sys/amd64/include/profile.h

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1992, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      @(#)profile.h   8.1 (Berkeley) 6/11/93
  32  * $FreeBSD$
  33  */
  34
  35 #ifndef _MACHINE_PROFILE_H_
  36 #define _MACHINE_PROFILE_H_
  37
  38 #ifndef _KERNEL
  39
  40 #include <sys/cdefs.h>
  41
  42 #define FUNCTION_ALIGNMENT      4
  43
  44 #define _MCOUNT_DECL \
  45 static void _mcount(uintfptr_t frompc, uintfptr_t selfpc) __used; \
  46 static void _mcount
  47
  48 #define MCOUNT __asm("                  \n\
  49         .text                           \n\
  50         .p2align 4,0x90                 \n\
  51         .globl  .mcount                 \n\
  52         .type   .mcount,@function       \n\
  53 .mcount:                                \n\
  54         pushq   %rdi                    \n\
  55         pushq   %rsi                    \n\
  56         pushq   %rdx                    \n\
  57         pushq   %rcx                    \n\
  58         pushq   %r8                     \n\
  59         pushq   %r9                     \n\
  60         pushq   %rax                    \n\
  61         movq    8(%rbp),%rdi            \n\
  62         movq    7*8(%rsp),%rsi          \n\
  63         call    _mcount                 \n\
  64         popq    %rax                    \n\
  65         popq    %r9                     \n\
  66         popq    %r8                     \n\
  67         popq    %rcx                    \n\
  68         popq    %rdx                    \n\
  69         popq    %rsi                    \n\
  70         popq    %rdi                    \n\
  71         ret                             \n\
  72         .size   .mcount, . - .mcount");
  73 #if 0
  74 /*
  75  * We could use this, except it doesn't preserve the registers that were
  76  * being passed with arguments to the function that we were inserted
  77  * into.  I've left it here as documentation of what the code above is
  78  * supposed to do.
  79  */
  80 #define MCOUNT                                                          \
  81 void                                                                    \
  82 mcount()                                                                \
  83 {                                                                       \
  84         uintfptr_t selfpc, frompc;                                      \
  85         /*                                                              \
  86          * Find the return address for mcount,                          \
  87          * and the return address for mcount's caller.                  \
  88          *                                                              \
  89          * selfpc = pc pushed by call to mcount                         \
  90          */                                                             \
  91         __asm("movq 8(%%rbp),%0" : "=r" (selfpc));                      \
  92         /*                                                              \
  93          * frompc = pc pushed by call to mcount's caller.               \
  94          * The caller's stack frame has already been built, so %rbp is  \
  95          * the caller's frame pointer.  The caller's raddr is in the    \
  96          * caller's frame following the caller's caller's frame pointer.\
  97          */                                                             \
  98         __asm("movq (%%rbp),%0" : "=r" (frompc));                       \
  99         frompc = ((uintfptr_t *)frompc)[1];                             \
 100         _mcount(frompc, selfpc);                                        \
 101 }
 102 #endif
 103
 104 typedef u_long  uintfptr_t;
 105
 106 /*
 107  * An unsigned integral type that can hold non-negative difference between
 108  * function pointers.
 109  */
 110 typedef u_long  fptrdiff_t;
 111
 112 __BEGIN_DECLS
 113 void    mcount(void) __asm(".mcount");
 114 __END_DECLS
 115
 116 #endif /* !_KERNEL */
 117
 118 #endif /* !_MACHINE_PROFILE_H_ */