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// Copyright 2016 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.
// Based on dim_amd64.s
#include "textflag.h"
#define PosInf 0x7FF0000000000000
#define NaN 0x7FF8000000000001
#define NegInf 0xFFF0000000000000
// func ·Max(x, y float64) float64
TEXT ·archMax(SB),NOSPLIT,$0
// +Inf special cases
MOVD $PosInf, R4
MOVD x+0(FP), R8
CMPUBEQ R4, R8, isPosInf
MOVD y+8(FP), R9
CMPUBEQ R4, R9, isPosInf
// NaN special cases
MOVD $~(1<<63), R5 // bit mask
MOVD $PosInf, R4
MOVD R8, R2
AND R5, R2 // x = |x|
CMPUBLT R4, R2, isMaxNaN
MOVD R9, R3
AND R5, R3 // y = |y|
CMPUBLT R4, R3, isMaxNaN
// ±0 special cases
OR R3, R2
BEQ isMaxZero
FMOVD x+0(FP), F1
FMOVD y+8(FP), F2
FCMPU F2, F1
BGT +3(PC)
FMOVD F1, ret+16(FP)
RET
FMOVD F2, ret+16(FP)
RET
isMaxNaN: // return NaN
MOVD $NaN, R4
isPosInf: // return +Inf
MOVD R4, ret+16(FP)
RET
isMaxZero:
MOVD $(1<<63), R4 // -0.0
CMPUBEQ R4, R8, +3(PC)
MOVD R8, ret+16(FP) // return 0
RET
MOVD R9, ret+16(FP) // return other 0
RET
// func archMin(x, y float64) float64
TEXT ·archMin(SB),NOSPLIT,$0
// -Inf special cases
MOVD $NegInf, R4
MOVD x+0(FP), R8
CMPUBEQ R4, R8, isNegInf
MOVD y+8(FP), R9
CMPUBEQ R4, R9, isNegInf
// NaN special cases
MOVD $~(1<<63), R5
MOVD $PosInf, R4
MOVD R8, R2
AND R5, R2 // x = |x|
CMPUBLT R4, R2, isMinNaN
MOVD R9, R3
AND R5, R3 // y = |y|
CMPUBLT R4, R3, isMinNaN
// ±0 special cases
OR R3, R2
BEQ isMinZero
FMOVD x+0(FP), F1
FMOVD y+8(FP), F2
FCMPU F2, F1
BLT +3(PC)
FMOVD F1, ret+16(FP)
RET
FMOVD F2, ret+16(FP)
RET
isMinNaN: // return NaN
MOVD $NaN, R4
isNegInf: // return -Inf
MOVD R4, ret+16(FP)
RET
isMinZero:
MOVD $(1<<63), R4 // -0.0
CMPUBEQ R4, R8, +3(PC)
MOVD R9, ret+16(FP) // return other 0
RET
MOVD R8, ret+16(FP) // return -0
RET
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