// f := f1 - 1
	SUBSD   X0, X2 // x1= k, x2= f
	// s := f / (2 + f)
	MOVSD   $2.0, X0
	ADDSD   X2, X0
	MOVAPD  X2, X3
	DIVSD   X0, X3 // x1=k, x2= f, x3= s
	// s2 := s * s
	MOVAPD  X3, X4 // x1= k, x2= f, x3= s
	MULSD   X4, X4 // x1= k, x2= f, x3= s, x4= s2
	// s4 := s2 * s2
	MOVAPD  X4, X5 // x1= k, x2= f, x3= s, x4= s2
	MULSD   X5, X5 // x1= k, x2= f, x3= s, x4= s2, x5= s4
	// t1 := s2 * (L1 + s4*(L3+s4*(L5+s4*L7)))

	MOVQ    $PosInf, AX
	CMPQ    AX, BX
	JLE     isInfOrNaN
	CMPQ    AX, CX
	JLE     isInfOrNaN
	// hypot = max * sqrt(1 + (min/max)**2)
	MOVQ    BX, X0
	MOVQ    CX, X1
	ORQ     CX, BX
	JEQ     isZero
	MOVAPD  X0, X2
	MAXSD   X1, X0
	MINSD   X2, X1
	DIVSD   X0, X1
	MULSD   X1, X1
	ADDSD   $1.0, X1
	SQRTSD  X1, X1
	MULSD   X1, X0
	MOVSD   X0, ret+16(FP)
	RET
isInfOrNaN:
	CMPQ    AX, BX
	JEQ     isInf

	"LZCNTL",
	"LZCNTQ",
	"LZCNTW",
	"MASKMOVOU",
	"MASKMOVQ",
	"MAXPD",
	"MAXPS",
	"MAXSD",
	"MAXSS",
	"MFENCE",
	"MINPD",
	"MINPS",
	"MINSD",
	"MINSS",
	"MONITOR",
	"MOVAPD",
	"MOVAPS",
	"MOVB",
	"MOVBEL",
	"MOVBEQ",
	"MOVBEW",
	"MOVBLSX",
	"MOVBLZX",
	"MOVBQSX",
	"MOVBQZX",
	"MOVBWSX",
	"MOVBWZX",
	"MOVDDUP",
	"MOVHLPS",
	"MOVHPD",

	MOVAPD (BX), X2                         // 660f2813
	MOVAPD (R11), X2                        // 66410f2813
	MOVAPD X2, X2                           // 660f28d2 or 660f29d2
	MOVAPD X11, X2                          // 66410f28d3 or 66440f29da
	MOVAPD (BX), X11                        // 66440f281b
	MOVAPD (R11), X11                       // 66450f281b

	MFENCE:          "MFENCE",
	MINPD:           "MINPD",
	MINPS:           "MINPS",
	MINSD:           "MINSD",
	MINSS:           "MINSS",
	MONITOR:         "MONITOR",
	MOV:             "MOV",
	MOVAPD:          "MOVAPD",
	MOVAPS:          "MOVAPS",
	MOVBE:           "MOVBE",
	MOVD:            "MOVD",
	MOVDDUP:         "MOVDDUP",
	MOVDQ2Q:         "MOVDQ2Q",
	MOVDQA:          "MOVDQA",