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-rw-r--r--sysdeps/unix/sysv/linux/m68k/sysdep.h295
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diff --git a/sysdeps/unix/sysv/linux/m68k/sysdep.h b/sysdeps/unix/sysv/linux/m68k/sysdep.h
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+++ b/sysdeps/unix/sysv/linux/m68k/sysdep.h
@@ -0,0 +1,295 @@
+/* Copyright (C) 1996, 1997, 1998, 2000, 2003, 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Written by Andreas Schwab, <schwab@issan.informatik.uni-dortmund.de>,
+   December 1995.
+
+   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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdeps/unix/sysdep.h>
+#include <sysdeps/m68k/sysdep.h>
+
+/* Defines RTLD_PRIVATE_ERRNO.  */
+#include <dl-sysdep.h>
+
+/* For Linux we can use the system call table in the header file
+	/usr/include/asm/unistd.h
+   of the kernel.  But these symbols do not follow the SYS_* syntax
+   so we have to redefine the `SYS_ify' macro here.  */
+#undef SYS_ify
+#ifdef __STDC__
+# define SYS_ify(syscall_name)	__NR_##syscall_name
+#else
+# define SYS_ify(syscall_name)	__NR_/**/syscall_name
+#endif
+
+#ifdef __ASSEMBLER__
+
+/* Linux uses a negative return value to indicate syscall errors, unlike
+   most Unices, which use the condition codes' carry flag.
+
+   Since version 2.1 the return value of a system call might be negative
+   even if the call succeeded.  E.g., the `lseek' system call might return
+   a large offset.  Therefore we must not anymore test for < 0, but test
+   for a real error by making sure the value in %d0 is a real error
+   number.  Linus said he will make sure the no syscall returns a value
+   in -1 .. -4095 as a valid result so we can savely test with -4095.  */
+
+/* We don't want the label for the error handler to be visible in the symbol
+   table when we define it here.  */
+#ifdef PIC
+#define SYSCALL_ERROR_LABEL .Lsyscall_error
+#else
+#define SYSCALL_ERROR_LABEL __syscall_error
+#endif
+
+#undef PSEUDO
+#define	PSEUDO(name, syscall_name, args)				      \
+  .text;								      \
+  ENTRY (name)								      \
+    DO_CALL (syscall_name, args);					      \
+    cmp.l &-4095, %d0;							      \
+    jcc SYSCALL_ERROR_LABEL
+
+#undef PSEUDO_END
+#define PSEUDO_END(name)						      \
+  SYSCALL_ERROR_HANDLER;						      \
+  END (name)
+
+#undef PSEUDO_NOERRNO
+#define	PSEUDO_NOERRNO(name, syscall_name, args)			      \
+  .text;								      \
+  ENTRY (name)								      \
+    DO_CALL (syscall_name, args)
+
+#undef PSEUDO_END_NOERRNO
+#define PSEUDO_END_NOERRNO(name)					      \
+  END (name)
+
+#define ret_NOERRNO rts
+
+/* The function has to return the error code.  */
+#undef	PSEUDO_ERRVAL
+#define	PSEUDO_ERRVAL(name, syscall_name, args) \
+  .text;								      \
+  ENTRY (name)								      \
+    DO_CALL (syscall_name, args);					      \
+    negl %d0
+
+#undef	PSEUDO_END_ERRVAL
+#define	PSEUDO_END_ERRVAL(name) \
+  END (name)
+
+#define ret_ERRVAL rts
+
+#ifdef PIC
+# if RTLD_PRIVATE_ERRNO
+#  define SYSCALL_ERROR_HANDLER						      \
+SYSCALL_ERROR_LABEL:							      \
+    lea (rtld_errno, %pc), %a0;					      	      \
+    neg.l %d0;								      \
+    move.l %d0, (%a0);							      \
