mirror of
https://github.com/autc04/Retro68.git
synced 2024-12-01 11:52:47 +00:00
685 lines
24 KiB
C
685 lines
24 KiB
C
|
/*
|
||
|
* Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
|
||
|
* Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
|
||
|
* Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved.
|
||
|
* Copyright (c) 1999 by Hewlett-Packard Company. All rights reserved.
|
||
|
*
|
||
|
*
|
||
|
* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
|
||
|
* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
|
||
|
*
|
||
|
* Permission is hereby granted to use or copy this program
|
||
|
* for any purpose, provided the above notices are retained on all copies.
|
||
|
* Permission to modify the code and to distribute modified code is granted,
|
||
|
* provided the above notices are retained, and a notice that the code was
|
||
|
* modified is included with the above copyright notice.
|
||
|
*/
|
||
|
|
||
|
#ifndef GC_LOCKS_H
|
||
|
#define GC_LOCKS_H
|
||
|
|
||
|
/*
|
||
|
* Mutual exclusion between allocator/collector routines.
|
||
|
* Needed if there is more than one allocator thread.
|
||
|
* FASTLOCK() is assumed to try to acquire the lock in a cheap and
|
||
|
* dirty way that is acceptable for a few instructions, e.g. by
|
||
|
* inhibiting preemption. This is assumed to have succeeded only
|
||
|
* if a subsequent call to FASTLOCK_SUCCEEDED() returns TRUE.
|
||
|
* FASTUNLOCK() is called whether or not FASTLOCK_SUCCEEDED().
|
||
|
* If signals cannot be tolerated with the FASTLOCK held, then
|
||
|
* FASTLOCK should disable signals. The code executed under
|
||
|
* FASTLOCK is otherwise immune to interruption, provided it is
|
||
|
* not restarted.
|
||
|
* DCL_LOCK_STATE declares any local variables needed by LOCK and UNLOCK
|
||
|
* and/or DISABLE_SIGNALS and ENABLE_SIGNALS and/or FASTLOCK.
|
||
|
* (There is currently no equivalent for FASTLOCK.)
|
||
|
*
|
||
|
* In the PARALLEL_MARK case, we also need to define a number of
|
||
|
* other inline finctions here:
|
||
|
* GC_bool GC_compare_and_exchange( volatile GC_word *addr,
|
||
|
* GC_word old, GC_word new )
|
||
|
* GC_word GC_atomic_add( volatile GC_word *addr, GC_word how_much )
|
||
|
* void GC_memory_barrier( )
|
||
|
*
|
||
|
*/
|
||
|
# ifdef THREADS
|
||
|
void GC_noop1 GC_PROTO((word));
|
||
|
# ifdef PCR_OBSOLETE /* Faster, but broken with multiple lwp's */
|
||
|
# include "th/PCR_Th.h"
|
||
|
# include "th/PCR_ThCrSec.h"
|
||
|
extern struct PCR_Th_MLRep GC_allocate_ml;
|
||
|
# define DCL_LOCK_STATE PCR_sigset_t GC_old_sig_mask
|
||
|
# define LOCK() PCR_Th_ML_Acquire(&GC_allocate_ml)
|
||
|
# define UNLOCK() PCR_Th_ML_Release(&GC_allocate_ml)
|
||
|
# define UNLOCK() PCR_Th_ML_Release(&GC_allocate_ml)
|
||
|
# define FASTLOCK() PCR_ThCrSec_EnterSys()
|
||
|
/* Here we cheat (a lot): */
|
||
|
# define FASTLOCK_SUCCEEDED() (*(int *)(&GC_allocate_ml) == 0)
|
||
|
/* TRUE if nobody currently holds the lock */
|
||
|
# define FASTUNLOCK() PCR_ThCrSec_ExitSys()
|
||
|
# endif
|
||
|
# ifdef PCR
|
||
|
# include <base/PCR_Base.h>
|
||
|
# include <th/PCR_Th.h>
|
||
|
extern PCR_Th_ML GC_allocate_ml;
|
||
|
# define DCL_LOCK_STATE \
|
||
|
PCR_ERes GC_fastLockRes; PCR_sigset_t GC_old_sig_mask
|
||
|
# define LOCK() PCR_Th_ML_Acquire(&GC_allocate_ml)
|
||
|
# define UNLOCK() PCR_Th_ML_Release(&GC_allocate_ml)
|
||
|
# define FASTLOCK() (GC_fastLockRes = PCR_Th_ML_Try(&GC_allocate_ml))
|
