This intrinsic inserts a QSUB instruction or
an equivalent code sequence into the instruction stream generated
by the compiler. It enables you to obtain the saturating subtraction
of two integers from within your C or C++ code.
Syntax
int __qsub(int val1, int val2)
where:
val1
is the minuend of the saturating subtraction operation
val2
is the subtrahend of the saturating subtraction
operation.
Return value
The __qsub intrinsic returns the saturating
subtraction of val1 and val2.