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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 Ceil(x float64) float64
TEXT ·Ceil(SB),NOSPLIT,$0
FMOVD x+0(FP), F0 // F0=x
FSTCW -2(SP) // save old Control Word
MOVW -2(SP), AX
ANDW $0xf3ff, AX
ORW $0x0800, AX // Rounding Control set to +Inf
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 Floor(x float64) float64
TEXT ·Floor(SB),NOSPLIT,$0
FMOVD x+0(FP), F0 // F0=x
FSTCW -2(SP) // save old Control Word
MOVW -2(SP), AX
ANDW $0xf3ff, AX
ORW $0x0400, AX // Rounding Control set to -Inf
MOVW AX, -4(SP) // store new Control Word
FLDCW -4(SP) // load new Control Word
FRNDINT // F0=Floor(x)
FLDCW -2(SP) // load old Control Word
FMOVDP F0, ret+8(FP)
RET
// func Trunc(x float64) float64
TEXT ·Trunc(SB),NOSPLIT,$0
FMOVD x+0(FP), F0 // F0=x
FSTCW -2(SP) // save old Control Word
MOVW -2(SP), AX
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)
FLDCW -2(SP) // load old Control Word
FMOVDP F0, ret+8(FP)
RET
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