/// Allocate - Allocate space at the specified alignment.
///
void *BumpPtrAllocator::Allocate(size_t Size, size_t Alignment) {
+ // 0-byte alignment means 1-byte alignment.
+ if (Alignment == 0) Alignment = 1;
+
+ size_t PaddedSize = Size + sizeof(MemSlab) + Alignment - 1;
+
+ // If requested size exceeds slab size, increase slab size.
+ while (PaddedSize > SlabSize)
+ SlabSize *= 2;
+
if (!CurSlab) // Start a new slab if we haven't allocated one already.
StartNewSlab();
// Keep track of how many bytes we've allocated.
BytesAllocated += Size;
- // 0-byte alignment means 1-byte alignment.
- if (Alignment == 0) Alignment = 1;
-
// Allocate the aligned space, going forwards from CurPtr.
char *Ptr = AlignPtr(CurPtr, Alignment);
}
// If Size is really big, allocate a separate slab for it.
- size_t PaddedSize = Size + sizeof(MemSlab) + Alignment - 1;
if (PaddedSize > SizeThreshold) {
MemSlab *NewSlab = Allocator.Allocate(PaddedSize);
EXPECT_EQ(2U, Alloc.GetNumSlabs());
}
+// Test allocating with a size larger than the initial slab size.
+TEST(AllocatorTest, TestSmallSlabSize) {
+ BumpPtrAllocator Alloc(128);
+
+ Alloc.Allocate(200, 0);
+ EXPECT_EQ(1U, Alloc.GetNumSlabs());
+}
+
// Mock slab allocator that returns slabs aligned on 4096 bytes. There is no
// easy portable way to do this, so this is kind of a hack.
class MockSlabAllocator : public SlabAllocator {