This content has not been validated; it was AI-generated following the x86-64 ISA Documentation generation process to maintain high quality. However, as no human has verified this data, errors may exist. If the accuracy of this data is critical, please consult the Intel SDM. The model used to generate this is gemma4:31b

PADDSB

Adds unsigned 8-bit integers from a source to a destination in a SIMD manner, with saturation. If the result of an addition exceeds 255, it is clamped to 255.

The table after the description covers what the source and destinations can be.

DO NOT support LOCK

This instruction is only available in 64-bit mode or compatibility mode. It requires the SSE2 instruction set extension.

The destination register is overwritten by the result. Because this is a saturated addition, unsigned overflow does not trigger the CPU flags (such as CF or OF). Users MUST ensure that the data is aligned to 16-byte boundaries when using aligned load/store instructions surrounding this operation to avoid performance degradation or general protection faults.