mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-23 13:30:06 +00:00
78 lines
2.5 KiB
ArmAsm
78 lines
2.5 KiB
ArmAsm
/* 64 bit S/390-specific implemetation of profiling support.
|
|
Copyright (C) 2001-2014 Free Software Foundation, Inc.
|
|
Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com)
|
|
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/>. */
|
|
|
|
#include <sysdep.h>
|
|
|
|
/* How profiling works on 64 bit S/390:
|
|
On the start of each function _mcount is called with the address of a
|
|
data word in %r1 (initialized to 0, used for counting). The compiler
|
|
with the option -p generates code of the form:
|
|
|
|
STM 6,15,24(15)
|
|
BRAS 13,.LTN0_0
|
|
.LT0_0:
|
|
.LC13: .long .LP0
|
|
.data
|
|
.align 4
|
|
.LP0: .long 0
|
|
.text
|
|
# function profiler
|
|
stg 14,4(15)
|
|
lg 1,.LC13-.LT0_0(13)
|
|
brasl 14,_mcount
|
|
lg 14,4(15)
|
|
|
|
The _mcount implementation now has to call __mcount_internal with the
|
|
address of .LP0 as first parameter and the return address as second
|
|
parameter. &.LP0 was loaded to %r1 and the return address is in %r14.
|
|
_mcount may not modify any register. */
|
|
|
|
.globl C_SYMBOL_NAME(_mcount)
|
|
.type C_SYMBOL_NAME(_mcount), @function
|
|
cfi_startproc
|
|
.align ALIGNARG(4)
|
|
C_LABEL(_mcount)
|
|
/* Save the caller-clobbered registers. */
|
|
aghi %r15,-224
|
|
cfi_adjust_cfa_offset (224)
|
|
stmg %r14,%r5,160(%r15)
|
|
cfi_offset (r14, 0)
|
|
cfi_offset (r15, 8)
|
|
lg %r2,232(%r15) # callers address = first parameter
|
|
la %r2,0(%r2) # clear bit 0
|
|
la %r3,0(%r14) # callees address = second parameter
|
|
|
|
#ifdef PIC
|
|
brasl %r14,__mcount_internal@PLT
|
|
#else
|
|
brasl %r14,__mcount_internal
|
|
#endif
|
|
|
|
/* Pop the saved registers. Please note that `mcount' has no
|
|
return value. */
|
|
lmg %r14,%r5,160(%r15)
|
|
aghi %r15,224
|
|
cfi_adjust_cfa_offset (-224)
|
|
br %r14
|
|
cfi_endproc
|
|
ASM_SIZE_DIRECTIVE(C_SYMBOL_NAME(_mcount))
|
|
|
|
#undef mcount
|
|
weak_alias (_mcount, mcount)
|