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// 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
}
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