* sysdeps/powerpc/pt-machine.h

(HAS_COMPARE_AND_SWAP_WITH_RELEASE_SEMANTICS): Define. 
(__compare_and_swap): Remove memory barriers. 
(__compare_and_swap_with_release_semantics): New function.
2001-05-09  Geoff Keating  <geoffk@redhat.com>

	* sysdeps/powerpc/pt-machine.h 
	(HAS_COMPARE_AND_SWAP_WITH_RELEASE_SEMANTICS): Define.
	(__compare_and_swap): Remove memory barriers.
	(__compare_and_swap_with_release_semantics): New function.
This commit is contained in:
Geoff Keating 2001-05-17 19:47:46 +00:00
parent 33bdaa2c05
commit 0e47171f2f
2 changed files with 34 additions and 9 deletions

View File

@ -1,3 +1,10 @@
2001-05-09 Geoff Keating <geoffk@redhat.com>
* sysdeps/powerpc/pt-machine.h
(HAS_COMPARE_AND_SWAP_WITH_RELEASE_SEMANTICS): Define.
(__compare_and_swap): Remove memory barriers.
(__compare_and_swap_with_release_semantics): New function.
2001-04-24 Andreas Jaeger <aj@suse.de>
* wrapsyscall.c: send* and recv* return ssize_t.

View File

@ -1,6 +1,6 @@
/* Machine-dependent pthreads configuration and inline functions.
powerpc version.
Copyright (C) 1996, 1997, 1998, 2000 Free Software Foundation, Inc.
Copyright (C) 1996, 1997, 1998, 2000, 2001 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
@ -38,19 +38,38 @@ register char * stack_pointer __asm__ ("r1");
/* Compare-and-swap for semaphores. */
/* note that test-and-set(x) is the same as !compare-and-swap(x, 0, 1) */
#define HAS_COMPARE_AND_SWAP
#define HAS_COMPARE_AND_SWAP_WITH_RELEASE_SEMANTICS
#define IMPLEMENT_TAS_WITH_CAS
#if BROKEN_PPC_ASM_CR0
static
#else
PT_EI
#endif
int
PT_EI int
__compare_and_swap (long int *p, long int oldval, long int newval)
{
int ret;
__asm__ __volatile__ (
"0: lwarx %0,0,%1 ;"
" xor. %0,%3,%0;"
" bne 1f;"
" stwcx. %2,0,%1;"
" bne- 0b;"
"1: "
: "=&r"(ret)
: "r"(p), "r"(newval), "r"(oldval)
: "cr0", "memory");
/* This version of __compare_and_swap is to be used when acquiring
a lock, so we don't need to worry about whether other memory
operations have completed, but we do need to be sure that any loads
after this point really occur after we have acquired the lock. */
__asm__ __volatile__ ("isync" : : : "memory");
return ret == 0;
}
PT_EI int
__compare_and_swap_with_release_semantics (long int *p,
long int oldval, long int newval)
{
int ret;
MEMORY_BARRIER ();
__asm__ __volatile__ (
"0: lwarx %0,0,%1 ;"
@ -62,6 +81,5 @@ __compare_and_swap (long int *p, long int oldval, long int newval)
: "=&r"(ret)
: "r"(p), "r"(newval), "r"(oldval)
: "cr0", "memory");
MEMORY_BARRIER ();
return ret == 0;
}