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// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// func Modf(x float64) (int float64, frac float64)
TEXT ·Modf(SB),7,$0
FMOVD x+0(FP), F0 // F0=x
FMOVD F0, F1 // F0=x, F1=x
FSTCW -2(SP) // save old Control Word
ORW $0x0c00, AX // Rounding Control set to truncate
MOVW AX, -4(SP) // store new Control Word
FLDCW -4(SP) // load new Control Word
FRNDINT // F0=trunc(x), F1=x
FLDCW -2(SP) // load old Control Word
FSUBD F0, F1 // F0=trunc(x), F1=x-trunc(x)
FMOVDP F0, i+8(FP) // F0=x-trunc(x)
FMOVDP F0, f+16(FP)