Intel MMX Instruction Set
64-bit SIMD register (4 data types)
- 64-bit quad word
- Packed byte (8 bytes packed into 64 bits)
- Packed word (4 16-bit words packed into 64 bits)
- Packed double word (2 double words packed into 64 bits)
57 new instructions
- Pack and unpack
- Add, subtract, multiply, and multiply/accumulate
Saturation and wraparound arithmetic
Maximum parallelism possible
- 8:1 for 8-bit additions
- 4:1 for 8 x 16 multiplication or 16-bit additions