Use -fbuilding-libgcc for more target macros used in libgcc.

Use -fbuilding-libgcc for more target macros used in libgcc.

gcc/c-family:
	* c-cppbuiltin.c (c_cpp_builtins): Also define
	__LIBGCC_EH_TABLES_CAN_BE_READ_ONLY__,
	__LIBGCC_EH_FRAME_SECTION_NAME__, __LIBGCC_JCR_SECTION_NAME__,
	__LIBGCC_CTORS_SECTION_ASM_OP__, __LIBGCC_DTORS_SECTION_ASM_OP__,
	__LIBGCC_TEXT_SECTION_ASM_OP__, __LIBGCC_INIT_SECTION_ASM_OP__,
	__LIBGCC_INIT_ARRAY_SECTION_ASM_OP__,
	__LIBGCC_STACK_GROWS_DOWNWARD__,
	__LIBGCC_DONT_USE_BUILTIN_SETJMP__,
	__LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__,
	__LIBGCC_DWARF_FRAME_REGISTERS__,
	__LIBGCC_EH_RETURN_STACKADJ_RTX__, __LIBGCC_JMP_BUF_SIZE__,
	__LIBGCC_STACK_POINTER_REGNUM__ and
	__LIBGCC_VTABLE_USES_DESCRIPTORS__ for -fbuilding-libgcc.
	(builtin_define_with_value): Handle backslash-escaping in string
	macro values.

