| | 1 | /* |
| | 2 | * Copyright (c) 2006 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 | |
| | 24 | #include <stdbool.h> |
| | 25 | #include <stdint.h> |
| | 26 | #include <stdio.h> |
| | 27 | #include <sys/types.h> |
| | 28 | #include <unistd.h> |
| | 29 | #include <mach/mach.h> |
| | 30 | |
| | 31 | struct page |
| | 32 | { |
| | 33 | struct page* other; |
| | 34 | char pad[4096-sizeof(void*)]; |
| | 35 | }; |
| | 36 | |
| | 37 | |
| | 38 | struct page p1 = { &p1 }; |
| | 39 | struct page p2 = { &p1 }; |
| | 40 | struct page p3 = { &p1 }; |
| | 41 | struct page p4 = { &p1 }; |
| | 42 | struct page p5 = { &p1 }; |
| | 43 | struct page p6 = { &p1 }; |
| | 44 | struct page p7 = { &p1 }; |
| | 45 | struct page p8 = { &p1 }; |
| | 46 | struct page p9 = { &p1 }; |
| | 47 | struct page p10 = { &p1 }; |
| | 48 | |
| | 49 | // |
| | 50 | // This dylib has 10 pages of data and each page will be adjusted |
| | 51 | // by dyld if this dylib is not loaded at its preferred address. |
| | 52 | // |
| | 53 | bool checkRebasing() |
| | 54 | { |
| | 55 | int dirtyPageCount = 0; |
| | 56 | vm_address_t start = (((uintptr_t)&p1) + 4095) & (-4096); |
| | 57 | vm_address_t end = (((uintptr_t)&p10) + 4095) & (-4096); |
| | 58 | task_port_t task; |
| | 59 | task_for_pid(mach_task_self(), getpid(), &task); |
| | 60 | |
| | 61 | for (vm_address_t addr = start; addr < end; addr += 4096) { |
| | 62 | integer_t disposition = 0; |
| | 63 | integer_t ref_count = 0; |
| | 64 | vm_map_page_query(task, start, &disposition, &ref_count); |
| | 65 | if ( disposition & VM_PAGE_QUERY_PAGE_DIRTY ) |
| | 66 | ++dirtyPageCount; |
| | 67 | } |
| | 68 | |
| | 69 | //fprintf(stderr, "dirtyPageCount=%d\n", dirtyPageCount); |
| | 70 | |
| | 71 | // if there are too many dirty pages, then dyld is inefficient |
| | 72 | return ( dirtyPageCount < 2 ); |
| | 73 | } |
| | 74 | |
| | 75 | |
| | 76 | |
| | 77 | |
| | 78 | |
projects / apple / dyld.git / blame_incremental