||
|
# define FASTLOCK_SUCCEEDED() (GC_fastLockRes == PCR_ERes_okay)
|
||
|
# define FASTUNLOCK() {\
|
||
|
if( FASTLOCK_SUCCEEDED() ) PCR_Th_ML_Release(&GC_allocate_ml); }
|
||
|
# endif
|
||
|
# ifdef SRC_M3
|
||
|
extern GC_word RT0u__inCritical;
|
||
|
# define LOCK() RT0u__inCritical++
|
||
|
# define UNLOCK() RT0u__inCritical--
|
||
|
# endif
|
||
|
# ifdef GC_SOLARIS_THREADS
|
||
|
# include <thread.h>
|
||
|
# include <signal.h>
|
||
|
extern mutex_t GC_allocate_ml;
|
||
|
# define LOCK() mutex_lock(&GC_allocate_ml);
|
||
|
# define UNLOCK() mutex_unlock(&GC_allocate_ml);
|
||
|
# endif
|
||
|
|
||
|
/* Try to define GC_TEST_AND_SET and a matching GC_CLEAR for spin lock */
|
||
|
/* acquisition and release. We need this for correct operation of the */
|
||
|
/* incremental GC. */
|
||
|
# ifdef __GNUC__
|
||
|
# if defined(I386)
|
||
|
inline static int GC_test_and_set(volatile unsigned int *addr) {
|
||
|
int oldval;
|
||
|
/* Note: the "xchg" instruction does not need a "lock" prefix */
|
||
|
__asm__ __volatile__("xchgl %0, %1"
|
||
|
: "=r"(oldval), "=m"(*(addr))
|
||
|
: "0"(1), "m"(*(addr)) : "memory");
|
||
|
return oldval;
|
||
|
}
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
# endif
|
||
|
# if defined(IA64)
|
||
|
# include <ia64intrin.h>
|
||
|
inline static int GC_test_and_set(volatile unsigned int *addr) {
|
||
|
return __sync_lock_test_and_set(addr, 1);
|
||
|
}
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
inline static void GC_clear(volatile unsigned int *addr) {
|
||
|
*addr = 0;
|
||
|
}
|
||
|
# define GC_CLEAR_DEFINED
|
||
|
# endif
|
||
|
# ifdef SPARC
|
||
|
inline static int GC_test_and_set(volatile unsigned int *addr) {
|
||
|
int oldval;
|
||
|
|
||
|
__asm__ __volatile__("ldstub %1,%0"
|
||
|
: "=r"(oldval), "=m"(*addr)
|
||
|
: "m"(*addr) : "memory");
|
||
|
return oldval;
|
||
|
}
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
# endif
|
||
|
# ifdef M68K
|
||
|
/* Contributed by Tony Mantler. I'm not sure how well it was */
|
||
|
/* tested. */
|
||
|
inline static int GC_test_and_set(volatile unsigned int *addr) {
|
||
|
char oldval; /* this must be no longer than 8 bits */
|
||
|
|
||
|
/* The return value is semi-phony. */
|
||
|
/* 'tas' sets bit 7 while the return */
|
||
|
/* value pretends bit 0 was set */
|
||
|
__asm__ __volatile__(
|
||
|
"tas %1@; sne %0; negb %0"
|
||
|
: "=d" (oldval)
|
||
|
: "a" (addr) : "memory");
|
||
|
return oldval;
|
||
|
}
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
# endif
|
||
|
# if defined(POWERPC)
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
# define GC_CLEAR_DEFINED
|
||
|
# if (__GNUC__>4)||((__GNUC__==4)&&(__GNUC_MINOR__>=4))
|
||
|
# define GC_test_and_set(addr) __sync_lock_test_and_set (addr, 1)
|
||
|
# define GC_clear(addr) __sync_lock_release (addr)
|
||
|
# else
|
||
|
inline static int GC_test_and_set(volatile unsigned int *addr) {
|
||
|
int oldval;
|
||
|
int temp = 1; /* locked value */
|
||
|
|
||
|
__asm__ __volatile__(
|
||
|
"\n1:\n"
|
||
|
"\tlwarx %0,%y3\n" /* load and reserve, 32-bits */
|
||
|
"\tcmpwi %0, 0\n" /* if load is */
|
||
|
"\tbne 2f\n" /* non-zero, return already set */
|
||
|
"\tstwcx. %2,%y3\n" /* else store conditional */
|
||
|
"\tbne- 1b\n" /* retry if lost reservation */
|
||
|
"\tsync\n" /* import barrier */
|
||
|
"2:\t\n" /* oldval is zero if we set */
|
||
|
: "=&r"(oldval), "=m"(addr)