libgcc:
	* Makefile.in (CRTSTUFF_CFLAGS): Add -fbuilding-libgcc.
	* config/aarch64/linux-unwind.h (STACK_POINTER_REGNUM): Change all
	uses to __LIBGCC_STACK_POINTER_REGNUM__.
	(DWARF_ALT_FRAME_RETURN_COLUMN): Change all uses to
	__LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__.
	* config/alpha/vms-unwind.h (DWARF_ALT_FRAME_RETURN_COLUMN):
	Change use to __LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__.
	* config/cr16/unwind-cr16.c (STACK_GROWS_DOWNWARD): Change all
	uses to __LIBGCC_STACK_GROWS_DOWNWARD__.
	(DWARF_FRAME_REGISTERS): Change all uses to
	__LIBGCC_DWARF_FRAME_REGISTERS__.
	(EH_RETURN_STACKADJ_RTX): Change all uses to
	__LIBGCC_EH_RETURN_STACKADJ_RTX__.
	* config/cr16/unwind-dw2.h (DWARF_FRAME_REGISTERS): Change use to
	__LIBGCC_DWARF_FRAME_REGISTERS__.  Remove conditional definition.
	* config/i386/cygming-crtbegin.c (EH_FRAME_SECTION_NAME): Change
	use to __LIBGCC_EH_FRAME_SECTION_NAME__.
	(JCR_SECTION_NAME): Change use to __LIBGCC_JCR_SECTION_NAME__.
	* config/i386/cygming-crtend.c (EH_FRAME_SECTION_NAME): Change use
	to __LIBGCC_EH_FRAME_SECTION_NAME__.
	(JCR_SECTION_NAME): Change use to __LIBGCC_JCR_SECTION_NAME__
	* config/mips/linux-unwind.h (STACK_POINTER_REGNUM): Change use to
	__LIBGCC_STACK_POINTER_REGNUM__.
	(DWARF_ALT_FRAME_RETURN_COLUMN): Change all uses to
	__LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__.
	* config/nios2/linux-unwind.h (STACK_POINTER_REGNUM): Change use
	to __LIBGCC_STACK_POINTER_REGNUM__.
	* config/pa/hpux-unwind.h (DWARF_ALT_FRAME_RETURN_COLUMN): Change
	all uses to __LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__.
	* config/pa/linux-unwind.h (DWARF_ALT_FRAME_RETURN_COLUMN): Change
	all uses to __LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__.
	* config/rs6000/aix-unwind.h (DWARF_ALT_FRAME_RETURN_COLUMN):
	Change all uses to __LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__.
	(STACK_POINTER_REGNUM): Change all uses to
	__LIBGCC_STACK_POINTER_REGNUM__.
	* config/rs6000/darwin-fallback.c (STACK_POINTER_REGNUM): Change
	use to __LIBGCC_STACK_POINTER_REGNUM__.
	* config/rs6000/linux-unwind.h (STACK_POINTER_REGNUM): Change all
	uses to __LIBGCC_STACK_POINTER_REGNUM__.
	* config/sparc/linux-unwind.h (DWARF_FRAME_REGISTERS): Change use
	to __LIBGCC_DWARF_FRAME_REGISTERS__.
	* config/sparc/sol2-unwind.h (DWARF_FRAME_REGISTERS): Change use
	to __LIBGCC_DWARF_FRAME_REGISTERS__.
	* config/tilepro/linux-unwind.h (STACK_POINTER_REGNUM): Change use
	to __LIBGCC_STACK_POINTER_REGNUM__.
	* config/xtensa/unwind-dw2-xtensa.h (DWARF_FRAME_REGISTERS):
	Remove conditional definition.
	* crtstuff.c (TEXT_SECTION_ASM_OP): Change all uses to
	__LIBGCC_TEXT_SECTION_ASM_OP__.
	(EH_FRAME_SECTION_NAME): Change all uses to
	__LIBGCC_EH_FRAME_SECTION_NAME__.
	(EH_TABLES_CAN_BE_READ_ONLY): Change all uses to
	__LIBGCC_EH_TABLES_CAN_BE_READ_ONLY__.
	(CTORS_SECTION_ASM_OP): Change all uses to
	__LIBGCC_CTORS_SECTION_ASM_OP__.
	(DTORS_SECTION_ASM_OP): Change all uses to
	__LIBGCC_DTORS_SECTION_ASM_OP__.
	(JCR_SECTION_NAME): Change all uses to
	__LIBGCC_JCR_SECTION_NAME__.
	(INIT_SECTION_ASM_OP): Change all uses to
	__LIBGCC_INIT_SECTION_ASM_OP__.
	(INIT_ARRAY_SECTION_ASM_OP): Change all uses to
	__LIBGCC_INIT_ARRAY_SECTION_ASM_OP__.
	* generic-morestack.c (STACK_GROWS_DOWNWARD): Change all uses to
	__LIBGCC_STACK_GROWS_DOWNWARD__.
	* libgcc2.c (INIT_SECTION_ASM_OP): Change all uses to
	__LIBGCC_INIT_SECTION_ASM_OP__.
	(INIT_ARRAY_SECTION_ASM_OP): Change all uses to
	__LIBGCC_INIT_ARRAY_SECTION_ASM_OP__.
	(EH_FRAME_SECTION_NAME): Change all uses to
	__LIBGCC_EH_FRAME_SECTION_NAME__.
	* libgcov-profiler.c (VTABLE_USES_DESCRIPTORS): Remove conditional
	definitions.  Change all uses to
	__LIBGCC_VTABLE_USES_DESCRIPTORS__.
	* unwind-dw2.c (STACK_GROWS_DOWNWARD): Change all uses to
	__LIBGCC_STACK_GROWS_DOWNWARD__.
	(DWARF_FRAME_REGISTERS): Change all uses to
	__LIBGCC_DWARF_FRAME_REGISTERS__.
	(EH_RETURN_STACKADJ_RTX): Change all uses to
	__LIBGCC_EH_RETURN_STACKADJ_RTX__.
	* unwind-dw2.h (DWARF_FRAME_REGISTERS): Remove conditional
	definition.  Change use to __LIBGCC_DWARF_FRAME_REGISTERS__.
	* unwind-sjlj.c (DONT_USE_BUILTIN_SETJMP): Change all uses to
	__LIBGCC_DONT_USE_BUILTIN_SETJMP__.
	(JMP_BUF_SIZE): Change use to __LIBGCC_JMP_BUF_SIZE__.

From-SVN: r214954