/*
 * Copyright 2017 Advanced Micro Devices, Inc.
 * All Rights Reserved.
 *
 * 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
 * on the rights to use, copy, modify, merge, publish, distribute, sub
 * license, 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 (including the next
 * paragraph) 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 NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHOR(S) AND/OR THEIR SUPPLIERS 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.
 */

/*
 * This is ported mostly out of radeonsi, if we can drop TGSI, we can likely
 * make a lot this go away.
 */

#include "nir_to_tgsi_info.h"
#include "util/u_math.h"
#include "util/u_prim.h"
#include "nir.h"
#include "nir_deref.h"
#include "tgsi/tgsi_scan.h"
#include "tgsi/tgsi_from_mesa.h"

static nir_variable* tex_get_texture_var(nir_tex_instr *instr)
{
   for (unsigned i = 0; i < instr->num_srcs; i++) {
      switch (instr->src[i].src_type) {
      case nir_tex_src_texture_deref:
         return nir_deref_instr_get_variable(nir_src_as_deref(instr->src[i].src));
      default:
         break;
      }
   }

   return NULL;
}

static nir_variable* intrinsic_get_var(nir_intrinsic_instr *instr)
{
   return nir_deref_instr_get_variable(nir_src_as_deref(instr->src[0]));
}


static void gather_usage_helper(const nir_deref_instr **deref_ptr,
                                unsigned location,
                                uint8_t mask,
                                uint8_t *usage_mask)
{
   for (; *deref_ptr; deref_ptr++) {
      const nir_deref_instr *deref = *deref_ptr;
      switch (deref->deref_type) {
      case nir_deref_type_array: {
         bool is_compact = nir_deref_instr_get_variable(deref)->data.compact;
         unsigned elem_size = is_compact ? DIV_ROUND_UP(glsl_get_length(deref->type), 4) :
            glsl_count_attribute_slots(deref->type, false);
         if (nir_src_is_const(deref->arr.index)) {
            if (is_compact) {
               location += nir_src_as_uint(deref->arr.index) / 4;
               mask <<= nir_src_as_uint(deref->arr.index) % 4;
            } else
               location += elem_size * nir_src_as_uint(deref->arr.index);
         } else {
            unsigned array_elems =
               glsl_get_length(deref_ptr[-1]->type);
            for (unsigned i = 0; i < array_elems; i++) {
               gather_usage_helper(deref_ptr + 1,
                                   location + elem_size * i,
                                   mask, usage_mask);
            }
            return;
         }
         break;
      }
      case nir_deref_type_struct: {
         const struct glsl_type *parent_type =
            deref_ptr[-1]->type;
         unsigned index = deref->strct.index;
         for (unsigned i = 0; i < index; i++) {
            const struct glsl_type *ft = glsl_get_struct_field(parent_type, i);
            location += glsl_count_attribute_slots(ft, false);
         }
         break;
      }
      default:
         unreachable("Unhandled deref type in gather_components_used_helper");
      }
   }

   usage_mask[location] |= mask & 0xf;
   if (mask & 0xf0)
      usage_mask[location + 1] |= (mask >> 4) & 0xf;
}

static void gather_usage(const nir_deref_instr *deref,
                         uint8_t mask,
                         uint8_t *usage_mask)
{
   nir_deref_path path;
   nir_deref_path_init(&path, (nir_deref_instr *)deref, NULL);

   unsigned location_frac = path.path[0]->var->data.location_frac;
   if (glsl_type_is_64bit(deref->type)) {
      uint8_t new_mask = 0;
      for (unsigned i = 0; i < 4; i++) {
         if (mask & (1 << i))
            new_mask |= 0x3 << (2 * i);
      }
      mask = new_mask << location_frac;
   } else {
      mask <<= location_frac;
      mask &= 0xf;
   }

   gather_usage_helper((const nir_deref_instr **)&path.path[1],
                       path.path[0]->var->data.driver_location,
                       mask, usage_mask);