|
||
|
: "r"(temp), "Z"(addr)
|
||
|
: "cr0","memory");
|
||
|
return oldval;
|
||
|
}
|
||
|
inline static void GC_clear(volatile unsigned int *addr) {
|
||
|
__asm__ __volatile__("lwsync" : : : "memory");
|
||
|
*(addr) = 0;
|
||
|
}
|
||
|
# endif
|
||
|
# endif
|
||
|
# if defined(ALPHA)
|
||
|
inline static int GC_test_and_set(volatile unsigned int * addr)
|
||
|
{
|
||
|
unsigned long oldvalue;
|
||
|
unsigned long temp;
|
||
|
|
||
|
__asm__ __volatile__(
|
||
|
"1: ldl_l %0,%1\n"
|
||
|
" and %0,%3,%2\n"
|
||
|
" bne %2,2f\n"
|
||
|
" xor %0,%3,%0\n"
|
||
|
" stl_c %0,%1\n"
|
||
|
# ifdef __ELF__
|
||
|
" beq %0,3f\n"
|
||
|
# else
|
||
|
" beq %0,1b\n"
|
||
|
# endif
|
||
|
" mb\n"
|
||
|
"2:\n"
|
||
|
# ifdef __ELF__
|
||
|
".section .text2,\"ax\"\n"
|
||
|
"3: br 1b\n"
|
||
|
".previous"
|
||
|
# endif
|
||
|
:"=&r" (temp), "=m" (*addr), "=&r" (oldvalue)
|
||
|
:"Ir" (1), "m" (*addr)
|
||
|
:"memory");
|
||
|
|
||
|
return oldvalue;
|
||
|
}
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
inline static void GC_clear(volatile unsigned int *addr) {
|
||
|
__asm__ __volatile__("mb" : : : "memory");
|
||
|
*(addr) = 0;
|
||
|
}
|
||
|
# define GC_CLEAR_DEFINED
|
||
|
# endif /* ALPHA */
|
||
|
# ifdef ARM32
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
# if (__GNUC__>4)||((__GNUC__==4)&&(__GNUC_MINOR__>=5)) && defined(__ARM_EABI__)
|
||
|
# define GC_CLEAR_DEFINED
|
||
|
# define GC_test_and_set(addr) __sync_lock_test_and_set (addr, 1)
|
||
|
# define GC_clear(addr) __sync_lock_release (addr)
|
||
|
# else
|
||
|
inline static int GC_test_and_set(volatile unsigned int *addr) {
|
||
|
int oldval;
|
||
|
/* SWP on ARM is very similar to XCHG on x86. Doesn't lock the
|
||
|
* bus because there are no SMP ARM machines. If/when there are,
|
||
|
* this code will likely need to be updated. */
|
||
|
/* See linuxthreads/sysdeps/arm/pt-machine.h in glibc-2.1 */
|
||
|
__asm__ __volatile__("swp %0, %1, [%2]"
|
||
|
: "=r"(oldval)
|
||
|
: "0"(1), "r"(addr)
|
||
|
: "memory");
|
||
|
return oldval;
|
||
|
}
|
||
|
# endif
|
||
|
# endif /* ARM32 */
|
||
|
# ifdef CRIS
|
||
|
inline static int GC_test_and_set(volatile unsigned int *addr) {
|
||
|
/* Ripped from linuxthreads/sysdeps/cris/pt-machine.h. */
|
||
|
/* Included with Hans-Peter Nilsson's permission. */
|
||
|
register unsigned long int ret;
|
||
|
|
||
|
/* Note the use of a dummy output of *addr to expose the write.
|
||
|
* The memory barrier is to stop *other* writes being moved past
|
||
|
* this code.
|
||
|
*/
|
||
|
__asm__ __volatile__("clearf\n"
|
||
|
"0:\n\t"
|
||
|
"movu.b [%2],%0\n\t"
|
||
|
"ax\n\t"
|
||
|
"move.b %3,[%2]\n\t"
|
||
|
"bwf 0b\n\t"
|
||
|
"clearf"
|
||
|
: "=&r" (ret), "=m" (*addr)
|
||
|
: "r" (addr), "r" ((int) 1), "m" (*addr)
|
||
|
: "memory");
|
||
|
return ret;
|
||
|
}
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
# endif /* CRIS */
|
||
|
# ifdef S390
|
||
|
inline static int GC_test_and_set(volatile unsigned int *addr) {
|
||
|
int ret;
|
||
|
__asm__ __volatile__ (
|
||
|
" l %0,0(%2)\n"
|
||
|
"0: cs %0,%1,0(%2)\n"
|
||
|
" jl 0b"
|
||
|
: "=&d" (ret)
|
||
|
: "d" (1), "a" (addr)
|
||
|
: "cc", "memory");
|
||
|
return ret;
|
||
|
}
|
||
|
# endif
|
||
|
# endif /* __GNUC__ */
|
||
|
# if (defined(ALPHA) && !defined(__GNUC__))
|
||
|
# ifndef OSF1
|
||
|
--> We currently assume that if gcc is not used, we are
|
||
|
--> running under Tru64.
