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A Portable SWAR Model

• Manufacturer SWAR support is machine dependent
  • Different (often irregular) instructions
  • Different width registers, fields
  • Different register use constraints
    (e.g., can't mix MMX with floating point)
  • HLL models specify each instruction
• Need complete SIMD/vector features
• Need variable size/parallelism-width data
• Cannot have HLL-visible "holes"
  (i.e., omit quirky SWAR instructions)