler_src].val32;
+   binding_table_index = ILO_VS_TEXTURE_SURFACE(sampler_index);
+
+   /*
+    * From the Sandy Bridge PRM, volume 4 part 1, page 18:
+    *
+    *     "Note that the (cube map) coordinates delivered to the sampling
+    *      engine must already have been divided by the component with the
+    *      largest absolute value."
+    */
+   switch (inst->tex.target) {
+   case TGSI_TEXTURE_CUBE:
+   case TGSI_TEXTURE_SHADOWCUBE:
+   case TGSI_TEXTURE_CUBE_ARRAY:
+   case TGSI_TEXTURE_SHADOWCUBE_ARRAY:
+      /* TXQ does not need coordinates */
+      if (num_coords >= 3) {
+         struct toy_dst tmp, max;
+         struct toy_src abs_coords[3];
+         int i;
+
+         tmp = tc_alloc_tmp(tc);
+         max = tdst_writemask(tmp, TOY_WRITEMASK_W);
+
+         for (i = 0; i < 3; i++)
+            abs_coords[i] = tsrc_absolute(tsrc_swizzle1(coords, i));
+
+         tc_SEL(tc, max, abs_coords[0], abs_coords[0], BRW_CONDITIONAL_GE);
+         tc_SEL(tc, max, tsrc_from(max), abs_coords[0], BRW_CONDITIONAL_GE);
+         tc_INV(tc, max, tsrc_from(max));
+
+         for (i = 0; i < 3; i++)
+            tc_MUL(tc, tdst_writemask(tmp, 1 << i), coords, tsrc_from(max));
+
+         coords = tsrc_from(tmp);
+      }
+      break;
+   }
+
+   /* set up sampler parameters */
+   msg_len = vs_add_sampler_params(tc, msg_type, base_mrf,
+         coords, num_coords, bias_or_lod, ref_or_si, ddx, ddy, num_derivs);
+
+   /*
+    * From the Sandy Bridge PRM, volume 4 part 1, page 136:
+    *
+    *     "The maximum message length allowed to the sampler is 11. This would
+    *      disallow sample_d, sample_b_c, and sample_l_c with a SIMD Mode of
+    *      SIMD16."
+    */
+   if (msg_len > 11)
+      tc_fail(tc, "maximum length for messages to the sampler is 11");
+
+   if (ret_sampler_index)
+      *ret_sampler_index = sampler_index;
+
+   return tsrc_imm_mdesc_sampler(tc, msg_len, 1,
+         false, simd_mode, msg_type, sampler_index, binding_table_index);
+}
+
+static void
+vs_lower_opcode_tgsi_sampling(struct vs_compile_context *vcc,
+                              struct toy_inst *inst)
+{
+   struct toy_compiler *tc = &vcc->tc;
+   struct toy_src desc;
+   struct toy_dst dst, tmp;
+   unsigned sampler_index;
+   int swizzles[4], i;
+   unsigned swizzle_zero_mask, swizzle_one_mask, swizzle_normal_mask;
+   bool need_filter;
+
+   desc = vs_prepare_tgsi_sampling(tc, inst,
+         vcc->first_free_mrf, &sampler_index);
+
+   switch (inst->opcode) {
+   case TOY_OPCODE_TGSI_TXF:
+   case TOY_OPCODE_TGSI_TXQ:
+   case TOY_OPCODE_TGSI_TXQ_LZ:
+      need_filter = false;
+      break;
+   default:
+      need_filter = true;
+      break;
+   }
+
+   toy_compiler_lower_to_send(tc, inst, false, BRW_SFID_SAMPLER);
+   inst->src[0] = tsrc(TOY_FILE_MRF, vcc->first_free_mrf, 0);
+   inst->src[1] = desc;
+
+   /* write to a temp first */
+   tmp = tc_alloc_tmp(tc);
+   dst = inst->dst;