|
||
|
# endif
|
||
|
# include <machine/builtins.h>
|
||
|
# include <c_asm.h>
|
||
|
# define GC_test_and_set(addr) __ATOMIC_EXCH_LONG(addr, 1)
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
# define GC_clear(addr) { asm("mb"); *(volatile unsigned *)addr = 0; }
|
||
|
# define GC_CLEAR_DEFINED
|
||
|
# endif
|
||
|
# if defined(MSWIN32)
|
||
|
# define GC_test_and_set(addr) InterlockedExchange((LPLONG)addr,1)
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
# endif
|
||
|
# ifdef MIPS
|
||
|
# ifdef LINUX
|
||
|
# include <sys/tas.h>
|
||
|
# define GC_test_and_set(addr) _test_and_set((int *) addr,1)
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
# elif __mips < 3 || !(defined (_ABIN32) || defined(_ABI64)) \
|
||
|
|| !defined(_COMPILER_VERSION) || _COMPILER_VERSION < 700
|
||
|
# ifdef __GNUC__
|
||
|
# define GC_test_and_set(addr) _test_and_set((void *)addr,1)
|
||
|
# else
|
||
|
# define GC_test_and_set(addr) test_and_set((void *)addr,1)
|
||
|
# endif
|
||
|
# else
|
||
|
# include <sgidefs.h>
|
||
|
# include <mutex.h>
|
||
|
# define GC_test_and_set(addr) __test_and_set32((void *)addr,1)
|
||
|
# define GC_clear(addr) __lock_release(addr);
|
||
|
# define GC_CLEAR_DEFINED
|
||
|
# endif
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
# endif /* MIPS */
|
||
|
# if defined(_AIX)
|
||
|
# include <sys/atomic_op.h>
|
||
|
# if (defined(_POWER) || defined(_POWERPC))
|
||
|
# if defined(__GNUC__)
|
||
|
inline static void GC_memsync() {
|
||
|
__asm__ __volatile__ ("sync" : : : "memory");
|
||
|
}
|
||
|
# else
|
||
|
# ifndef inline
|
||
|
# define inline __inline
|
||
|
# endif
|
||
|
# pragma mc_func GC_memsync { \
|
||
|
"7c0004ac" /* sync (same opcode used for dcs)*/ \
|
||
|
}
|
||
|
# endif
|
||
|
# else
|
||
|
# error dont know how to memsync
|
||
|
# endif
|
||
|
inline static int GC_test_and_set(volatile unsigned int * addr) {
|
||
|
int oldvalue = 0;
|
||
|
if (compare_and_swap((void *)addr, &oldvalue, 1)) {
|
||
|
GC_memsync();
|
||
|
return 0;
|
||
|
} else return 1;
|
||
|
}
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
inline static void GC_clear(volatile unsigned int *addr) {
|
||
|
GC_memsync();
|
||
|
*(addr) = 0;
|
||
|
}
|
||
|
# define GC_CLEAR_DEFINED
|
||
|
|
||
|
# endif
|
||
|
# if 0 /* defined(HP_PA) */
|
||
|
/* The official recommendation seems to be to not use ldcw from */
|
||
|
/* user mode. Since multithreaded incremental collection doesn't */
|
||
|
/* work anyway on HP_PA, this shouldn't be a major loss. */
|
||
|
|
||
|
/* "set" means 0 and "clear" means 1 here. */
|
||
|
# define GC_test_and_set(addr) !GC_test_and_clear(addr);
|
||
|
# define GC_TEST_AND_SET_DEFINED
|
||
|
# define GC_clear(addr) GC_noop1((word)(addr)); *(volatile unsigned int *)addr = 1;
|
||
|
/* The above needs a memory barrier! */
|
||
|
# define GC_CLEAR_DEFINED
|
||
|
# endif
|
||
|
# if defined(GC_TEST_AND_SET_DEFINED) && !defined(GC_CLEAR_DEFINED)
|
||
|
# ifdef __GNUC__
|
