For IA-32 and x64 code, is similar to and the original x64 calling conventions respectively, but extends them to support passing vector arguments using SIMD registers. In IA-32, the integer values are passed as usual, and the first six SIMD (XMM/YMM0-5) registers hold up to six floating-point, vector, or HVA values sequentially from left to right, regardless of actual positions caused by, e.g. an int argument appearing between them. In x64, however, the rule from the original x64 convention still apply, so that XMM/YMM0-5 only hold floating-point, vector, or HVA arguments when they happen to be the first through the sixth.