diff options
Diffstat (limited to 'pkg/atomicbitops/aligned_32bit_unsafe.go')
| -rw-r--r-- | pkg/atomicbitops/aligned_32bit_unsafe.go | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/pkg/atomicbitops/aligned_32bit_unsafe.go b/pkg/atomicbitops/aligned_32bit_unsafe.go index 383f81ff2..a17d317cc 100644 --- a/pkg/atomicbitops/aligned_32bit_unsafe.go +++ b/pkg/atomicbitops/aligned_32bit_unsafe.go @@ -34,14 +34,15 @@ import ( // // +stateify savable type AlignedAtomicInt64 struct { - value [15]byte + value int64 + value32 int32 } func (aa *AlignedAtomicInt64) ptr() *int64 { - // In the 15-byte aa.value, there are guaranteed to be 8 contiguous - // bytes with 64-bit alignment. We find an address in this range by - // adding 7, then clear the 3 least significant bits to get its start. - return (*int64)(unsafe.Pointer((uintptr(unsafe.Pointer(&aa.value[0])) + 7) &^ 7)) + // On 32-bit systems, aa.value is is guaranteed to be 32-bit aligned. + // It means that in the 12-byte aa.value, there are guaranteed to be 8 + // contiguous bytes with 64-bit alignment. + return (*int64)(unsafe.Pointer((uintptr(unsafe.Pointer(&aa.value)) + 4) &^ 7)) } // Load is analagous to atomic.LoadInt64. @@ -71,14 +72,15 @@ func (aa *AlignedAtomicInt64) Add(v int64) int64 { // // +stateify savable type AlignedAtomicUint64 struct { - value [15]byte + value uint64 + value32 uint32 } func (aa *AlignedAtomicUint64) ptr() *uint64 { - // In the 15-byte aa.value, there are guaranteed to be 8 contiguous - // bytes with 64-bit alignment. We find an address in this range by - // adding 7, then clear the 3 least significant bits to get its start. - return (*uint64)(unsafe.Pointer((uintptr(unsafe.Pointer(&aa.value[0])) + 7) &^ 7)) + // On 32-bit systems, aa.value is is guaranteed to be 32-bit aligned. + // It means that in the 12-byte aa.value, there are guaranteed to be 8 + // contiguous bytes with 64-bit alignment. + return (*uint64)(unsafe.Pointer((uintptr(unsafe.Pointer(&aa.value)) + 4) &^ 7)) } // Load is analagous to atomic.LoadUint64. |