/* $Id: transformations.c 70049 2014-06-03 13:52:49Z vinc17/ypig $
 *
 * Test common transformations. See:
 *   https://gcc.gnu.org/wiki/FloatingPointMath
 *
 * For x / C where C is a power of 2, see file "div-by-powof2.c".
 *
 * The simplication is done except when it violates some flag:
 *   SNAN means HONOR_SNANS (-fsignaling-nans)
 *   NAN means HONOR_NANS (-fno-finite-math-only [default])
 *   SZ means HONOR_SIGNED_ZEROS (-fsigned-zeros [default])
 *   RM means HONOR_SIGN_DEPENDENT_ROUNDING (-frounding-math)
 *
 * A NAN violation implies a SNAN violation.
 *
 * SZ+RM means that both HONOR_SIGNED_ZEROS and HONOR_SIGN_DEPENDENT_ROUNDING
 * must be true to be violated and disable the transformation.
 *
 * With gcc 4.10.0 20140508 [trunk revision 210211], neither x_add_zero,
 * nor x_sub_zero transformations violate SNAN, which is a bug.
 *
 * To check the fold-const.c implementation:
 *   x_add_zero, x_sub_zero: fold_real_zero_addition_p
 */

/* For asm comparison with the following. */
double id (double x) { return x; }

/*                                                   Violates */
double x_add_zero (double x) { return x + 0.0; }  /* SNAN, SZ */
double x_sub_zero (double x) { return x - 0.0; }  /* SNAN, SZ+RM */
double zero_sub_x (double x) { return 0.0 - x; }  /* SNAN, SZ */
double zero_mul_x (double x) { return 0.0 * x; }  /* NAN,  SZ */
double zero_div_x (double x) { return 0.0 / x; }  /* NAN,  SZ */
double x_mul_one  (double x) { return x * 1.0; }  /* SNAN */
double x_mul_mone (double x) { return x * -1.0; } /* SNAN */
double x_div_one  (double x) { return x / 1.0; }  /* SNAN */
double x_div_mone (double x) { return x / -1.0; } /* SNAN */