From d0fc57413e38fff62160baf72281f632d08da80d Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Thu, 3 Dec 2020 13:54:32 +0100
Subject: [PATCH] vkd3d: Merge adjacent query ranges on insertion.

Since we'll be inserting lots of single queries, we want to
avoid having to resize the range array since that is an O(n)
operation at worst.

Signed-off-by: Philip Rebohle <philip.rebohle@tu-dortmund.de>
---
 libs/vkd3d/command.c | 83 ++++++++++++++++++++++++++++++++++----------
 1 file changed, 65 insertions(+), 18 deletions(-)

diff --git a/libs/vkd3d/command.c b/libs/vkd3d/command.c
index 7e9371e7..874c34de 100644
--- a/libs/vkd3d/command.c
+++ b/libs/vkd3d/command.c
@@ -2989,24 +2989,69 @@ static bool d3d12_command_list_find_query(struct d3d12_command_list *list,
     return false;
 }
 
-static void d3d12_command_list_insert_query_range(struct d3d12_command_list *list, size_t pos,
+static void d3d12_command_list_insert_query_range(struct d3d12_command_list *list, size_t *where,
         VkQueryPool vk_pool, uint32_t index, uint32_t count, uint32_t flags)
 {
     struct vkd3d_query_range *range;
+    unsigned int move_count;
+    bool merge_lo, merge_hi;
+    size_t pos = *where;
 
-    vkd3d_array_reserve((void**)&list->query_ranges, &list->query_ranges_size,
-            list->query_ranges_count + 1, sizeof(*list->query_ranges));
+    merge_lo = false;
+    merge_hi = false;
 
-    for (size_t i = list->query_ranges_count; i > pos; i--)
-        list->query_ranges[i] = list->query_ranges[i - 1];
+    if (pos > 0)
+    {
+        range = &list->query_ranges[pos - 1];
+        merge_lo = range->flags == flags
+                && range->index + range->count == index;
+    }
 
-    range = &list->query_ranges[pos];
-    range->vk_pool = vk_pool;
-    range->index = index;
-    range->count = count;
-    range->flags = flags;
+    if (pos < list->query_ranges_count)
+    {
+        range = &list->query_ranges[pos];
+        merge_hi = range->flags == flags
+                && range->index == index + count;
+    }
 
-    list->query_ranges_count++;
+    /* The idea is that 'where' will point to the range that contains
+     * the original range it was pointing to before the insertion, which
+     * may be moved around depending on which ranges get merged. */
+    if (merge_lo)
+    {
+        range = &list->query_ranges[pos - 1];
+        range[0].count += count;
+
+        if (merge_hi)
+        {
+            range[0].count += range[1].count;
+            move_count = (--list->query_ranges_count) - pos;
+            memmove(&range[1], &range[2], sizeof(*range) * move_count);
+            (*where)--;
+        }
+    }
+    else if (merge_hi)
+    {
+        range = &list->query_ranges[pos];
+        range->index = index;
+        range->count += count;
+    }
+    else
+    {
+        vkd3d_array_reserve((void**)&list->query_ranges, &list->query_ranges_size,
+                list->query_ranges_count + 1, sizeof(*list->query_ranges));
+
+        range = &list->query_ranges[pos];
+        move_count = (list->query_ranges_count++) - pos;
+        memmove(range + 1, range, sizeof(*range) * move_count);
+
+        range->vk_pool = vk_pool;
+        range->index = index;
+        range->count = count;
+        range->flags = flags;
+
+        (*where)++;
+    }
 }
 
 static void d3d12_command_list_read_query_range(struct d3d12_command_list *list,
@@ -3022,8 +3067,9 @@ static void d3d12_command_list_read_query_range(struct d3d12_command_list *list,
      * location where we need to insert it */
     d3d12_command_list_find_query(list, vk_pool, index, &pos);
 
-    /* Do not attempt to merge adjacent ranges, but make sure
-     * that each query is only contained in one range */
+    /* Avoid overriding already existing ranges by splitting
+     * this range into pieces so that each query is contained
+     * in at most one range. */
     while (lo < hi)
     {
         if (pos < list->query_ranges_count)
@@ -3031,20 +3077,21 @@ static void d3d12_command_list_read_query_range(struct d3d12_command_list *list,
             range = &list->query_ranges[pos];
 
             if (lo >= range->index)
+            {
                 lo = max(lo, range->index + range->count);
+                pos += 1;
+            }
             else
             {
                 size_t range_end = min(hi, range->index);
-                d3d12_command_list_insert_query_range(list, pos,
+                d3d12_command_list_insert_query_range(list, &pos,
                         vk_pool, lo, range_end - lo, 0);
                 lo = range_end;
             }
-
-            pos += 1;
         }
         else
         {
-            d3d12_command_list_insert_query_range(list, pos,
+            d3d12_command_list_insert_query_range(list, &pos,
                     vk_pool, lo, hi - lo, 0);
             lo = hi;
         }
@@ -3059,7 +3106,7 @@ static bool d3d12_command_list_reset_query(struct d3d12_command_list *list,
     if (d3d12_command_list_find_query(list, vk_pool, index, &pos))
         return false;
 
-    d3d12_command_list_insert_query_range(list, pos,
+    d3d12_command_list_insert_query_range(list, &pos,
             vk_pool, index, 1, VKD3D_QUERY_RANGE_RESET);
     return true;
 }