Changeset 2781 in webkit for trunk/JavaScriptCore/kjs/collector.cpp

Timestamp:

Nov 20, 2002, 8:54:45 AM (23 years ago)

Author:

mjs

Message:

Fixed the two most obvious problems with the new GC for another 6%
improvement.

• kjs/collector.cpp: (Collector::allocate): Don't bother doing the bit tests on a bitmap word if all it's bits are on. (Collector::collect): Track memoryFull boolean.
• kjs/collector.h: Inlined outOfMemory since it was showing up on profiles.

File:

• trunk/JavaScriptCore/kjs/collector.cpp (modified) (6 diffs)

trunk/JavaScriptCore/kjs/collector.cpp

@@ -44 +44 @@
 static const int WORD_SIZE = sizeof(uint32_t);
 static const int BITS_PER_WORD = WORD_SIZE * 8;
+static const uint32_t ALL_BITS_ON = 0xffffffff;
 static const int CELLS_PER_BLOCK = ((BLOCK_SIZE * 8 - 32) / (CELL_SIZE * 8 + 1));
 static const int BITMAP_SIZE = (CELLS_PER_BLOCK / BITS_PER_WORD) + (CELLS_PER_BLOCK % BITS_PER_WORD != 0 ? 1 : 0);
@@ -77 +78 @@
 static CollectorHeap heap = {NULL, 0, 0, NULL, 0, 0, 0, 0};
 
+bool Collector::memoryFull = false;
+
+
 void* Collector::allocate(size_t s)
 {
@@ -86 +90 @@
     collect();
   
-  heap.numLiveObjects++;
-
-  if (heap.numLiveObjects >= KJS_MEM_LIMIT) {
-    // fprintf(stderr,"Out of memory");
-  }
-
-
   if (s > (unsigned)CELL_SIZE) {
     // oversize allocator
@@ -135 +132 @@
   for (int wordInBitmap = 0; wordInBitmap < BITMAP_SIZE; wordInBitmap++) {
     uint32_t word = targetBlock->bitmap[wordInBitmap];
+    if (word == ALL_BITS_ON) {
+      continue;
+    }
     for (int bitInWord = 0; bitInWord < BITS_PER_WORD; bitInWord++) {
       if ((word & (1 << bitInWord)) == 0) {
@@ -276 +276 @@
   heap.numAllocationsSinceLastCollect = 0;
   
+  memoryFull = (heap.numLiveObjects >= KJS_MEM_LIMIT);
+
   return deleted;
 }
@@ -282 +284 @@
 {
   return heap.numLiveObjects; 
-}
-
-bool Collector::outOfMemory() 
-{
-  return heap.numLiveObjects >= KJS_MEM_LIMIT;
 }