RealView Compilation Tools Compiler Reference Guide - ARM ...

Compiler-specific Features
Where:
val1
val2
is the first summand of the saturating add operation
is the second summand of the saturating add operation.
Return value
The __qadd intrinsic returns the saturating add of val1 and val2.
See also
• __qdbl
• __qsub
• QADD, QSUB, QDADD, and QDSUB on page 4-94 in the Assembler Guide.
4.7.27 __qdbl
This intrinsic inserts instructions equivalent to the saturating add of an integer with itself
into the instruction stream generated by the compiler. It enables you to obtain the
saturating double of an integer from within your C or C++ code.
Syntax
int __qdbl(int val)
Where:
val
is the data value to be doubled.
Return value
The __qdbl intrinsic returns the saturating add of val with itself, or equivalently,
__qadd(val, val).
See also
• __qadd on page 4-80.
4.7.28 __qsub
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.
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