10.143 __usat intrinsic

This intrinsic inserts a USAT instruction into the instruction stream generated by the compiler.

It enables you to saturate an unsigned value from within your C or C++ code.


int __usat(unsigned int val, unsigned int sat)



Is the value to be saturated.


Is the bit position to saturate to.

usat must be in the range 0 to 31.

Return value

The __usat intrinsic returns val saturated to the unsigned range 0 ≤ x ≤ 2sat –1.


The compiler does not recognize the __usat intrinsic when compiling for a target that does not support the USAT 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 "__usat" declared implicitly.
  • In C++ code: Error: #20: identifier "__usat" is undefined.
Related reference
10.138 __ssat intrinsic
Related information
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