1 // Copyright 2015 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 // bool Cas(int32 *val, int32 old, int32 new) 8 // Atomically: 9 // if(*val == old){ 10 // *val = new; 11 // return 1; 12 // }else 13 // return 0; 14 TEXT runtimeinternalatomicCas(SB), NOSPLIT, $0-13 15 MOVL ptr+0(FP), BX 16 MOVL old+4(FP), AX 17 MOVL new+8(FP), CX 18 LOCK 19 CMPXCHGL CX, 0(BX) 20 SETEQ ret+12(FP) 21 RET 22 23 TEXT runtimeinternalatomicCasuintptr(SB), NOSPLIT, $0-13 24 JMP runtimeinternalatomicCas(SB) 25 26 TEXT runtimeinternalatomicLoaduintptr(SB), NOSPLIT, $0-8 27 JMP runtimeinternalatomicLoad(SB) 28 29 TEXT runtimeinternalatomicLoaduint(SB), NOSPLIT, $0-8 30 JMP runtimeinternalatomicLoad(SB) 31 32 TEXT runtimeinternalatomicStoreuintptr(SB), NOSPLIT, $0-8 33 JMP runtimeinternalatomicStore(SB) 34 35 TEXT runtimeinternalatomicXadduintptr(SB), NOSPLIT, $0-12 36 JMP runtimeinternalatomicXadd(SB) 37 38 TEXT runtimeinternalatomicLoadint64(SB), NOSPLIT, $0-12 39 JMP runtimeinternalatomicLoad64(SB) 40 41 TEXT runtimeinternalatomicXaddint64(SB), NOSPLIT, $0-20 42 JMP runtimeinternalatomicXadd64(SB) 43 44 45 // bool runtimeinternalatomicCas64(uint64 *val, uint64 old, uint64 new) 46 // Atomically: 47 // if(*val == *old){ 48 // *val = new; 49 // return 1; 50 // } else { 51 // return 0; 52 // } 53 TEXT runtimeinternalatomicCas64(SB), NOSPLIT, $0-21 54 MOVL ptr+0(FP), BP 55 TESTL $7, BP 56 JZ 2(PC) 57 MOVL 0, BP // crash with nil ptr deref 58 MOVL old_lo+4(FP), AX 59 MOVL old_hi+8(FP), DX 60 MOVL new_lo+12(FP), BX 61 MOVL new_hi+16(FP), CX 62 LOCK 63 CMPXCHG8B 0(BP) 64 SETEQ ret+20(FP) 65 RET 66 67 // bool Casp1(void **p, void *old, void *new) 68 // Atomically: 69 // if(*p == old){ 70 // *p = new; 71 // return 1; 72 // }else 73 // return 0; 74 TEXT runtimeinternalatomicCasp1(SB), NOSPLIT, $0-13 75 MOVL ptr+0(FP), BX 76 MOVL old+4(FP), AX 77 MOVL new+8(FP), CX 78 LOCK 79 CMPXCHGL CX, 0(BX) 80 SETEQ ret+12(FP) 81 RET 82 83 // uint32 Xadd(uint32 volatile *val, int32 delta) 84 // Atomically: 85 // *val += delta; 86 // return *val; 87 TEXT runtimeinternalatomicXadd(SB), NOSPLIT, $0-12 88 MOVL ptr+0(FP), BX 89 MOVL delta+4(FP), AX 90 MOVL AX, CX 91 LOCK 92 XADDL AX, 0(BX) 93 ADDL CX, AX 94 MOVL AX, ret+8(FP) 95 RET 96 97 TEXT runtimeinternalatomicXchg(SB), NOSPLIT, $0-12 98 MOVL ptr+0(FP), BX 99 MOVL new+4(FP), AX 100 XCHGL AX, 0(BX) 101 MOVL AX, ret+8(FP) 102 RET 103 104 TEXT runtimeinternalatomicXchguintptr(SB), NOSPLIT, $0-12 105 JMP runtimeinternalatomicXchg(SB) 106 107 108 TEXT runtimeinternalatomicStorepNoWB(SB), NOSPLIT, $0-8 109 MOVL ptr+0(FP), BX 110 MOVL val+4(FP), AX 111 XCHGL AX, 0(BX) 112 RET 113 114 TEXT runtimeinternalatomicStore(SB), NOSPLIT, $0-8 115 MOVL ptr+0(FP), BX 116 MOVL val+4(FP), AX 117 XCHGL AX, 0(BX) 118 RET 119 120 // uint64 atomicload64(uint64 volatile* addr); 121 TEXT runtimeinternalatomicLoad64(SB), NOSPLIT, $0-12 122 MOVL ptr+0(FP), AX 123 TESTL $7, AX 124 JZ 2(PC) 125 MOVL 0, AX // crash with nil ptr deref 126 LEAL ret_lo+4(FP), BX 127 // MOVQ (%EAX), %MM0 128 BYTE $0x0f; BYTE $0x6f; BYTE $0x00 129 // MOVQ %MM0, 0(%EBX) 130 BYTE $0x0f; BYTE $0x7f; BYTE $0x03 131 // EMMS 132 BYTE $0x0F; BYTE $0x77 133 RET 134 135 // void runtimeinternalatomicStore64(uint64 volatile* addr, uint64 v); 136 TEXT runtimeinternalatomicStore64(SB), NOSPLIT, $0-12 137 MOVL ptr+0(FP), AX 138 TESTL $7, AX 139 JZ 2(PC) 140 MOVL 0, AX // crash with nil ptr deref 141 // MOVQ and EMMS were introduced on the Pentium MMX. 142 // MOVQ 0x8(%ESP), %MM0 143 BYTE $0x0f; BYTE $0x6f; BYTE $0x44; BYTE $0x24; BYTE $0x08 144 // MOVQ %MM0, (%EAX) 145 BYTE $0x0f; BYTE $0x7f; BYTE $0x00 146 // EMMS 147 BYTE $0x0F; BYTE $0x77 148 // This is essentially a no-op, but it provides required memory fencing. 149 // It can be replaced with MFENCE, but MFENCE was introduced only on the Pentium4 (SSE2). 150 MOVL $0, AX 151 LOCK 152 XADDL AX, (SP) 153 RET 154 155 // void runtimeinternalatomicOr8(byte volatile*, byte); 156 TEXT runtimeinternalatomicOr8(SB), NOSPLIT, $0-5 157 MOVL ptr+0(FP), AX 158 MOVB val+4(FP), BX 159 LOCK 160 ORB BX, (AX) 161 RET 162 163 // void runtimeinternalatomicAnd8(byte volatile*, byte); 164 TEXT runtimeinternalatomicAnd8(SB), NOSPLIT, $0-5 165 MOVL ptr+0(FP), AX 166 MOVB val+4(FP), BX 167 LOCK 168 ANDB BX, (AX) 169 RET 170
