linux-atomic.c: New file.

        * pa/linux-atomic.c: New file.
	* pa/t-linux (LIB2FUNCS_STATIC_EXTRA): Define.
	* pa/t-linux64 (LIB2FUNCS_STATIC_EXTRA): Define.

From-SVN: r140091

gcc/ChangeLog

+2008-09-07  Helge Deller  <deller@gmx.de>
+
+        * pa/linux-atomic.c: New file.
+	* pa/t-linux (LIB2FUNCS_STATIC_EXTRA): Define.
+	* pa/t-linux64 (LIB2FUNCS_STATIC_EXTRA): Define.
+
 2008-09-07  Richard Guenther  <rguenther@suse.de>
             Ira Rosen  <irar@il.ibm.com>
 

gcc/config/pa/linux-atomic.c

+/* Linux-specific atomic operations for PA Linux.
+   Copyright (C) 2008 Free Software Foundation, Inc.
+   Based on code contributed by CodeSourcery for ARM EABI Linux.
+   Modifications for PA Linux by Helge Deller <deller@gmx.de>
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file.  (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+GCC 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 General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING.  If not, write to the Free
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA.  */
+
+#include <errno.h>
+
+/* All PA-RISC implementations supported by linux have strongly
+   ordered loads and stores.  Only cache flushes and purges can be
+   delayed.  The data cache implementations are all globally
+   coherent.  Thus, there is no need to synchonize memory accesses.
+
+   GCC automatically issues a asm memory barrier when it encounters
+   a __sync_synchronize builtin.  Thus, we do not need to define this
+   builtin.
+
+   We implement byte, short and int versions of each atomic operation
+   using the kernel helper defined below.  There is no support for
+   64-bit operations yet.  */
+
+/* A privileged instruction to crash a userspace program with SIGILL.  */
+#define ABORT_INSTRUCTION asm ("iitlbp %r0,(%sr0, %r0)")
+
+/* Determine kernel LWS function call (0=32-bit, 1=64-bit userspace).  */
+#define LWS_CAS (sizeof(unsigned long) == 4 ? 0 : 1)
+
+/* Kernel helper for compare-and-exchange a 32-bit value.  */
+static inline long
+__kernel_cmpxchg (int oldval, int newval, int *mem)
+{
+  register unsigned long lws_mem asm("r26") = (unsigned long) (mem);
+  register long lws_ret   asm("r28");
+  register long lws_errno asm("r21");
+  register int lws_old asm("r25") = oldval;
+  register int lws_new asm("r24") = newval;
+  asm volatile (	"ble	0xb0(%%sr2, %%r0)	\n\t"
+			"ldi	%5, %%r20		\n\t"
+	: "=r" (lws_ret), "=r" (lws_errno), "=r" (lws_mem),
+	  "=r" (lws_old), "=r" (lws_new)
+	: "i" (LWS_CAS), "2" (lws_mem), "3" (lws_old), "4" (lws_new)
+	: "r1", "r20", "r22", "r23", "r29", "r31", "memory"
+  );
+  if (__builtin_expect (lws_errno == -EFAULT || lws_errno == -ENOSYS, 0))
+    ABORT_INSTRUCTION;
+  return lws_errno;
+}
+
+#define HIDDEN __attribute__ ((visibility ("hidden")))
+
+/* Big endian masks  */
+#define INVERT_MASK_1 24
+#define INVERT_MASK_2 16
+
+#define MASK_1 0xffu
+#define MASK_2 0xffffu
+
+#define FETCH_AND_OP_WORD(OP, PFX_OP, INF_OP)				\
+  int HIDDEN								\
+  __sync_fetch_and_##OP##_4 (int *ptr, int val)				\
+  {									\
+    int failure, tmp;							\
+									\
+    do {								\
+      tmp = *ptr;							\
+      failure = __kernel_cmpxchg (tmp, PFX_OP tmp INF_OP val, ptr);	\
+    } while (failure != 0);						\
+									\
+    return tmp;								\
+  }
+
+FETCH_AND_OP_WORD (add,   , +)
