qurl/vendor/go.etcd.io/bbolt/bolt_arm.go
2018-11-12 01:56:30 +00:00

29 lines
832 B
Go

package bbolt
import "unsafe"
// maxMapSize represents the largest mmap size supported by Bolt.
const maxMapSize = 0x7FFFFFFF // 2GB
// maxAllocSize is the size used when creating array pointers.
const maxAllocSize = 0xFFFFFFF
// Are unaligned load/stores broken on this arch?
var brokenUnaligned bool
func init() {
// Simple check to see whether this arch handles unaligned load/stores
// correctly.
// ARM9 and older devices require load/stores to be from/to aligned
// addresses. If not, the lower 2 bits are cleared and that address is
// read in a jumbled up order.
// See http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka15414.html
raw := [6]byte{0xfe, 0xef, 0x11, 0x22, 0x22, 0x11}
val := *(*uint32)(unsafe.Pointer(uintptr(unsafe.Pointer(&raw)) + 2))
brokenUnaligned = val != 0x11222211
}