RealView Compilation Tools Compiler Reference Guide - ARM ...

Compiler-specific Features
sat must be in the range 1 to 32.
Return value
The __ssat intrinsic returns val saturated to the signed range –2 sat–1 ≤ x ≤ 2 sat–1 –1.
Errors
The compiler does not recognize the __ssat intrinsic when compiling for a target that
does not support the SSAT instruction. The compiler generates either a warning or an
error in this case.
See also
• __usat on page 4-93
• SSAT and USAT on page 4-96 in the Assembler Guide.
4.7.39 __strex
This intrinsic inserts an instruction of the form STREX{size} into the instruction stream
generated by the compiler. It enables you to use a STREX instruction in your C or C++
code to store data to memory.
Syntax
int __strex(unsigned int val, volatile void *ptr)
Where:
val
ptr
Is the value to be written to memory.
Points to the address of the data to be written to in memory. To specify
the size of the data to be written, cast the parameter to an appropriate
integral type.
Table 4-10 Access widths supported by the __strex intrinsic
Instruction Size of data loaded C cast
STREXB unsigned byte (char *)
STREXH unsigned halfword (short int *)
STREX word (int *)
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