+FETCH_AND_OP_WORD (sub,   , -)
+FETCH_AND_OP_WORD (or,    , |)
+FETCH_AND_OP_WORD (and,   , &)
+FETCH_AND_OP_WORD (xor,   , ^)
+FETCH_AND_OP_WORD (nand, ~, &)
+
+#define NAME_oldval(OP, WIDTH) __sync_fetch_and_##OP##_##WIDTH
+#define NAME_newval(OP, WIDTH) __sync_##OP##_and_fetch_##WIDTH
+
+/* Implement both __sync_<op>_and_fetch and __sync_fetch_and_<op> for
+   subword-sized quantities.  */
+
+#define SUBWORD_SYNC_OP(OP, PFX_OP, INF_OP, TYPE, WIDTH, RETURN)	\
+  TYPE HIDDEN								\
+  NAME##_##RETURN (OP, WIDTH) (TYPE *ptr, TYPE val)			\
+  {									\
+    int *wordptr = (int *) ((unsigned long) ptr & ~3);			\
+    unsigned int mask, shift, oldval, newval;				\
+    int failure;							\
+									\
+    shift = (((unsigned long) ptr & 3) << 3) ^ INVERT_MASK_##WIDTH;	\
+    mask = MASK_##WIDTH << shift;					\
+									\
+    do {								\
+      oldval = *wordptr;						\
+      newval = ((PFX_OP ((oldval & mask) >> shift)			\
+                 INF_OP (unsigned int) val) << shift) & mask;		\
+      newval |= oldval & ~mask;						\
+      failure = __kernel_cmpxchg (oldval, newval, wordptr);		\
+    } while (failure != 0);						\
+									\
+    return (RETURN & mask) >> shift;					\
+  }
+
+SUBWORD_SYNC_OP (add,   , +, short, 2, oldval)
+SUBWORD_SYNC_OP (sub,   , -, short, 2, oldval)
+SUBWORD_SYNC_OP (or,    , |, short, 2, oldval)
+SUBWORD_SYNC_OP (and,   , &, short, 2, oldval)
+SUBWORD_SYNC_OP (xor,   , ^, short, 2, oldval)
+SUBWORD_SYNC_OP (nand, ~, &, short, 2, oldval)
+
+SUBWORD_SYNC_OP (add,   , +, char, 1, oldval)
+SUBWORD_SYNC_OP (sub,   , -, char, 1, oldval)
+SUBWORD_SYNC_OP (or,    , |, char, 1, oldval)
+SUBWORD_SYNC_OP (and,   , &, char, 1, oldval)
+SUBWORD_SYNC_OP (xor,   , ^, char, 1, oldval)
+SUBWORD_SYNC_OP (nand, ~, &, char, 1, oldval)
+
+#define OP_AND_FETCH_WORD(OP, PFX_OP, INF_OP)				\
+  int HIDDEN								\
+  __sync_##OP##_and_fetch_4 (int *ptr, int val)				\
+  {									\
+    int tmp, failure;							\
+									\
+    do {								\
+      tmp = *ptr;							\
+      failure = __kernel_cmpxchg (tmp, PFX_OP tmp INF_OP val, ptr);	\
+    } while (failure != 0);						\
+									\
+    return PFX_OP tmp INF_OP val;					\
+  }
+
+OP_AND_FETCH_WORD (add,   , +)
+OP_AND_FETCH_WORD (sub,   , -)
+OP_AND_FETCH_WORD (or,    , |)
+OP_AND_FETCH_WORD (and,   , &)
+OP_AND_FETCH_WORD (xor,   , ^)
+OP_AND_FETCH_WORD (nand, ~, &)
+
+SUBWORD_SYNC_OP (add,   , +, short, 2, newval)
+SUBWORD_SYNC_OP (sub,   , -, short, 2, newval)
+SUBWORD_SYNC_OP (or,    , |, short, 2, newval)
+SUBWORD_SYNC_OP (and,   , &, short, 2, newval)
+SUBWORD_SYNC_OP (xor,   , ^, short, 2, newval)
+SUBWORD_SYNC_OP (nand, ~, &, short, 2, newval)
+
+SUBWORD_SYNC_OP (add,   , +, char, 1, newval)
+SUBWORD_SYNC_OP (sub,   , -, char, 1, newval)
+SUBWORD_SYNC_OP (or,    , |, char, 1, newval)
+SUBWORD_SYNC_OP (and,   , &, char, 1, newval)
+SUBWORD_SYNC_OP (xor,   , ^, char, 1, newval)
+SUBWORD_SYNC_OP (nand, ~, &, char, 1, newval)
+
+int HIDDEN
+__sync_val_compare_and_swap_4 (int *ptr, int oldval, int newval)
+{
+  int actual_oldval, fail;
+    
+  while (1)
+    {
+      actual_oldval = *ptr;
+
+      if (oldval != actual_oldval)
+	return actual_oldval;
+
+      fail = __kernel_cmpxchg (actual_oldval, newval, ptr);
+  
+      if (!fail)
+	return oldval;
+    }
+}
+
+#define SUBWORD_VAL_CAS(TYPE, WIDTH)					\
+  TYPE HIDDEN								\
