Selects faster, less accurate or slower, more precise floating-point math.
Syntax
Parameters
mode
The floating point mode: FAST | PRECISE.
Description
The
-fpmode compiler option specifies whether speed or precision is more important for floating point math. If this option is not specified, the default is
-fpmode PRECISE.
-fpmode FAST will generate faster, less accurate instructions for certain floating point operations.
-fpmode PRECISE will generate standard floating point instructions that operate at the default speed and accuracy of the selected floating point unit.
Currently, the only floating point operations that behave differently when using
-fpmode FAST are:
Sin(),
Cos(), reciprocal, and reciprocal
Square Root, all of which must operate on
Single precision values.
Using
-fpmode PRECISE is dependent on the
-fpu SSE command line option. Using
-fpmode PRECISE without using
-fpu SSE will generate an error.
See also