+   inst->dst = tmp;
+
+   tc_move_inst(tc, inst);
+
+   if (need_filter) {
+      assert(sampler_index < vcc->variant->num_sampler_views);
+      swizzles[0] = vcc->variant->sampler_view_swizzles[sampler_index].r;
+      swizzles[1] = vcc->variant->sampler_view_swizzles[sampler_index].g;
+      swizzles[2] = vcc->variant->sampler_view_swizzles[sampler_index].b;
+      swizzles[3] = vcc->variant->sampler_view_swizzles[sampler_index].a;
+   }
+   else {
+      swizzles[0] = PIPE_SWIZZLE_RED;
+      swizzles[1] = PIPE_SWIZZLE_GREEN;
+      swizzles[2] = PIPE_SWIZZLE_BLUE;
+      swizzles[3] = PIPE_SWIZZLE_ALPHA;
+   }
+
+   swizzle_zero_mask = 0;
+   swizzle_one_mask = 0;
+   swizzle_normal_mask = 0;
+   for (i = 0; i < 4; i++) {
+      switch (swizzles[i]) {
+      case PIPE_SWIZZLE_ZERO:
+         swizzle_zero_mask |= 1 << i;
+         swizzles[i] = i;
+         break;
+      case PIPE_SWIZZLE_ONE:
+         swizzle_one_mask |= 1 << i;
+         swizzles[i] = i;
+         break;
+      default:
+         swizzle_normal_mask |= 1 << i;
+         break;
+      }
+   }
+
+   /* swizzle the results */
+   if (swizzle_normal_mask) {
+      tc_MOV(tc, tdst_writemask(dst, swizzle_normal_mask),
+            tsrc_swizzle(tsrc_from(tmp), swizzles[0],
+               swizzles[1], swizzles[2], swizzles[3]));
+   }
+   if (swizzle_zero_mask)
+      tc_MOV(tc, tdst_writemask(dst, swizzle_zero_mask), tsrc_imm_f(0.0f));
+   if (swizzle_one_mask)
+      tc_MOV(tc, tdst_writemask(dst, swizzle_one_mask), tsrc_imm_f(1.0f));
+}
+
+static void
+vs_lower_opcode_urb_write(struct toy_compiler *tc, struct toy_inst *inst)
+{
+   /* vs_write_vue() has set up the message registers */
+   toy_compiler_lower_to_send(tc, inst, false, BRW_SFID_URB);
+}
+
+static void
+vs_lower_virtual_opcodes(struct vs_compile_context *vcc)
+{
+   struct toy_compiler *tc = &vcc->tc;
+   struct toy_inst *inst;
+
+   tc_head(tc);
+   while ((inst = tc_next(tc)) != NULL) {
+      switch (inst->opcode) {
+      case TOY_OPCODE_TGSI_IN:
+      case TOY_OPCODE_TGSI_CONST:
+      case TOY_OPCODE_TGSI_SV:
+      case TOY_OPCODE_TGSI_IMM:
+         vs_lower_opcode_tgsi_direct(vcc, inst);
+         break;
+      case TOY_OPCODE_TGSI_INDIRECT_FETCH:
+      case TOY_OPCODE_TGSI_INDIRECT_STORE:
+         vs_lower_opcode_tgsi_indirect(vcc, inst);
+         break;
+      case TOY_OPCODE_TGSI_TEX:
+      case TOY_OPCODE_TGSI_TXB:
+      case TOY_OPCODE_TGSI_TXD:
+      case TOY_OPCODE_TGSI_TXL:
+      case TOY_OPCODE_TGSI_TXP:
+      case TOY_OPCODE_TGSI_TXF:
+      case TOY_OPCODE_TGSI_TXQ:
+      case TOY_OPCODE_TGSI_TXQ_LZ:
+      case TOY_OPCODE_TGSI_TEX2:
+      case TOY_OPCODE_TGSI_TXB2:
+      case TOY_OPCODE_TGSI_TXL2:
+      case TOY_OPCODE_TGSI_SAMPLE:
+      case TOY_OPCODE_TGSI_SAMPLE_I:
+      case TOY_OPCODE_TGSI_SAMPLE_I_MS:
+      case TOY_OPCODE_TGSI_SAMPLE_B:
+      case TOY_OPCODE_TGSI_SAMPLE_C:
+      case TOY_OPCODE_TGSI_SAMPLE_C_LZ:
