Improve MSP430 section placement.

ld	* emultempl/msp430.em (change_output_section): New function.
	(move_prefixed_section): New function.
	(add_region_prefix): New function.
	(msp430_elf_after_open): New function.
	(gld${EMULATION_NAME}_add_options): Implement.
	(gld${EMULATION_NAME}_list_options): Implement.
	(gld${EMULATION_NAME}_handle_option): Implement.
	* ld.texinfo: Document new options.
	* testsuite/ld-msp430-elf/main-bss-lower.d: New.
	* testsuite/ld-msp430-elf/main-bss-upper.d: New.
	* testsuite/ld-msp430-elf/main-const-lower.d: New.
	* testsuite/ld-msp430-elf/main-const-upper.d: New.
	* testsuite/ld-msp430-elf/main-text-lower.d: New.
	* testsuite/ld-msp430-elf/main-text-upper.d: New.
	* testsuite/ld-msp430-elf/main-var-lower.d: New.
	* testsuite/ld-msp430-elf/main-var-upper.d: New.
	* testsuite/ld-msp430-elf/main-with-data-bss-unique-sec.s: New.
	* testsuite/ld-msp430-elf/main-with-data-bss.s: New.
	* testsuite/ld-msp430-elf/main-with-text-rodata-unique-sec.s: New.
	* testsuite/ld-msp430-elf/main-with-text-rodata.s: New.
	* testsuite/ld-msp430-elf/msp430-elf.exp: New.
	* testsuite/ld-msp430-elf/msp430-no-lower.ld: New.
	* testsuite/ld-msp430-elf/msp430.ld: New.
	* emultempl/msp430.em (data_statement_size): New.
	(eval_upper_either_sections): New.
	(eval_lower_either_sections): New.
	(intermediate_relax_sections): New.
	(msp430_elf_after_allocation): New.
	* emultempl/msp430.em (gld${EMULATION_NAME}_place_orphan): Always
	place sections in the lower region.

gas	* config/tc-msp430.c (md_parse_option): Define high data and high
	bss symbols if -mdata-region is passed.
	Define -mdata-region open.
	* doc/c-msp430.texi: Document -mdata-region.
	* testsuite/gas/msp430/high-data-bss-sym.d: New test.
	* testsuite/gas/msp430/high-data-bss-sym.s: New.
	* testsuite/gas/msp430/msp430.exp: Add -mdata-region tests.

6 files changed, 70 insertions, 3 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 8bea1df..3e250d3 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,13 @@
+2017-08-29  Jozef Lawrynowicz  <jozef.l@somniumtech.com>
+
+	* config/tc-msp430.c (md_parse_option): Define high data and high
+	bss symbols if -mdata-region is passed.
+	Define -mdata-region open.
+	* doc/c-msp430.texi: Document -mdata-region.
+	* testsuite/gas/msp430/high-data-bss-sym.d: New test.
+	* testsuite/gas/msp430/high-data-bss-sym.s: New.
+	* testsuite/gas/msp430/msp430.exp: Add -mdata-region tests.
+
 2017-08-23  Alexander Fedotov <alexander.fedotov@nxp.com>
 	    Edmar Wienskoski <edmar.wienskoski@nxp.com
 
diff --git a/gas/config/tc-msp430.c b/gas/config/tc-msp430.c
index 91e0a73..62a34ed 100644
--- a/gas/config/tc-msp430.c
+++ b/gas/config/tc-msp430.c
@@ -676,6 +676,8 @@ static bfd_boolean warn_interrupt_nops = TRUE;
 #define OPTION_MCPU 'c'
 #define OPTION_MOVE_DATA 'd'
 static bfd_boolean move_data = FALSE;
+#define OPTION_DATA_REGION 'r'
+static bfd_boolean upper_data_region_in_use = FALSE;
 
 enum
 {
@@ -1448,6 +1450,12 @@ md_parse_option (int c, const char * arg)
     case OPTION_MOVE_DATA:
       move_data = TRUE;
       return 1;
+
+    case OPTION_DATA_REGION:
+      if (strcmp (arg, "upper") == 0
+	  || strcmp (arg, "either") == 0)
+	upper_data_region_in_use = TRUE;
+      return 1;
     }
 
   return 0;
@@ -1478,14 +1486,19 @@ msp430_make_init_symbols (const char * name)
 
