vbo/dlist: realloc vertex stores

[platform/upstream/mesa.git] / src / mesa / vbo / vbo_save_api.c

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/*
 * Authors:
 *   Keith Whitwell <keithw@vmware.com>
 */



/* Display list compiler attempts to store lists of vertices with the
 * same vertex layout.  Additionally it attempts to minimize the need
 * for execute-time fixup of these vertex lists, allowing them to be
 * cached on hardware.
 *
 * There are still some circumstances where this can be thwarted, for
 * example by building a list that consists of one very long primitive
 * (eg Begin(Triangles), 1000 vertices, End), and calling that list
 * from inside a different begin/end object (Begin(Lines), CallList,
 * End).
 *
 * In that case the code will have to replay the list as individual
 * commands through the Exec dispatch table, or fix up the copied
 * vertices at execute-time.
 *
 * The other case where fixup is required is when a vertex attribute
 * is introduced in the middle of a primitive.  Eg:
 *  Begin(Lines)
 *  TexCoord1f()           Vertex2f()
 *  TexCoord1f() Color3f() Vertex2f()
 *  End()
 *
 *  If the current value of Color isn't known at compile-time, this
 *  primitive will require fixup.
 *
 *
 * The list compiler currently doesn't attempt to compile lists
 * containing EvalCoord or EvalPoint commands.  On encountering one of
 * these, compilation falls back to opcodes.
 *
 * This could be improved to fallback only when a mix of EvalCoord and
 * Vertex commands are issued within a single primitive.
 */


#include "main/glheader.h"
#include "main/arrayobj.h"
#include "main/bufferobj.h"
#include "main/context.h"
#include "main/dlist.h"
#include "main/enums.h"
#include "main/eval.h"
#include "main/macros.h"
#include "main/draw_validate.h"
#include "main/api_arrayelt.h"
#include "main/vtxfmt.h"
#include "main/dispatch.h"
#include "main/state.h"
#include "main/varray.h"
#include "util/bitscan.h"
#include "util/u_memory.h"
#include "util/hash_table.h"

#include "gallium/include/pipe/p_state.h"

#include "vbo_noop.h"
#include "vbo_private.h"


#ifdef ERROR
#undef ERROR
#endif

/* An interesting VBO number/name to help with debugging */
#define VBO_BUF_ID  12345

static void GLAPIENTRY
_save_Materialfv(GLenum face, GLenum pname, const GLfloat *params);

static void GLAPIENTRY
_save_EvalCoord1f(GLfloat u);

static void GLAPIENTRY
_save_EvalCoord2f(GLfloat u, GLfloat v);

/*
 * NOTE: Old 'parity' issue is gone, but copying can still be
 * wrong-footed on replay.
 */
static GLuint
copy_vertices(struct gl_context *ctx,
              const struct vbo_save_vertex_list *node,
              const fi_type * src_buffer)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   struct _mesa_prim *prim = &node->cold->prims[node->cold->prim_count - 1];
   GLuint sz = save->vertex_size;
   const fi_type *src = src_buffer + prim->start * sz;
   fi_type *dst = save->copied.buffer;

   if (prim->end)
      return 0;

   return vbo_copy_vertices(ctx, prim->mode, prim->start, &prim->count,
                            prim->begin, sz, true, dst, src);
}


static struct vbo_save_vertex_store *
realloc_vertex_store(struct vbo_save_vertex_store *store, uint32_t vertex_size, int vertex_count)
{
   if (!store)
      store = CALLOC_STRUCT(vbo_save_vertex_store);

   int new_size = MAX2(vertex_count * vertex_size, VBO_SAVE_BUFFER_SIZE) * sizeof(GLfloat);
   if (new_size > store->buffer_in_ram_size) {
      store->buffer_in_ram_size = new_size;
      store->buffer_in_ram = realloc(store->buffer_in_ram, store->buffer_in_ram_size);
   }

   return store;
}


static struct vbo_save_primitive_store *
realloc_prim_store(struct vbo_save_primitive_store *store, int prim_count)
{
   if (store == NULL)
      store = CALLOC_STRUCT(vbo_save_primitive_store);
   uint32_t old_size = store->size;
   store->size = MAX3(store->size, prim_count, VBO_SAVE_PRIM_SIZE);
   store->prims = realloc(store->prims, store->size * sizeof(struct _mesa_prim));
   memset(&store->prims[old_size], 0, (store->size - old_size) * sizeof(struct _mesa_prim));
   store->used = 0;
   return store;
}


static void
reset_counters(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;

   save->vertex_store->used = 0;

   if (save->vertex_size)
      save->max_vert = save->vertex_store->buffer_in_ram_size / (sizeof(float) * save->vertex_size);
   else
      save->max_vert = 0;

   save->prim_store->used = 0;
   save->vert_count = 0;
   save->dangling_attr_ref = GL_FALSE;
}

/**
 * For a list of prims, try merging prims that can just be extensions of the
 * previous prim.
 */
static void
merge_prims(struct gl_context *ctx, struct _mesa_prim *prim_list,
            GLuint *prim_count)
{
   GLuint i;
   struct _mesa_prim *prev_prim = prim_list;

   for (i = 1; i < *prim_count; i++) {
      struct _mesa_prim *this_prim = prim_list + i;

      vbo_try_prim_conversion(&this_prim->mode, &this_prim->count);

      if (vbo_merge_draws(ctx, true,
                          prev_prim->mode, this_prim->mode,
                          prev_prim->start, this_prim->start,
                          &prev_prim->count, this_prim->count,
                          prev_prim->basevertex, this_prim->basevertex,
                          &prev_prim->end,
                          this_prim->begin, this_prim->end)) {
         /* We've found a prim that just extend the previous one.  Tack it
          * onto the previous one, and let this primitive struct get dropped.
          */
         continue;
      }

      /* If any previous primitives have been dropped, then we need to copy
       * this later one into the next available slot.
       */
      prev_prim++;
      if (prev_prim != this_prim)
         *prev_prim = *this_prim;
   }

   *prim_count = prev_prim - prim_list + 1;
}


/**
 * Convert GL_LINE_LOOP primitive into GL_LINE_STRIP so that drivers
 * don't have to worry about handling the _mesa_prim::begin/end flags.
 * See https://bugs.freedesktop.org/show_bug.cgi?id=81174
 */
static void
convert_line_loop_to_strip(struct vbo_save_context *save,
                           struct vbo_save_vertex_list *node)
{
   struct _mesa_prim *prim = &node->cold->prims[node->cold->prim_count - 1];

   assert(prim->mode == GL_LINE_LOOP);

   if (prim->end) {
      /* Copy the 0th vertex to end of the buffer and extend the
       * vertex count by one to finish the line loop.
       */
      const GLuint sz = save->vertex_size;
      /* 0th vertex: */
      const fi_type *src = save->vertex_store->buffer_in_ram + prim->start * sz;
      /* end of buffer: */
      fi_type *dst = save->vertex_store->buffer_in_ram + (prim->start + prim->count) * sz;

      memcpy(dst, src, sz * sizeof(float));

      prim->count++;
      node->cold->vertex_count++;
      save->vert_count++;
      save->vertex_store->used += sz;
   }

   if (!prim->begin) {
      /* Drawing the second or later section of a long line loop.
       * Skip the 0th vertex.
       */
      prim->start++;
      prim->count--;
   }

   prim->mode = GL_LINE_STRIP;
}


/* Compare the present vao if it has the same setup. */
static bool
compare_vao(gl_vertex_processing_mode mode,
            const struct gl_vertex_array_object *vao,
            const struct gl_buffer_object *bo, GLintptr buffer_offset,
            GLuint stride, GLbitfield64 vao_enabled,
            const GLubyte size[VBO_ATTRIB_MAX],
            const GLenum16 type[VBO_ATTRIB_MAX],
            const GLuint offset[VBO_ATTRIB_MAX])
{
   if (!vao)
      return false;

   /* If the enabled arrays are not the same we are not equal. */
   if (vao_enabled != vao->Enabled)
      return false;

   /* Check the buffer binding at 0 */
   if (vao->BufferBinding[0].BufferObj != bo)
      return false;
   /* BufferBinding[0].Offset != buffer_offset is checked per attribute */
   if (vao->BufferBinding[0].Stride != stride)
      return false;
   assert(vao->BufferBinding[0].InstanceDivisor == 0);

   /* Retrieve the mapping from VBO_ATTRIB to VERT_ATTRIB space */
   const GLubyte *const vao_to_vbo_map = _vbo_attribute_alias_map[mode];