+      case TOY_OPCODE_TGSI_SAMPLE_D:
+      case TOY_OPCODE_TGSI_SAMPLE_L:
+      case TOY_OPCODE_TGSI_GATHER4:
+      case TOY_OPCODE_TGSI_SVIEWINFO:
+      case TOY_OPCODE_TGSI_SAMPLE_POS:
+      case TOY_OPCODE_TGSI_SAMPLE_INFO:
+         vs_lower_opcode_tgsi_sampling(vcc, inst);
+         break;
+      case TOY_OPCODE_INV:
+      case TOY_OPCODE_LOG:
+      case TOY_OPCODE_EXP:
+      case TOY_OPCODE_SQRT:
+      case TOY_OPCODE_RSQ:
+      case TOY_OPCODE_SIN:
+      case TOY_OPCODE_COS:
+      case TOY_OPCODE_FDIV:
+      case TOY_OPCODE_POW:
+      case TOY_OPCODE_INT_DIV_QUOTIENT:
+      case TOY_OPCODE_INT_DIV_REMAINDER:
+         toy_compiler_lower_math(tc, inst);
+         break;
+      case TOY_OPCODE_URB_WRITE:
+         vs_lower_opcode_urb_write(tc, inst);
+         break;
+      default:
+         if (inst->opcode > 127)
+            tc_fail(tc, "unhandled virtual opcode");
+         break;
+      }
+   }
+}
+
+/**
+ * Compile the shader.
+ */
+static bool
+vs_compile(struct vs_compile_context *vcc)
+{
+   struct toy_compiler *tc = &vcc->tc;
+   struct ilo_shader *sh = vcc->shader;
+
+   vs_lower_virtual_opcodes(vcc);
+   toy_compiler_legalize_for_ra(tc);
+   toy_compiler_optimize(tc);
+   toy_compiler_allocate_registers(tc,
+         vcc->first_free_grf,
+         vcc->last_free_grf,
+         vcc->num_grf_per_vrf);
+   toy_compiler_legalize_for_asm(tc);
+
+   if (tc->fail) {
+      ilo_err("failed to legalize VS instructions: %s\n", tc->reason);
+      return false;
+   }
+
+   if (ilo_debug & ILO_DEBUG_VS) {
+      ilo_printf("legalized instructions:\n");
+      toy_compiler_dump(tc);
+      ilo_printf("\n");
+   }
+
+   if (true) {
+      sh->kernel = toy_compiler_assemble(tc, &sh->kernel_size);
+   }
+   else {
+      static const uint32_t microcode[] = {
+         /* fill in the microcode here */
+         0x0, 0x0, 0x0, 0x0,
+      };
+      const bool swap = true;
+
+      sh->kernel_size = sizeof(microcode);
+      sh->kernel = MALLOC(sh->kernel_size);
+
+      if (sh->kernel) {
+         const int num_dwords = sizeof(microcode) / 4;
+         const uint32_t *src = microcode;
+         uint32_t *dst = (uint32_t *) sh->kernel;
+         int i;
+
+         for (i = 0; i < num_dwords; i += 4) {
+            if (swap) {
+               dst[i + 0] = src[i + 3];
+               dst[i + 1] = src[i + 2];
+               dst[i + 2] = src[i + 1];
+               dst[i + 3] = src[i + 0];
+            }
+            else {
+               memcpy(dst, src, 16);
+            }
+         }
+      }
+   }
+
+   if (!sh->kernel) {
+      ilo_err("failed to compile VS: %s\n", tc->reason);
+      return false;
+   }
+
+   if (ilo_debug & ILO_DEBUG_VS) {
+      ilo_printf("disassembly:\n");
+      toy_compiler_disassemble(tc, sh->kernel, sh->kernel_size);
+      ilo_printf("\n");
+   }
+
+   return true;
+}
+
+/**
+ * Collect the toy registers to be written to the VUE.
