var b = make([]byte, 1.0<<s)   // 1.0 has type int; len(b) == 1<<33

// The results of the following examples are given for 32-bit ints,
// which means the shifts will overflow.
var mm int = 1.0<<s            // 1.0 has type int; mm == 0
var oo = 1<<s == 2<<s          // 1 and 2 have type int; oo == true
var pp = 1<<s == 1<<33         // illegal: 1 has type int, but 1<<33 overflows int

			rexX = 0
		} else if regrex[rm.Index]&Rxx != 0 {
			rexX = 0
		}
		if regrex[rm.Reg]&Rxb != 0 {
			rexB = 0
		}
	}
	// P0 = [R][X][B][R'][00][mm]
	p0 := (rexR << 7) |
		(rexX << 6) |
		(rexB << 5) |
		(evexR << 4) |
		(0 << 2) |
		(evex.M() << 0)

	vexV := byte(0)
	if v != nil {
		// 4bit-wide reg index.