   /* Now check the enabled arrays */
   GLbitfield mask = vao_enabled;
   while (mask) {
      const int attr = u_bit_scan(&mask);
      const unsigned char vbo_attr = vao_to_vbo_map[attr];
      const GLenum16 tp = type[vbo_attr];
      const GLintptr off = offset[vbo_attr] + buffer_offset;
      const struct gl_array_attributes *attrib = &vao->VertexAttrib[attr];
      if (attrib->RelativeOffset + vao->BufferBinding[0].Offset != off)
         return false;
      if (attrib->Format.Type != tp)
         return false;
      if (attrib->Format.Size != size[vbo_attr])
         return false;
      assert(attrib->Format.Format == GL_RGBA);
      assert(attrib->Format.Normalized == GL_FALSE);
      assert(attrib->Format.Integer == vbo_attrtype_to_integer_flag(tp));
      assert(attrib->Format.Doubles == vbo_attrtype_to_double_flag(tp));
      assert(attrib->BufferBindingIndex == 0);
   }

   return true;
}


/* Create or reuse the vao for the vertex processing mode. */
static void
update_vao(struct gl_context *ctx,
           gl_vertex_processing_mode mode,
           struct gl_vertex_array_object **vao,
           struct gl_buffer_object *bo, GLintptr buffer_offset,
           GLuint stride, GLbitfield64 vbo_enabled,
           const GLubyte size[VBO_ATTRIB_MAX],
           const GLenum16 type[VBO_ATTRIB_MAX],
           const GLuint offset[VBO_ATTRIB_MAX])
{
   /* Compute the bitmasks of vao_enabled arrays */
   GLbitfield vao_enabled = _vbo_get_vao_enabled_from_vbo(mode, vbo_enabled);

   /*
    * Check if we can possibly reuse the exisiting one.
    * In the long term we should reset them when something changes.
    */
   if (compare_vao(mode, *vao, bo, buffer_offset, stride,
                   vao_enabled, size, type, offset))
      return;

   /* The initial refcount is 1 */
   _mesa_reference_vao(ctx, vao, NULL);
   *vao = _mesa_new_vao(ctx, ~((GLuint)0));

   /*
    * assert(stride <= ctx->Const.MaxVertexAttribStride);
    * MaxVertexAttribStride is not set for drivers that does not
    * expose GL 44 or GLES 31.
    */

   /* Bind the buffer object at binding point 0 */
   _mesa_bind_vertex_buffer(ctx, *vao, 0, bo, buffer_offset, stride, false,
                            false);

   /* Retrieve the mapping from VBO_ATTRIB to VERT_ATTRIB space
    * Note that the position/generic0 aliasing is done in the VAO.
    */
   const GLubyte *const vao_to_vbo_map = _vbo_attribute_alias_map[mode];
   /* Now set the enable arrays */
   GLbitfield mask = vao_enabled;
   while (mask) {
      const int vao_attr = u_bit_scan(&mask);
      const GLubyte vbo_attr = vao_to_vbo_map[vao_attr];
      assert(offset[vbo_attr] <= ctx->Const.MaxVertexAttribRelativeOffset);

      _vbo_set_attrib_format(ctx, *vao, vao_attr, buffer_offset,
                             size[vbo_attr], type[vbo_attr], offset[vbo_attr]);
      _mesa_vertex_attrib_binding(ctx, *vao, vao_attr, 0);
   }
   _mesa_enable_vertex_array_attribs(ctx, *vao, vao_enabled);
   assert(vao_enabled == (*vao)->Enabled);
   assert((vao_enabled & ~(*vao)->VertexAttribBufferMask) == 0);

   /* Finalize and freeze the VAO */
   _mesa_set_vao_immutable(ctx, *vao);
}


static void
realloc_storage(struct gl_context *ctx, int prim_count, int vertex_count)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   if (vertex_count >= 0)
      save->vertex_store = realloc_vertex_store(save->vertex_store, save->vertex_size, vertex_count);

   if (prim_count >= 0)
      save->prim_store = realloc_prim_store(save->prim_store, prim_count);
}

struct vertex_key {
   unsigned vertex_size;
   fi_type *vertex_attributes;
};

static uint32_t _hash_vertex_key(const void *key)
{
   struct vertex_key *k = (struct vertex_key*)key;
   unsigned sz = k->vertex_size;
   assert(sz);
   return _mesa_hash_data(k->vertex_attributes, sz * sizeof(float));
}

static bool _compare_vertex_key(const void *key1, const void *key2)
{
   struct vertex_key *k1 = (struct vertex_key*)key1;
   struct vertex_key *k2 = (struct vertex_key*)key2;
   /* All the compared vertices are going to be drawn with the same VAO,
    * so we can compare the attributes. */
   assert (k1->vertex_size == k2->vertex_size);
   return memcmp(k1->vertex_attributes,
                 k2->vertex_attributes,
                 k1->vertex_size * sizeof(float)) == 0;
}

static void _free_entry(struct hash_entry *entry)
{
   free((void*)entry->key);
}

/* Add vertex to the vertex buffer and return its index. If this vertex is a duplicate
 * of an existing vertex, return the original index instead.
 */
static uint32_t
add_vertex(struct vbo_save_context *save, struct hash_table *hash_to_index,
           uint32_t index, fi_type *new_buffer, uint32_t *max_index)
{
   /* If vertex deduplication is disabled return the original index. */
   if (!hash_to_index)
      return index;

   fi_type *vert = save->vertex_store->buffer_in_ram + save->vertex_size * index;

   struct vertex_key *key = malloc(sizeof(struct vertex_key));
   key->vertex_size = save->vertex_size;
   key->vertex_attributes = vert;

   struct hash_entry *entry = _mesa_hash_table_search(hash_to_index, key);
   if (entry) {
      free(key);
      /* We found an existing vertex with the same hash, return its index. */
      return (uintptr_t) entry->data;
   } else {
      /* This is a new vertex. Determine a new index and copy its attributes to the vertex
       * buffer. Note that 'new_buffer' is created at each list compilation so we write vertices
       * starting at index 0.
       */
      uint32_t n = _mesa_hash_table_num_entries(hash_to_index);
      *max_index = MAX2(n, *max_index);

      memcpy(&new_buffer[save->vertex_size * n],
             vert,
             save->vertex_size * sizeof(fi_type));

      _mesa_hash_table_insert(hash_to_index, key, (void*)(uintptr_t)(n));

      /* The index buffer is shared between list compilations, so add the base index to get
       * the final index.
       */
      return n;
   }
}


/**
 * Insert the active immediate struct onto the display list currently
 * being built.
 */
static void
compile_vertex_list(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   struct vbo_save_vertex_list *node;

   /* Allocate space for this structure in the display list currently
    * being compiled.
    */
   node = (struct vbo_save_vertex_list *)
      _mesa_dlist_alloc_vertex_list(ctx, !save->dangling_attr_ref && !save->no_current_update);

   if (!node)
      return;

   memset(node, 0, sizeof(struct vbo_save_vertex_list));
   node->cold = calloc(1, sizeof(*node->cold));

   /* Make sure the pointer is aligned to the size of a pointer */
   assert((GLintptr) node % sizeof(void *) == 0);

   const GLsizei stride = save->vertex_size*sizeof(GLfloat);

   node->cold->vertex_count = save->vert_count;
   node->cold->wrap_count = save->copied.nr;
   node->cold->prims = malloc(sizeof(struct _mesa_prim) * save->prim_store->used);
   memcpy(node->cold->prims, save->prim_store->prims, sizeof(struct _mesa_prim) * save->prim_store->used);
   node->cold->ib.obj = NULL;
   node->cold->prim_count = save->prim_store->used;

   if (save->no_current_update) {
      node->cold->current_data = NULL;
   }
   else {
      GLuint current_size = save->vertex_size - save->attrsz[0];
      node->cold->current_data = NULL;

      if (current_size) {
         node->cold->current_data = malloc(current_size * sizeof(GLfloat));
         if (node->cold->current_data) {
            const char *buffer = (const char *)save->vertex_store->buffer_in_ram;
            unsigned attr_offset = save->attrsz[0] * sizeof(GLfloat);
            unsigned vertex_offset = 0;

            if (node->cold->vertex_count)
               vertex_offset = (node->cold->vertex_count - 1) * stride;

            memcpy(node->cold->current_data, buffer + vertex_offset + attr_offset,
                   current_size * sizeof(GLfloat));
         } else {
            _mesa_error(ctx, GL_OUT_OF_MEMORY, "Current value allocation");
         }
      }
   }

   assert(save->attrsz[VBO_ATTRIB_POS] != 0 || node->cold->vertex_count == 0);

   if (save->dangling_attr_ref)
      ctx->ListState.Current.UseLoopback = true;

