| | 1 | /* |
| | 2 | * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved. |
| | 3 | * |
| | 4 | * @APPLE_LICENSE_HEADER_START@ |
| | 5 | * |
| | 6 | * This file contains Original Code and/or Modifications of Original Code |
| | 7 | * as defined in and that are subject to the Apple Public Source License |
| | 8 | * Version 2.0 (the 'License'). You may not use this file except in |
| | 9 | * compliance with the License. Please obtain a copy of the License at |
| | 10 | * http://www.opensource.apple.com/apsl/ and read it before using this |
| | 11 | * file. |
| | 12 | * |
| | 13 | * The Original Code and all software distributed under the License are |
| | 14 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
| | 15 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
| | 16 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, |
| | 17 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. |
| | 18 | * Please see the License for the specific language governing rights and |
| | 19 | * limitations under the License. |
| | 20 | * |
| | 21 | * @APPLE_LICENSE_HEADER_END@ |
| | 22 | */ |
| | 23 | #if !defined(__ppc__) |
| | 24 | #include <stdint.h> |
| | 25 | #include <mach/clock.h> |
| | 26 | #include <mach/mach_time.h> |
| | 27 | |
| | 28 | extern mach_port_t clock_port; |
| | 29 | |
| | 30 | inline static uint64_t |
| | 31 | fast_get_nano_from_abs(int scale) |
| | 32 | { |
| | 33 | uint64_t value; |
| | 34 | asm ( |
| | 35 | "rdtsc \n\t" |
| | 36 | "movl %%edx,%%esi \n\t" |
| | 37 | "mull %%ecx \n\t" |
| | 38 | "movl %%edx,%%edi \n\t" |
| | 39 | "movl %%esi,%%eax \n\t" |
| | 40 | "mull %%ecx \n\t" |
| | 41 | "xorl %%ecx,%%ecx \n\t" |
| | 42 | "addl %%edi,%%eax \n\t" |
| | 43 | "adcl %%ecx,%%edx " |
| | 44 | : "=A"(value) : "c"(scale) : "%esi", "%edi"); |
| | 45 | return value; |
| | 46 | } |
| | 47 | |
| | 48 | uint64_t |
| | 49 | mach_absolute_time(void) { |
| | 50 | static int scale = 0; |
| | 51 | |
| | 52 | if (__builtin_expect(scale == 0, 0)) { |
| | 53 | mach_timebase_info_data_t info; |
| | 54 | mach_timebase_info(&info); |
| | 55 | scale = info.numer; |
| | 56 | } |
| | 57 | if (__builtin_expect(scale == 1, 0)) { |
| | 58 | mach_timespec_t now; |
| | 59 | (void)clock_get_time(clock_port, &now); |
| | 60 | return (uint64_t)now.tv_sec * NSEC_PER_SEC + now.tv_nsec; |
| | 61 | } |
| | 62 | return fast_get_nano_from_abs(scale); |
| | 63 | } |
| | 64 | #endif |
projects / apple / libc.git / blame_incremental