1// Copyright 2009 The Go Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style 3// license that can be found in the LICENSE file. 4 5// Malloc small size classes. 6// 7// See malloc.go for overview. 8// See also mksizeclasses.go for how we decide what size classes to use. 9 10package runtime 11 12// Returns size of the memory block that mallocgc will allocate if you ask for the size. 13func roundupsize(size uintptr) uintptr { 14 if size < _MaxSmallSize { 15 if size <= smallSizeMax-8 { 16 return uintptr(class_to_size[size_to_class8[(size+smallSizeDiv-1)/smallSizeDiv]]) 17 } else { 18 return uintptr(class_to_size[size_to_class128[(size-smallSizeMax+largeSizeDiv-1)/largeSizeDiv]]) 19 } 20 } 21 if size+_PageSize < size { 22 return size 23 } 24 return round(size, _PageSize) 25} 26