MOVW    AX, -4(SP)   // store new Control Word
	FLDCW   -4(SP)       // load new Control Word
	FRNDINT              // F0=Ceil(x)
	FLDCW   -2(SP)       // load old Control Word
	FMOVDP  F0, ret+8(FP)
	RET

// func archFloor(x float64) float64
TEXT ·archFloor(SB),NOSPLIT,$0
	FMOVD   x+0(FP), F0  // F0=x
	FSTCW   -2(SP)       // save old Control Word
	MOVW    -2(SP), AX
	ANDW    $0xf3ff, AX

	FLD1                 // F0=1, F1=q*q, F2=p
	FADDDP  F0, F1       // F0=1+q*q, F1=p
	FSQRT                // F0=sqrt(1+q*q), F1=p
	FMULDP  F0, F1       // F0=p*sqrt(1+q*q)
	FMOVDP  F0, ret+16(FP)
	RET
	FMOVDP  F0, F1       // F0=0
	FMOVDP  F0, ret+16(FP)
	RET
not_finite:
// test bits for -Inf or +Inf
	MOVL    p_hi+4(FP), AX  // high word p
	ORL     p_lo+0(FP), AX  // low word p
	ANDL    $0x7fffffff, AX

	"FFREE",
	"FINCSTP",
	"FINIT",
	"FLD1",
	"FLDCW",
	"FLDENV",
	"FLDL2E",
	"FLDL2T",
	"FLDLG2",
	"FLDLN2",
	"FLDPI",
	"FLDZ",
	"FMOVB",
	"FMOVBP",
	"FMOVD",
	"FMOVDP",
	"FMOVF",
	"FMOVFP",
	"FMOVL",
	"FMOVLP",
	"FMOVV",
	"FMOVVP",
	"FMOVW",
	"FMOVWP",
	"FMOVX",
	"FMOVXP",
	"FMULD",
	"FMULDP",
	"FMULF",
	"FMULL",
	"FMULW",

	case "amd64.LEAQ":
		dst = 8
		addr = true
	default:
		switch fn.arch.name {
		case "386", "amd64":
			if strings.HasPrefix(op, "F") && (strings.HasSuffix(op, "D") || strings.HasSuffix(op, "DP")) {
				// FMOVDP, FXCHD, etc
				src = 8
				break
			}
			if strings.HasPrefix(op, "P") && strings.HasSuffix(op, "RD") {
				// PINSRD, PEXTRD, etc
				src = 4
				break
			}

	MOVL	AX, moduledata_next(DX)
	MOVL	AX, runtime·lastmoduledatap(SB)
	RET

TEXT runtime·uint32tofloat64(SB),NOSPLIT,$8-12
	MOVL	a+0(FP), AX
	MOVL	AX, 0(SP)
	MOVL	$0, 4(SP)
	FMOVV	0(SP), F0
	FMOVDP	F0, ret+4(FP)
	RET

TEXT runtime·float64touint32(SB),NOSPLIT,$12-12
	FMOVD	a+0(FP), F0
	FSTCW	0(SP)
	FLDCW	runtime·controlWord64trunc(SB)
	FMOVVP	F0, 4(SP)
	FLDCW	0(SP)
	MOVL	4(SP), AX