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/* Machine-specific calling sequence for `mcount' profiling function. x86-64 version.
Copyright (C) 2002-2020 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
<https://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>
ENTRY(_mcount)
/* Allocate space for 7 registers. */
subq $56,%rsp
cfi_adjust_cfa_offset (56)
movq %rax,(%rsp)
cfi_rel_offset (rax, 0)
movq %rcx,8(%rsp)
cfi_rel_offset (rcx, 8)
movq %rdx,16(%rsp)
cfi_rel_offset (rdx, 16)
movq %rsi,24(%rsp)
cfi_rel_offset (rsi, 24)
movq %rdi,32(%rsp)
cfi_rel_offset (rdi, 32)
movq %r8,40(%rsp)
cfi_rel_offset (r8, 40)
movq %r9,48(%rsp)
cfi_rel_offset (r9, 48)
/* 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
call C_SYMBOL_NAME(__mcount_internal)
/* Pop the saved registers. Please note that `mcount' has no
return value. */
movq 48(%rsp),%r9
cfi_restore (r9)
movq 40(%rsp),%r8
cfi_restore (r8)
movq 32(%rsp),%rdi
cfi_restore (rdi)
movq 24(%rsp),%rsi
cfi_restore (rsi)
movq 16(%rsp),%rdx
cfi_restore (rdx)
movq 8(%rsp),%rcx
cfi_restore (rcx)
movq (%rsp),%rax
cfi_restore (rax)
addq $56,%rsp
cfi_adjust_cfa_offset (-56)
ret
END(_mcount)
#undef mcount
weak_alias (_mcount, mcount)
/* __fentry__ is different from _mcount in that it is called before
function prolog. This means (among other things) that it has non-standard
stack alignment on entry: (%RSP & 0xF) == 0. */
ENTRY(__fentry__)
/* Allocate space for 7 registers
(+8 bytes for proper stack alignment). */
subq $64,%rsp
cfi_adjust_cfa_offset (64)
movq %rax,(%rsp)
cfi_rel_offset (rax, 0)
movq %rcx,8(%rsp)
cfi_rel_offset (rcx, 8)
movq %rdx,16(%rsp)
cfi_rel_offset (rdx, 16)
movq %rsi,24(%rsp)
cfi_rel_offset (rsi, 24)
movq %rdi,32(%rsp)
cfi_rel_offset (rdi, 32)
movq %r8,40(%rsp)
cfi_rel_offset (r8, 40)
movq %r9,48(%rsp)
cfi_rel_offset (r9, 48)
/* 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
call C_SYMBOL_NAME(__mcount_internal)
/* Pop the saved registers. Please note that `__fentry__' has no
return value. */
movq 48(%rsp),%r9
cfi_restore (r9)
movq 40(%rsp),%r8
cfi_restore (r8)
movq 32(%rsp),%rdi
cfi_restore (rdi)
movq 24(%rsp),%rsi
cfi_restore (rsi)
movq 16(%rsp),%rdx
cfi_restore (rdx)
movq 8(%rsp),%rcx
cfi_restore (rcx)
movq (%rsp),%rax
cfi_restore (rax)
addq $64,%rsp
cfi_adjust_cfa_offset (-64)
ret
END(__fentry__)
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