||
|
inline static void GC_clear(volatile unsigned int *addr) {
|
||
|
/* Try to discourage gcc from moving anything past this. */
|
||
|
__asm__ __volatile__(" " : : : "memory");
|
||
|
*(addr) = 0;
|
||
|
}
|
||
|
# else
|
||
|
/* The function call in the following should prevent the */
|
||
|
/* compiler from moving assignments to below the UNLOCK. */
|
||
|
# define GC_clear(addr) GC_noop1((word)(addr)); \
|
||
|
*((volatile unsigned int *)(addr)) = 0;
|
||
|
# endif
|
||
|
# define GC_CLEAR_DEFINED
|
||
|
# endif /* !GC_CLEAR_DEFINED */
|
||
|
|
||
|
# if !defined(GC_TEST_AND_SET_DEFINED)
|
||
|
# define USE_PTHREAD_LOCKS
|
||
|
# endif
|
||
|
|
||
|
# if defined(GC_PTHREADS) && !defined(GC_SOLARIS_THREADS) \
|
||
|
&& !defined(GC_WIN32_THREADS)
|
||
|
# define NO_THREAD (pthread_t)(-1)
|
||
|
# include <pthread.h>
|
||
|
# if defined(PARALLEL_MARK)
|
||
|
/* We need compare-and-swap to update mark bits, where it's */
|
||
|
/* performance critical. If USE_MARK_BYTES is defined, it is */
|
||
|
/* no longer needed for this purpose. However we use it in */
|
||
|
/* either case to implement atomic fetch-and-add, though that's */
|
||
|
/* less performance critical, and could perhaps be done with */
|
||
|
/* a lock. */
|
||
|
# if defined(GENERIC_COMPARE_AND_SWAP)
|
||
|
/* Probably not useful, except for debugging. */
|
||
|
/* We do use GENERIC_COMPARE_AND_SWAP on PA_RISC, but we */
|
||
|
/* minimize its use. */
|
||
|
extern pthread_mutex_t GC_compare_and_swap_lock;
|
||
|
|
||
|
/* Note that if GC_word updates are not atomic, a concurrent */
|
||
|
/* reader should acquire GC_compare_and_swap_lock. On */
|
||
|
/* currently supported platforms, such updates are atomic. */
|
||
|
extern GC_bool GC_compare_and_exchange(volatile GC_word *addr,
|
||
|
GC_word old, GC_word new_val);
|
||
|
# endif /* GENERIC_COMPARE_AND_SWAP */
|
||
|
# if defined(I386)
|
||
|
# if !defined(GENERIC_COMPARE_AND_SWAP)
|
||
|
/* Returns TRUE if the comparison succeeded. */
|
||
|
inline static GC_bool GC_compare_and_exchange(volatile GC_word *addr,
|
||
|
GC_word old,
|
||
|
GC_word new_val)
|
||
|
{
|
||
|
char result;
|
||
|
__asm__ __volatile__("lock; cmpxchgl %2, %0; setz %1"
|
||
|
: "+m"(*(addr)), "=r"(result)
|
||
|
: "r" (new_val), "a"(old) : "memory");
|
||
|
return (GC_bool) result;
|
||
|
}
|
||
|
# endif /* !GENERIC_COMPARE_AND_SWAP */
|
||
|
inline static void GC_memory_barrier()
|
||
|
{
|
||
|
/* We believe the processor ensures at least processor */
|
||
|
/* consistent ordering. Thus a compiler barrier */
|
||
|
/* should suffice. */
|
||
|
__asm__ __volatile__("" : : : "memory");
|
||
|
}
|
||
|
# endif /* I386 */
|
||
|
|
||
|
# if defined(POWERPC)
|
||
|
# if !defined(GENERIC_COMPARE_AND_SWAP)
|
||
|
# if CPP_WORDSZ == 64
|
||
|
/* Returns TRUE if the comparison succeeded. */
|
||
|
inline static GC_bool GC_compare_and_exchange(volatile GC_word *addr,
|
||
|
GC_word old, GC_word new_val)
|
||
|
{
|
||
|
