Add support for new functionality in the msp430 backend of GCC.

This functionality will generate a new GNU object attribute for the "data region"
has been added. This object attribute is used
mark whether the compiler has generated code assuming that data could be in the
upper or lower memory regions.

Code which assumes data is always in the lower memory region is incompatible
with code which uses the full memory range for data.

The patch also adds a new assembler directive ".mspabi_attribute" to handle the
existing MSPABI object attributes. GCC will now emit both .gnu_attribute and
.mspabi_attribute directives to indicate what options the source file was
compiled with.

The assembler will now check the values set in these directives against the
options that the it has been invoked with. If there is a discrepancy, the
assembler will exit with an error.

bfd	* elf32-msp430.c (elf32_msp430_merge_mspabi_attributes): Rename to..
	(elf32_msp430_merge_msp430_attributes): Add support for merging the GNU
	object attribute for data region.

binutils* readelf.c (display_msp430_gnu_attribute): New.
	(process_arch_specific): Use msp430 specific handler for GNU
	attributes.

gas	* config/tc-msp430.c (md_parse_option): Set lower_data_region_only to
	FALSE if the data region is set to "upper", "either" or "none".
	(msp430_object_attribute): New.
	(md_pseudo_table): Handle .mspabi_attribute and .gnu_attribute.
	(msp430_md_end): Replace hard-coded attribute values with enums.
	Handle data region object attribute.
	* doc/as.texi: Document MSP430 Data Region object attribute.
	* doc/c-msp430.texi: Document the .mspabi_attribute directive.
	* testsuite/gas/msp430/attr-430-small-bad.d: New test.
	* testsuite/gas/msp430/attr-430-small-bad.l: New test.
	* testsuite/gas/msp430/attr-430-small-good.d: New test.
	* testsuite/gas/msp430/attr-430-small.s: New test.
	* testsuite/gas/msp430/attr-430x-large-any-bad.d: New test.
	* testsuite/gas/msp430/attr-430x-large-any-bad.l: New test.
	* testsuite/gas/msp430/attr-430x-large-any-good.d: New test.
	* testsuite/gas/msp430/attr-430x-large-any.s: New test.
	* testsuite/gas/msp430/attr-430x-large-lower-bad.d: New test.
	* testsuite/gas/msp430/attr-430x-large-lower-bad.l: New test.
	* testsuite/gas/msp430/attr-430x-large-lower-good.d: New test.
	* testsuite/gas/msp430/attr-430x-large-lower.s: New test.
	* testsuite/gas/msp430/msp430.exp: Run new tests.

include	* elf/msp430.h: Add enums for MSPABI and GNU object attribute tag names
	and values.

ld	* testsuite/ld-msp430-elf/attr-gnu-main.s: New test.
	* testsuite/ld-msp430-elf/attr-gnu-obj.s: New test.
	* testsuite/ld-msp430-elf/attr-gnu-region-lower-upper.d: New test.
	* testsuite/ld-msp430-elf/attr-gnu-region-lower.d: New test.
	* testsuite/ld-msp430-elf/attr-gnu-region-upper.d: New test.
	* testsuite/ld-msp430-elf/msp430-elf.exp: Run new tests.

2 files changed, 29 insertions, 0 deletions

diff --git a/gas/doc/as.texi b/gas/doc/as.texi
index b4598e8..93e80f9 100644
--- a/gas/doc/as.texi
+++ b/gas/doc/as.texi
@@ -7585,6 +7585,23 @@ The vector ABI used by this object file.  The value will be:
 @end itemize
 @end table
 
+@subsection MSP430 Attributes
+
+@table @r
+@item Tag_GNU_MSP430_Data_Region (4)
+The data region used by this object file.  The value will be:
+
+@itemize @bullet
+@item
+0 for files not using the large memory model.
+@item
+1 for files which have been compiled with the condition that all
+data is in the lower memory region, i.e. below address 0x10000.
+@item
+2 for files which allow data to be placed in the full 20-bit memory range.
+@end itemize
+@end table
+
 @node Defining New Object Attributes
 @section Defining New Object Attributes
 
diff --git a/gas/doc/c-msp430.texi b/gas/doc/c-msp430.texi
index 516c0038..3691f21 100644
--- a/gas/doc/c-msp430.texi
+++ b/gas/doc/c-msp430.texi
@@ -322,6 +322,18 @@ exist purely for pulling in object files from archives.  Note that
 this reloc is not sufficient to prevent garbage collection; use a
 KEEP() directive in the linker file to preserve such objects.
 
+@cindex @code{mspabi_attribute} directive, MSP430
+@item .mspabi_attribute
+This directive tells the assembler what the MSPABI build attributes for this
+file are.  This is used for validating the command line options passed to
+the assembler against the options the original source file was compiled with.
+The expected format is:
+@samp{.mspabi_attribute tag_name, tag_value}
+For example, to set the tag @code{OFBA_MSPABI_Tag_ISA} to @code{MSP430X}:
+@samp{.mspabi_attribute 4, 2}
+
+See the @cite{MSP430 EABI, document slaa534} for the details on tag names and
+values.
 @end table
 
 @node MSP430 Opcodes