+    move.l &-1, %d0;							      \
+    /* Copy return value to %a0 for syscalls that are declared to return      \
+       a pointer (e.g., mmap).  */					      \
+    move.l %d0, %a0;							      \
+    rts;
+# else /* !RTLD_PRIVATE_ERRNO */
+/* Store (- %d0) into errno through the GOT.  */
+#  if defined _LIBC_REENTRANT
+#   define SYSCALL_ERROR_HANDLER					      \
+SYSCALL_ERROR_LABEL:							      \
+    neg.l %d0;								      \
+    move.l %d0, -(%sp);							      \
+    jbsr __errno_location@PLTPC;					      \
+    move.l (%sp)+, (%a0);						      \
+    move.l &-1, %d0;							      \
+    /* Copy return value to %a0 for syscalls that are declared to return      \
+       a pointer (e.g., mmap).  */					      \
+    move.l %d0, %a0;							      \
+    rts;
+#  else /* !_LIBC_REENTRANT */
+#   define SYSCALL_ERROR_HANDLER					      \
+SYSCALL_ERROR_LABEL:							      \
+    move.l (errno@GOTPC, %pc), %a0;					      \
+    neg.l %d0;								      \
+    move.l %d0, (%a0);							      \
+    move.l &-1, %d0;							      \
+    /* Copy return value to %a0 for syscalls that are declared to return      \
+       a pointer (e.g., mmap).  */					      \
+    move.l %d0, %a0;							      \
+    rts;
+#  endif /* _LIBC_REENTRANT */
+# endif /* RTLD_PRIVATE_ERRNO */
+#else
+# define SYSCALL_ERROR_HANDLER	/* Nothing here; code in sysdep.S is used.  */
+#endif /* PIC */
+
+/* Linux takes system call arguments in registers:
+
+	syscall number	%d0	     call-clobbered
+	arg 1		%d1	     call-clobbered
+	arg 2		%d2	     call-saved
+	arg 3		%d3	     call-saved
+	arg 4		%d4	     call-saved
+	arg 5		%d5	     call-saved
+
+   The stack layout upon entering the function is:
+
+	20(%sp)		Arg# 5
+	16(%sp)		Arg# 4
+	12(%sp)		Arg# 3
+	 8(%sp)		Arg# 2
+	 4(%sp)		Arg# 1
+	  (%sp)		Return address
+
+   (Of course a function with say 3 arguments does not have entries for
+   arguments 4 and 5.)
+
+   Separate move's are faster than movem, but need more space.  Since
+   speed is more important, we don't use movem.  Since %a0 and %a1 are
+   scratch registers, we can use them for saving as well.  */
+
+#define DO_CALL(syscall_name, args)			      		      \
+    move.l &SYS_ify(syscall_name), %d0;					      \
+    DOARGS_##args							      \
+    trap &0;								      \
+    UNDOARGS_##args
+
+#define	DOARGS_0	/* No arguments to frob.  */
+#define	UNDOARGS_0	/* No arguments to unfrob.  */
+#define	_DOARGS_0(n)	/* No arguments to frob.  */
+
+#define	DOARGS_1	_DOARGS_1 (4)
+#define	_DOARGS_1(n)	move.l n(%sp), %d1; _DOARGS_0 (n)
+#define	UNDOARGS_1	UNDOARGS_0
+
+#define	DOARGS_2	_DOARGS_2 (8)
+#define	_DOARGS_2(n)	move.l %d2, %a0; move.l n(%sp), %d2; _DOARGS_1 (n-4)
+#define	UNDOARGS_2	UNDOARGS_1; move.l %a0, %d2
+
+#define DOARGS_3	_DOARGS_3 (12)
+#define _DOARGS_3(n)	move.l %d3, %a1; move.l n(%sp), %d3; _DOARGS_2 (n-4)
+#define UNDOARGS_3	UNDOARGS_2; move.l %a1, %d3
+
+#define DOARGS_4	_DOARGS_4 (16)
+#define _DOARGS_4(n)	move.l %d4, -(%sp); move.l n+4(%sp), %d4; _DOARGS_3 (n)
+#define UNDOARGS_4	UNDOARGS_3; move.l (%sp)+, %d4
+
+#define DOARGS_5	_DOARGS_5 (20)
+#define _DOARGS_5(n)	move.l %d5, -(%sp); move.l n+4(%sp), %d5; _DOARGS_4 (n)
+#define UNDOARGS_5	UNDOARGS_4; move.l (%sp)+, %d5
