Fix crash with timestamp readback;

It's no longer used.

src/modules/graphics/graphics.c

@@ -1721,10 +1721,12 @@ void lovrGraphicsSubmit(Pass** passes, uint32_t count) {
     gpu_stream* stream = streams[streamCount++] = gpu_stream_begin(NULL);
 
     // Timestamp Readback
-    BufferView view = getBuffer(GPU_BUFFER_DOWNLOAD, 2 * count * sizeof(uint32_t), 4);
-    gpu_copy_tally_buffer(stream, state.timestamps, view.buffer, 0, view.offset, 2 * count);
-    Readback* readback = lovrReadbackCreateTimestamp(times, count, view);
-    lovrRelease(readback, lovrReadbackDestroy); // It gets freed when it completes
+    if (state.timingEnabled) {
+      BufferView view = getBuffer(GPU_BUFFER_DOWNLOAD, 2 * count * sizeof(uint32_t), 4);
+      gpu_copy_tally_buffer(stream, state.timestamps, view.buffer, 0, view.offset, 2 * count);
+      Readback* readback = lovrReadbackCreateTimestamp(times, count, view);
+      lovrRelease(readback, lovrReadbackDestroy); // It gets freed when it completes
+    }
 
     // OpenXR Swapchain Layout Transitions
     for (uint32_t i = 0; i < count; i++) {

src/util.c

@@ -129,32 +129,6 @@ void map_set(map_t* map, uint64_t hash, uint64_t value) {
   map->values[h] = value;
 }
 
-void map_remove(map_t* map, uint64_t hash) {
-  uint64_t h = map_find(map, hash);
-
-  if (map->hashes[h] == MAP_NIL) {
-    return;
-  }
-
-  uint64_t mask = map->size - 1;
-  uint64_t i = h;
-
-  do {
-    i = (i + 1) & mask;
-    uint64_t x = map->hashes[i] & mask;
-    // Removing a key from an open-addressed hash table is complicated
-    if ((i > h && (x <= h || x > i)) || (i < h && (x <= h && x > i))) {
-      map->hashes[h] = map->hashes[i];
-      map->values[h] = map->values[i];
-      h = i;
-    }
-  } while (map->hashes[i] != MAP_NIL);
-
-  map->hashes[i] = MAP_NIL;
-  map->values[i] = MAP_NIL;
-  map->used--;
-}
-
 // UTF-8
 // https://github.com/starwing/luautf8
 size_t utf8_decode(const char *s, const char *e, unsigned *pch) {

src/util.h

@@ -89,7 +89,7 @@ static inline void _arr_reserve(void** data, size_t n, size_t* capacity, size_t
   lovrAssert(*data, "Out of memory");
 }
 
-// Hashmap
+// Hashmap (does not support removal)
 typedef struct {
   uint64_t* hashes;
   uint64_t* values;
@@ -103,7 +103,6 @@ void map_init(map_t* map, uint32_t n);
 void map_free(map_t* map);
 uint64_t map_get(map_t* map, uint64_t hash);
 void map_set(map_t* map, uint64_t hash, uint64_t value);
-void map_remove(map_t* map, uint64_t hash);
 
 // UTF-8
 size_t utf8_decode(const char *s, const char *e, unsigned *pch);