Intel® C++ Compiler 16.0 User and Reference Guide

fast-transcendentals, Qfast-transcendentals

Enables the compiler to replace calls to transcendental functions with faster but less precise implementations.

Syntax

Linux and OS X:

-fast-transcendentals

-no-fast-transcendentals

Windows:

/Qfast-transcendentals

/Qfast-transcendentals-

Arguments

None

Default

depends on the setting of -fp-model (Linux* OS and OS X*) or /fp (Windows* OS)

If you do not specify option -[no-]fast-transcendentalsor option /Qfast-transcendentals[-]:

  • The default is ON if option -fp-model fast or /fp:fast is specified or is in effect.

  • The default is OFF if a value-safe setting is specified for -fp-model or /fp (such as "precise", "source", etc.).

Description

This option enables the compiler to replace calls to transcendental functions with implementations that may be faster but less precise.

It allows the compiler to perform certain optimizations on transcendental functions, such as replacing individual calls to sine in a loop with a single call to a less precise vectorized sine library routine.

This option does not affect explicit Short Vector Math Library (SVML) intrinsics. It only affects scalar calls to the standard math library routines.

You cannot use option –fast-transcendentals with option –fp-model strict and you cannot use option /Qfast-transcendentals with option /fp:strict.

This option determines the setting for the maximum allowable relative error for math library function results (max-error) if none of the following options are specified:

This option enables extra optimization that only applies to Intel® processors.

Optimization Notice

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804

IDE Equivalent

None

Alternate Options

None

Parent topic: Floating-Point Options

See Also

fp-model, fp compiler option
fimf-accuracy-bits, Qimf-accuracy-bits compiler option
fimf-max-error, Qimf-max-error compiler option
fimf-precision, Qimf-precision compiler option