| // Copyright 2017 The Go Authors. All rights reserved. | |
| // Use of this source code is governed by a BSD-style | |
| // license that can be found in the LICENSE file. | |
| package ir | |
| type bitset8 uint8 | |
| func (f *bitset8) set(mask uint8, b bool) { | |
| if b { | |
| *(*uint8)(f) |= mask | |
| } else { | |
| *(*uint8)(f) &^= mask | |
| } | |
| } | |
| func (f bitset8) get2(shift uint8) uint8 { | |
| return uint8(f>>shift) & 3 | |
| } | |
| // set2 sets two bits in f using the bottom two bits of b. | |
| func (f *bitset8) set2(shift uint8, b uint8) { | |
| // Clear old bits. | |
| *(*uint8)(f) &^= 3 << shift | |
| // Set new bits. | |
| *(*uint8)(f) |= uint8(b&3) << shift | |
| } | |
| type bitset16 uint16 | |
| func (f *bitset16) set(mask uint16, b bool) { | |
| if b { | |
| *(*uint16)(f) |= mask | |
| } else { | |
| *(*uint16)(f) &^= mask | |
| } | |
| } | |
| type bitset32 uint32 | |
| func (f *bitset32) set(mask uint32, b bool) { | |
| if b { | |
| *(*uint32)(f) |= mask | |
| } else { | |
| *(*uint32)(f) &^= mask | |
| } | |
| } | |
| func (f bitset32) get2(shift uint8) uint8 { | |
| return uint8(f>>shift) & 3 | |
| } | |
| // set2 sets two bits in f using the bottom two bits of b. | |
| func (f *bitset32) set2(shift uint8, b uint8) { | |
| // Clear old bits. | |
| *(*uint32)(f) &^= 3 << shift | |
| // Set new bits. | |
| *(*uint32)(f) |= uint32(b&3) << shift | |
| } | |
| func (f bitset32) get3(shift uint8) uint8 { | |
| return uint8(f>>shift) & 7 | |
| } | |
| // set3 sets three bits in f using the bottom three bits of b. | |
| func (f *bitset32) set3(shift uint8, b uint8) { | |
| // Clear old bits. | |
| *(*uint32)(f) &^= 7 << shift | |
| // Set new bits. | |
| *(*uint32)(f) |= uint32(b&7) << shift | |
| } |