[x265] [PATCH] asm: avx2 asm code for dct4

[Fiona Glaser]

+    movq            xm0, [r0]
+    movq            xm1, [r0 + r2]
+    punpcklqdq      m0, m1

These can be replaced by movq + movhps; it should be one less uop.

Fiona