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/* { dg-do run } */
/* We don't (and don't want to) perform this optimisation on soft-float targets,
where each addition is a library call. /
/* { dg-require-effective-target hard_float } */
/* -fassociative-math requires -fno-trapping-math and -fno-signed-zeros. */
/* { dg-options "-O2 -funroll-loops -fassociative-math -fno-trapping-math -fno-signed-zeros -fvariable-expansion-in-unroller -fdump-rtl-loop2_unroll" } */
extern void abort (void);
extern void exit (int);
float __attribute__((noinline))
foo (float d, int n)
{
unsigned i;
float accum = d;
for (i = 0; i < n; i++)
accum += d;
return accum;
}
int
main ()
{
/* When compiling standard compliant we expect foo to return -0.0. But the
variable expansion during unrolling optimization (for this testcase enabled
by non-compliant -fassociative-math) instantiates copy(s) of the
accumulator which it initializes with +0.0. Hence we expect that foo
returns +0.0. */
if (__builtin_copysignf (1.0, foo (0.0 / -5.0, 10)) != 1.0)
abort ();
exit (0);
}
/* { dg-final { scan-rtl-dump "Expanding Accumulator" "loop2_unroll" } } */
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