   /* Copy duplicated vertices
    */
   save->copied.nr = copy_vertices(ctx, node, save->vertex_store->buffer_in_ram);

   if (node->cold->prims[node->cold->prim_count - 1].mode == GL_LINE_LOOP) {
      convert_line_loop_to_strip(save, node);
   }

   merge_prims(ctx, node->cold->prims, &node->cold->prim_count);

   GLintptr buffer_offset = 0;
   GLuint start_offset = 0;

   /* Create an index buffer. */
   node->cold->min_index = node->cold->max_index = 0;
   if (save->vert_count == 0 || node->cold->prim_count == 0)
      goto end;

   /* We won't modify node->prims, so use a const alias to avoid unintended
    * writes to it. */
   const struct _mesa_prim *original_prims = node->cold->prims;

   int end = original_prims[node->cold->prim_count - 1].start +
             original_prims[node->cold->prim_count - 1].count;
   int total_vert_count = end - original_prims[0].start;

   node->cold->min_index = node->cold->prims[0].start;
   node->cold->max_index = end - 1;

   /* Estimate for the worst case: all prims are line strips (the +1 is because
    * wrap_buffers may call use but the last primitive may not be complete) */
   int max_indices_count = MAX2(total_vert_count * 2 - (node->cold->prim_count * 2) + 1,
                                total_vert_count);

   int size = max_indices_count * sizeof(uint32_t);
   uint32_t* indices = (uint32_t*) malloc(size);
   struct _mesa_prim *merged_prims = NULL;

   int idx = 0;
   struct hash_table *vertex_to_index = NULL;
   fi_type *temp_vertices_buffer = NULL;

   /* The loopback replay code doesn't use the index buffer, so we can't
    * dedup vertices in this case.
    */
   if (!ctx->ListState.Current.UseLoopback) {
      vertex_to_index = _mesa_hash_table_create(NULL, _hash_vertex_key, _compare_vertex_key);
      temp_vertices_buffer = malloc(save->vertex_store->buffer_in_ram_size);
   }

   uint32_t max_index = 0;

   int last_valid_prim = -1;
   /* Construct indices array. */
   for (unsigned i = 0; i < node->cold->prim_count; i++) {
      assert(original_prims[i].basevertex == 0);
      GLubyte mode = original_prims[i].mode;

      int vertex_count = original_prims[i].count;
      if (!vertex_count) {
         continue;
      }

      /* Line strips may get converted to lines */
      if (mode == GL_LINE_STRIP)
         mode = GL_LINES;

      /* If 2 consecutive prims use the same mode => merge them. */
      bool merge_prims = last_valid_prim >= 0 &&
                         mode == merged_prims[last_valid_prim].mode &&
                         mode != GL_LINE_LOOP && mode != GL_TRIANGLE_FAN &&
                         mode != GL_QUAD_STRIP && mode != GL_POLYGON &&
                         mode != GL_PATCHES;

      /* To be able to merge consecutive triangle strips we need to insert
       * a degenerate triangle.
       */
      if (merge_prims &&
          mode == GL_TRIANGLE_STRIP) {
         /* Insert a degenerate triangle */
         assert(merged_prims[last_valid_prim].mode == GL_TRIANGLE_STRIP);
         unsigned tri_count = merged_prims[last_valid_prim].count - 2;

         indices[idx] = indices[idx - 1];
         indices[idx + 1] = add_vertex(save, vertex_to_index, original_prims[i].start,
                                       temp_vertices_buffer, &max_index);
         idx += 2;
         merged_prims[last_valid_prim].count += 2;

         if (tri_count % 2) {
            /* Add another index to preserve winding order */
            indices[idx++] = add_vertex(save, vertex_to_index, original_prims[i].start,
                                        temp_vertices_buffer, &max_index);
            merged_prims[last_valid_prim].count++;
         }
      }

      int start = idx;

      /* Convert line strips to lines if it'll allow if the previous
       * prim mode is GL_LINES (so merge_prims is true) or if the next
       * primitive mode is GL_LINES or GL_LINE_LOOP.
       */
      if (original_prims[i].mode == GL_LINE_STRIP &&
          (merge_prims ||
           (i < node->cold->prim_count - 1 &&
            (original_prims[i + 1].mode == GL_LINE_STRIP ||
             original_prims[i + 1].mode == GL_LINES)))) {
         for (unsigned j = 0; j < vertex_count; j++) {
            indices[idx++] = add_vertex(save, vertex_to_index, original_prims[i].start + j,
                                        temp_vertices_buffer, &max_index);
            /* Repeat all but the first/last indices. */
            if (j && j != vertex_count - 1) {
               indices[idx++] = add_vertex(save, vertex_to_index, original_prims[i].start + j,
                                           temp_vertices_buffer, &max_index);
            }
         }
      } else {
         /* We didn't convert to LINES, so restore the original mode */
         mode = original_prims[i].mode;

         for (unsigned j = 0; j < vertex_count; j++) {
            indices[idx++] = add_vertex(save, vertex_to_index, original_prims[i].start + j,
                                        temp_vertices_buffer, &max_index);
         }
      }

      if (merge_prims) {
         /* Update vertex count. */
         merged_prims[last_valid_prim].count += idx - start;
      } else {
         /* Keep this primitive */
         last_valid_prim += 1;
         assert(last_valid_prim <= i);
         merged_prims = realloc(merged_prims, (1 + last_valid_prim) * sizeof(struct _mesa_prim));
         merged_prims[last_valid_prim] = original_prims[i];
         merged_prims[last_valid_prim].start = start;
         merged_prims[last_valid_prim].count = idx - start;
      }
      merged_prims[last_valid_prim].mode = mode;
   }

   assert(idx > 0 && idx <= max_indices_count);

   unsigned merged_prim_count = last_valid_prim + 1;
   node->cold->ib.ptr = NULL;
   node->cold->ib.count = idx;
   node->cold->ib.index_size_shift = (GL_UNSIGNED_INT - GL_UNSIGNED_BYTE) >> 1;

   /* How many bytes do we need to store the indices and the vertices */
   total_vert_count = vertex_to_index ? (max_index + 1) : idx;
   unsigned total_bytes_needed = idx * sizeof(uint32_t) +
                                 total_vert_count * save->vertex_size * sizeof(fi_type);

   const GLintptr old_offset = save->VAO[0] ?
      save->VAO[0]->BufferBinding[0].Offset + save->VAO[0]->VertexAttrib[VERT_ATTRIB_POS].RelativeOffset : 0;
   if (old_offset != save->current_bo_bytes_used && stride > 0) {
      GLintptr offset_diff = save->current_bo_bytes_used - old_offset;
      while (offset_diff > 0 &&
             save->current_bo_bytes_used < save->current_bo->Size &&
             offset_diff % stride != 0) {
         save->current_bo_bytes_used++;
         offset_diff = save->current_bo_bytes_used - old_offset;
      }
   }
   buffer_offset = save->current_bo_bytes_used;

   /* Can we reuse the previous bo or should we allocate a new one? */
   int available_bytes = save->current_bo ? save->current_bo->Size - save->current_bo_bytes_used : 0;
   if (total_bytes_needed > available_bytes) {
      if (save->current_bo)
         _mesa_reference_buffer_object(ctx, &save->current_bo, NULL);
      save->current_bo = ctx->Driver.NewBufferObject(ctx, VBO_BUF_ID + 1);
      bool success = ctx->Driver.BufferData(ctx,
                                            GL_ELEMENT_ARRAY_BUFFER_ARB,
                                            MAX2(total_bytes_needed, VBO_SAVE_BUFFER_SIZE * sizeof(uint32_t)),
                                            NULL,
                                            GL_STATIC_DRAW_ARB, GL_MAP_WRITE_BIT,
                                            save->current_bo);
      if (!success) {
         _mesa_reference_buffer_object(ctx, &save->current_bo, NULL);
         _mesa_error(ctx, GL_OUT_OF_MEMORY, "IB allocation");
      } else {
         save->current_bo_bytes_used = 0;
         available_bytes = save->current_bo->Size;
      }
      buffer_offset = 0;
   } else {
      assert(old_offset <= buffer_offset);
      const GLintptr offset_diff = buffer_offset - old_offset;
      if (offset_diff > 0 && stride > 0 && offset_diff % stride == 0) {
         /* The vertex size is an exact multiple of the buffer offset.
          * This means that we can use zero-based vertex attribute pointers
          * and specify the start of the primitive with the _mesa_prim::start
          * field.  This results in issuing several draw calls with identical
          * vertex attribute information.  This can result in fewer state
          * changes in drivers.  In particular, the Gallium CSO module will
          * filter out redundant vertex buffer changes.
          */
         /* We cannot immediately update the primitives as some methods below
          * still need the uncorrected start vertices
          */
         start_offset = offset_diff/stride;
         assert(old_offset == buffer_offset - offset_diff);
         buffer_offset = old_offset;
      }

