Re: Algoritmic Complexity Attacks and 2.4.20 the dcache code

[David S. Miller]

   From: Alex Riesen <[e-mail]>
   Date: Fri, 30 May 2003 10:59:01 +0200

       static
       int hash_3(int hi, int c)
       {
   	return (hi + (c << 4) + (c >> 4)) * 11;
       }
   
   gcc-3.2.1 -O2 -march=pentium
 ...   
   It is not guaranteed to be this way on all architectures, of course.
   But still - no multiplications.

Indeed, I'd missed this.  GCC will emit the constant multiply
expansion unless the multiply cost is set VERY low.