glibc/sysdeps/unix/sysv/linux/powerpc/powerpc64/socket.S
Ulrich Weigand 8b8a692cfd PowerPC64 ELFv2 ABI 4/6: Stack frame layout changes
This updates glibc for the changes in the ELFv2 relating to the
stack frame layout.  These are described in more detail here:
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01149.html
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01146.html

Specifically, the "compiler and linker doublewords" were removed,
which has the effect that the save slot for the TOC register is
now at offset 24 rather than 40 to the stack pointer.

In addition, a function may now no longer necessarily assume that
its caller has set up a 64-byte register save area its use.

To address the first change, the patch goes through all assembler
files and replaces immediate offsets in instructions accessing the
ABI-defined stack slots by symbolic offsets.  Those already were
defined in ucontext_i.sym and used in some of the context routines,
but that doesn't really seem like the right place for those defines.

The patch instead defines those symbolic offsets in sysdeps.h,
in two variants for the old and new ABI, and uses them systematically
in all assembler files, not just the context routines.

The second change only affected a few assembler files that used
the save area to temporarily store some registers.  In those
cases where this happens within a leaf function, this patch
changes the code to store those registers to the "red zone"
below the stack pointer.  Otherwise, the functions already allocate
a stack frame, and the patch changes them to add extra space in
these frames as temporary space for the ELFv2 ABI.
2013-12-04 07:41:39 -06:00

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ArmAsm

/* Copyright (C) 1995-2013 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
see <http://www.gnu.org/licenses/>. */
#include <sysdep-cancel.h>
#include <socketcall.h>
#define P(a, b) P2(a, b)
#define P2(a, b) a##b
/* The socket-oriented system calls are handled unusally in Linux.
They are all gated through the single `socketcall' system call number.
`socketcall' takes two arguments: the first is the subcode, specifying
which socket function is being called; and the second is a pointer to
the arguments to the specific function.
The .S files for the other calls just #define socket and #include this.
They also #define a 'number-of-arguments' word in NARGS, which
defaults to 3. */
#ifndef NARGS
#ifdef socket
#error NARGS not defined
#endif
#define NARGS 3
#endif
#ifndef __socket
# ifndef NO_WEAK_ALIAS
# define __socket P(__,socket)
# else
# define __socket socket
# endif
#endif
#if _CALL_ELF == 2
#define FRAMESIZE (FRAME_MIN_SIZE+16+64)
#define stackblock (FRAME_MIN_SIZE+16)
#else
#define FRAMESIZE (FRAME_MIN_SIZE+16)
#define stackblock (FRAMESIZE+FRAME_PARM_SAVE) /* offset to parm save area. */
#endif
.text
ENTRY(__socket)
CALL_MCOUNT NARGS
stdu r1,-FRAMESIZE(r1)
cfi_adjust_cfa_offset(FRAMESIZE)
#if NARGS >= 1
std r3,stackblock(r1)
#endif
#if NARGS >= 2
std r4,8+stackblock(r1)
#endif
#if NARGS >= 3
std r5,16+stackblock(r1)
#endif
#if NARGS >= 4
std r6,24+stackblock(r1)
#endif
#if NARGS >= 5
std r7,32+stackblock(r1)
#endif
#if NARGS >= 6
std r8,40+stackblock(r1)
#endif
#if NARGS >= 7
std r9,48+stackblock(r1)
#endif
#if NARGS >= 8
std r10,56+stackblock(r1)
#endif
#if NARGS >= 9
#error too many arguments!
#endif
#if defined NEED_CANCELLATION && defined CENABLE
SINGLE_THREAD_P
bne- .Lsocket_cancel
#endif
li r3,P(SOCKOP_,socket)
addi r4,r1,stackblock
DO_CALL(SYS_ify(socketcall))
addi r1,r1,FRAMESIZE
cfi_adjust_cfa_offset(-FRAMESIZE)
PSEUDO_RET
#if defined NEED_CANCELLATION && defined CENABLE
.Lsocket_cancel:
cfi_adjust_cfa_offset(FRAMESIZE)
mflr r9
std r9,FRAMESIZE+FRAME_LR_SAVE(r1)
cfi_offset (lr, FRAME_LR_SAVE)
CENABLE
std r3,FRAME_MIN_SIZE+8(r1)
li r3,P(SOCKOP_,socket)
addi r4,r1,stackblock
DO_CALL(SYS_ify(socketcall))
mfcr r0
std r3,FRAME_MIN_SIZE(r1)
std r0,FRAMESIZE+FRAME_CR_SAVE(r1)
cfi_offset (cr, FRAME_CR_SAVE)
ld r3,FRAME_MIN_SIZE+8(r1)
CDISABLE
ld r4,FRAMESIZE+FRAME_LR_SAVE(r1)
ld r0,FRAMESIZE+FRAME_CR_SAVE(r1)
ld r3,FRAME_MIN_SIZE(r1)
mtlr r4
mtcr r0
addi r1,r1,FRAMESIZE
cfi_adjust_cfa_offset(-FRAMESIZE)
cfi_restore(lr)
cfi_restore(cr)
PSEUDO_RET
#endif
PSEUDO_END (__socket)
#ifndef NO_WEAK_ALIAS
weak_alias (__socket, socket)
#endif