      /* Correct the primitive starts, we can only do this here as copy_vertices
       * and convert_line_loop_to_strip above consume the uncorrected starts.
       * On the other hand the _vbo_loopback_vertex_list call below needs the
       * primitives to be corrected already.
       */
      for (unsigned i = 0; i < node->cold->prim_count; i++) {
         node->cold->prims[i].start += start_offset;
      }
      /* start_offset shifts vertices (so v[0] becomes v[start_offset]), so we have
       * to apply this transformation to all indices and max_index.
       */
      for (unsigned i = 0; i < idx; i++)
         indices[i] += start_offset;
      max_index += start_offset;
   }

   _mesa_reference_buffer_object(ctx, &node->cold->ib.obj, save->current_bo);

   /* Upload the vertices first (see buffer_offset) */
   ctx->Driver.BufferSubData(ctx,
                             save->current_bo_bytes_used,
                             total_vert_count * save->vertex_size * sizeof(fi_type),
                             vertex_to_index ? temp_vertices_buffer : save->vertex_store->buffer_in_ram,
                             node->cold->ib.obj);
   save->current_bo_bytes_used += total_vert_count * save->vertex_size * sizeof(fi_type);

  if (vertex_to_index) {
      _mesa_hash_table_destroy(vertex_to_index, _free_entry);
      free(temp_vertices_buffer);
   }

   /* Since we're append the indices to an existing buffer, we need to adjust the start value of each
    * primitive (not the indices themselves). */
   save->current_bo_bytes_used += align(save->current_bo_bytes_used, 4) - save->current_bo_bytes_used;
   int indices_offset = save->current_bo_bytes_used / 4;
   for (int i = 0; i < merged_prim_count; i++) {
      merged_prims[i].start += indices_offset;
   }

   /* Then upload the indices. */
   if (node->cold->ib.obj) {
      ctx->Driver.BufferSubData(ctx,
                                save->current_bo_bytes_used,
                                idx * sizeof(uint32_t),
                                indices,
                                node->cold->ib.obj);
      save->current_bo_bytes_used += idx * sizeof(uint32_t);
   } else {
      node->cold->vertex_count = 0;
      node->cold->prim_count = 0;
   }

   /* Prepare for DrawGallium */
   memset(&node->merged.info, 0, sizeof(struct pipe_draw_info));
   /* The other info fields will be updated in vbo_save_playback_vertex_list */
   node->merged.info.index_size = 4;
   node->merged.info.instance_count = 1;
   node->merged.info.index.gl_bo = node->cold->ib.obj;
   if (merged_prim_count == 1) {
      node->merged.info.mode = merged_prims[0].mode;
      node->merged.start_count.start = merged_prims[0].start;
      node->merged.start_count.count = merged_prims[0].count;
      node->merged.start_count.index_bias = 0;
      node->merged.mode = NULL;
   } else {
      node->merged.mode = malloc(merged_prim_count * sizeof(unsigned char));
      node->merged.start_counts = malloc(merged_prim_count * sizeof(struct pipe_draw_start_count_bias));
      for (unsigned i = 0; i < merged_prim_count; i++) {
         node->merged.start_counts[i].start = merged_prims[i].start;
         node->merged.start_counts[i].count = merged_prims[i].count;
         node->merged.start_counts[i].index_bias = 0;
         node->merged.mode[i] = merged_prims[i].mode;
      }
   }
   node->merged.num_draws = merged_prim_count;
   if (node->merged.num_draws > 1) {
      bool same_mode = true;
      for (unsigned i = 1; i < node->merged.num_draws && same_mode; i++) {
         same_mode = node->merged.mode[i] == node->merged.mode[0];
      }
      if (same_mode) {
         /* All primitives use the same mode, so we can simplify a bit */
         node->merged.info.mode = node->merged.mode[0];
         free(node->merged.mode);
         node->merged.mode = NULL;
      }
   }

   free(indices);
   free(merged_prims);

end:

   if (!save->current_bo) {
      save->current_bo = ctx->Driver.NewBufferObject(ctx, VBO_BUF_ID + 1);
      bool success = ctx->Driver.BufferData(ctx,
                                            GL_ELEMENT_ARRAY_BUFFER_ARB,
                                            VBO_SAVE_BUFFER_SIZE * sizeof(uint32_t),
                                            NULL,
                                            GL_STATIC_DRAW_ARB, GL_MAP_WRITE_BIT,
                                            save->current_bo);
   }

   GLuint offsets[VBO_ATTRIB_MAX];
   for (unsigned i = 0, offset = 0; i < VBO_ATTRIB_MAX; ++i) {
      offsets[i] = offset;
      offset += save->attrsz[i] * sizeof(GLfloat);
   }
   /* Create a pair of VAOs for the possible VERTEX_PROCESSING_MODEs
    * Note that this may reuse the previous one of possible.
    */
   for (gl_vertex_processing_mode vpm = VP_MODE_FF; vpm < VP_MODE_MAX; ++vpm) {
      /* create or reuse the vao */
      update_vao(ctx, vpm, &save->VAO[vpm],
                 save->current_bo, buffer_offset, stride,
                 save->enabled, save->attrsz, save->attrtype, offsets);
      /* Reference the vao in the dlist */
      node->VAO[vpm] = NULL;
      _mesa_reference_vao(ctx, &node->VAO[vpm], save->VAO[vpm]);
   }


   /* Deal with GL_COMPILE_AND_EXECUTE:
    */
   if (ctx->ExecuteFlag) {
      struct _glapi_table *dispatch = GET_DISPATCH();

      _glapi_set_dispatch(ctx->Exec);

      /* _vbo_loopback_vertex_list doesn't use the index buffer, so we have to
       * use buffer_in_ram instead of current_bo which contains all vertices instead
       * of the deduplicated vertices only in the !UseLoopback case.
       *
       * The problem is that the VAO offset is based on current_bo's layout,
       * so we have to use a temp value.
       */
      struct gl_vertex_array_object *vao = node->VAO[VP_MODE_SHADER];
      GLintptr original = vao->BufferBinding[0].Offset;
      if (!ctx->ListState.Current.UseLoopback) {
         GLintptr new_offset = 0;
         /* 'start_offset' has been added to all primitives 'start', so undo it here. */
         new_offset -= start_offset * stride;
         vao->BufferBinding[0].Offset = new_offset;
      }
      _vbo_loopback_vertex_list(ctx, node, save->vertex_store->buffer_in_ram);
      vao->BufferBinding[0].Offset = original;

      _glapi_set_dispatch(dispatch);
   }

   /* Decide whether the storage structs are full, or can be used for
    * the next vertex lists as well.
    */
   if (save->vertex_store->used >
       save->vertex_store->buffer_in_ram_size / sizeof(float) - 16 * (save->vertex_size + 4)) {
      realloc_storage(ctx, -1, 0);
   }

   /* Reset our structures for the next run of vertices:
    */
   reset_counters(ctx);
}


/**
 * This is called when we fill a vertex buffer before we hit a glEnd().
 * We
 * TODO -- If no new vertices have been stored, don't bother saving it.
 */
static void
wrap_buffers(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   GLint i = save->prim_store->used - 1;
   GLenum mode;

   assert(i < (GLint) save->prim_store->size);
   assert(i >= 0);

   /* Close off in-progress primitive.
    */
   save->prim_store->prims[i].count = (save->vert_count - save->prim_store->prims[i].start);
   mode = save->prim_store->prims[i].mode;

   /* store the copied vertices, and allocate a new list.
    */
   compile_vertex_list(ctx);

   /* Restart interrupted primitive
    */
   save->prim_store->prims[0].mode = mode;
   save->prim_store->prims[0].begin = 0;
   save->prim_store->prims[0].end = 0;
   save->prim_store->prims[0].start = 0;
   save->prim_store->prims[0].count = 0;
   save->prim_store->used = 1;
}


/**
 * Called only when buffers are wrapped as the result of filling the
 * vertex_store struct.
 */
static void
wrap_filled_vertex(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   unsigned numComponents;