   nir_deref_path_finish(&path);
}

static void gather_intrinsic_load_deref_info(const nir_shader *nir,
                                             const nir_intrinsic_instr *instr,
                                             const nir_deref_instr *deref,
                                             bool need_texcoord,
                                             nir_variable *var,
                                             struct tgsi_shader_info *info)
{
   assert(var && var->data.mode == nir_var_shader_in);

   if (nir->info.stage == MESA_SHADER_FRAGMENT)
      gather_usage(deref, nir_ssa_def_components_read(&instr->dest.ssa),
                   info->input_usage_mask);

   switch (nir->info.stage) {
   case MESA_SHADER_VERTEX: {

      break;
   }
   default: {
      unsigned semantic_name, semantic_index;
      tgsi_get_gl_varying_semantic(var->data.location, need_texcoord,
                                   &semantic_name, &semantic_index);

      if (semantic_name == TGSI_SEMANTIC_COLOR) {
         uint8_t mask = nir_ssa_def_components_read(&instr->dest.ssa);
         info->colors_read |= mask << (semantic_index * 4);
      }
      if (semantic_name == TGSI_SEMANTIC_FACE) {
         info->uses_frontface = true;
      }
      break;
   }
   }
}

static void scan_instruction(const struct nir_shader *nir,
                             bool need_texcoord,
                             struct tgsi_shader_info *info,
                             nir_instr *instr)
{
   if (instr->type == nir_instr_type_alu) {
      nir_alu_instr *alu = nir_instr_as_alu(instr);

      switch (alu->op) {
      case nir_op_fddx:
      case nir_op_fddy:
      case nir_op_fddx_fine:
      case nir_op_fddy_fine:
      case nir_op_fddx_coarse:
      case nir_op_fddy_coarse:
         info->uses_derivatives = true;
         break;
      default:
         break;
      }
   } else if (instr->type == nir_instr_type_tex) {
      nir_tex_instr *tex = nir_instr_as_tex(instr);
      nir_variable *texture = tex_get_texture_var(tex);

      if (!texture) {
         info->samplers_declared |=
            u_bit_consecutive(tex->sampler_index, 1);
      } else {
         if (texture->data.bindless)
            info->uses_bindless_samplers = true;
      }

      switch (tex->op) {
      case nir_texop_tex:
      case nir_texop_txb:
      case nir_texop_lod:
         info->uses_derivatives = true;
         break;
      default:
         break;
      }
   } else if (instr->type == nir_instr_type_intrinsic) {
      nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);

      switch (intr->intrinsic) {
      case nir_intrinsic_load_front_face:
         info->uses_frontface = 1;
         break;
      case nir_intrinsic_load_instance_id:
         info->uses_instanceid = 1;
         break;
      case nir_intrinsic_load_invocation_id:
         info->uses_invocationid = true;
         break;
      case nir_intrinsic_load_num_workgroups:
         info->uses_grid_size = true;
         break;
      case nir_intrinsic_load_workgroup_size:
         /* The block size is translated to IMM with a fixed block size. */
         if (info->properties[TGSI_PROPERTY_CS_FIXED_BLOCK_WIDTH] == 0)
            info->uses_block_size = true;
         break;
      case nir_intrinsic_load_local_invocation_id:
      case nir_intrinsic_load_workgroup_id: {
         unsigned mask = nir_ssa_def_components_read(&intr->dest.ssa);
         while (mask) {
            unsigned i = u_bit_scan(&mask);

            if (intr->intrinsic == nir_intrinsic_load_workgroup_id)
               info->uses_block_id[i] = true;
            else
               info->uses_thread_id[i] = true;
         }
         break;
      }
      case nir_intrinsic_load_vertex_id:
         info->uses_vertexid = 1;
         break;
      case nir_intrinsic_load_vertex_id_zero_base:
         info->uses_vertexid_nobase = 1;
         break;
      case nir_intrinsic_load_base_vertex:
         info->uses_basevertex = 1;
         break;
      case nir_intrinsic_load_draw_id:
         info->uses_drawid = 1;
         break;
      case nir_intrinsic_load_primitive_id:
         info->uses_primid = 1;
         break;
      case nir_intrinsic_load_sample_mask_in:
         info->reads_samplemask = true;
         break;
      case nir_intrinsic_load_tess_level_inner:
      case nir_intrinsic_load_tess_level_outer:
         info->reads_tess_factors = true;
         break;
      case nir_intrinsic_bindless_image_load:
         info->uses_bindless_images = true;

