| | 1 | /* |
| | 2 | * Copyright (c) 2003 Apple Computer, Inc. All rights reserved. |
| | 3 | * |
| | 4 | * @APPLE_OSREFERENCE_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. The rights granted to you under the License |
| | 10 | * may not be used to create, or enable the creation or redistribution of, |
| | 11 | * unlawful or unlicensed copies of an Apple operating system, or to |
| | 12 | * circumvent, violate, or enable the circumvention or violation of, any |
| | 13 | * terms of an Apple operating system software license agreement. |
| | 14 | * |
| | 15 | * Please obtain a copy of the License at |
| | 16 | * http://www.opensource.apple.com/apsl/ and read it before using this file. |
| | 17 | * |
| | 18 | * The Original Code and all software distributed under the License are |
| | 19 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
| | 20 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
| | 21 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, |
| | 22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. |
| | 23 | * Please see the License for the specific language governing rights and |
| | 24 | * limitations under the License. |
| | 25 | * |
| | 26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ |
| | 27 | */ |
| | 28 | |
| | 29 | #define __NO_UNDERSCORES__ |
| | 30 | #include <i386/asm.h> |
| | 31 | #include <assym.s> |
| | 32 | |
| | 33 | Entry(mcount) |
| | 34 | pushq %rbp // setup mcount's frame |
| | 35 | movq %rsp,%rbp |
| | 36 | pushq %rax // save %eax |
| | 37 | pushf // save interrupt state |
| | 38 | cli // disable interrupts |
| | 39 | |
| | 40 | // |
| | 41 | // Check that this cpu is ready. |
| | 42 | // This delays the start of mcounting until a cpu is really prepared. |
| | 43 | // |
| | 44 | mov %gs,%ax |
| | 45 | test %ax,%ax |
| | 46 | jz 1f |
| | 47 | |
| | 48 | movl %gs:CPU_RUNNING,%eax |
| | 49 | testl %eax,%eax |
| | 50 | jz 1f |
| | 51 | |
| | 52 | // |
| | 53 | // Test for recursion as indicated by a per-cpu flag. |
| | 54 | // Skip if nested, otherwise set the flag and call the C mount(). |
| | 55 | // |
| | 56 | movl %gs:CPU_MCOUNT_OFF,%eax |
| | 57 | testl %eax,%eax // test for recursion |
| | 58 | jnz 1f |
| | 59 | |
| | 60 | incl %gs:CPU_MCOUNT_OFF // set recursion flag |
| | 61 | |
| | 62 | movq (%rbp),%rax // frame pointer of mcount's caller |
| | 63 | pushq %rdi |
| | 64 | pushq %rsi |
| | 65 | pushq %rdx |
| | 66 | pushq %rcx |
| | 67 | pushq %r8 |
| | 68 | pushq %r9 |
| | 69 | movq 8(%rax),%rdi // mcount's caller's return address |
| | 70 | movq 8(%rbp),%rsi // push selfpc parameter for mcount() |
| | 71 | |
| | 72 | call _mcount // call the C mcount |
| | 73 | |
| | 74 | popq %r9 |
| | 75 | popq %r8 |
| | 76 | popq %rcx |
| | 77 | popq %rdx |
| | 78 | popq %rsi |
| | 79 | popq %rdi |
| | 80 | |
| | 81 | decl %gs:CPU_MCOUNT_OFF // turn off recursion flag |
| | 82 | 1: |
| | 83 | popf // restore interrupt state |
| | 84 | popq %rax |
| | 85 | movq %rbp,%rsp // tear down mcount's frame |
| | 86 | popq %rbp |
| | 87 | ret |
projects / apple / xnu.git / blame_incremental