Intrinsic Functions for ARM Microprocessors
The ARM device compiler supports a set of intrinsic functions that are defined for specific ARM microprocessors.
Different sets of intrinsic functions are available for the ARM10, the ARM DSP, the ARM XSCALE, and the Intel PXA270 architectures.
The ARM compiler uses the /QR compiler option to determine which set of intrinsic functions to chose for a particular compilation. For example, the /QRxscale enables the XScale MAC intrinsic functions. For more information about the /QR flag, see ARM Compiler Options.
If appropriate target architecture is not defined, some intrinsic functions, such as XScale MAC functions, will fail.
To guard an intrinsic function, or to ensure that an intrinsic function is called only if a specific target architecture is defined, use the system management function IsProcessorFeaturePresent. For more information about this function, see this Microsoft Web site.