modernc.org/gc@v1.0.1-0.20240304020402-f0dba7c97c2b/testdata/errchk/test/fixedbugs/issue12411.go (about)

     1  // +build !386
     2  // run
     3  
     4  // Copyright 2015 The Go Authors. All rights reserved.
     5  // Use of this source code is governed by a BSD-style
     6  // license that can be found in the LICENSE file.
     7  
     8  // Issue 12411. Loss of AX during %.
     9  
    10  package main
    11  
    12  func main() {
    13  	x := f(4)
    14  	if x != 0 {
    15  		println("BUG: x=", x)
    16  	}
    17  }
    18  
    19  //go:noinline
    20  func f(x int) int {
    21  	// AX was live on entry to one of the % code generations,
    22  	// and the % code generation smashed it.
    23  	return ((2 * x) % 3) % (2 % ((x << 2) ^ (x % 3)))
    24  }