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/* PowerPC-specific implementation of profiling support.
Copyright (C) 1997-2021 Free Software Foundation, Inc.
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/>. */
/* This would be bad. */
#ifdef PROF
#undef PROF
#endif
#include <sysdep.h>
/* We do profiling as described in the SYSV ELF ABI, except that glibc
_mcount manages its own counters. The caller has put the address the
caller will return to in the usual place on the stack, 4(r1). _mcount
is responsible for ensuring that when it returns no argument-passing
registers are disturbed, and that the LR is set back to (what the
caller sees as) 4(r1).
This is intended so that the following code can be inserted at the
front of any routine without changing the routine:
.data
mflr r0
stw r0,4(r1)
bl _mcount
*/
ENTRY(_mcount)
#if defined PIC && !defined SHARED
# define CALLER_LR_OFFSET 68
stwu r1,-64(r1)
cfi_adjust_cfa_offset (64)
stw r30, 48(r1)
cfi_rel_offset (r30, 48)
#else
# define CALLER_LR_OFFSET 52
stwu r1,-48(r1)
cfi_adjust_cfa_offset (48)
#endif
/* We need to save the parameter-passing registers. */
stw r3, 12(r1)
stw r4, 16(r1)
stw r5, 20(r1)
stw r6, 24(r1)
mflr r4
#if defined PIC && !defined SHARED
bcl 20,31,0f
0:
mflr r30
addis r30, r30, _GLOBAL_OFFSET_TABLE_-0b@ha
addi r30, r30, _GLOBAL_OFFSET_TABLE_-0b@l
#endif
lwz r3, CALLER_LR_OFFSET(r1)
mfcr r5
stw r7, 28(r1)
stw r8, 32(r1)
stw r9, 36(r1)
stw r10,40(r1)
stw r4, 44(r1)
cfi_rel_offset (lr, 44)
stw r5, 8(r1)
#ifndef SHARED
bl JUMPTARGET(__mcount_internal)
#else
bl __mcount_internal@local
#endif
/* Restore the registers... */
lwz r6, 8(r1)
lwz r0, 44(r1)
lwz r3, 12(r1)
mtctr r0
lwz r4, 16(r1)
mtcrf 0xff,r6
lwz r5, 20(r1)
lwz r6, 24(r1)
lwz r0, CALLER_LR_OFFSET(r1)
lwz r7, 28(r1)
lwz r8, 32(r1)
mtlr r0
lwz r9, 36(r1)
lwz r10,40(r1)
/* ...unwind the stack frame, and return to your usual programming. */
#if defined PIC && !defined SHARED
lwz r30, 48(r1)
addi r1,r1,64
#else
addi r1,r1,48
#endif
bctr
END(_mcount)
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