   /* Note - data assigned to the .either.data section may end up being
      placed in the .upper.data section if the .lower.data section is
-     full.  Hence the need to define the crt0 symbol.  */
+     full.  Hence the need to define the crt0 symbol.
+     The linker may create upper or either data sections, even when none exist
+     at the moment, so use the value of the data-region flag to determine if
+     the symbol is needed.  */
   if (strncmp (name, ".either.data", 12) == 0
-      || strncmp (name, ".upper.data", 11) == 0)
+      || strncmp (name, ".upper.data", 11) == 0
+      || upper_data_region_in_use)
     (void) symbol_find_or_make ("__crt0_move_highdata");
 
   /* See note about .either.data above.  */
   if (strncmp (name, ".upper.bss", 10) == 0
-      || strncmp (name, ".either.bss", 11) == 0)
+      || strncmp (name, ".either.bss", 11) == 0
+      || upper_data_region_in_use)
     (void) symbol_find_or_make ("__crt0_init_highbss");
 }
 
@@ -1570,6 +1583,7 @@ struct option md_longopts[] =
   {"mY", no_argument, NULL, OPTION_NO_WARN_INTR_NOPS},
   {"my", no_argument, NULL, OPTION_WARN_INTR_NOPS},
   {"md", no_argument, NULL, OPTION_MOVE_DATA},
+  {"mdata-region", required_argument, NULL, OPTION_DATA_REGION},
   {NULL, no_argument, NULL, 0}
 };
 
@@ -1601,6 +1615,9 @@ md_show_usage (FILE * stream)
 	   _("  -my - warn about missing NOPs after changing interrupts (default)\n"));
   fprintf (stream,
 	   _("  -md - Force copying of data from ROM to RAM at startup\n"));
+  fprintf (stream,
+	   _("  -mdata-region={none|lower|upper|either} - select region data will be\n"
+	     "    placed in.\n"));
 }
 
 symbolS *
diff --git a/gas/doc/c-msp430.texi b/gas/doc/c-msp430.texi
index eb0e757..d80f540 100644
--- a/gas/doc/c-msp430.texi
+++ b/gas/doc/c-msp430.texi
@@ -107,6 +107,19 @@ disables warnings about missing NOP instructions.
 mark the object file as one that requires data to copied from ROM to
 RAM at execution startup.  Disabled by default.
 
+@item -mdata-region=@var{region}
+Select the region data will be placed in.
+Region placement is performed by the compiler and linker.  The only effect this
+option will have on the assembler is that if @var{upper} or @var{either} is
+selected, then the symbols to initialise high data and bss will be defined.
+Valid @var{region} values are:
+@table @code
+@item none
+@item lower
+@item upper
+@item either
+@end table
+
 @end table
 
 @node MSP430 Syntax
diff --git a/gas/testsuite/gas/msp430/high-data-bss-sym.d b/gas/testsuite/gas/msp430/high-data-bss-sym.d
new file mode 100644
index 0000000..1c8d95b
--- /dev/null
+++ b/gas/testsuite/gas/msp430/high-data-bss-sym.d
@@ -0,0 +1,6 @@
+#objdump: -t
+#name: Check symbols to initialise high data and high bss have been defined
+#...
+.*__crt0_move_highdata.*
+.*__crt0_init_highbss.*
+#pass
diff --git a/gas/testsuite/gas/msp430/high-data-bss-sym.s b/gas/testsuite/gas/msp430/high-data-bss-sym.s
new file mode 100644
index 0000000..1e6bf72
--- /dev/null
+++ b/gas/testsuite/gas/msp430/high-data-bss-sym.s
@@ -0,0 +1,19 @@
+	.file	"main.c"
+.text
+	.balign 2
+	.global	main
+	.type	main, @function
+main:
+; start of function
+; framesize_regs:     0
+; framesize_locals:   0
+; framesize_outgoing: 0
+; framesize:          0
+; elim ap -> fp       2
+; elim fp -> sp       0
+; saved regs:(none)
+	; start of prologue
+	; end of prologue
+.L2:
+	BR	#.L2
+	.size	main, .-main
diff --git a/gas/testsuite/gas/msp430/msp430.exp b/gas/testsuite/gas/msp430/msp430.exp
index b83e1ac..0dfb271 100644
--- a/gas/testsuite/gas/msp430/msp430.exp
+++ b/gas/testsuite/gas/msp430/msp430.exp
@@ -24,4 +24,6 @@ if [expr [istarget "msp430-*-*"]]  then {
     run_dump_test "bad"
     run_dump_test "errata_warns"
     run_dump_test "errata_fixes"
+    run_dump_test "high-data-bss-sym" { { as "-mdata-region=upper" } }
+    run_dump_test "high-data-bss-sym" { { as "-mdata-region=either" } }
 }