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Compiler-specific Features
||foo|| PROC
MOV r1, #0xff
MOV r0, #0x20
SWP r0, r0, [r1]
BX lr
ENDP
See also
• SWP and SWPB on page 4-40 in the Assembler Guide.
4.7.40 __usat
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.
Syntax
int __usat(unsigned int val, unsigned int sat)
Where:
val
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 ≤ 2 sat–1 –1.
Errors
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.
See also
• __ssat on page 4-100
• SSAT and USAT on page 4-96 in the Assembler Guide.
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