-QSfast, -QSfastd - Provide Backward Compatibility (Windows CE 5.0)
These options, QSfast and QSfastd provide backward compatibility. /Qfastd is the default.
Microsoft® Windows® CE 3.0 and later operating systems support full IEEE compliant hardware operations including the use of denormal operands. This allows the compiler to default to use of the SH-4 hardware instructions for both single and double precision floating-point operations.
The –QSfast- option causes the compiler to call CRT emulation routines for all floating-point operations.
The -QSfast option allows the compiler to use single precision SH-4 floating-point instructions. It will also generate a warning if the compiler finds a double floating point constant.
Do not use double constants when performance is a consideration, because double constants can unnecessarily promote an operation-type from single to double precision.
Note Floating-point constants default to type double. You may specify single precision floating point constants with a floating suffix f or F such as 3.14159f.
The default /QSfastd command line option allows the compiler to use single and double precision SH-4 floating-point instructions.
The compiler does not generate warnings for double constants when you specify -QSfastd. The -QSfastd command line option may cause the compiler to produce slightly larger code.
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