+ */
+static int
+vs_collect_outputs(struct vs_compile_context *vcc, struct toy_src *outs)
+{
+   const struct toy_tgsi *tgsi = &vcc->tgsi;
+   int i;
+
+   for (i = 0; i < vcc->shader->out.count; i++) {
+      const int slot = vcc->output_map[i];
+      const int vrf = (slot >= 0) ? toy_tgsi_get_vrf(tgsi,
+            TGSI_FILE_OUTPUT, 0, tgsi->outputs[slot].index) : -1;
+      struct toy_src src;
+
+      if (vrf >= 0) {
+         struct toy_dst dst;
+
+         dst = tdst(TOY_FILE_VRF, vrf, 0);
+         src = tsrc_from(dst);
+
+         if (i == 0) {
+            /* PSIZE is at channel W */
+            tc_MOV(&vcc->tc, tdst_writemask(dst, TOY_WRITEMASK_W),
+                  tsrc_swizzle1(src, TOY_SWIZZLE_X));
+
+            /* the other channels are for the header */
+            dst = tdst_d(dst);
+            tc_MOV(&vcc->tc, tdst_writemask(dst, TOY_WRITEMASK_XYZ),
+                  tsrc_imm_d(0));
+         }
+         else {
+            /* initialize unused channels to 0.0f */
+            if (tgsi->outputs[slot].undefined_mask) {
+               dst = tdst_writemask(dst, tgsi->outputs[slot].undefined_mask);
+               tc_MOV(&vcc->tc, dst, tsrc_imm_f(0.0f));
+            }
+         }
+      }
+      else {
+         /* XXX this is too ugly */
+         if (vcc->shader->out.semantic_names[i] == TGSI_SEMANTIC_CLIPDIST &&
+             slot < 0) {
+            /* ok, we need to compute clip distance */
+            int clipvert_slot = -1, clipvert_vrf, j;
+
+            for (j = 0; j < tgsi->num_outputs; j++) {
+               if (tgsi->outputs[j].semantic_name ==
+                     TGSI_SEMANTIC_CLIPVERTEX) {
+                  clipvert_slot = j;
+                  break;
+               }
+               else if (tgsi->outputs[j].semantic_name ==
+                     TGSI_SEMANTIC_POSITION) {
+                  /* remember pos, but keep looking */
+                  clipvert_slot = j;
+               }
+            }
+
+            clipvert_vrf = (clipvert_slot >= 0) ? toy_tgsi_get_vrf(tgsi,
+                  TGSI_FILE_OUTPUT, 0, tgsi->outputs[clipvert_slot].index) : -1;
+            if (clipvert_vrf >= 0) {
+               struct toy_dst tmp = tc_alloc_tmp(&vcc->tc);
+               struct toy_src clipvert = tsrc(TOY_FILE_VRF, clipvert_vrf, 0);
+               int first_ucp, last_ucp;
+
+               if (vcc->shader->out.semantic_indices[i]) {
+                  first_ucp = 4;
+                  last_ucp = MIN2(7, vcc->variant->u.vs.num_ucps - 1);
+               }
+               else {
+                  first_ucp = 0;
+                  last_ucp = MIN2(3, vcc->variant->u.vs.num_ucps - 1);
+               }
+
+               for (j = first_ucp; j <= last_ucp; j++) {
+                  const int plane_grf = vcc->first_const_grf + j / 2;
+                  const int plane_subreg = (j & 1) * 16;
+                  const struct toy_src plane = tsrc_rect(tsrc(TOY_FILE_GRF,
+                           plane_grf, plane_subreg), TOY_RECT_041);
+                  const unsigned writemask = 1 << ((j >= 4) ? j - 4 : j);
+
+                  tc_DP4(&vcc->tc, tdst_writemask(tmp, writemask),
+                        clipvert, plane);
+               }
+
+               src = tsrc_from(tmp);
+            }
+            else {
+               src = tsrc_imm_f(0.0f);
+            }
+         }
+         else {
+            src = (i == 0) ? tsrc_imm_d(0) : tsrc_imm_f(0.0f);
+         }
+      }
+
+      outs[i] = src;
+   }
+
+   return i;
+}
+
+/**
+ * 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 = BRW_MASK_DISABLE;
+
+   if (tc->gen >= 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 = BRW_EXECUTE_1;
+      inst->access_mode = BRW_ALIGN_1;
+      inst->mask_ctrl = BRW_MASK_DISABLE;
+   }
+
+   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 (tc->gen >= 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, BRW_URB_SWIZZLE_INTERLEAVE, sent_attrs / 2, 0);
+
+      tc_add2(tc, TOY_OPCODE_URB_WRITE, tdst_null(), tsrc_from(header), desc);
+
+      sent_attrs += num_attrs;
+   }
+}
+
+/**
+ * Set up shader inputs for fixed-function units.
