config.gcc (arm-wrs-vxworks*): Rework to handle arm-wrs-vxworks7 as well as arm-wrs...

config.gcc (arm-wrs-vxworks*): Rework to handle arm-wrs-vxworks7 as well as arm-wrs-vxworks.

2017-08-01  Jerome Lambourg  <lambourg@adacore.com>
           Doug Rupp  <rupp@adacore.com>
           Olivier Hainque  <hainque@adacore.com>

  	gcc/
   	* config.gcc (arm-wrs-vxworks*): Rework to handle arm-wrs-vxworks7 as
   	well as arm-wrs-vxworks. Update target_cpu_name from arm6 (arch v3) to
   	arm8 (arch v4).
   	* config/arm/vxworks.h (MAYBE_TARGET_BPABI_CPP_BUILTINS): New, helper
   	for TARGET_OS_CPP_BUILTIN.
   	(TARGET_OS_CPP_BUILTIN): Invoke MAYBE_TARGET_BPABI_CPP_BUILTINS(),
   	refine CPU definitions for arm_arch5 and add those for arm_arch6 and
   	arm_arch7.
    	(MAYBE_ASM_ABI_SPEC): New, helper for SUBTARGET_EXTRA_ASM_SPEC,
   	passing required abi options to the assembler for EABI configurations.
   	(EXTRA_CC1_SPEC): New macro, to help prevent the implicit production
   	of .text.hot and .text.unlikely sections for kernel modules when
   	using ARM style exceptions.
   	(CC1_SPEC): Remove obsolete attempt at mimicking Diab toolchain
   	options. Add EXTRA_CC1_SPEC.
   	(VXWORKS_ENDIAN_SPEC): Adjust comment and remove handling of Diab
   	toolchain options.
   	(DWARF2_UNWIND_INFO): Redefine to handle the pre/post VxWorks 7
   	transition.
   	(ARM_TARGET2_DWARF_FORMAT): Define.
   	* config/arm/t-vxworks: Adjust multilib control to removal of the
   	Diab command line options.

   	libgcc/
   	* config.host (arm-wrs-vxworks*): Rework to handle arm-wrs-vxworks7
   	as well as arm-wrs-vxworks.
   	* config/arm/t-vxworks7: New file.  Add unwind-arm-vxworks.c to
   	LIB2ADDEH.
   	* config/arm/unwind-arm-vxworks.c: New file. Provide dummy
   	__exidx_start and __exidx_end for downloadable modules.

Co-Authored-By: Doug Rupp <rupp@adacore.com>
Co-Authored-By: Olivier Hainque <hainque@adacore.com>
From-SVN: r250781