Denormal paths speedup in VML by setting FTZ/DAZ setting

Intel® MKL VML accuracy setting mode variable is extended with a new setting from Intel MKL 11.3 onwards.

Users can turn ON or OFF this setting by using VML_FTZDAZ_ON / VML_FTZDAZ_OFF (default) in VML functions.

VML_FTZDAZ_ON mode improves performance of computations that involve denormalized numbers at the cost of reasonable accuracy loss.

Enabling this mode changes numerical behavior of the functions:  denormalized input values may be treated as zeros and denormalized results may flush to zero.  Accuracy loss may occur if input and/or output values are close to denormal range.

Usage example:

vmlSetMode( VML_LA | VML_FTZDAZ_ON);

vmdExp(1000, a, r, VML_LA | VML_FTZDAZ_ON);



Optimization Notice in English