+ */
+static void
+vs_setup_shader_in(struct ilo_shader *sh, const struct toy_tgsi *tgsi)
+{
+   int num_attrs, i;
+
+   /* vertex/instance id is the first VE if exists */
+   for (i = 0; i < tgsi->num_system_values; i++) {
+      bool found = false;
+
+      switch (tgsi->system_values[i].semantic_name) {
+      case TGSI_SEMANTIC_INSTANCEID:
+      case TGSI_SEMANTIC_VERTEXID:
+         found = true;
+         break;
+      default:
+         break;
+      }
+
+      if (found) {
+         sh->in.semantic_names[sh->in.count] =
+            tgsi->system_values[i].semantic_name;
+         sh->in.semantic_indices[sh->in.count] =
+            tgsi->system_values[i].semantic_index;
+         sh->in.interp[sh->in.count] = TGSI_INTERPOLATE_CONSTANT;
+         sh->in.centroid[sh->in.count] = false;
+
+         sh->in.count++;
+         break;
+      }
+   }
+
+   num_attrs = 0;
+   for (i = 0; i < tgsi->num_inputs; i++) {
+      assert(tgsi->inputs[i].semantic_name == TGSI_SEMANTIC_GENERIC);
+      if (tgsi->inputs[i].semantic_index >= num_attrs)
+         num_attrs = tgsi->inputs[i].semantic_index + 1;
+   }
+   assert(num_attrs <= PIPE_MAX_ATTRIBS);
+
+   /* VF cannot remap VEs.  VE[i] must be used as GENERIC[i]. */
+   for (i = 0; i < num_attrs; i++) {
+      sh->in.semantic_names[sh->in.count + i] = TGSI_SEMANTIC_GENERIC;
+      sh->in.semantic_indices[sh->in.count + i] = i;
+      sh->in.interp[sh->in.count + i] = TGSI_INTERPOLATE_CONSTANT;
+      sh->in.centroid[sh->in.count + i] = false;
+   }
+
+   sh->in.count += num_attrs;
+
+   sh->in.has_pos = false;
+   sh->in.has_linear_interp = false;
+   sh->in.barycentric_interpolation_mode = 0;
+}
+
+/**
+ * Set up shader outputs for fixed-function units.
