1 // Copyright 2010 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 #include "textflag.h" 6 7 // func Ceil(x float64) float64 8 TEXT Ceil(SB),NOSPLIT,$0 9 FMOVD x+0(FP), F0 // F0=x 10 FSTCW -2(SP) // save old Control Word 11 MOVW -2(SP), AX 12 ANDW $0xf3ff, AX 13 ORW $0x0800, AX // Rounding Control set to +Inf 14 MOVW AX, -4(SP) // store new Control Word 15 FLDCW -4(SP) // load new Control Word 16 FRNDINT // F0=Ceil(x) 17 FLDCW -2(SP) // load old Control Word 18 FMOVDP F0, ret+8(FP) 19 RET 20 21 // func Floor(x float64) float64 22 TEXT Floor(SB),NOSPLIT,$0 23 FMOVD x+0(FP), F0 // F0=x 24 FSTCW -2(SP) // save old Control Word 25 MOVW -2(SP), AX 26 ANDW $0xf3ff, AX 27 ORW $0x0400, AX // Rounding Control set to -Inf 28 MOVW AX, -4(SP) // store new Control Word 29 FLDCW -4(SP) // load new Control Word 30 FRNDINT // F0=Floor(x) 31 FLDCW -2(SP) // load old Control Word 32 FMOVDP F0, ret+8(FP) 33 RET 34 35 // func Trunc(x float64) float64 36 TEXT Trunc(SB),NOSPLIT,$0 37 FMOVD x+0(FP), F0 // F0=x 38 FSTCW -2(SP) // save old Control Word 39 MOVW -2(SP), AX 40 ORW $0x0c00, AX // Rounding Control set to truncate 41 MOVW AX, -4(SP) // store new Control Word 42 FLDCW -4(SP) // load new Control Word 43 FRNDINT // F0=Trunc(x) 44 FLDCW -2(SP) // load old Control Word 45 FMOVDP F0, ret+8(FP) 46 RET 47
