x86 failure on loop reversal

[Jeffrey A Law]

  In message < 199804071327.OAA09064@phal.cygnus.co.uk >you write:
  > Here is a version of the testcase that avoids the -0x80000000 problem:
  > 
  > int
  > f()
  > {
  >   int j = 1;
  >   long i;
  >   for (i = -0x70000000L; i < 0x60000000L; i += 0x10000000L) j <<= 1;
  >   return j;
  > }
  > 
  > int
  > main ()
  > {
  >   if (f () != 8192)
  >     abort ();
  >   return 0;
  > }
I added this test to the testsuite.

jeff