libc: Add a common sysdep header

Add a common header file to provide macros useful in asm code:
C_LABEL to construct the asm name for a C symbol
cfi_xxx to generate eh_frame unwind information.

Ported from NPTL branch.

Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>

Rules.mak

@@ -547,6 +547,7 @@ NOSTDLIB_CFLAGS:=$(call check_gcc,-nostdlib,)
 CFLAGS := -include $(top_srcdir)include/libc-symbols.h \
 	$(XWARNINGS) $(CPU_CFLAGS) $(SSP_CFLAGS) \
 	-nostdinc -I$(top_builddir)include -I$(top_srcdir)include -I. \
+	-I$(top_srcdir)libc/sysdeps/linux \
 	-I$(top_srcdir)libc/sysdeps/linux/$(TARGET_ARCH)
 ifneq ($(strip $(UCLIBC_EXTRA_CFLAGS)),"")
 CFLAGS += $(call qstrip,$(UCLIBC_EXTRA_CFLAGS))

libc/sysdeps/linux/common/sysdep.h

@@ -0,0 +1,139 @@
+/* Generic asm macros used on many machines.
+   Copyright (C) 1991,92,93,96,98,2002,2003 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 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 <sys/syscall.h>
+
+#ifndef C_LABEL
+
+/* Define a macro we can use to construct the asm name for a C symbol.  */
+#ifndef	__UCLIBC_UNDERSCORES__
+#ifdef	__STDC__
+#define C_LABEL(name)		name##:
+#else
+#define C_LABEL(name)		name/**/:
+#endif
+#else
+#ifdef	__STDC__
+#define C_LABEL(name)		_##name##:
+#else
+#define C_LABEL(name)		_/**/name/**/:
+#endif
+#endif
+
+#endif
+
+#ifdef __ASSEMBLER__
+/* Mark the end of function named SYM.  This is used on some platforms
+   to generate correct debugging information.  */
+#ifndef END
+#define END(sym)
+#endif
+
+#ifndef JUMPTARGET
+#define JUMPTARGET(sym)		sym
+#endif
+
+/* Macros to generate eh_frame unwind information.  */
+# ifdef HAVE_ASM_CFI_DIRECTIVES
+#  define cfi_startproc			.cfi_startproc
+#  define cfi_endproc			.cfi_endproc
+#  define cfi_def_cfa(reg, off)		.cfi_def_cfa reg, off
+#  define cfi_def_cfa_register(reg)	.cfi_def_cfa_register reg
+#  define cfi_def_cfa_offset(off)	.cfi_def_cfa_offset off
+#  define cfi_adjust_cfa_offset(off)	.cfi_adjust_cfa_offset off
+#  define cfi_offset(reg, off)		.cfi_offset reg, off
+#  define cfi_rel_offset(reg, off)	.cfi_rel_offset reg, off
+#  define cfi_register(r1, r2)		.cfi_register r1, r2
+#  define cfi_return_column(reg)	.cfi_return_column reg
+#  define cfi_restore(reg)		.cfi_restore reg
+#  define cfi_same_value(reg)		.cfi_same_value reg
+#  define cfi_undefined(reg)		.cfi_undefined reg
+#  define cfi_remember_state		.cfi_remember_state
+#  define cfi_restore_state		.cfi_restore_state
+#  define cfi_window_save		.cfi_window_save
+# else
+#  define cfi_startproc
+#  define cfi_endproc
+#  define cfi_def_cfa(reg, off)
+#  define cfi_def_cfa_register(reg)
+#  define cfi_def_cfa_offset(off)
+#  define cfi_adjust_cfa_offset(off)
+#  define cfi_offset(reg, off)
+#  define cfi_rel_offset(reg, off)
+#  define cfi_register(r1, r2)
+#  define cfi_return_column(reg)
+#  define cfi_restore(reg)
+#  define cfi_same_value(reg)
+#  define cfi_undefined(reg)
+#  define cfi_remember_state
+#  define cfi_restore_state
+#  define cfi_window_save
+# endif
+
+#else /* ! ASSEMBLER */
+# ifdef HAVE_ASM_CFI_DIRECTIVES
+#  define CFI_STRINGIFY(Name) CFI_STRINGIFY2 (Name)
+#  define CFI_STRINGIFY2(Name) #Name
+#  define CFI_STARTPROC	".cfi_startproc"
+#  define CFI_ENDPROC	".cfi_endproc"
+#  define CFI_DEF_CFA(reg, off)	\
+   ".cfi_def_cfa " CFI_STRINGIFY(reg) "," CFI_STRINGIFY(off)
+#  define CFI_DEF_CFA_REGISTER(reg) \
+   ".cfi_def_cfa_register " CFI_STRINGIFY(reg)
+#  define CFI_DEF_CFA_OFFSET(off) \
+   ".cfi_def_cfa_offset " CFI_STRINGIFY(off)
+#  define CFI_ADJUST_CFA_OFFSET(off) \
+   ".cfi_adjust_cfa_offset " CFI_STRINGIFY(off)
+#  define CFI_OFFSET(reg, off) \
+   ".cfi_offset " CFI_STRINGIFY(reg) "," CFI_STRINGIFY(off)
+#  define CFI_REL_OFFSET(reg, off) \
+   ".cfi_rel_offset " CFI_STRINGIFY(reg) "," CFI_STRINGIFY(off)
+#  define CFI_REGISTER(r1, r2) \
+   ".cfi_register " CFI_STRINGIFY(r1) "," CFI_STRINGIFY(r2)
+#  define CFI_RETURN_COLUMN(reg) \
+   ".cfi_return_column " CFI_STRINGIFY(reg)
+#  define CFI_RESTORE(reg) \
+   ".cfi_restore " CFI_STRINGIFY(reg)
+#  define CFI_UNDEFINED(reg) \
+   ".cfi_undefined " CFI_STRINGIFY(reg)
+#  define CFI_REMEMBER_STATE \
+   ".cfi_remember_state"
+#  define CFI_RESTORE_STATE \
+   ".cfi_restore_state"
+#  define CFI_WINDOW_SAVE \
+   ".cfi_window_save"
+# else
+#  define CFI_STARTPROC
+#  define CFI_ENDPROC
+#  define CFI_DEF_CFA(reg, off)
+#  define CFI_DEF_CFA_REGISTER(reg)
+#  define CFI_DEF_CFA_OFFSET(off)
+#  define CFI_ADJUST_CFA_OFFSET(off)
+#  define CFI_OFFSET(reg, off)
+#  define CFI_REL_OFFSET(reg, off)
+#  define CFI_REGISTER(r1, r2)
+#  define CFI_RETURN_COLUMN(reg)
+#  define CFI_RESTORE(reg)
+#  define CFI_UNDEFINED(reg)
+#  define CFI_REMEMBER_STATE
+#  define CFI_RESTORE_STATE
+#  define CFI_WINDOW_SAVE
+# endif
+
+#endif /* __ASSEMBLER__ */