         if (nir_intrinsic_image_dim(intr) == GLSL_SAMPLER_DIM_BUF)
            info->uses_bindless_buffer_load = true;
         else
            info->uses_bindless_image_load = true;
         break;
      case nir_intrinsic_bindless_image_size:
      case nir_intrinsic_bindless_image_samples:
         info->uses_bindless_images = true;
         break;
      case nir_intrinsic_bindless_image_store:
         info->uses_bindless_images = true;

         if (nir_intrinsic_image_dim(intr) == GLSL_SAMPLER_DIM_BUF)
            info->uses_bindless_buffer_store = true;
         else
            info->uses_bindless_image_store = true;

         info->writes_memory = true;
         break;
      case nir_intrinsic_image_deref_store:
         info->writes_memory = true;
         break;
      case nir_intrinsic_bindless_image_atomic_add:
      case nir_intrinsic_bindless_image_atomic_imin:
      case nir_intrinsic_bindless_image_atomic_imax:
      case nir_intrinsic_bindless_image_atomic_umin:
      case nir_intrinsic_bindless_image_atomic_umax:
      case nir_intrinsic_bindless_image_atomic_and:
      case nir_intrinsic_bindless_image_atomic_or:
      case nir_intrinsic_bindless_image_atomic_xor:
      case nir_intrinsic_bindless_image_atomic_exchange:
      case nir_intrinsic_bindless_image_atomic_comp_swap:
         info->uses_bindless_images = true;

         if (nir_intrinsic_image_dim(intr) == GLSL_SAMPLER_DIM_BUF)
            info->uses_bindless_buffer_atomic = true;
         else
            info->uses_bindless_image_atomic = true;

         info->writes_memory = true;
         break;
      case nir_intrinsic_image_deref_atomic_add:
      case nir_intrinsic_image_deref_atomic_imin:
      case nir_intrinsic_image_deref_atomic_imax:
      case nir_intrinsic_image_deref_atomic_umin:
      case nir_intrinsic_image_deref_atomic_umax:
      case nir_intrinsic_image_deref_atomic_and:
      case nir_intrinsic_image_deref_atomic_or:
      case nir_intrinsic_image_deref_atomic_xor:
      case nir_intrinsic_image_deref_atomic_exchange:
      case nir_intrinsic_image_deref_atomic_comp_swap:
         info->writes_memory = true;
         break;
      case nir_intrinsic_store_ssbo:
      case nir_intrinsic_ssbo_atomic_add:
      case nir_intrinsic_ssbo_atomic_imin:
      case nir_intrinsic_ssbo_atomic_umin:
      case nir_intrinsic_ssbo_atomic_imax:
      case nir_intrinsic_ssbo_atomic_umax:
      case nir_intrinsic_ssbo_atomic_and:
      case nir_intrinsic_ssbo_atomic_or:
      case nir_intrinsic_ssbo_atomic_xor:
      case nir_intrinsic_ssbo_atomic_exchange:
      case nir_intrinsic_ssbo_atomic_comp_swap:
         info->writes_memory = true;
         break;
      case nir_intrinsic_load_deref: {
         nir_variable *var = intrinsic_get_var(intr);
         nir_variable_mode mode = var->data.mode;
         nir_deref_instr *const deref = nir_src_as_deref(intr->src[0]);
         enum glsl_base_type base_type =
            glsl_get_base_type(glsl_without_array(var->type));

         if (nir_deref_instr_has_indirect(deref)) {
            if (mode == nir_var_shader_in)
               info->indirect_files |= (1 << TGSI_FILE_INPUT);
         }
         if (mode == nir_var_shader_in) {
            gather_intrinsic_load_deref_info(nir, intr, deref, need_texcoord, var, info);

            switch (var->data.interpolation) {
            case INTERP_MODE_NONE:
               if (glsl_base_type_is_integer(base_type))
                  break;