   /* Emit a glEnd to close off the last vertex list.
    */
   wrap_buffers(ctx);

   /* Copy stored stored vertices to start of new list.
    */
   assert(save->max_vert - save->vert_count > save->copied.nr);

   numComponents = save->copied.nr * save->vertex_size;

   fi_type *buffer_ptr = save->vertex_store->buffer_in_ram;
   memcpy(buffer_ptr,
          save->copied.buffer,
          numComponents * sizeof(fi_type));
   assert(save->vertex_store->used == 0 && save->vert_count == 0);
   save->vert_count = save->copied.nr;
   save->vertex_store->used = numComponents;
}


static void
copy_to_current(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   GLbitfield64 enabled = save->enabled & (~BITFIELD64_BIT(VBO_ATTRIB_POS));

   while (enabled) {
      const int i = u_bit_scan64(&enabled);
      assert(save->attrsz[i]);

      if (save->attrtype[i] == GL_DOUBLE ||
          save->attrtype[i] == GL_UNSIGNED_INT64_ARB)
         memcpy(save->current[i], save->attrptr[i], save->attrsz[i] * sizeof(GLfloat));
      else
         COPY_CLEAN_4V_TYPE_AS_UNION(save->current[i], save->attrsz[i],
                                     save->attrptr[i], save->attrtype[i]);
   }
}


static void
copy_from_current(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   GLbitfield64 enabled = save->enabled & (~BITFIELD64_BIT(VBO_ATTRIB_POS));

   while (enabled) {
      const int i = u_bit_scan64(&enabled);

      switch (save->attrsz[i]) {
      case 4:
         save->attrptr[i][3] = save->current[i][3];
         FALLTHROUGH;
      case 3:
         save->attrptr[i][2] = save->current[i][2];
         FALLTHROUGH;
      case 2:
         save->attrptr[i][1] = save->current[i][1];
         FALLTHROUGH;
      case 1:
         save->attrptr[i][0] = save->current[i][0];
         break;
      case 0:
         unreachable("Unexpected vertex attribute size");
      }
   }
}


/**
 * Called when we increase the size of a vertex attribute.  For example,
 * if we've seen one or more glTexCoord2f() calls and now we get a
 * glTexCoord3f() call.
 * Flush existing data, set new attrib size, replay copied vertices.
 */
static void
upgrade_vertex(struct gl_context *ctx, GLuint attr, GLuint newsz)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   GLuint oldsz;
   GLuint i;
   fi_type *tmp;

   /* Store the current run of vertices, and emit a GL_END.  Emit a
    * BEGIN in the new buffer.
    */
   if (save->vert_count)
      wrap_buffers(ctx);
   else
      assert(save->copied.nr == 0);

   /* Do a COPY_TO_CURRENT to ensure back-copying works for the case
    * when the attribute already exists in the vertex and is having
    * its size increased.
    */
   copy_to_current(ctx);

   /* Fix up sizes:
    */
   oldsz = save->attrsz[attr];
   save->attrsz[attr] = newsz;
   save->enabled |= BITFIELD64_BIT(attr);

   save->vertex_size += newsz - oldsz;
   save->max_vert = ((save->vertex_store->buffer_in_ram_size / sizeof(float) -
                      save->vertex_store->used) /
                     save->vertex_size);
   save->vert_count = 0;

   /* Recalculate all the attrptr[] values:
    */
   tmp = save->vertex;
   for (i = 0; i < VBO_ATTRIB_MAX; i++) {
      if (save->attrsz[i]) {
         save->attrptr[i] = tmp;
         tmp += save->attrsz[i];
      }
      else {
         save->attrptr[i] = NULL;       /* will not be dereferenced. */
      }
   }

   /* Copy from current to repopulate the vertex with correct values.
    */
   copy_from_current(ctx);

   /* Replay stored vertices to translate them to new format here.
    *
    * If there are copied vertices and the new (upgraded) attribute
    * has not been defined before, this list is somewhat degenerate,
    * and will need fixup at runtime.
    */
   if (save->copied.nr) {
      const fi_type *data = save->copied.buffer;
      fi_type *dest = save->vertex_store->buffer_in_ram;

      /* Need to note this and fix up at runtime (or loopback):
       */
      if (attr != VBO_ATTRIB_POS && save->currentsz[attr][0] == 0) {
         assert(oldsz == 0);
         save->dangling_attr_ref = GL_TRUE;
      }

      for (i = 0; i < save->copied.nr; i++) {
         GLbitfield64 enabled = save->enabled;
         while (enabled) {
            const int j = u_bit_scan64(&enabled);
            assert(save->attrsz[j]);
            if (j == attr) {
               if (oldsz) {
                  COPY_CLEAN_4V_TYPE_AS_UNION(dest, oldsz, data,
                                              save->attrtype[j]);
                  data += oldsz;
                  dest += newsz;
               }
               else {
                  COPY_SZ_4V(dest, newsz, save->current[attr]);
                  dest += newsz;
               }
            }
            else {
               GLint sz = save->attrsz[j];
               COPY_SZ_4V(dest, sz, data);
               data += sz;
               dest += sz;
            }
         }
      }

      save->vert_count += save->copied.nr;
      save->vertex_store->used += save->vertex_size * save->copied.nr;
   }
}


/**
 * This is called when the size of a vertex attribute changes.
 * For example, after seeing one or more glTexCoord2f() calls we
 * get a glTexCoord4f() or glTexCoord1f() call.
 */
static void
fixup_vertex(struct gl_context *ctx, GLuint attr,
             GLuint sz, GLenum newType)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;

   if (sz > save->attrsz[attr] ||
       newType != save->attrtype[attr]) {
      /* New size is larger.  Need to flush existing vertices and get
       * an enlarged vertex format.
       */
      upgrade_vertex(ctx, attr, sz);
   }
   else if (sz < save->active_sz[attr]) {
      GLuint i;
      const fi_type *id = vbo_get_default_vals_as_union(save->attrtype[attr]);

      /* New size is equal or smaller - just need to fill in some
       * zeros.
       */
      for (i = sz; i <= save->attrsz[attr]; i++)
         save->attrptr[attr][i - 1] = id[i - 1];
   }

   save->active_sz[attr] = sz;
}


/**
 * Reset the current size of all vertex attributes to the default
 * value of 0.  This signals that we haven't yet seen any per-vertex
 * commands such as glNormal3f() or glTexCoord2f().
 */
static void
reset_vertex(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;

   while (save->enabled) {
      const int i = u_bit_scan64(&save->enabled);
      assert(save->attrsz[i]);
      save->attrsz[i] = 0;
      save->active_sz[i] = 0;
   }

   save->vertex_size = 0;
}


/**
 * If index=0, does glVertexAttrib*() alias glVertex() to emit a vertex?
 * It depends on a few things, including whether we're inside or outside
 * of glBegin/glEnd.
 */
static inline bool
is_vertex_position(const struct gl_context *ctx, GLuint index)
{
   return (index == 0 &&
           _mesa_attr_zero_aliases_vertex(ctx) &&
           _mesa_inside_dlist_begin_end(ctx));
}



#define ERROR(err)   _mesa_compile_error(ctx, err, __func__);


/* Only one size for each attribute may be active at once.  Eg. if
 * Color3f is installed/active, then Color4f may not be, even if the
 * vertex actually contains 4 color coordinates.  This is because the
 * 3f version won't otherwise set color[3] to 1.0 -- this is the job
 * of the chooser function when switching between Color4f and Color3f.
 */
#define ATTR_UNION(A, N, T, C, V0, V1, V2, V3)                  \
do {                                                            \
   struct vbo_save_context *save = &vbo_context(ctx)->save;     \
   int sz = (sizeof(C) / sizeof(GLfloat));                      \
                                                                \
   if (save->active_sz[A] != N)                                 \
      fixup_vertex(ctx, A, N * sz, T);                          \
                                                                \
   {                                                            \
      C *dest = (C *)save->attrptr[A];                          \
      if (N>0) dest[0] = V0;                                    \
      if (N>1) dest[1] = V1;                                    \
      if (N>2) dest[2] = V2;                                    \
      if (N>3) dest[3] = V3;                                    \
      save->attrtype[A] = T;                                    \
   }                                                            \
                                                                \
   if ((A) == 0) {                                              \
      GLuint i;                                                 \
      fi_type *buffer_ptr = save->vertex_store->buffer_in_ram + save->vertex_store->used; \
                                                                \
      for (i = 0; i < save->vertex_size; i++)                   \
             buffer_ptr[i] = save->vertex[i];                   \
                                                                \
      save->vertex_store->used += save->vertex_size; \
      if (++save->vert_count >= save->max_vert)                 \
         wrap_filled_vertex(ctx);                               \
   }                                                            \
} while (0)

