Noticed that gcc/g++ generate a branching sequence instead of straight-line code
for expressions of the form ABS(x-y). Changing the operator to something else
(+, *, /) resutls in straight-line code.


#define ABS(value)   ( (value)>=0 ? (value) : -(value) )
int i,j,k,l,m,n;

void f1()
{
  l = ABS(m+n);
  i = ABS(j-k);
}

-- 
           Summary: Branching sequence generated for ABS(x-y)
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pthaugen at us dot ibm dot com
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: powerpc*-*-*
  GCC host triplet: powerpc*-*-*
GCC target triplet: powerpc*-*-*


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20470

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