               FALLTHROUGH;
            case INTERP_MODE_SMOOTH:
               if (var->data.sample)
                  info->uses_persp_sample = true;
               else if (var->data.centroid)
                  info->uses_persp_centroid = true;
               else
                  info->uses_persp_center = true;
               break;

            case INTERP_MODE_NOPERSPECTIVE:
               if (var->data.sample)
                  info->uses_linear_sample = true;
               else if (var->data.centroid)
                  info->uses_linear_centroid = true;
               else
                  info->uses_linear_center = true;
               break;
            }
         }
         break;
      }
      case nir_intrinsic_interp_deref_at_centroid:
      case nir_intrinsic_interp_deref_at_sample:
      case nir_intrinsic_interp_deref_at_offset: {
         enum glsl_interp_mode interp = intrinsic_get_var(intr)->data.interpolation;
         switch (interp) {
         case INTERP_MODE_SMOOTH:
         case INTERP_MODE_NONE:
            if (intr->intrinsic == nir_intrinsic_interp_deref_at_centroid)
               info->uses_persp_opcode_interp_centroid = true;
            else if (intr->intrinsic == nir_intrinsic_interp_deref_at_sample)
               info->uses_persp_opcode_interp_sample = true;
            else
               info->uses_persp_opcode_interp_offset = true;
            break;
         case INTERP_MODE_NOPERSPECTIVE:
            if (intr->intrinsic == nir_intrinsic_interp_deref_at_centroid)
               info->uses_linear_opcode_interp_centroid = true;
            else if (intr->intrinsic == nir_intrinsic_interp_deref_at_sample)
               info->uses_linear_opcode_interp_sample = true;
            else
               info->uses_linear_opcode_interp_offset = true;
            break;
         case INTERP_MODE_FLAT:
            break;
         default:
            unreachable("Unsupported interpoation type");
         }
         break;
      }
      default:
         break;
      }
   }
}

void nir_tgsi_scan_shader(const struct nir_shader *nir,
                          struct tgsi_shader_info *info,
                          bool need_texcoord)
{
   nir_function *func;
   unsigned i;

   info->processor = pipe_shader_type_from_mesa(nir->info.stage);
   info->num_tokens = 2; /* indicate that the shader is non-empty */
   info->num_instructions = 2;

   info->properties[TGSI_PROPERTY_NEXT_SHADER] =
      pipe_shader_type_from_mesa(nir->info.next_stage);

   if (nir->info.stage == MESA_SHADER_VERTEX) {
      info->properties[TGSI_PROPERTY_VS_WINDOW_SPACE_POSITION] =
         nir->info.vs.window_space_position;
   }

   if (nir->info.stage == MESA_SHADER_TESS_CTRL) {
      info->properties[TGSI_PROPERTY_TCS_VERTICES_OUT] =
         nir->info.tess.tcs_vertices_out;
   }

   if (nir->info.stage == MESA_SHADER_TESS_EVAL) {
      info->properties[TGSI_PROPERTY_TES_PRIM_MODE] = u_tess_prim_from_shader(nir->info.tess._primitive_mode);

      STATIC_ASSERT((TESS_SPACING_EQUAL + 1) % 3 == PIPE_TESS_SPACING_EQUAL);
      STATIC_ASSERT((TESS_SPACING_FRACTIONAL_ODD + 1) % 3 ==
                    PIPE_TESS_SPACING_FRACTIONAL_ODD);
      STATIC_ASSERT((TESS_SPACING_FRACTIONAL_EVEN + 1) % 3 ==
                    PIPE_TESS_SPACING_FRACTIONAL_EVEN);

