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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 ·Max(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 Min(x, y float64) float64
| TEXT ·Min(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
|
|
