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xmm register

One of x86-64's 16 registers (xmm0 to xmm15) for floating-point and SIMD values; scalar code uses only the low 32 or 64 bits.

The xmm registers are the 128-bit SSE registers xmm0-xmm15 (the low halves of AVX's ymm/zmm); scalar SSE instructions read and write their low float or double lane.

Examples

  • addsd xmm0, xmm1 adds the low double of xmm1 to the low double of xmm0.

See also

SSE floating-point register
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