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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 | /* * Copyright (c) 2003-2007 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ #include <sys/appleapiopts.h> #include <machine/cpu_capabilities.h> #define NSEC_PER_SEC 1000*1000*1000 #define NSEC_PER_USEC 1000 #if defined(__i386__) .align 4 .globl ___commpage_gettimeofday ___commpage_gettimeofday: push %ebp mov %esp,%ebp push %esi push %ebx 0: movl _COMM_PAGE_GTOD_GENERATION,%esi /* get generation (0 if disabled) */ testl %esi,%esi /* disabled? */ jz 4f call _mach_absolute_time /* get nanotime in %edx:%eax */ sub _COMM_PAGE_GTOD_NS_BASE,%eax sbb _COMM_PAGE_GTOD_NS_BASE+4,%edx mov _COMM_PAGE_GTOD_SEC_BASE,%ebx /* load all the data before checking generation */ mov $ NSEC_PER_SEC,%ecx cmpl _COMM_PAGE_GTOD_GENERATION,%esi /* has time data changed out from under us? */ jne 0b div %ecx add %eax,%ebx mov $ NSEC_PER_USEC,%ecx mov %edx,%eax xor %edx,%edx div %ecx mov 8(%ebp),%ecx mov %ebx,(%ecx) mov %eax,4(%ecx) xor %eax,%eax 3: pop %ebx pop %esi pop %ebp ret 4: /* fail */ movl $1,%eax jmp 3b #elif defined(__x86_64__) .align 4, 0x90 .globl ___commpage_gettimeofday ___commpage_gettimeofday: // %rdi = ptr to timeval pushq %rbp // set up a frame for backtraces pushq %r12 // push callee-saved registers we want to use pushq %r13 pushq %r14 subq $8, %rsp movq %rsp,%rbp movq %rdi,%r12 // save ptr to timeval movq $(_COMM_PAGE_TIME_DATA_START),%r13 0: movl _GTOD_GENERATION(%r13),%r14d // get generation (0 if disabled) testl %r14d,%r14d // disabled? jz 4f call _mach_absolute_time // get %rax <- nanotime() movl _GTOD_SEC_BASE(%r13),%r8d // get _COMM_PAGE_TIMESTAMP subq _GTOD_NS_BASE(%r13),%rax // generate nanoseconds since timestamp cmpl _GTOD_GENERATION(%r13),%r14d // has data changed out from under us? jne 0b movl $ NSEC_PER_SEC,%ecx movq %rax,%rdx shrq $32,%rdx // get high half of delta in %edx divl %ecx // %eax <- seconds since timestamp, %edx <- nanoseconds addl %eax,%r8d // add seconds elapsed to timestamp seconds movl $ NSEC_PER_USEC,%ecx movl %edx,%eax xorl %edx,%edx divl %ecx // divide residual ns by 1000 to get residual us in %eax movq %r8,(%r12) // store 64-bit seconds into timeval movl %eax,8(%r12) // store 32-bit useconds into timeval xorl %eax,%eax // return 0 for success 3: addq $8, %rsp popq %r14 popq %r13 popq %r12 popq %rbp ret 4: // fail movl $1,%eax jmp 3b #endif |