#define TAG(x) _save_##x

#include "vbo_attrib_tmp.h"



#define MAT( ATTR, N, face, params )                    \
do {                                                    \
   if (face != GL_BACK)                                 \
      MAT_ATTR( ATTR, N, params ); /* front */          \
   if (face != GL_FRONT)                                \
      MAT_ATTR( ATTR + 1, N, params ); /* back */       \
} while (0)


/**
 * Save a glMaterial call found between glBegin/End.
 * glMaterial calls outside Begin/End are handled in dlist.c.
 */
static void GLAPIENTRY
_save_Materialfv(GLenum face, GLenum pname, const GLfloat *params)
{
   GET_CURRENT_CONTEXT(ctx);

   if (face != GL_FRONT && face != GL_BACK && face != GL_FRONT_AND_BACK) {
      _mesa_compile_error(ctx, GL_INVALID_ENUM, "glMaterial(face)");
      return;
   }

   switch (pname) {
   case GL_EMISSION:
      MAT(VBO_ATTRIB_MAT_FRONT_EMISSION, 4, face, params);
      break;
   case GL_AMBIENT:
      MAT(VBO_ATTRIB_MAT_FRONT_AMBIENT, 4, face, params);
      break;
   case GL_DIFFUSE:
      MAT(VBO_ATTRIB_MAT_FRONT_DIFFUSE, 4, face, params);
      break;
   case GL_SPECULAR:
      MAT(VBO_ATTRIB_MAT_FRONT_SPECULAR, 4, face, params);
      break;
   case GL_SHININESS:
      if (*params < 0 || *params > ctx->Const.MaxShininess) {
         _mesa_compile_error(ctx, GL_INVALID_VALUE, "glMaterial(shininess)");
      }
      else {
         MAT(VBO_ATTRIB_MAT_FRONT_SHININESS, 1, face, params);
      }
      break;
   case GL_COLOR_INDEXES:
      MAT(VBO_ATTRIB_MAT_FRONT_INDEXES, 3, face, params);
      break;
   case GL_AMBIENT_AND_DIFFUSE:
      MAT(VBO_ATTRIB_MAT_FRONT_AMBIENT, 4, face, params);
      MAT(VBO_ATTRIB_MAT_FRONT_DIFFUSE, 4, face, params);
      break;
   default:
      _mesa_compile_error(ctx, GL_INVALID_ENUM, "glMaterial(pname)");
      return;
   }
}


/* Cope with EvalCoord/CallList called within a begin/end object:
 *     -- Flush current buffer
 *     -- Fallback to opcodes for the rest of the begin/end object.
 */
static void
dlist_fallback(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;

   if (save->vert_count || save->prim_store->used) {
      if (save->prim_store->used > 0) {
         /* Close off in-progress primitive. */
         GLint i = save->prim_store->used - 1;
         save->prim_store->prims[i].count = save->vert_count - save->prim_store->prims[i].start;
      }

      /* Need to replay this display list with loopback,
       * unfortunately, otherwise this primitive won't be handled
       * properly:
       */
      save->dangling_attr_ref = GL_TRUE;

      compile_vertex_list(ctx);
   }

   copy_to_current(ctx);
   reset_vertex(ctx);
   if (save->out_of_memory) {
      _mesa_install_save_vtxfmt(ctx, &save->vtxfmt_noop);
   }
   else {
      _mesa_install_save_vtxfmt(ctx, &ctx->ListState.ListVtxfmt);
   }
   ctx->Driver.SaveNeedFlush = GL_FALSE;
}


static void GLAPIENTRY
_save_EvalCoord1f(GLfloat u)
{
   GET_CURRENT_CONTEXT(ctx);
   dlist_fallback(ctx);
   CALL_EvalCoord1f(ctx->Save, (u));
}

static void GLAPIENTRY
_save_EvalCoord1fv(const GLfloat * v)
{
   GET_CURRENT_CONTEXT(ctx);
   dlist_fallback(ctx);
   CALL_EvalCoord1fv(ctx->Save, (v));
}

static void GLAPIENTRY
_save_EvalCoord2f(GLfloat u, GLfloat v)
{
   GET_CURRENT_CONTEXT(ctx);
   dlist_fallback(ctx);
   CALL_EvalCoord2f(ctx->Save, (u, v));
}

static void GLAPIENTRY
_save_EvalCoord2fv(const GLfloat * v)
{
   GET_CURRENT_CONTEXT(ctx);
   dlist_fallback(ctx);
   CALL_EvalCoord2fv(ctx->Save, (v));
}

static void GLAPIENTRY
_save_EvalPoint1(GLint i)
{
   GET_CURRENT_CONTEXT(ctx);
   dlist_fallback(ctx);
   CALL_EvalPoint1(ctx->Save, (i));
}

static void GLAPIENTRY
_save_EvalPoint2(GLint i, GLint j)
{
   GET_CURRENT_CONTEXT(ctx);
   dlist_fallback(ctx);
   CALL_EvalPoint2(ctx->Save, (i, j));
}

static void GLAPIENTRY
_save_CallList(GLuint l)
{
   GET_CURRENT_CONTEXT(ctx);
   dlist_fallback(ctx);
   CALL_CallList(ctx->Save, (l));
}

static void GLAPIENTRY
_save_CallLists(GLsizei n, GLenum type, const GLvoid * v)
{
   GET_CURRENT_CONTEXT(ctx);
   dlist_fallback(ctx);
   CALL_CallLists(ctx->Save, (n, type, v));
}



/**
 * Called when a glBegin is getting compiled into a display list.
 * Updating of ctx->Driver.CurrentSavePrimitive is already taken care of.
 */
void
vbo_save_NotifyBegin(struct gl_context *ctx, GLenum mode,
                     bool no_current_update)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   const GLuint i = save->prim_store->used++;

   ctx->Driver.CurrentSavePrimitive = mode;

   assert(i < save->prim_store->size);
   save->prim_store->prims[i].mode = mode & VBO_SAVE_PRIM_MODE_MASK;
   save->prim_store->prims[i].begin = 1;
   save->prim_store->prims[i].end = 0;
   save->prim_store->prims[i].start = save->vert_count;
   save->prim_store->prims[i].count = 0;

   save->no_current_update = no_current_update;

   if (save->out_of_memory) {
      _mesa_install_save_vtxfmt(ctx, &save->vtxfmt_noop);
   }
   else {
      _mesa_install_save_vtxfmt(ctx, &save->vtxfmt);
   }

   /* We need to call vbo_save_SaveFlushVertices() if there's state change */
   ctx->Driver.SaveNeedFlush = GL_TRUE;
}


static void GLAPIENTRY
_save_End(void)
{
   GET_CURRENT_CONTEXT(ctx);
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   const GLint i = save->prim_store->used - 1;

   ctx->Driver.CurrentSavePrimitive = PRIM_OUTSIDE_BEGIN_END;
   save->prim_store->prims[i].end = 1;
   save->prim_store->prims[i].count = (save->vert_count - save->prim_store->prims[i].start);

   if (i == (GLint) save->prim_store->size - 1) {
      compile_vertex_list(ctx);
      assert(save->copied.nr == 0);
   }

   /* Swap out this vertex format while outside begin/end.  Any color,
    * etc. received between here and the next begin will be compiled
    * as opcodes.
    */
   if (save->out_of_memory) {
      _mesa_install_save_vtxfmt(ctx, &save->vtxfmt_noop);
   }
   else {
      _mesa_install_save_vtxfmt(ctx, &ctx->ListState.ListVtxfmt);
   }
}


static void GLAPIENTRY
_save_Begin(GLenum mode)
{
   GET_CURRENT_CONTEXT(ctx);
   (void) mode;
   _mesa_compile_error(ctx, GL_INVALID_OPERATION, "Recursive glBegin");
}


static void GLAPIENTRY
_save_PrimitiveRestartNV(void)
{
   GET_CURRENT_CONTEXT(ctx);
   struct vbo_save_context *save = &vbo_context(ctx)->save;

   if (save->prim_store->used == 0) {
      /* We're not inside a glBegin/End pair, so calling glPrimitiverRestartNV
       * is an error.
       */
      _mesa_compile_error(ctx, GL_INVALID_OPERATION,
                          "glPrimitiveRestartNV called outside glBegin/End");
   } else {
      /* get current primitive mode */
      GLenum curPrim = save->prim_store->prims[save->prim_store->used - 1].mode;
      bool no_current_update = save->no_current_update;

