// Copyright 2025 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.

//go:build (!amd64 && !arm64) || purego

package bitutil

import "unsafe"

func testBytes(p []byte) bool {
	if supportsUnaligned {
		return fastTestBytes(p)
	}
	return safeTestBytes(p)
}

// fastTestBytes tests for set bits in bulk. It only works on architectures that
// support unaligned read/writes.
func fastTestBytes(p []byte) bool {
	n := len(p)
	w := n / wordSize
	if w > 0 {
		pw := *(*[]uintptr)(unsafe.Pointer(&p))
		for i := 0; i < w; i++ {
			if pw[i] != 0 {
				return true
			}
		}
	}
	for i := n - n%wordSize; i < n; i++ {
		if p[i] != 0 {
			return true
		}
	}
	return false
}