      info->properties[TGSI_PROPERTY_TES_SPACING] = (nir->info.tess.spacing + 1) % 3;
      info->properties[TGSI_PROPERTY_TES_VERTEX_ORDER_CW] = !nir->info.tess.ccw;
      info->properties[TGSI_PROPERTY_TES_POINT_MODE] = nir->info.tess.point_mode;
   }

   if (nir->info.stage == MESA_SHADER_GEOMETRY) {
      info->properties[TGSI_PROPERTY_GS_INPUT_PRIM] = nir->info.gs.input_primitive;
      info->properties[TGSI_PROPERTY_GS_OUTPUT_PRIM] = nir->info.gs.output_primitive;
      info->properties[TGSI_PROPERTY_GS_MAX_OUTPUT_VERTICES] = nir->info.gs.vertices_out;
      info->properties[TGSI_PROPERTY_GS_INVOCATIONS] = nir->info.gs.invocations;
   }

   if (nir->info.stage == MESA_SHADER_FRAGMENT) {
      info->properties[TGSI_PROPERTY_FS_EARLY_DEPTH_STENCIL] =
         nir->info.fs.early_fragment_tests | nir->info.fs.post_depth_coverage;
      info->properties[TGSI_PROPERTY_FS_POST_DEPTH_COVERAGE] = nir->info.fs.post_depth_coverage;
      info->uses_fbfetch = nir->info.fs.uses_fbfetch_output;

      if (nir->info.fs.pixel_center_integer) {
         info->properties[TGSI_PROPERTY_FS_COORD_PIXEL_CENTER] =
            TGSI_FS_COORD_PIXEL_CENTER_INTEGER;
      }

      if (nir->info.fs.depth_layout != FRAG_DEPTH_LAYOUT_NONE) {
         switch (nir->info.fs.depth_layout) {
         case FRAG_DEPTH_LAYOUT_ANY:
            info->properties[TGSI_PROPERTY_FS_DEPTH_LAYOUT] = TGSI_FS_DEPTH_LAYOUT_ANY;
            break;
         case FRAG_DEPTH_LAYOUT_GREATER:
            info->properties[TGSI_PROPERTY_FS_DEPTH_LAYOUT] = TGSI_FS_DEPTH_LAYOUT_GREATER;
            break;
         case FRAG_DEPTH_LAYOUT_LESS:
            info->properties[TGSI_PROPERTY_FS_DEPTH_LAYOUT] = TGSI_FS_DEPTH_LAYOUT_LESS;
            break;
         case FRAG_DEPTH_LAYOUT_UNCHANGED:
            info->properties[TGSI_PROPERTY_FS_DEPTH_LAYOUT] = TGSI_FS_DEPTH_LAYOUT_UNCHANGED;
            break;
         default:
            unreachable("Unknow depth layout");
         }
      }
   }

   if (gl_shader_stage_is_compute(nir->info.stage)) {
      info->properties[TGSI_PROPERTY_CS_FIXED_BLOCK_WIDTH] = nir->info.workgroup_size[0];
      info->properties[TGSI_PROPERTY_CS_FIXED_BLOCK_HEIGHT] = nir->info.workgroup_size[1];
      info->properties[TGSI_PROPERTY_CS_FIXED_BLOCK_DEPTH] = nir->info.workgroup_size[2];
   }

   i = 0;
   uint64_t processed_inputs = 0;
   nir_foreach_shader_in_variable(variable, nir) {
      unsigned semantic_name, semantic_index;

      const struct glsl_type *type = variable->type;
      if (nir_is_arrayed_io(variable, nir->info.stage)) {
         assert(glsl_type_is_array(type));
         type = glsl_get_array_element(type);
      }

      unsigned attrib_count = variable->data.compact ? DIV_ROUND_UP(glsl_get_length(type), 4) :
         glsl_count_attribute_slots(type, nir->info.stage == MESA_SHADER_VERTEX);

      i = variable->data.driver_location;

