Hi Guys,

  I am applying the attached patch to add two new command line options
  to the MSP430 backend.  The -mcode-region= and -mdata-region= options
  allow the user to specify whether functions and data should be placed
  into low memory (below 64K) or high memory.  This only applies to the
  MSP430X, and only when the specific MSP430 part actually has both low
  and high memory regions.

  An interesting ability of this new feature is to select a memory
  region of "either", which tells the linker to place the object into
  low memory if there is room available and into high memory otherwise.

  Three new function and data attributes have also been added - lower,
  either and upper - which allow the programmer to explicitly state
  which memory region an object should use.
  
  Tested with no regressions and 77 less unexpected failures on an
  msp430-elf toolchain.

Cheers
  Nick

gcc/ChangeLog
2015-05-05  Nick Clifton  <nickc@redhat.com>

	* config/msp430/msp430-opts.h (enum msp430_regions): New.
	* config/msp430/msp430.c (msp430_override_options): Complain if
	-mcode-region or -mdata-region is used on a non MSP430X.
	(msp430_section_attr): New function.  Checks lower, upper and
	either attributes.
	(msp430_attribute_table): Add lower, upper and either.
	(gen_prefix): New function.  Generates a prefix for a section
	name.
	(msp430_select_section): New function - handles the choice of
	section for an object.  Takes into account memory region
	attributes and options.
	(msp430_function_section): Use gen_prefix.
	(TARGET_SECTION_TYPE_FLAGS): Define.
	(msp430_section_type_flags): New function.
	(TARGET_ASM_UNIQUE_SECTION): Define.
	(msp430_unique_section): New function.
	(msp430_output_aligned_decl_common): New function.
	(msp430_do_not_relax_short_jumps): New function.
	* config/msp430/msp430.h (USE_SELECT_SECTION_FOR_FUNCTIONS):
	Define.
	(ASM_OUTPUT_ALIGNED_DECL_COMMON): Define.
	* config/msp430/msp430-protos.h
	(msp430_do_not_relax_short_jumps): New prototype.
	(msp430_output_aligned_decl_common): New prototype.
	* config/msp430/msp430.md (length): New attribute.
	(cbranchhi4_real): If msp430_do_not_relax_short_jumps is true
	then use a long code sequence for short jumps.
	* config/msp430/msp430.opt (mcode-region): New.
	(mdata-region): New.
	* doc/invoke.texi: Document new options.
	* doc/extend.texi: Document new attributes.