+ */
+static void
+vs_setup_shader_out(struct ilo_shader *sh, const struct toy_tgsi *tgsi,
+                    bool output_clipdist, int *output_map)
+{
+   int psize_slot = -1, pos_slot = -1;
+   int clipdist_slot[2] = { -1, -1 };
+   int color_slot[4] = { -1, -1, -1, -1 };
+   int num_outs, i;
+
+   /* find out the slots of outputs that need special care */
+   for (i = 0; i < tgsi->num_outputs; i++) {
+      switch (tgsi->outputs[i].semantic_name) {
+      case TGSI_SEMANTIC_PSIZE:
+         psize_slot = i;
+         break;
+      case TGSI_SEMANTIC_POSITION:
+         pos_slot = i;
+         break;
+      case TGSI_SEMANTIC_CLIPDIST:
+         if (tgsi->outputs[i].semantic_index)
+            clipdist_slot[1] = i;
+         else
+            clipdist_slot[0] = i;
+         break;
+      case TGSI_SEMANTIC_COLOR:
+         if (tgsi->outputs[i].semantic_index)
+            color_slot[2] = i;
+         else
+            color_slot[0] = i;
+         break;
+      case TGSI_SEMANTIC_BCOLOR:
+         if (tgsi->outputs[i].semantic_index)
+            color_slot[3] = i;
+         else
+            color_slot[1] = i;
+         break;
+      default:
+         break;
+      }
+   }
+
+   /* the first two VUEs are always PSIZE and POSITION */
+   num_outs = 2;
+   sh->out.semantic_names[0] = TGSI_SEMANTIC_PSIZE;
+   sh->out.semantic_indices[0] = 0;
+   sh->out.semantic_names[1] = TGSI_SEMANTIC_POSITION;
+   sh->out.semantic_indices[1] = 0;
+
+   sh->out.has_pos = true;
+   output_map[0] = psize_slot;
+   output_map[1] = pos_slot;
+
+   /* followed by optional clip distances */
+   if (output_clipdist) {
+      sh->out.semantic_names[num_outs] = TGSI_SEMANTIC_CLIPDIST;
+      sh->out.semantic_indices[num_outs] = 0;
+      output_map[num_outs++] = clipdist_slot[0];
+
+      sh->out.semantic_names[num_outs] = TGSI_SEMANTIC_CLIPDIST;
+      sh->out.semantic_indices[num_outs] = 1;
+      output_map[num_outs++] = clipdist_slot[1];
+   }
+
+   /*
+    * make BCOLOR follow COLOR so that we can make use of
+    * ATTRIBUTE_SWIZZLE_INPUTATTR_FACING in 3DSTATE_SF
+    */
+   for (i = 0; i < 4; i++) {
+      const int slot = color_slot[i];
+
+      if (slot < 0)
+         continue;
+
+      sh->out.semantic_names[num_outs] = tgsi->outputs[slot].semantic_name;
+      sh->out.semantic_indices[num_outs] = tgsi->outputs[slot].semantic_index;
+
+      output_map[num_outs++] = slot;
+   }
+
+   /* add the rest of the outputs */
+   for (i = 0; i < tgsi->num_outputs; i++) {
+      switch (tgsi->outputs[i].semantic_name) {
+      case TGSI_SEMANTIC_PSIZE:
+      case TGSI_SEMANTIC_POSITION:
+      case TGSI_SEMANTIC_CLIPDIST:
+      case TGSI_SEMANTIC_COLOR:
+      case TGSI_SEMANTIC_BCOLOR:
+         break;
+      default:
+         sh->out.semantic_names[num_outs] = tgsi->outputs[i].semantic_name;
+         sh->out.semantic_indices[num_outs] = tgsi->outputs[i].semantic_index;
+         output_map[num_outs++] = i;
+         break;
+      }
+   }
+
+   sh->out.count = num_outs;
+}
+
+/**
+ * Translate the TGSI tokens.
+ */
+static bool
+vs_setup_tgsi(struct toy_compiler *tc, const struct tgsi_token *tokens,
+              struct toy_tgsi *tgsi)
+{
+   if (ilo_debug & ILO_DEBUG_VS) {
+      ilo_printf("dumping vertex shader\n");
+      ilo_printf("\n");
+
+      tgsi_dump(tokens, 0);
+      ilo_printf("\n");
+   }
+
+   toy_compiler_translate_tgsi(tc, tokens, true, tgsi);
+   if (tc->fail) {
+      ilo_err("failed to translate VS TGSI tokens: %s\n", tc->reason);
+      return false;
+   }
+
+   if (ilo_debug & ILO_DEBUG_VS) {
+      ilo_printf("TGSI translator:\n");
+      toy_tgsi_dump(tgsi);
+      ilo_printf("\n");
+      toy_compiler_dump(tc);
+      ilo_printf("\n");
+   }
+
+   return true;
+}
+
+/**
+ * Set up VS compile context.  This includes translating the TGSI tokens.