unsigned long result, dummy;
|
||
|
__asm__ __volatile__(
|
||
|
"1:\tldarx %0,0,%5\n"
|
||
|
"\tcmpd %0,%4\n"
|
||
|
"\tbne 2f\n"
|
||
|
"\tstdcx. %3,0,%2\n"
|
||
|
"\tbne- 1b\n"
|
||
|
"\tsync\n"
|
||
|
"\tli %1, 1\n"
|
||
|
"\tb 3f\n"
|
||
|
"2:\tli %1, 0\n"
|
||
|
"3:\t\n"
|
||
|
: "=&r" (dummy), "=r" (result), "=p" (addr)
|
||
|
: "r" (new_val), "r" (old), "2"(addr)
|
||
|
: "cr0","memory");
|
||
|
return (GC_bool) result;
|
||
|
}
|
||
|
# else
|
||
|
/* Returns TRUE if the comparison succeeded. */
|
||
|
inline static GC_bool GC_compare_and_exchange(volatile GC_word *addr,
|
||
|
GC_word old, GC_word new_val)
|
||
|
{
|
||
|
int result, dummy;
|
||
|
__asm__ __volatile__(
|
||
|
"1:\tlwarx %0,0,%5\n"
|
||
|
"\tcmpw %0,%4\n"
|
||
|
"\tbne 2f\n"
|
||
|
"\tstwcx. %3,0,%2\n"
|
||
|
"\tbne- 1b\n"
|
||
|
"\tsync\n"
|
||
|
"\tli %1, 1\n"
|
||
|
"\tb 3f\n"
|
||
|
"2:\tli %1, 0\n"
|
||
|
"3:\t\n"
|
||
|
: "=&r" (dummy), "=r" (result), "=p" (addr)
|
||
|
: "r" (new_val), "r" (old), "2"(addr)
|
||
|
: "cr0","memory");
|
||
|
return (GC_bool) result;
|
||
|
}
|
||
|
# endif
|
||
|
# endif /* !GENERIC_COMPARE_AND_SWAP */
|
||
|
inline static void GC_memory_barrier()
|
||
|
{
|
||
|
__asm__ __volatile__("sync" : : : "memory");
|
||
|
}
|
||
|
# endif /* POWERPC */
|
||
|
|
||
|
# if defined(IA64)
|
||
|
# if !defined(GENERIC_COMPARE_AND_SWAP)
|
||
|
inline static GC_bool GC_compare_and_exchange(volatile GC_word *addr,
|
||
|
GC_word old,
|
||
|
GC_word new_val)
|
||
|
{
|
||
|
return __sync_bool_compare_and_swap (addr, old, new_val);
|
||
|
}
|
||
|
# endif /* !GENERIC_COMPARE_AND_SWAP */
|
||
|
# if 0
|
||
|
/* Shouldn't be needed; we use volatile stores instead. */
|
||
|
inline static void GC_memory_barrier()
|
||
|
{
|
||
|
__sync_synchronize ();
|
||
|
}
|
||
|
# endif /* 0 */
|
||
|
# endif /* IA64 */
|
||
|
# if defined(ALPHA)
|
||
|
# if !defined(GENERIC_COMPARE_AND_SWAP)
|
||
|
# if defined(__GNUC__)
|
||
|
inline static GC_bool GC_compare_and_exchange(volatile GC_word *addr,
|
||
|
GC_word old, GC_word new_val)
|
||
|
{
|
||
|
unsigned long was_equal;
|
||
|
unsigned long temp;
|
||
|
|
||
|
__asm__ __volatile__(
|
||
|
"1: ldq_l %0,%1\n"
|
||
|
" cmpeq %0,%4,%2\n"
|
||
|
" mov %3,%0\n"
|
||
|
" beq %2,2f\n"
|
||
|
" stq_c %0,%1\n"
|
||
|
" beq %0,1b\n"
|
||
|
"2:\n"
|
||
|
" mb\n"
|
||
|
:"=&r" (temp), "=m" (*addr), "=&r" (was_equal)
|
||
|
: "r" (new_val), "Ir" (old)
|
||
|
:"memory");
|
||
|
return was_equal;
|
||
|
}
|
||
|
# else /* !__GNUC__ */
|
||
|
inline static GC_bool GC_compare_and_exchange(volatile GC_word *addr,
|
||
|
GC_word old, GC_word new_val)
|
||
|
{
|
||
|
return __CMP_STORE_QUAD(addr, old, new_val, addr);
|
||
|
}
|
||
|
# endif /* !__GNUC__ */
|
||
|
# endif /* !GENERIC_COMPARE_AND_SWAP */
|
||
|
# ifdef __GNUC__
|
||
|
inline static void GC_memory_barrier()
|
||
|
{
|
||
|
__asm__ __volatile__("mb" : : : "memory");
|
||
|
}
|
||
|
# else
|
||
|
# define GC_memory_barrier() asm("mb")
|
||
|
