linuxthreads/sysdeps/sparc/sparc64/pt-machine.h

   1 /* Machine-dependent pthreads configuration and inline functions.
   2    Sparc v9 version.
   3    Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5    Contributed by Richard Henderson <rth@tamu.edu>.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Library General Public License as
   9    published by the Free Software Foundation; either version 2 of the
  10    License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Library General Public License for more details.
  16
  17    You should have received a copy of the GNU Library General Public
  18    License along with the GNU C Library; see the file COPYING.LIB.  If
  19    not, write to the Free Software Foundation, Inc.,
  20    59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  21
  22 #ifndef PT_EI
  23 # define PT_EI extern inline
  24 #endif
  25
  26
  27 /* Spinlock implementation; required.  */
  28 PT_EI int
  29 testandset (int *spinlock)
  30 {
  31   int ret;
  32
  33   __asm__ __volatile__("ldstub %1,%0"
  34         : "=r"(ret), "=m"(*spinlock) : "m"(*spinlock));
  35
  36   return ret;
  37 }
  38
  39
  40 /* Memory barrier; default is to do nothing */
  41 /* FIXME: is stbar OK, or should we use the more general membar instruction?
  42    If so, which mode to pass to membar? */
  43 #define MEMORY_BARRIER() __asm__ __volatile__("stbar" : : : "memory")
  44 /* Write barrier.  */
  45 #define WRITE_MEMORY_BARRIER() \
  46      __asm__ __volatile__("membar #StoreLoad | #StoreStore" : : : "memory")
  47
  48
  49 /* Get some notion of the current stack.  Need not be exactly the top
  50    of the stack, just something somewhere in the current frame.  */
  51 #define CURRENT_STACK_FRAME  stack_pointer
  52 register char *stack_pointer __asm__ ("%sp");
  53
  54
  55 /* Registers %g6 and %g7 are reserved by the ABI for "system use".  It
  56    happens that Solaris uses %g6 for the thread pointer -- we do the same.  */
  57 struct _pthread_descr_struct;
  58 register struct _pthread_descr_struct *__thread_self __asm__("%g6");
  59
  60 /* Return the thread descriptor for the current thread.  */
  61 #define THREAD_SELF  __thread_self
  62
  63 /* Initialize the thread-unique value.  */
  64 #define INIT_THREAD_SELF(descr, nr)  (__thread_self = (descr))
  65
  66
  67 /* Compare-and-swap for semaphores. */
  68
  69 #define HAS_COMPARE_AND_SWAP
  70 PT_EI int
  71 __compare_and_swap (long int *p, long int oldval, long int newval)
  72 {
  73   long int readval;
  74
  75   __asm__ __volatile__ ("casx   [%4], %2, %0"
  76                         : "=r"(readval), "=m"(*p)
  77                         : "r"(oldval), "m"(*p), "r"(p), "0"(newval));
  78   MEMORY_BARRIER();
  79   return readval == oldval;
  80 }
  81
  82 /* Access to data in the thread descriptor is easy.  */
  83 #define THREAD_GETMEM(descr, member) __thread_self->member
  84 #define THREAD_GETMEM_NC(descr, member) __thread_self->member
  85 #define THREAD_SETMEM(descr, member, value) __thread_self->member = (value)
  86 #define THREAD_SETMEM_NC(descr, member, value) __thread_self->member = (value)