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 #define PosInf 0x7FF0000000000000 8 #define NaN 0x7FF8000000000001 9 #define NegInf 0xFFF0000000000000 10 11 // func Max(x, y float64) float64 12 TEXT Max(SB),NOSPLIT,$0 13 // +Inf special cases 14 MOVQ $PosInf, AX 15 MOVQ x+0(FP), R8 16 CMPQ AX, R8 17 JEQ isPosInf 18 MOVQ y+8(FP), R9 19 CMPQ AX, R9 20 JEQ isPosInf 21 // NaN special cases 22 MOVQ $~(1<<63), DX // bit mask 23 MOVQ $PosInf, AX 24 MOVQ R8, BX 25 ANDQ DX, BX // x = |x| 26 CMPQ AX, BX 27 JLT isMaxNaN 28 MOVQ R9, CX 29 ANDQ DX, CX // y = |y| 30 CMPQ AX, CX 31 JLT isMaxNaN 32 // 0 special cases 33 ORQ CX, BX 34 JEQ isMaxZero 35 36 MOVQ R8, X0 37 MOVQ R9, X1 38 MAXSD X1, X0 39 MOVSD X0, ret+16(FP) 40 RET 41 isMaxNaN: // return NaN 42 MOVQ $NaN, AX 43 isPosInf: // return +Inf 44 MOVQ AX, ret+16(FP) 45 RET 46 isMaxZero: 47 MOVQ $(1<<63), AX // -0.0 48 CMPQ AX, R8 49 JEQ +3(PC) 50 MOVQ R8, ret+16(FP) // return 0 51 RET 52 MOVQ R9, ret+16(FP) // return other 0 53 RET 54 55 // func Min(x, y float64) float64 56 TEXT Min(SB),NOSPLIT,$0 57 // -Inf special cases 58 MOVQ $NegInf, AX 59 MOVQ x+0(FP), R8 60 CMPQ AX, R8 61 JEQ isNegInf 62 MOVQ y+8(FP), R9 63 CMPQ AX, R9 64 JEQ isNegInf 65 // NaN special cases 66 MOVQ $~(1<<63), DX 67 MOVQ $PosInf, AX 68 MOVQ R8, BX 69 ANDQ DX, BX // x = |x| 70 CMPQ AX, BX 71 JLT isMinNaN 72 MOVQ R9, CX 73 ANDQ DX, CX // y = |y| 74 CMPQ AX, CX 75 JLT isMinNaN 76 // 0 special cases 77 ORQ CX, BX 78 JEQ isMinZero 79 80 MOVQ R8, X0 81 MOVQ R9, X1 82 MINSD X1, X0 83 MOVSD X0, ret+16(FP) 84 RET 85 isMinNaN: // return NaN 86 MOVQ $NaN, AX 87 isNegInf: // return -Inf 88 MOVQ AX, ret+16(FP) 89 RET 90 isMinZero: 91 MOVQ $(1<<63), AX // -0.0 92 CMPQ AX, R8 93 JEQ +3(PC) 94 MOVQ R9, ret+16(FP) // return other 0 95 RET 96 MOVQ R8, ret+16(FP) // return -0 97 RET 98 99