# endif /* !__GNUC__ */
|
||
|
# endif /* ALPHA */
|
||
|
# if defined(S390)
|
||
|
# if !defined(GENERIC_COMPARE_AND_SWAP)
|
||
|
inline static GC_bool GC_compare_and_exchange(volatile C_word *addr,
|
||
|
GC_word old, GC_word new_val)
|
||
|
{
|
||
|
int retval;
|
||
|
__asm__ __volatile__ (
|
||
|
# ifndef __s390x__
|
||
|
" cs %1,%2,0(%3)\n"
|
||
|
# else
|
||
|
" csg %1,%2,0(%3)\n"
|
||
|
# endif
|
||
|
" ipm %0\n"
|
||
|
" srl %0,28\n"
|
||
|
: "=&d" (retval), "+d" (old)
|
||
|
: "d" (new_val), "a" (addr)
|
||
|
: "cc", "memory");
|
||
|
return retval == 0;
|
||
|
}
|
||
|
# endif
|
||
|
# endif
|
||
|
# if !defined(GENERIC_COMPARE_AND_SWAP)
|
||
|
/* Returns the original value of *addr. */
|
||
|
inline static GC_word GC_atomic_add(volatile GC_word *addr,
|
||
|
GC_word how_much)
|
||
|
{
|
||
|
GC_word old;
|
||
|
do {
|
||
|
old = *addr;
|
||
|
} while (!GC_compare_and_exchange(addr, old, old+how_much));
|
||
|
return old;
|
||
|
}
|
||
|
# else /* GENERIC_COMPARE_AND_SWAP */
|
||
|
/* So long as a GC_word can be atomically updated, it should */
|
||
|
/* be OK to read *addr without a lock. */
|
||
|
extern GC_word GC_atomic_add(volatile GC_word *addr, GC_word how_much);
|
||
|
# endif /* GENERIC_COMPARE_AND_SWAP */
|
||
|
|
||
|
# endif /* PARALLEL_MARK */
|
||
|
|
||
|
# if !defined(THREAD_LOCAL_ALLOC) && !defined(USE_PTHREAD_LOCKS)
|
||
|
/* In the THREAD_LOCAL_ALLOC case, the allocation lock tends to */
|
||
|
/* be held for long periods, if it is held at all. Thus spinning */
|
||
|
/* and sleeping for fixed periods are likely to result in */
|
||
|
/* significant wasted time. We thus rely mostly on queued locks. */
|
||
|
# define USE_SPIN_LOCK
|
||
|
extern volatile unsigned int GC_allocate_lock;
|
||
|
extern void GC_lock(void);
|
||
|
/* Allocation lock holder. Only set if acquired by client through */
|
||
|
/* GC_call_with_alloc_lock. */
|
||
|
# ifdef GC_ASSERTIONS
|
||
|
# define LOCK() \
|
||
|
{ if (GC_test_and_set(&GC_allocate_lock)) GC_lock(); \
|
||
|
SET_LOCK_HOLDER(); }
|
||
|
# define UNLOCK() \
|
||
|
{ GC_ASSERT(I_HOLD_LOCK()); UNSET_LOCK_HOLDER(); \
|
||
|
GC_clear(&GC_allocate_lock); }
|
||
|
# else
|
||
|
# define LOCK() \
|
||
|
{ if (GC_test_and_set(&GC_allocate_lock)) GC_lock(); }
|
||
|
# define UNLOCK() \
|
||
|
GC_clear(&GC_allocate_lock)
|
||
|
# endif /* !GC_ASSERTIONS */
|
||
|
# if 0
|
||
|
/* Another alternative for OSF1 might be: */
|
||
|
# include <sys/mman.h>
|
||
|
extern msemaphore GC_allocate_semaphore;
|
||
|
# define LOCK() { if (msem_lock(&GC_allocate_semaphore, MSEM_IF_NOWAIT) \
|
||
|
!= 0) GC_lock(); else GC_allocate_lock = 1; }
|
||
|
/* The following is INCORRECT, since the memory model is too weak. */
|
||
|
/* Is this true? Presumably msem_unlock has the right semantics? */
|
||
|
/* - HB */
|
||
|
# define UNLOCK() { GC_allocate_lock = 0; \
|
||
|
msem_unlock(&GC_allocate_semaphore, 0); }
|
||
|
# endif /* 0 */
|
||
|
# else /* THREAD_LOCAL_ALLOC || USE_PTHREAD_LOCKS */
|
