blob: 3a4c7d0fc375230d5dc0baaab3de6d19be79ee99 [file] [log] [blame]
// Copyright 2024 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 runtime_test
import (
. "runtime"
"testing"
)
func TestBitCursor(t *testing.T) {
ones := [5]byte{0xff, 0xff, 0xff, 0xff, 0xff}
zeros := [5]byte{0, 0, 0, 0, 0}
for start := uintptr(0); start < 16; start++ {
for end := start + 1; end < 32; end++ {
buf := zeros
NewBitCursor(&buf[0]).Offset(start).Write(&ones[0], end-start)
for i := uintptr(0); i < uintptr(len(buf)*8); i++ {
bit := buf[i/8] >> (i % 8) & 1
if bit == 0 && i >= start && i < end {
t.Errorf("bit %d not set in [%d:%d]", i, start, end)
}
if bit == 1 && (i < start || i >= end) {
t.Errorf("bit %d is set outside [%d:%d]", i, start, end)
}
}
}
}
for start := uintptr(0); start < 16; start++ {
for end := start + 1; end < 32; end++ {
buf := ones
NewBitCursor(&buf[0]).Offset(start).Write(&zeros[0], end-start)
for i := uintptr(0); i < uintptr(len(buf)*8); i++ {
bit := buf[i/8] >> (i % 8) & 1
if bit == 1 && i >= start && i < end {
t.Errorf("bit %d not cleared in [%d:%d]", i, start, end)
}
if bit == 0 && (i < start || i >= end) {
t.Errorf("bit %d cleared outside [%d:%d]", i, start, end)
}
}
}
}
}