+ */
+static bool
+vs_setup(struct vs_compile_context *vcc,
+         const struct ilo_shader_state *state,
+         const struct ilo_shader_variant *variant)
+{
+   int num_consts;
+
+   memset(vcc, 0, sizeof(*vcc));
+
+   vcc->shader = CALLOC_STRUCT(ilo_shader);
+   if (!vcc->shader)
+      return false;
+
+   vcc->variant = variant;
+
+   toy_compiler_init(&vcc->tc, state->info.gen);
+   vcc->tc.templ.access_mode = BRW_ALIGN_16;
+   vcc->tc.templ.exec_size = BRW_EXECUTE_8;
+   vcc->tc.rect_linear_width = 4;
+
+   /*
+    * The classic driver uses the sampler cache (gen6) or the data cache
+    * (gen7).  Why?
+    */
+   vcc->const_cache = GEN6_SFID_DATAPORT_CONSTANT_CACHE;
+
+   if (!vs_setup_tgsi(&vcc->tc, state->info.tokens, &vcc->tgsi)) {
+      toy_compiler_cleanup(&vcc->tc);
+      FREE(vcc->shader);
+      return false;
+   }
+
+   vs_setup_shader_in(vcc->shader, &vcc->tgsi);
+   vs_setup_shader_out(vcc->shader, &vcc->tgsi,
+         (vcc->variant->u.vs.num_ucps > 0), vcc->output_map);
+
+   /* fit each pair of user clip planes into a register */
+   num_consts = (vcc->variant->u.vs.num_ucps + 1) / 2;
+
+   /* r0 is reserved for payload header */
+   vcc->first_const_grf = 1;
+   vcc->first_vue_grf = vcc->first_const_grf + num_consts;
+   vcc->first_free_grf = vcc->first_vue_grf + vcc->shader->in.count;
+   vcc->last_free_grf = 127;
+
+   /* m0 is reserved for system routines */
+   vcc->first_free_mrf = 1;
+   vcc->last_free_mrf = 15;
+
+   vcc->num_grf_per_vrf = 1;
+
+   if (vcc->tc.gen >= ILO_GEN(7)) {
+      vcc->last_free_grf -= 15;
+      vcc->first_free_mrf = vcc->last_free_grf + 1;
+      vcc->last_free_mrf = vcc->first_free_mrf + 14;
+   }
+
+   vcc->shader->in.start_grf = vcc->first_const_grf;
+   vcc->shader->pcb.clip_state_size =
+      vcc->variant->u.vs.num_ucps * (sizeof(float) * 4);
+
+   return true;
+}
+
+/**
+ * Compile the vertex shader.
+ */
+struct ilo_shader *
+ilo_shader_compile_vs(const struct ilo_shader_state *state,
+                      const struct ilo_shader_variant *variant)
+{
+   struct vs_compile_context vcc;
+   bool need_gs;
+
+   if (!vs_setup(&vcc, state, variant))
+      return NULL;
+
+   if (vcc.tc.gen >= ILO_GEN(7)) {
+      need_gs = false;
+   }
+   else {
+      need_gs = variant->u.vs.rasterizer_discard ||
+                state->info.stream_output.num_outputs;
+   }
+
+   vs_write_vue(&vcc);
+
+   if (!vs_compile(&vcc)) {
+      FREE(vcc.shader);
+      vcc.shader = NULL;
+   }
+
+   toy_tgsi_cleanup(&vcc.tgsi);
+   toy_compiler_cleanup(&vcc.tc);
+
+   if (need_gs) {
+      int so_mapping[PIPE_MAX_SHADER_OUTPUTS];
+      int i, j;
+
+      for (i = 0; i < vcc.tgsi.num_outputs; i++) {
+         int attr = 0;
+
+         for (j = 0; j < vcc.shader->out.count; j++) {
+            if (vcc.tgsi.outputs[i].semantic_name ==
+                  vcc.shader->out.semantic_names[j] &&
+                vcc.tgsi.outputs[i].semantic_index ==
+                  vcc.shader->out.semantic_indices[j]) {
+               attr = j;
+               break;
+            }
+         }
+
+         so_mapping[i] = attr;
+      }
+
+      if (!ilo_shader_compile_gs_passthrough(state, variant,
+               so_mapping, vcc.shader)) {
+         ilo_shader_destroy(vcc.shader);
+         vcc.shader = NULL;
+      }
+   }
+
+   return vcc.shader;
+}