glibc/sysdeps/unix/sysv/linux/powerpc/sysdep.h

/* Copyright (C) 1992, 1997, 1998 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
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <sysdeps/unix/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

/* This seems to always be the case on PPC.  */
#define ALIGNARG(log2) log2
/* For ELF we need the `.type' directive to make shared libs work right.  */
#define ASM_TYPE_DIRECTIVE(name,typearg) .type name,typearg;
#define ASM_SIZE_DIRECTIVE(name) .size name,.-name

/* If compiled for profiling, call `_mcount' at the start of each function.  */
#ifdef	PROF
/* The mcount code relies on a the return address being on the stack
   to locate our caller and so it can restore it; so store one just
   for its benefit.  */
#ifdef PIC
#define CALL_MCOUNT							      \
  .pushsection;								      \
  .section ".data";    							      \
  .align ALIGNARG(2);							      \
0:.long 0;								      \
  .previous;								      \
  mflr  %r0;								      \
  stw   %r0,4(%r1);	       						      \
  bl    _GLOBAL_OFFSET_TABLE_@local-4;					      \
  mflr  %r11;								      \
  lwz   %r0,0b@got(%r11);						      \
  bl    JUMPTARGET(_mcount);
#else  /* PIC */
#define CALL_MCOUNT							      \
  .section ".data";							      \
  .align ALIGNARG(2);							      \
0:.long 0;								      \
  .previous;								      \
  mflr  %r0;								      \
  lis   %r11,0b@ha;		       					      \
  stw   %r0,4(%r1);	       						      \
  addi  %r0,%r11,0b@l;							      \
  bl    JUMPTARGET(_mcount);
#endif /* PIC */
#else  /* PROF */
#define CALL_MCOUNT		/* Do nothing.  */
#endif /* PROF */

#define	ENTRY(name)							      \
  ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name);				      \
  ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),@function)			      \
  .align ALIGNARG(2);							      \
  C_LABEL(name)								      \
  CALL_MCOUNT

#define EALIGN_W_0  /* No words to insert.  */
#define EALIGN_W_1  nop
#define EALIGN_W_2  nop;nop
#define EALIGN_W_3  nop;nop;nop
#define EALIGN_W_4  EALIGN_W_3;nop
#define EALIGN_W_5  EALIGN_W_4;nop
#define EALIGN_W_6  EALIGN_W_5;nop
#define EALIGN_W_7  EALIGN_W_6;nop

/* EALIGN is like ENTRY, but does alignment to 'words'*4 bytes
   past a 2^align boundary.  */
#ifdef PROF
#define EALIGN(name, alignt, words)					      \
  ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name);				      \
  ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),@function)			      \
  .align ALIGNARG(2);							      \
  C_LABEL(name)								      \
  CALL_MCOUNT								      \
  b 0f;									      \
  .align ALIGNARG(alignt);						      \
  EALIGN_W_##words;							      \
  0:
#else /* PROF */
#define EALIGN(name, alignt, words)					      \
  ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name);				      \
  ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),@function)			      \
  .align ALIGNARG(alignt);						      \
  EALIGN_W_##words;							      \
  C_LABEL(name)
#endif

#undef	END
#define END(name)							      \
  ASM_SIZE_DIRECTIVE(name)

#define DO_CALL(syscall)				      		      \
    li 0,syscall;						              \
    sc

#ifdef PIC
#define JUMPTARGET(name) name##@plt
#else
#define JUMPTARGET(name) name
#endif

#define PSEUDO(name, syscall_name, args)				      \
  .section ".text";							      \
  ENTRY (name)								      \
    DO_CALL (SYS_ify (syscall_name));

#define PSEUDO_RET							      \
    bnslr;								      \
    b JUMPTARGET(__syscall_error)
#define ret PSEUDO_RET

#undef	PSEUDO_END
#define	PSEUDO_END(name)						      \
  END (name)

/* Local labels stripped out by the linker.  */
#undef L
#define L(x) .L##x

#endif	/* ASSEMBLER */