Function cpf_mul

Function Documentation

static inline int cpf_mul(double *X, const double *A, const double *B, const size_t numelem, optstruct *fpopts)

Compute product in lower precision.

If the function executes without errors, then \( X_i = A_i \times B_i \) rounded to a lower-precision target format. The parameters of the target format and the rounding mode to be used are encoded in fpopts. If required, the function flips one bit in some of the entries of X.

If OpenMP support is specified at compile time, several OpenMP threads are used if numelem is large enough. This parameter is machine dependent.

Parameters:

  • X – [out] Array of rounded values.

  • A – [in] Input array.

  • B – [in] Input array.

  • numelem – [in] Number of elements in X, A, and B.

  • fpopts – [in] Parameters describing the target format, the rounding mode, and the probability of soft errors striking the rounded values.

Returns:

The function returns 1 if fpopts->precision is larger than 53 , 2 if fptops->emin is smaller than -1022 or fpopts->emax is larger than 1023 , and 0 otherwise.