+
+
+#define	ret	rts
+#if 0 /* Not used by Linux */
+#define	r0	%d0
+#define	r1	%d1
+#define	MOVE(x,y)	movel x , y
+#endif
+
+#else /* not __ASSEMBLER__ */
+
+/* Define a macro which expands into the inline wrapper code for a system
+   call.  */
+#undef INLINE_SYSCALL
+#define INLINE_SYSCALL(name, nr, args...)				\
+  ({ unsigned int _sys_result = INTERNAL_SYSCALL (name, , nr, args);	\
+     if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (_sys_result, ), 0))\
+       {								\
+	 __set_errno (INTERNAL_SYSCALL_ERRNO (_sys_result, ));		\
+	 _sys_result = (unsigned int) -1;				\
+       }								\
+     (int) _sys_result; })
+
+#undef INTERNAL_SYSCALL_DECL
+#define INTERNAL_SYSCALL_DECL(err) do { } while (0)
+
+/* Define a macro which expands inline into the wrapper code for a system
+   call.  This use is for internal calls that do not need to handle errors
+   normally.  It will never touch errno.  This returns just what the kernel
+   gave back.  */
+#undef INTERNAL_SYSCALL
+#define INTERNAL_SYSCALL(name, err, nr, args...)	\
+  ({ unsigned int _sys_result;				\
+     {							\
+       /* Load argument values in temporary variables
+	  to perform side effects like function calls
+	  before the call used registers are set.  */	\
+       LOAD_ARGS_##nr (args)				\
+       LOAD_REGS_##nr					\
+       register int _d0 asm ("%d0") = __NR_##name;	\
+       asm volatile ("trap #0"				\
+		     : "=d" (_d0)			\
+		     : "0" (_d0) ASM_ARGS_##nr		\
+		     : "memory");			\
+       _sys_result = _d0;				\
+     }							\
+     (int) _sys_result; })
+
+#undef INTERNAL_SYSCALL_ERROR_P
+#define INTERNAL_SYSCALL_ERROR_P(val, err)		\
+  ((unsigned int) (val) >= -4095U)
+
+#undef INTERNAL_SYSCALL_ERRNO
+#define INTERNAL_SYSCALL_ERRNO(val, err)	(-(val))
+
+#define LOAD_ARGS_0()
+#define LOAD_REGS_0
+#define ASM_ARGS_0
+#define LOAD_ARGS_1(a1)				\
+  LOAD_ARGS_0 ()				\
+  int __arg1 = (int) (a1);
+#define LOAD_REGS_1				\
+  register int _d1 asm ("d1") = __arg1;		\
+  LOAD_REGS_0
+#define ASM_ARGS_1	ASM_ARGS_0, "d" (_d1)
+#define LOAD_ARGS_2(a1, a2)			\
+  LOAD_ARGS_1 (a1)				\
+  int __arg2 = (int) (a2);
+#define LOAD_REGS_2				\
+  register int _d2 asm ("d2") = __arg2;		\
+  LOAD_REGS_1
+#define ASM_ARGS_2	ASM_ARGS_1, "d" (_d2)
+#define LOAD_ARGS_3(a1, a2, a3)			\
+  LOAD_ARGS_2 (a1, a2)				\
+  int __arg3 = (int) (a3);
+#define LOAD_REGS_3				\
+  register int _d3 asm ("d3") = __arg3;		\
+  LOAD_REGS_2
+#define ASM_ARGS_3	ASM_ARGS_2, "d" (_d3)
+#define LOAD_ARGS_4(a1, a2, a3, a4)		\
+  LOAD_ARGS_3 (a1, a2, a3)			\
+  int __arg4 = (int) (a4);
+#define LOAD_REGS_4				\
+  register int _d4 asm ("d4") = __arg4;		\
+  LOAD_REGS_3
+#define ASM_ARGS_4	ASM_ARGS_3, "d" (_d4)
+#define LOAD_ARGS_5(a1, a2, a3, a4, a5)		\
+  LOAD_ARGS_4 (a1, a2, a3, a4)			\
+  int __arg5 = (int) (a5);
+#define LOAD_REGS_5				\
+  register int _d5 asm ("d5") = __arg5;		\
+  LOAD_REGS_4
+#define ASM_ARGS_5	ASM_ARGS_4, "d" (_d5)
+#define LOAD_ARGS_6(a1, a2, a3, a4, a5, a6)	\
+  LOAD_ARGS_5 (a1, a2, a3, a4, a5)		\
+  int __arg6 = (int) (a6);
+#define LOAD_REGS_6				\
+  register int _a0 asm ("a0") = __arg6;		\
+  LOAD_REGS_5
+#define ASM_ARGS_6	ASM_ARGS_5, "a" (_a0)
+
+#endif /* not __ASSEMBLER__ */