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Compiler-specific Features
4.7.78 __ssat16 intrinsic
This intrinsic inserts an SSAT16 instruction into the instruction stream generated by the
compiler. It enables you to saturate two signed 16-bit values to a selected signed range.
The Q bit is set if either operation saturates.
unsigned int __saturate_halfwords(unsigned int val1, unsigned int val2)
Where:
val1
val2
holds the two signed 16-bit values to be saturated
is the bit position for saturation, an integral constant expression in the
range 1 to 16.
The __ssat16 intrinsic returns:
• the signed saturation of the low halfword in val1, saturated to the bit position
specified in val2 and returned in the low halfword of the return value
• the signed saturation of the high halfword in val1, saturated to the bit position
specified in val2 and returned in the high halfword of the return value.
Example:
unsigned int saturate_halfwords(unsigned int val1, unsigned int val2)
{
unsigned int res;
}
res = __ssat16(val1,val2); /* Saturate halfwords in val1 to the signed
range specified by the bit position in val2 */
return res;
See also
• ARMv6 SIMD intrinsics on page 4-109
• Instruction summary on page 4-2 in the Assembler Guide
• Saturating instructions on page 4-93 in the Assembler Guide
• SSAT16 and USAT16 on page 4-104 in the Assembler Guide.
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