+  __sync_val_compare_and_swap_##WIDTH (TYPE *ptr, TYPE oldval,		\
+				       TYPE newval)			\
+  {									\
+    int *wordptr = (int *)((unsigned long) ptr & ~3), fail;		\
+    unsigned int mask, shift, actual_oldval, actual_newval;		\
+									\
+    shift = (((unsigned long) ptr & 3) << 3) ^ INVERT_MASK_##WIDTH;	\
+    mask = MASK_##WIDTH << shift;					\
+									\
+    while (1)								\
+      {									\
+	actual_oldval = *wordptr;					\
+									\
+	if (((actual_oldval & mask) >> shift) != (unsigned int) oldval)	\
+          return (actual_oldval & mask) >> shift;			\
+									\
+	actual_newval = (actual_oldval & ~mask)				\
+			| (((unsigned int) newval << shift) & mask);	\
+									\
+	fail = __kernel_cmpxchg (actual_oldval, actual_newval,		\
+				 wordptr);				\
+									\
+	if (!fail)							\
+	  return oldval;						\
+      }									\
+  }
+
+SUBWORD_VAL_CAS (short, 2)
+SUBWORD_VAL_CAS (char,  1)
+
+typedef unsigned char bool;
+
+bool HIDDEN
+__sync_bool_compare_and_swap_4 (int *ptr, int oldval, int newval)
+{
+  int failure = __kernel_cmpxchg (oldval, newval, ptr);
+  return (failure == 0);
+}
+
+#define SUBWORD_BOOL_CAS(TYPE, WIDTH)					\
+  bool HIDDEN								\
+  __sync_bool_compare_and_swap_##WIDTH (TYPE *ptr, TYPE oldval,		\
+					TYPE newval)			\
+  {									\
+    TYPE actual_oldval							\
+      = __sync_val_compare_and_swap_##WIDTH (ptr, oldval, newval);	\
+    return (oldval == actual_oldval);					\
+  }
+
+SUBWORD_BOOL_CAS (short, 2)
+SUBWORD_BOOL_CAS (char,  1)
+
+int HIDDEN
+__sync_lock_test_and_set_4 (int *ptr, int val)
+{
+  int failure, oldval;
+
+  do {
+    oldval = *ptr;
+    failure = __kernel_cmpxchg (oldval, val, ptr);
+  } while (failure != 0);
+
+  return oldval;
+}
+
+#define SUBWORD_TEST_AND_SET(TYPE, WIDTH)				\
+  TYPE HIDDEN								\
+  __sync_lock_test_and_set_##WIDTH (TYPE *ptr, TYPE val)		\
+  {									\
+    int failure;							\
+    unsigned int oldval, newval, shift, mask;				\
+    int *wordptr = (int *) ((unsigned long) ptr & ~3);			\
+									\
+    shift = (((unsigned long) ptr & 3) << 3) ^ INVERT_MASK_##WIDTH;	\
+    mask = MASK_##WIDTH << shift;					\
+									\
+    do {								\
+      oldval = *wordptr;						\
+      newval = (oldval & ~mask)						\
+	       | (((unsigned int) val << shift) & mask);		\
+      failure = __kernel_cmpxchg (oldval, newval, wordptr);		\
+    } while (failure != 0);						\
+									\
+    return (oldval & mask) >> shift;					\
+  }
+
+SUBWORD_TEST_AND_SET (short, 2)
+SUBWORD_TEST_AND_SET (char,  1)
+
+#define SYNC_LOCK_RELEASE(TYPE, WIDTH)					\
+  void HIDDEN								\
+  __sync_lock_release_##WIDTH (TYPE *ptr)				\
+  {									\
+    *ptr = 0;								\
+  }
+
+SYNC_LOCK_RELEASE (int,   4)
+SYNC_LOCK_RELEASE (short, 2)
+SYNC_LOCK_RELEASE (char,  1)

gcc/config/pa/t-linux

@@ -9,6 +9,7 @@ LIB1ASMSRC = pa/milli64.S
 TARGET_LIBGCC2_CFLAGS = -fPIC -DELF=1 -DLINUX=1
 
 LIB2FUNCS_EXTRA=fptr.c
+LIB2FUNCS_STATIC_EXTRA = $(srcdir)/config/pa/linux-atomic.c
 
 fptr.c: $(srcdir)/config/pa/fptr.c
 	rm -f fptr.c

gcc/config/pa/t-linux64

@@ -8,5 +8,7 @@ LIB1ASMSRC = pa/milli64.S
 # Actually, hppa64 is always PIC but adding -fPIC does no harm.
 CRTSTUFF_T_CFLAGS_S = -fPIC
 
+LIB2FUNCS_STATIC_EXTRA = $(srcdir)/config/pa/linux-atomic.c
+
 # Compile libgcc2.a as PIC.
 TARGET_LIBGCC2_CFLAGS = -fPIC -Dpa64=1 -DELF=1