RealView Compilation Tools Compiler Reference Guide - ARM ...

Compiler-specific Features
Syntax
int __qsub(int val1, int val2)
Where:
val1
val2
is the minuend of the saturating subtraction operation
is the subtrahend of the saturating subtraction operation.
Return value
The __qsub intrinsic returns the saturating subtraction of val1 and val2.
See also
• __qadd on page 4-80
• QADD, QSUB, QDADD, and QDSUB on page 4-94 in the Assembler Guide.
4.7.29 __rbit
This intrinsic inserts an RBIT instruction into the instruction stream generated by the
compiler. It enables you to reverse the bit order in a 32-bit word from within your C or
C++ code.
Syntax
unsigned int __rbit(unsigned int val)
where:
val
is the data value whose bit order is to be reversed.
Return value
The __rbit intrinsic returns the value obtained from val by reversing its bit order.
See also
• REV, REV16, REVSH, and RBIT on page 4-64 in the Assembler Guide.
4.7.30 __rev
This intrinsic inserts a REV instruction or an equivalent code sequence into the
instruction stream generated by the compiler. It enables you to convert a 32-bit
big-endian data value into a little-endian data value, or a 32-bit little-endian data value
into big-endian data value from within your C or C++ code.
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