      /* restart primitive */
      CALL_End(ctx->CurrentServerDispatch, ());
      vbo_save_NotifyBegin(ctx, curPrim, no_current_update);
   }
}


/* Unlike the functions above, these are to be hooked into the vtxfmt
 * maintained in ctx->ListState, active when the list is known or
 * suspected to be outside any begin/end primitive.
 * Note: OBE = Outside Begin/End
 */
static void GLAPIENTRY
_save_OBE_Rectf(GLfloat x1, GLfloat y1, GLfloat x2, GLfloat y2)
{
   GET_CURRENT_CONTEXT(ctx);
   struct _glapi_table *dispatch = ctx->CurrentServerDispatch;

   vbo_save_NotifyBegin(ctx, GL_QUADS, false);
   CALL_Vertex2f(dispatch, (x1, y1));
   CALL_Vertex2f(dispatch, (x2, y1));
   CALL_Vertex2f(dispatch, (x2, y2));
   CALL_Vertex2f(dispatch, (x1, y2));
   CALL_End(dispatch, ());
}


static void GLAPIENTRY
_save_OBE_Rectd(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2)
{
   _save_OBE_Rectf((GLfloat) x1, (GLfloat) y1, (GLfloat) x2, (GLfloat) y2);
}

static void GLAPIENTRY
_save_OBE_Rectdv(const GLdouble *v1, const GLdouble *v2)
{
   _save_OBE_Rectf((GLfloat) v1[0], (GLfloat) v1[1], (GLfloat) v2[0], (GLfloat) v2[1]);
}

static void GLAPIENTRY
_save_OBE_Rectfv(const GLfloat *v1, const GLfloat *v2)
{
   _save_OBE_Rectf(v1[0], v1[1], v2[0], v2[1]);
}

static void GLAPIENTRY
_save_OBE_Recti(GLint x1, GLint y1, GLint x2, GLint y2)
{
   _save_OBE_Rectf((GLfloat) x1, (GLfloat) y1, (GLfloat) x2, (GLfloat) y2);
}

static void GLAPIENTRY
_save_OBE_Rectiv(const GLint *v1, const GLint *v2)
{
   _save_OBE_Rectf((GLfloat) v1[0], (GLfloat) v1[1], (GLfloat) v2[0], (GLfloat) v2[1]);
}

static void GLAPIENTRY
_save_OBE_Rects(GLshort x1, GLshort y1, GLshort x2, GLshort y2)
{
   _save_OBE_Rectf((GLfloat) x1, (GLfloat) y1, (GLfloat) x2, (GLfloat) y2);
}

static void GLAPIENTRY
_save_OBE_Rectsv(const GLshort *v1, const GLshort *v2)
{
   _save_OBE_Rectf((GLfloat) v1[0], (GLfloat) v1[1], (GLfloat) v2[0], (GLfloat) v2[1]);
}

static void
_ensure_draws_fits_in_storage(struct gl_context *ctx, int primcount, int vertcount)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;

   bool realloc_prim = save->prim_store->used + primcount > save->prim_store->size;
   bool realloc_vert = save->vertex_size && (save->vert_count + vertcount >= save->max_vert);

   if (realloc_prim || realloc_vert) {
      if (realloc_vert && (save->vert_count || save->prim_store->used)) {
         /* TODO: this really isn't needed. We should realloc only the CPU-side memory. */
         compile_vertex_list(ctx);
      }
      realloc_storage(ctx, realloc_prim ? primcount : -1, realloc_vert ? vertcount : -1);
   }
}


static void GLAPIENTRY
_save_OBE_DrawArrays(GLenum mode, GLint start, GLsizei count)
{
   GET_CURRENT_CONTEXT(ctx);
   struct gl_vertex_array_object *vao = ctx->Array.VAO;
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   GLint i;

   if (!_mesa_is_valid_prim_mode(ctx, mode)) {
      _mesa_compile_error(ctx, GL_INVALID_ENUM, "glDrawArrays(mode)");
      return;
   }
   if (count < 0) {
      _mesa_compile_error(ctx, GL_INVALID_VALUE, "glDrawArrays(count<0)");
      return;
   }

   if (save->out_of_memory)
      return;

   _ensure_draws_fits_in_storage(ctx, 1, count);

   /* Make sure to process any VBO binding changes */
   _mesa_update_state(ctx);

   _mesa_vao_map_arrays(ctx, vao, GL_MAP_READ_BIT);

   vbo_save_NotifyBegin(ctx, mode, true);

   for (i = 0; i < count; i++)
      _mesa_array_element(ctx, start + i);
   CALL_End(ctx->CurrentServerDispatch, ());

   _mesa_vao_unmap_arrays(ctx, vao);
}


static void GLAPIENTRY
_save_OBE_MultiDrawArrays(GLenum mode, const GLint *first,
                          const GLsizei *count, GLsizei primcount)
{
   GET_CURRENT_CONTEXT(ctx);
   GLint i;

   if (!_mesa_is_valid_prim_mode(ctx, mode)) {
      _mesa_compile_error(ctx, GL_INVALID_ENUM, "glMultiDrawArrays(mode)");
      return;
   }

   if (primcount < 0) {
      _mesa_compile_error(ctx, GL_INVALID_VALUE,
                          "glMultiDrawArrays(primcount<0)");
      return;
   }

   unsigned vertcount = 0;
   for (i = 0; i < primcount; i++) {
      if (count[i] < 0) {
         _mesa_compile_error(ctx, GL_INVALID_VALUE,
                             "glMultiDrawArrays(count[i]<0)");
         return;
      }
      vertcount += count[i];
   }

   _ensure_draws_fits_in_storage(ctx, primcount, vertcount);

   for (i = 0; i < primcount; i++) {
      if (count[i] > 0) {
         _save_OBE_DrawArrays(mode, first[i], count[i]);
      }
   }
}


static void
array_element(struct gl_context *ctx,
              GLint basevertex, GLuint elt, unsigned index_size_shift)
{
   /* Section 10.3.5 Primitive Restart:
    * [...]
    *    When one of the *BaseVertex drawing commands specified in section 10.5
    * is used, the primitive restart comparison occurs before the basevertex
    * offset is added to the array index.
    */
   /* If PrimitiveRestart is enabled and the index is the RestartIndex
    * then we call PrimitiveRestartNV and return.
    */
   if (ctx->Array._PrimitiveRestart[index_size_shift] &&
       elt == ctx->Array._RestartIndex[index_size_shift]) {
      CALL_PrimitiveRestartNV(ctx->CurrentServerDispatch, ());
      return;
   }

   _mesa_array_element(ctx, basevertex + elt);
}


/* Could do better by copying the arrays and element list intact and
 * then emitting an indexed prim at runtime.
 */
static void GLAPIENTRY
_save_OBE_DrawElementsBaseVertex(GLenum mode, GLsizei count, GLenum type,
                                 const GLvoid * indices, GLint basevertex)
{
   GET_CURRENT_CONTEXT(ctx);
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   struct gl_vertex_array_object *vao = ctx->Array.VAO;
   struct gl_buffer_object *indexbuf = vao->IndexBufferObj;
   GLint i;

   if (!_mesa_is_valid_prim_mode(ctx, mode)) {
      _mesa_compile_error(ctx, GL_INVALID_ENUM, "glDrawElements(mode)");
      return;
   }
   if (count < 0) {
      _mesa_compile_error(ctx, GL_INVALID_VALUE, "glDrawElements(count<0)");
      return;
   }
   if (type != GL_UNSIGNED_BYTE &&
       type != GL_UNSIGNED_SHORT &&
       type != GL_UNSIGNED_INT) {
      _mesa_compile_error(ctx, GL_INVALID_VALUE, "glDrawElements(count<0)");
      return;
   }

   if (save->out_of_memory)
      return;

   _ensure_draws_fits_in_storage(ctx, 1, count);

   /* Make sure to process any VBO binding changes */
   _mesa_update_state(ctx);