      /* Vertex shader inputs don't have semantics. The state
       * tracker has already mapped them to attributes via
       * variable->data.driver_location.
       */
      if (nir->info.stage == MESA_SHADER_VERTEX) {
         continue;
      }

      for (unsigned j = 0; j < attrib_count; j++, i++) {

         if (processed_inputs & ((uint64_t)1 << i))
            continue;

         processed_inputs |= ((uint64_t)1 << i);

         tgsi_get_gl_varying_semantic(variable->data.location + j, need_texcoord,
                                      &semantic_name, &semantic_index);

         info->input_semantic_name[i] = semantic_name;
         info->input_semantic_index[i] = semantic_index;

         if (semantic_name == TGSI_SEMANTIC_PRIMID)
            info->uses_primid = true;

         enum glsl_base_type base_type =
            glsl_get_base_type(glsl_without_array(variable->type));

         if (variable->data.centroid)
            info->input_interpolate_loc[i] = TGSI_INTERPOLATE_LOC_CENTROID;
         if (variable->data.sample)
            info->input_interpolate_loc[i] = TGSI_INTERPOLATE_LOC_SAMPLE;

         switch (variable->data.interpolation) {
         case INTERP_MODE_NONE:
            if (glsl_base_type_is_integer(base_type)) {
               info->input_interpolate[i] = TGSI_INTERPOLATE_CONSTANT;
               break;
            }

            if (semantic_name == TGSI_SEMANTIC_COLOR) {
               info->input_interpolate[i] = TGSI_INTERPOLATE_COLOR;
               break;
            }
            FALLTHROUGH;

         case INTERP_MODE_SMOOTH:
            assert(!glsl_base_type_is_integer(base_type));

            info->input_interpolate[i] = TGSI_INTERPOLATE_PERSPECTIVE;
            break;

         case INTERP_MODE_NOPERSPECTIVE:
            assert(!glsl_base_type_is_integer(base_type));

            info->input_interpolate[i] = TGSI_INTERPOLATE_LINEAR;
            break;

         case INTERP_MODE_FLAT:
            info->input_interpolate[i] = TGSI_INTERPOLATE_CONSTANT;
            break;
         }
      }
   }

   info->num_inputs = nir->num_inputs;
   if (nir->info.io_lowered) {
      info->num_inputs = util_bitcount64(nir->info.inputs_read);
      if (nir->info.inputs_read_indirectly)
         info->indirect_files |= 1 << TGSI_FILE_INPUT;
      info->file_max[TGSI_FILE_INPUT] = info->num_inputs - 1;
   } else {
      int max = info->file_max[TGSI_FILE_INPUT] = -1;
      nir_foreach_shader_in_variable(var, nir) {
         int slots = glsl_count_attribute_slots(var->type, false);
         int tmax = var->data.driver_location + slots - 1;
         if (tmax > max)
            max = tmax;
         info->file_max[TGSI_FILE_INPUT] = max;
      }
   }

   i = 0;
   uint64_t processed_outputs = 0;
   unsigned num_outputs = 0;
   nir_foreach_shader_out_variable(variable, nir) {
      unsigned semantic_name, semantic_index;

      i = variable->data.driver_location;

      const struct glsl_type *type = variable->type;
      if (nir_is_arrayed_io(variable, nir->info.stage)) {
         assert(glsl_type_is_array(type));
         type = glsl_get_array_element(type);
      }

      unsigned attrib_count = variable->data.compact ? DIV_ROUND_UP(glsl_get_length(type), 4) :
         glsl_count_attribute_slots(type, false);
      for (unsigned k = 0; k < attrib_count; k++, i++) {

         if (nir->info.stage == MESA_SHADER_FRAGMENT) {
            tgsi_get_gl_frag_result_semantic(variable->data.location + k,
                                             &semantic_name, &semantic_index);