||
|
# ifndef USE_PTHREAD_LOCKS
|
||
|
# define USE_PTHREAD_LOCKS
|
||
|
# endif
|
||
|
# endif /* THREAD_LOCAL_ALLOC */
|
||
|
# ifdef USE_PTHREAD_LOCKS
|
||
|
# include <pthread.h>
|
||
|
extern pthread_mutex_t GC_allocate_ml;
|
||
|
# ifdef GC_ASSERTIONS
|
||
|
# define LOCK() \
|
||
|
{ GC_lock(); \
|
||
|
SET_LOCK_HOLDER(); }
|
||
|
# define UNLOCK() \
|
||
|
{ GC_ASSERT(I_HOLD_LOCK()); UNSET_LOCK_HOLDER(); \
|
||
|
pthread_mutex_unlock(&GC_allocate_ml); }
|
||
|
# else /* !GC_ASSERTIONS */
|
||
|
# if defined(NO_PTHREAD_TRYLOCK)
|
||
|
# define LOCK() GC_lock();
|
||
|
# else /* !defined(NO_PTHREAD_TRYLOCK) */
|
||
|
# define LOCK() \
|
||
|
{ if (0 != pthread_mutex_trylock(&GC_allocate_ml)) GC_lock(); }
|
||
|
# endif
|
||
|
# define UNLOCK() pthread_mutex_unlock(&GC_allocate_ml)
|
||
|
# endif /* !GC_ASSERTIONS */
|
||
|
# endif /* USE_PTHREAD_LOCKS */
|
||
|
# define SET_LOCK_HOLDER() GC_lock_holder = pthread_self()
|
||
|
# define UNSET_LOCK_HOLDER() GC_lock_holder = NO_THREAD
|
||
|
# define I_HOLD_LOCK() (pthread_equal(GC_lock_holder, pthread_self()))
|
||
|
extern VOLATILE GC_bool GC_collecting;
|
||
|
# define ENTER_GC() GC_collecting = 1;
|
||
|
# define EXIT_GC() GC_collecting = 0;
|
||
|
extern void GC_lock(void);
|
||
|
extern pthread_t GC_lock_holder;
|
||
|
# ifdef GC_ASSERTIONS
|
||
|
extern pthread_t GC_mark_lock_holder;
|
||
|
# endif
|
||
|
# endif /* GC_PTHREADS with linux_threads.c implementation */
|
||
|
# if defined(GC_WIN32_THREADS)
|
||
|
# if defined(GC_PTHREADS)
|
||
|
# include <pthread.h>
|
||
|
extern pthread_mutex_t GC_allocate_ml;
|
||
|
# define LOCK() pthread_mutex_lock(&GC_allocate_ml)
|
||
|
# define UNLOCK() pthread_mutex_unlock(&GC_allocate_ml)
|
||
|
# else
|
||
|
# include <windows.h>
|
||
|
GC_API CRITICAL_SECTION GC_allocate_ml;
|
||
|
# define LOCK() EnterCriticalSection(&GC_allocate_ml);
|
||
|
# define UNLOCK() LeaveCriticalSection(&GC_allocate_ml);
|
||
|
# endif
|
||
|
# endif
|
||
|
# ifndef SET_LOCK_HOLDER
|
||
|
# define SET_LOCK_HOLDER()
|
||
|
# define UNSET_LOCK_HOLDER()
|
||
|
# define I_HOLD_LOCK() FALSE
|
||
|
/* Used on platforms were locks can be reacquired, */
|
||
|
/* so it doesn't matter if we lie. */
|
||
|
# endif
|
||
|
# else /* !THREADS */
|
||
|
# define LOCK()
|
||
|
# define UNLOCK()
|
||
|
# endif /* !THREADS */
|
||
|
# ifndef SET_LOCK_HOLDER
|
||
|
# define SET_LOCK_HOLDER()
|
||
|
# define UNSET_LOCK_HOLDER()
|
||
|
# define I_HOLD_LOCK() FALSE
|
||
|
/* Used on platforms were locks can be reacquired, */
|
||
|
/* so it doesn't matter if we lie. */
|
||
|
# endif
|
||
|
# ifndef ENTER_GC
|
||
|
# define ENTER_GC()
|
||
|
# define EXIT_GC()
|
||
|
# endif
|
||
|
|
||
|
# ifndef DCL_LOCK_STATE
|
||
|
# define DCL_LOCK_STATE
|
||
|
# endif
|
||
|
# ifndef FASTLOCK
|
||
|
# define FASTLOCK() LOCK()
|
||
|
# define FASTLOCK_SUCCEEDED() TRUE
|
||
|
# define FASTUNLOCK() UNLOCK()
|
||
|
# endif
|
||
|
|
||
|
#endif /* GC_LOCKS_H */
|