glibc/sysdeps/unix/sysv/linux/powerpc/elision-unlock.c
Zack Weinberg a053e87849
Remove support for PowerPC SPE extension (powerpc*-*-*gnuspe*).
GCC 9 dropped support for the SPE extensions to PowerPC, which means
powerpc*-*-*gnuspe* configurations are no longer buildable with that
compiler.  This ISA extension was peculiar to the “e500” line of
embedded PowerPC chips, which, as far as I can tell, are no longer
being manufactured, so I think we should follow suit.

This patch was developed by grepping for “e500”, “__SPE__”, and
“__NO_FPRS__”, and may not eliminate every vestige of SPE support.
Most uses of __NO_FPRS__ are left alone, as they are relevant to
normal embedded PowerPC with soft-float.

        * sysdeps/powerpc/preconfigure: Error out on powerpc-*-*gnuspe*
        host type.
        * scripts/build-many-glibcs.py: Remove powerpc-*-linux-gnuspe
        and powerpc-*-linux-gnuspe-e500v1 from list of build configurations.

        * sysdeps/powerpc/powerpc32/e500: Recursively delete.
        * sysdeps/unix/sysv/linux/powerpc/powerpc32/e500: Recursively delete.
        * sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/context-e500.h:
        Delete.

        * sysdeps/powerpc/fpu_control.h: Remove SPE variant.
        Issue an #error if used with a compiler in SPE-float mode.
        * sysdeps/powerpc/powerpc32/__longjmp_common.S
        * sysdeps/powerpc/powerpc32/setjmp_common.S
        * sysdeps/unix/sysv/linux/powerpc/powerpc32/getcontext-common.S
        * sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/getcontext.S
        * sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/setcontext.S
        * sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/swapcontext.S
        * sysdeps/unix/sysv/linux/powerpc/powerpc32/setcontext-common.S
        * sysdeps/unix/sysv/linux/powerpc/powerpc32/swapcontext-common.S:
        Remove code to preserve SPE register state.

        * sysdeps/unix/sysv/linux/powerpc/elision-lock.c
        * sysdeps/unix/sysv/linux/powerpc/elision-trylock.c
        * sysdeps/unix/sysv/linux/powerpc/elision-unlock.c
        Remove __SPE__ ifndefs.
2019-05-22 10:05:40 -04:00

44 lines
1.5 KiB
C

/* elision-unlock.c: Commit an elided pthread lock.
Copyright (C) 2015-2019 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
<http://www.gnu.org/licenses/>. */
#include "pthreadP.h"
#include "lowlevellock.h"
#include "htm.h"
int
__lll_unlock_elision (int *lock, short *adapt_count, int pshared)
{
/* When the lock was free we're in a transaction. */
if (*lock == 0)
__libc_tend (0);
else
{
/* Update adapt_count in the critical section to prevent a
write-after-destroy error as mentioned in BZ 20822. The
following update of adapt_count has to be contained within
the critical region of the fall-back lock in order to not violate
the mutex destruction requirements. */
short __tmp = atomic_load_relaxed (adapt_count);
if (__tmp > 0)
atomic_store_relaxed (adapt_count, __tmp - 1);
lll_unlock ((*lock), pshared);
}
return 0;
}