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| Home > ARMv6 SIMD Instruction Intrinsics > __sadd16 intrinsic | |||
This intrinsic inserts an SADD16 instruction
into the instruction stream generated by the compiler. It enables
you to perform two 16-bit signed integer additions. The GE bits
in the APSR are set according to the results of the additions.
unsigned int __sadd16(unsigned intval1, unsigned intval2)
Where:
val1holds the first two 16-bit summands
val2holds the second two 16-bit summands.
The __sadd16 intrinsic returns:
the addition of the low halfwords in the low halfword of the return value
the addition of the high halfwords in the high halfword of the return value.
Each bit in APSR.GE is set or cleared for each byte in the
return value, depending on the results of the operation. If is
the return value, then:res
if [15:0]
≥ 0 then APSR.GE[1:0] = 11 else 00res
if [31:16]
≥ 0 then APSR.GE[3:2] = 11 else 00.res
Example:
unsigned int add_halfwords(unsigned int val1, unsigned int val2)
{
unsigned int res;
res = __sadd16(val1,val2); /* res[15:0] = val1[15:0] + val2[15:0]
res[31:16] = val1[31:16] + val2[31:16]
*/
return res;
}
Instruction summary in the Assembler Reference
Saturating instructions in the Assembler Reference
Parallel add and subtract in the Assembler Reference.