MOVQ    BX, X0
	MOVQ    $0x000FFFFFFFFFFFFF, AX
	MOVQ    AX, X2
	ANDPD   X0, X2
	MOVSD   $0.5, X0 // 0x3FE0000000000000
	ORPD    X0, X2 // X2= f1
	SHRQ    $52, BX
	ANDL    $0x7FF, BX
	SUBL    $0x3FE, BX
	XORPS   X1, X1 // break dependency for CVTSL2SD
	CVTSL2SD BX, X1 // x1= k, x2= f1
	// if f1 < math.Sqrt2/2 { k -= 1; f1 *= 2 }
	MOVSD   $HSqrt2, X0 // x0= 0.7071, x1= k, x2= f1
	CMPSD   X2, X0, 5 // cmpnlt; x0= 0 or ^0, x1= k, x2 = f1

	PUSH_REGS_HOST_TO_ABI0()

	// Set up ABIInternal environment: cleared X15 and R14.
	// R14 is cleared in case there's a non-zero value in there
	// if called from a non-go thread.
	XORPS	X15, X15
	XORQ	R14, R14

	get_tls(AX)
	CMPQ	AX, $0
	JE	2(PC)
	// Exception from Go thread, set R14.
	MOVQ	g(AX), R14

	// Reserve space for spill slots.
	ADJSP	$16
	MOVQ	CX, AX

	"XADDB",
	"XADDL",
	"XADDQ",
	"XADDW",
	"XBEGIN",
	"XCHGB",
	"XCHGL",
	"XCHGQ",
	"XCHGW",
	"XEND",
	"XGETBV",
	"XLAT",
	"XORB",
	"XORL",
	"XORPD",
	"XORPS",
	"XORQ",
	"XORW",
	"XRELEASE",
	"XRSTOR",
	"XRSTOR64",
	"XRSTORS",
	"XRSTORS64",
	"XSAVE",
	"XSAVE64",
	"XSAVEC",
	"XSAVEC64",
	"XSAVEOPT",
	"XSAVEOPT64",

	MOVQ	(g_sched+gobuf_sp)(R10), SP
call:
	ANDQ	$~15, SP	// alignment for gcc ABI
	CALL	AX
	MOVQ	R12, SP
	// Back to Go world, set special registers.
	// The g register (R14) is preserved in C.
	XORPS	X15, X15
	RET

// C->Go callback thunk that allows to call runtime·racesymbolize from C code.
// Direct Go->C race call has only switched SP, finish g->g0 switch by setting correct g.

	// takes no arguments and doesn't return any values so
	// there's no need to handle that. Clear R14 so that there's
	// a bad value in there, in case needm tries to use it.
	XORPS	X15, X15
	XORQ    R14, R14
	MOVQ	$runtime·needAndBindM<ABIInternal>(SB), AX
	CALL	AX
	MOVQ	$0, savedm-8(SP)
	get_tls(CX)
	MOVQ	g(CX), BX
	MOVQ	g_m(BX), BX

	XORPD X11, X11                          // 66450f57db
	XORPS (BX), X2                          // 0f5713
	XORPS (R11), X2                         // 410f5713
	XORPS X2, X2                            // 0f57d2
	XORPS X11, X2                           // 410f57d3
	XORPS (BX), X11                         // 440f571b
	XORPS (R11), X11                        // 450f571b
	XORPS X2, X11                           // 440f57da

	XBEGIN:          "XBEGIN",
	XCHG:            "XCHG",
	XEND:            "XEND",
	XGETBV:          "XGETBV",
	XLATB:           "XLATB",
	XOR:             "XOR",
	XORPD:           "XORPD",
	XORPS:           "XORPS",
	XRSTOR:          "XRSTOR",
	XRSTOR64:        "XRSTOR64",
	XRSTORS:         "XRSTORS",
	XRSTORS64:       "XRSTORS64",
	XSAVE:           "XSAVE",
	XSAVE64:         "XSAVE64",