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// run
// Copyright 2012 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.
// Issue 4448: 64-bit indices that are statically known
// to be bounded make 5g and 8g generate a dangling branch.
package main
const b26 uint64 = 0x022fdd63cc95386d
var bitPos [64]int
func init() {
for p := uint(0); p < 64; p++ {
bitPos[b26<<p>>58] = int(p)
}
}
func MinPos(w uint64) int {
if w == 0 {
panic("bit: MinPos(0) undefined")
}
return bitPos[((w&-w)*b26)>>58]
}
func main() {
const one = uint64(1)
for i := 0; i < 64; i++ {
if MinPos(1<<uint(i)) != i {
println("i =", i)
panic("MinPos(1<<uint(i)) != i")
}
}
}
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