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/* Machine-specific calling sequence for `mcount' profiling function. x86-64 version.
Copyright (C) 2002-2012 Free Software Foundation, Inc.
Contributed by Andreas Jaeger <aj@suse.de>.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
/* Assembly stub to invoke _mcount(). Compiler generated code calls
this stub after executing a function's prologue and without saving any
registers. It is therefore necessary to preserve %rcx, %rdx, %rsi, %rdi,
%r8, %r9 as they may contain function arguments. */
#include <sysdep.h>
.globl C_SYMBOL_NAME(_mcount)
ASM_TYPE_DIRECTIVE(C_SYMBOL_NAME(_mcount), @function)
.align ALIGNARG(4)
C_LABEL(_mcount)
/* Allocate space for 7 registers. */
subq $56,%rsp
movq %rax,(%rsp)
movq %rcx,8(%rsp)
movq %rdx,16(%rsp)
movq %rsi,24(%rsp)
movq %rdi,32(%rsp)
movq %r8,40(%rsp)
movq %r9,48(%rsp)
/* Setup parameter for __mcount_internal. */
/* selfpc is the return address on the stack. */
movq 56(%rsp),%rsi
/* Get frompc via the frame pointer. */
movq 8(%rbp),%rdi
#ifdef PIC
call C_SYMBOL_NAME(__mcount_internal)@PLT
#else
call C_SYMBOL_NAME(__mcount_internal)
#endif
/* Pop the saved registers. Please note that `mcount' has no
return value. */
movq 48(%rsp),%r9
movq 40(%rsp),%r8
movq 32(%rsp),%rdi
movq 24(%rsp),%rsi
movq 16(%rsp),%rdx
movq 8(%rsp),%rcx
movq (%rsp),%rax
addq $56,%rsp
ret
ASM_SIZE_DIRECTIVE(C_SYMBOL_NAME(_mcount))
#undef mcount
weak_alias (_mcount, mcount)
.globl C_SYMBOL_NAME(__fentry__)
ASM_TYPE_DIRECTIVE(C_SYMBOL_NAME(__fentry__), @function)
.align ALIGNARG(4)
C_LABEL(__fentry__)
/* Allocate space for 7 registers. */
subq $64,%rsp
movq %rax,(%rsp)
movq %rcx,8(%rsp)
movq %rdx,16(%rsp)
movq %rsi,24(%rsp)
movq %rdi,32(%rsp)
movq %r8,40(%rsp)
movq %r9,48(%rsp)
/* Setup parameter for __mcount_internal. */
/* selfpc is the return address on the stack. */
movq 64(%rsp),%rsi
/* caller is the return address above it */
movq 72(%rsp),%rdi
#ifdef PIC
call C_SYMBOL_NAME(__mcount_internal)@PLT
#else
call C_SYMBOL_NAME(__mcount_internal)
#endif
/* Pop the saved registers. Please note that `__fentry__' has no
return value. */
movq 48(%rsp),%r9
movq 40(%rsp),%r8
movq 32(%rsp),%rdi
movq 24(%rsp),%rsi
movq 16(%rsp),%rdx
movq 8(%rsp),%rcx
movq (%rsp),%rax
addq $64,%rsp
ret
ASM_SIZE_DIRECTIVE(C_SYMBOL_NAME(__fentry__))
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