   _mesa_vao_map(ctx, vao, GL_MAP_READ_BIT);

   if (indexbuf)
      indices =
         ADD_POINTERS(indexbuf->Mappings[MAP_INTERNAL].Pointer, indices);

   vbo_save_NotifyBegin(ctx, mode, true);

   switch (type) {
   case GL_UNSIGNED_BYTE:
      for (i = 0; i < count; i++)
         array_element(ctx, basevertex, ((GLubyte *) indices)[i], 0);
      break;
   case GL_UNSIGNED_SHORT:
      for (i = 0; i < count; i++)
         array_element(ctx, basevertex, ((GLushort *) indices)[i], 1);
      break;
   case GL_UNSIGNED_INT:
      for (i = 0; i < count; i++)
         array_element(ctx, basevertex, ((GLuint *) indices)[i], 2);
      break;
   default:
      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawElements(type)");
      break;
   }

   CALL_End(ctx->CurrentServerDispatch, ());

   _mesa_vao_unmap(ctx, vao);
}

static void GLAPIENTRY
_save_OBE_DrawElements(GLenum mode, GLsizei count, GLenum type,
                       const GLvoid * indices)
{
   _save_OBE_DrawElementsBaseVertex(mode, count, type, indices, 0);
}


static void GLAPIENTRY
_save_OBE_DrawRangeElements(GLenum mode, GLuint start, GLuint end,
                            GLsizei count, GLenum type,
                            const GLvoid * indices)
{
   GET_CURRENT_CONTEXT(ctx);
   struct vbo_save_context *save = &vbo_context(ctx)->save;

   if (!_mesa_is_valid_prim_mode(ctx, mode)) {
      _mesa_compile_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(mode)");
      return;
   }
   if (count < 0) {
      _mesa_compile_error(ctx, GL_INVALID_VALUE,
                          "glDrawRangeElements(count<0)");
      return;
   }
   if (type != GL_UNSIGNED_BYTE &&
       type != GL_UNSIGNED_SHORT &&
       type != GL_UNSIGNED_INT) {
      _mesa_compile_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(type)");
      return;
   }
   if (end < start) {
      _mesa_compile_error(ctx, GL_INVALID_VALUE,
                          "glDrawRangeElements(end < start)");
      return;
   }

   if (save->out_of_memory)
      return;

   _save_OBE_DrawElements(mode, count, type, indices);
}


static void GLAPIENTRY
_save_OBE_MultiDrawElements(GLenum mode, const GLsizei *count, GLenum type,
                            const GLvoid * const *indices, GLsizei primcount)
{
   GET_CURRENT_CONTEXT(ctx);
   struct _glapi_table *dispatch = ctx->CurrentServerDispatch;
   GLsizei i;

   int vertcount = 0;
   for (i = 0; i < primcount; i++) {
      vertcount += count[i];
   }
   _ensure_draws_fits_in_storage(ctx, primcount, vertcount);

   for (i = 0; i < primcount; i++) {
      if (count[i] > 0) {
         CALL_DrawElements(dispatch, (mode, count[i], type, indices[i]));
      }
   }
}


static void GLAPIENTRY
_save_OBE_MultiDrawElementsBaseVertex(GLenum mode, const GLsizei *count,
                                      GLenum type,
                                      const GLvoid * const *indices,
                                      GLsizei primcount,
                                      const GLint *basevertex)
{
   GET_CURRENT_CONTEXT(ctx);
   struct _glapi_table *dispatch = ctx->CurrentServerDispatch;
   GLsizei i;

   int vertcount = 0;
   for (i = 0; i < primcount; i++) {
      vertcount += count[i];
   }
   _ensure_draws_fits_in_storage(ctx, primcount, vertcount);

   for (i = 0; i < primcount; i++) {
      if (count[i] > 0) {
         CALL_DrawElementsBaseVertex(dispatch, (mode, count[i], type,
                                                      indices[i],
                                                      basevertex[i]));
      }
   }
}


static void
vtxfmt_init(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   GLvertexformat *vfmt = &save->vtxfmt;

#define NAME_AE(x) _ae_##x
#define NAME_CALLLIST(x) _save_##x
#define NAME(x) _save_##x
#define NAME_ES(x) _save_##x##ARB

#include "vbo_init_tmp.h"
}


/**
 * Initialize the dispatch table with the VBO functions for display
 * list compilation.
 */
void
vbo_initialize_save_dispatch(const struct gl_context *ctx,
                             struct _glapi_table *exec)
{
   SET_DrawArrays(exec, _save_OBE_DrawArrays);
   SET_MultiDrawArrays(exec, _save_OBE_MultiDrawArrays);
   SET_DrawElements(exec, _save_OBE_DrawElements);
   SET_DrawElementsBaseVertex(exec, _save_OBE_DrawElementsBaseVertex);
   SET_DrawRangeElements(exec, _save_OBE_DrawRangeElements);
   SET_MultiDrawElementsEXT(exec, _save_OBE_MultiDrawElements);
   SET_MultiDrawElementsBaseVertex(exec, _save_OBE_MultiDrawElementsBaseVertex);
   SET_Rectf(exec, _save_OBE_Rectf);
   SET_Rectd(exec, _save_OBE_Rectd);
   SET_Rectdv(exec, _save_OBE_Rectdv);
   SET_Rectfv(exec, _save_OBE_Rectfv);
   SET_Recti(exec, _save_OBE_Recti);
   SET_Rectiv(exec, _save_OBE_Rectiv);
   SET_Rects(exec, _save_OBE_Rects);
   SET_Rectsv(exec, _save_OBE_Rectsv);

   /* Note: other glDraw functins aren't compiled into display lists */
}



void
vbo_save_SaveFlushVertices(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;

   /* Noop when we are actually active:
    */
   if (ctx->Driver.CurrentSavePrimitive <= PRIM_MAX)
      return;

   if (save->vert_count || save->prim_store->used)
      compile_vertex_list(ctx);

   copy_to_current(ctx);
   reset_vertex(ctx);
   ctx->Driver.SaveNeedFlush = GL_FALSE;
}


/**
 * Called from glNewList when we're starting to compile a display list.
 */
void
vbo_save_NewList(struct gl_context *ctx, GLuint list, GLenum mode)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;

   (void) list;
   (void) mode;

   if (!save->prim_store)
      save->prim_store = realloc_prim_store(NULL, 8);

   if (!save->vertex_store)
      save->vertex_store = realloc_vertex_store(NULL, save->vertex_size, 8);

   reset_vertex(ctx);
   ctx->Driver.SaveNeedFlush = GL_FALSE;
}


/**
 * Called from glEndList when we're finished compiling a display list.
 */
void
vbo_save_EndList(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;

   /* EndList called inside a (saved) Begin/End pair?
    */
   if (_mesa_inside_dlist_begin_end(ctx)) {
      if (save->prim_store->used > 0) {
         GLint i = save->prim_store->used - 1;
         ctx->Driver.CurrentSavePrimitive = PRIM_OUTSIDE_BEGIN_END;
         save->prim_store->prims[i].end = 0;
         save->prim_store->prims[i].count = save->vert_count - save->prim_store->prims[i].start;
      }

      /* Make sure this vertex list gets replayed by the "loopback"
       * mechanism:
       */
      save->dangling_attr_ref = GL_TRUE;
      vbo_save_SaveFlushVertices(ctx);

      /* Swap out this vertex format while outside begin/end.  Any color,
       * etc. received between here and the next begin will be compiled
       * as opcodes.
       */
      _mesa_install_save_vtxfmt(ctx, &ctx->ListState.ListVtxfmt);
   }

   assert(save->vertex_size == 0);
}

/**
 * Called during context creation/init.
 */
static void
current_init(struct gl_context *ctx)
{
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   GLint i;

   for (i = VBO_ATTRIB_POS; i <= VBO_ATTRIB_EDGEFLAG; i++) {
      const GLuint j = i - VBO_ATTRIB_POS;
      assert(j < VERT_ATTRIB_MAX);
      save->currentsz[i] = &ctx->ListState.ActiveAttribSize[j];
      save->current[i] = (fi_type *) ctx->ListState.CurrentAttrib[j];
   }

   for (i = VBO_ATTRIB_FIRST_MATERIAL; i <= VBO_ATTRIB_LAST_MATERIAL; i++) {
      const GLuint j = i - VBO_ATTRIB_FIRST_MATERIAL;
      assert(j < MAT_ATTRIB_MAX);
      save->currentsz[i] = &ctx->ListState.ActiveMaterialSize[j];
      save->current[i] = (fi_type *) ctx->ListState.CurrentMaterial[j];
   }
}


/**
 * Initialize the display list compiler.  Called during context creation.
 */
void
vbo_save_api_init(struct vbo_save_context *save)
{
   struct gl_context *ctx = gl_context_from_vbo_save(save);

   vtxfmt_init(ctx);
   current_init(ctx);
   _mesa_noop_vtxfmt_init(ctx, &save->vtxfmt_noop);
}