            /* Adjust for dual source blending */
            if (variable->data.index > 0) {
               semantic_index++;
            }
         } else {
            tgsi_get_gl_varying_semantic(variable->data.location + k, need_texcoord,
                                         &semantic_name, &semantic_index);
         }

         unsigned num_components = 4;
         unsigned vector_elements = glsl_get_vector_elements(glsl_without_array(variable->type));
         if (vector_elements)
            num_components = vector_elements;

         unsigned component = variable->data.location_frac;
         if (glsl_type_is_64bit(glsl_without_array(variable->type))) {
            if (glsl_type_is_dual_slot(glsl_without_array(variable->type)) && k % 2) {
               num_components = (num_components * 2) - 4;
               component = 0;
            } else {
               num_components = MIN2(num_components * 2, 4);
            }
         }

         ubyte usagemask = 0;
         for (unsigned j = component; j < num_components + component; j++) {
            switch (j) {
            case 0:
               usagemask |= TGSI_WRITEMASK_X;
               break;
            case 1:
               usagemask |= TGSI_WRITEMASK_Y;
               break;
            case 2:
               usagemask |= TGSI_WRITEMASK_Z;
               break;
            case 3:
               usagemask |= TGSI_WRITEMASK_W;
               break;
            default:
               unreachable("error calculating component index");
            }
         }

         unsigned gs_out_streams;
         if (variable->data.stream & NIR_STREAM_PACKED) {
            gs_out_streams = variable->data.stream & ~NIR_STREAM_PACKED;
         } else {
            assert(variable->data.stream < 4);
            gs_out_streams = 0;
            for (unsigned j = 0; j < num_components; ++j)
               gs_out_streams |= variable->data.stream << (2 * (component + j));
         }

         unsigned streamx = gs_out_streams & 3;
         unsigned streamy = (gs_out_streams >> 2) & 3;
         unsigned streamz = (gs_out_streams >> 4) & 3;
         unsigned streamw = (gs_out_streams >> 6) & 3;

         if (usagemask & TGSI_WRITEMASK_X) {
            info->output_usagemask[i] |= TGSI_WRITEMASK_X;
            info->output_streams[i] |= streamx;
            info->num_stream_output_components[streamx]++;
         }
         if (usagemask & TGSI_WRITEMASK_Y) {
            info->output_usagemask[i] |= TGSI_WRITEMASK_Y;
            info->output_streams[i] |= streamy << 2;
            info->num_stream_output_components[streamy]++;
         }
         if (usagemask & TGSI_WRITEMASK_Z) {
            info->output_usagemask[i] |= TGSI_WRITEMASK_Z;
            info->output_streams[i] |= streamz << 4;
            info->num_stream_output_components[streamz]++;
         }
         if (usagemask & TGSI_WRITEMASK_W) {
            info->output_usagemask[i] |= TGSI_WRITEMASK_W;
            info->output_streams[i] |= streamw << 6;
            info->num_stream_output_components[streamw]++;
         }

         /* make sure we only count this location once against
          * the num_outputs counter.
          */
         if (processed_outputs & ((uint64_t)1 << i))
            continue;

         processed_outputs |= ((uint64_t)1 << i);
         num_outputs++;

         info->output_semantic_name[i] = semantic_name;
         info->output_semantic_index[i] = semantic_index;

         switch (semantic_name) {
         case TGSI_SEMANTIC_PRIMID:
            info->writes_primid = true;
            break;
         case TGSI_SEMANTIC_VIEWPORT_INDEX:
            info->writes_viewport_index = true;
            break;
         case TGSI_SEMANTIC_LAYER:
            info->writes_layer = true;
            break;
         case TGSI_SEMANTIC_PSIZE:
            info->writes_psize = true;
            break;
         case TGSI_SEMANTIC_CLIPVERTEX:
            info->writes_clipvertex = true;
            break;
         case TGSI_SEMANTIC_COLOR:
            info->colors_written |= 1 << semantic_index;
            break;
         case TGSI_SEMANTIC_STENCIL:
            info->writes_stencil = true;
            break;
         case TGSI_SEMANTIC_SAMPLEMASK:
            info->writes_samplemask = true;
            break;
         case TGSI_SEMANTIC_EDGEFLAG:
            info->writes_edgeflag = true;
            break;
         case TGSI_SEMANTIC_POSITION:
            if (info->processor == PIPE_SHADER_FRAGMENT)
               info->writes_z = true;
            else
               info->writes_position = true;
            break;
         }

