ELF: Support .noinit and .persistent sections

The ".persistent" section is for data that should be initialized during
load, but not during application reset.

The ".noinit" section is for data that should not be initialized during
load or application reset.

Targets utilizing the elf.sc linker script template can define
HAVE_{NOINIT,PERSISTENT}=yes to include the .noinit or .persistent
output sections in the generated linker script.

Targets with existing support for .noinit did not handle unique
.noinit.* and .gnu.linkonce.n.* sections the .noinit output section,
this patch also fixes that.

bfd/ChangeLog:

	* elf.c (special_sections_g): Add .gnu.linkonce.n and .gnu.linkonce.p.
	(special_sections_n): Add .noinit.
	(special_sections_p): Add .persistent.

binutils/ChangeLog:

	* testsuite/lib/binutils-common.exp (supports_noinit_section): New.
	(supports_persistent_section): New.

gas/ChangeLog:

	* testsuite/gas/elf/elf.exp: Run new tests.
	* testsuite/gas/elf/section25.d: New test.
	* testsuite/gas/elf/section25.s: New test.
	* testsuite/gas/elf/section26.d: New test.
	* testsuite/gas/elf/section26.s: New test.

ld/ChangeLog:

	* emulparams/armelf.sh (OTHER_SECTIONS): Remove .noinit section
	definition.
	Define HAVE_{NOINIT,PERSISTENT}=yes.
	* scripttempl/avr.sc (.noinit): Add .noinit.* and .gnu.linkonce.n.*
	input section wildcard patterns.
	* scripttempl/elf.sc: Define .noinit and .persistent sections when
	HAVE_NOINIT or HAVE_PERSISTENT are defined to "yes".
	* scripttempl/elf32msp430.sc (.noinit): Add .noinit.* and
	.gnu.linkonce.n.*. input section wildcard patterns.
	(.persistent): Add .persistent.* and
	.gnu.linkonce.p.*. input section wildcard patterns.
	* scripttempl/elfarcv2.sc (.noinit): Add .noinit.* and
	.gnu.linkonce.n.*. input section wildcard patterns.
	* scripttempl/pru.sc: Likewise.
	* testsuite/ld-elf/noinit-sections-1.d: New test.
	* testsuite/ld-elf/noinit-sections-2.d: New test.
	* testsuite/ld-elf/noinit-sections-2.l: New test.
	* testsuite/ld-elf/noinit-sections.s: New test.
	* testsuite/ld-elf/persistent-sections-1.d: New test.
	* testsuite/ld-elf/persistent-sections-2.d: New test.
	* testsuite/ld-elf/persistent-sections-2.l: New test.
	* testsuite/ld-elf/persistent-sections.s: New test.

1 files changed, 39 insertions, 0 deletions

diff --git a/binutils/testsuite/lib/binutils-common.exp b/binutils/testsuite/lib/binutils-common.exp
index a43639b..e83d121 100644
--- a/binutils/testsuite/lib/binutils-common.exp
+++ b/binutils/testsuite/lib/binutils-common.exp
@@ -345,6 +345,45 @@ proc check_relro_support { } {
     return $relro_available_saved
 }
 
+# Check for support of the .noinit section, used for data that is not
+# initialized at load, or during the application's initialization sequence.
+proc supports_noinit_section {} {
+    # .noinit is only supported by ELF targets.
+    if { ![is_elf_format] } {
+	return 0;
+    }
+
+    # Targets that set HAVE_NOINIT=yes in their emulparams script utilizing
+    # elf.sc, or explicitly define a .noinit section in their linker script.
+    #
+    # arc-*-* is not included here, since it only supports .noinit with the
+    # non-default arcv2elf emulation.
+    if {[istarget "arm-*-*"]
+	  || [istarget "avr-*-*"]
+	  || [istarget "msp430-*-*"]
+	  || [istarget "pru-*-*"] } {
+	return 1;
+    }
+    return 0;
+}
+
+# Check for support of the .persistent section, used for data that is
+# initialized at load, but not during the application's initialization sequence.
+proc supports_persistent_section {} {
+    # .persistent is only supported by ELF targets.
+    if { ![is_elf_format] } {
+	return 0;
+    }
+
+    # Targets that set HAVE_PERSISTENT=yes in their emulparams script utilizing
+    # elf.sc, or explicitly define a .persistent section in their linker script.
+    if { [istarget "arm-*-*"]
+	  || [istarget "msp430-*-*"] } {
+	return 1;
+    }
+    return 0;
+}
+
 # Compare two files line-by-line.  FILE_1 is the actual output and FILE_2
 # is the expected output.  Ignore blank lines in either file.
 #