When you don’t have SSE4 available you have to compensate for the lack of ome essencial ops. In this series I’m going to write down equivalents of either missing or (currently) non-AMD ops.

pcmpeqq (64bit integer compare):

// equality == (hi == hi) && (lo == lo)

movdqa		xmm?3, xmma
pcmpeqd		xmm?3, xmmb
pshufd		xmm?1, xmm?3, 3|3|1|1	(b == a)
pshufd		xmm?2, xmm?3, 2|2|0|0	(B == A)
pand		xmm?1, xmm?2		(b == a) && (B == A)

pcmpgtq (64bit integer compare):

// greater == (hi > hi) || ((hi == hi) && (lo > lo))

movdqa		xmm?1, xmma
movdqa		xmm?2, xmma
pcmpgtd		xmm?1, xmmb
pcmpeqd		xmm?2, xmmb
pshufd		xmm?3, xmm?1, 3|3|1|1	(b > a)
pshufd		xmm?4, xmm?2, 3|3|1|1	(b == a)
por		xmm?2, xmm?1		(B > A) || (B == A)
pshufd		xmm?2, xmm?2, 2|2|0|0	(B >= A)
pand		xmm?2, xmm?4		(b == a) && (B >= A)
por		xmm?2, xmm?3		(b > a) || ((b == a) && (B >= A))