         if (nir->info.stage == MESA_SHADER_TESS_CTRL) {
            switch (semantic_name) {
            case TGSI_SEMANTIC_PATCH:
               info->reads_perpatch_outputs = true;
               break;
            case TGSI_SEMANTIC_TESSINNER:
            case TGSI_SEMANTIC_TESSOUTER:
               info->reads_tessfactor_outputs = true;
               break;
            default:
               info->reads_pervertex_outputs = true;
            }
         }
      }

      unsigned loc = variable->data.location;
      if (nir->info.stage == MESA_SHADER_FRAGMENT &&
          loc == FRAG_RESULT_COLOR &&
          nir->info.outputs_written & (1ull << loc)) {
         assert(attrib_count == 1);
         info->properties[TGSI_PROPERTY_FS_COLOR0_WRITES_ALL_CBUFS] = true;
      }
   }

   if (nir->info.io_lowered) {
      uint64_t outputs_written = nir->info.outputs_written;

      while (outputs_written) {
         unsigned location = u_bit_scan64(&outputs_written);
         unsigned i = util_bitcount64(nir->info.outputs_written &
                                      BITFIELD64_MASK(location));
         unsigned semantic_name, semantic_index;

         tgsi_get_gl_varying_semantic(location, need_texcoord,
                                      &semantic_name, &semantic_index);

         info->output_semantic_name[i] = semantic_name;
         info->output_semantic_index[i] = semantic_index;
         info->output_usagemask[i] = 0xf;
      }
      num_outputs = util_bitcount64(nir->info.outputs_written);
      if (nir->info.outputs_accessed_indirectly)
         info->indirect_files |= 1 << TGSI_FILE_OUTPUT;
   }

   uint32_t sampler_mask = 0;
   nir_foreach_uniform_variable(var, nir) {
      uint32_t sampler_count = glsl_type_get_sampler_count(var->type) +
                               glsl_type_get_texture_count(var->type);
      sampler_mask |= ((1ull << sampler_count) - 1) << var->data.binding;
   }
   uint32_t image_mask = 0;
   nir_foreach_image_variable(var, nir) {
      uint32_t image_count = glsl_type_get_image_count(var->type);
      image_mask |= ((1ull << image_count) - 1) << var->data.binding;
   }
   info->num_outputs = num_outputs;

   info->const_file_max[0] = nir->num_uniforms - 1;
   info->const_buffers_declared = u_bit_consecutive(1, nir->info.num_ubos);
   if (nir->num_uniforms > 0)
      info->const_buffers_declared |= 1;
   info->images_declared = image_mask;
   info->samplers_declared = sampler_mask;

   info->file_max[TGSI_FILE_SAMPLER] = util_last_bit(info->samplers_declared) - 1;
   info->file_max[TGSI_FILE_SAMPLER_VIEW] = BITSET_LAST_BIT(nir->info.textures_used) - 1;
   info->file_mask[TGSI_FILE_SAMPLER] = info->samplers_declared;
   info->file_mask[TGSI_FILE_SAMPLER_VIEW] = nir->info.textures_used[0];
   info->file_max[TGSI_FILE_IMAGE] = util_last_bit(info->images_declared) - 1;
   info->file_mask[TGSI_FILE_IMAGE] = info->images_declared;

   info->num_written_clipdistance = nir->info.clip_distance_array_size;
   info->num_written_culldistance = nir->info.cull_distance_array_size;
   info->clipdist_writemask = u_bit_consecutive(0, info->num_written_clipdistance);
   info->culldist_writemask = u_bit_consecutive(0, info->num_written_culldistance);

   if (info->processor == PIPE_SHADER_FRAGMENT)
      info->uses_kill = nir->info.fs.uses_discard;

   func = (struct nir_function *)exec_list_get_head_const(&nir->functions);
   nir_foreach_block(block, func->impl) {
      nir_foreach_instr(instr, block)
         scan_instruction(nir, need_texcoord, info, instr);
   }
}
