10.129 __rbit intrinsic

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.

Errors

The compiler does not recognize the __rbit intrinsic when compiling for a target that does not support the RBIT instruction. The compiler generates either a warning or an error in this case, depending on the source language:

  • In C code: Warning: #223-D: function "__rbit" declared implicitly.
  • In C++ code: Error: #20: identifier "__rbit" is undefined.
Related information
RBIT
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