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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.
#include "textflag.h"
// func Frexp(f float64) (frac float64, exp int)
TEXT ·Frexp(SB),NOSPLIT,$0
FMOVD f+0(FP), F0 // F0=f
FXAM
FSTSW AX
SAHF
JNP nan_zero_inf
JCS nan_zero_inf
FXTRACT // F0=f (0<=f<1), F1=e
FMULD $(0.5), F0 // F0=f (0.5<=f<1), F1=e
FMOVDP F0, frac+8(FP) // F0=e
FLD1 // F0=1, F1=e
FADDDP F0, F1 // F0=e+1
FMOVLP F0, exp+16(FP) // (int=int32)
RET
nan_zero_inf:
FMOVDP F0, frac+8(FP) // F0=e
MOVL $0, exp+16(FP) // exp=0
RET
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