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, 46 insertions, 0 deletions

diff --git a/include/ChangeLog b/include/ChangeLog
index c409344df00..13b15f00a71 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,8 @@
+2019-10-07  Jozef Lawrynowicz  <jozef.l@mittosystems.com>
+
+	* elf/msp430.h: Add enums for MSPABI and GNU object attribute tag
+	names and values.
+
 2019-09-23  Nick Alcock  <nick.alcock@oracle.com>
 
 	* ctf-api.h (ctf_cuname_set): Can now fail, returning int.
diff --git a/include/elf/msp430.h b/include/elf/msp430.h
index e060804b665..ce2cf5b3c7d 100644
--- a/include/elf/msp430.h
+++ b/include/elf/msp430.h
@@ -58,6 +58,47 @@
 #define OFBA_MSPABI_Tag_ISA		4
 #define OFBA_MSPABI_Tag_Code_Model	6
 #define OFBA_MSPABI_Tag_Data_Model	8
+#define OFBA_MSPABI_Tag_enum_size	10	/* Unused by GNU.  */
+
+/* GNU Object attribute tags.  */
+enum
+{
+  /* 0-3 are generic.  */
+
+  /* Define a GNU attribute for keeping track of whether the compiler has
+     generated code assuming that the upper region could be in use.
+     Added by the assembler based on the -mdata-region option.
+     This tag is ignored unless the large memory model is in use.  */
+  Tag_GNU_MSP430_Data_Region = 4,
+};
+
+/* Object attribute values.  */
+enum
+{
+  /* Values defined for OFBA_MSPABI_Tag_ISA.  */
+  OFBA_MSPABI_Val_ISA_NONE = 0,
+  OFBA_MSPABI_Val_ISA_MSP430 = 1,
+  OFBA_MSPABI_Val_ISA_MSP430X = 2,
+
+  /* Values defined for OFBA_MSPABI_Tag_Code_Model.  */
+  OFBA_MSPABI_Val_Code_Model_NONE = 0,
+  OFBA_MSPABI_Val_Code_Model_SMALL = 1,
+  OFBA_MSPABI_Val_Code_Model_LARGE = 2,
+
+  /* Values defined for OFBA_MSPABI_Tag_Data_Model.  */
+  OFBA_MSPABI_Val_Data_Model_NONE = 0,
+  OFBA_MSPABI_Val_Data_Model_SMALL = 1,
+  OFBA_MSPABI_Val_Data_Model_LARGE = 2,
+  OFBA_MSPABI_Val_Data_Model_RESTRICTED = 3,	/* Unused by GNU.  */
+
+  /* Values defined for Tag_GNU_MSP430_Data_Region.  */
+  Val_GNU_MSP430_Data_Region_NONE = 0,
+  /* The default data region.  Assumes all data is below address 0x10000.  */
+  Val_GNU_MSP430_Data_Region_Lower = 1,
+  /* Set if -mdata-region={none,upper,either}.  Assumes
+     data could be placed at or above address 0x10000.  */
+  Val_GNU_MSP430_Data_Region_Any = 2,
+};
 
 /* Relocations.  */
 START_RELOC_NUMBERS (elf_msp430_reloc_type)