Support ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX

Mark an ALLOC section, which should be placed in special memory area,
with SHF_GNU_MBIND.  Its sh_info field indicates the special memory
type.  GNU_MBIND section names start with ".mbind" so that they are
placed as orphan sections by linker.  All input GNU_MBIND sections
with the same sh_type, sh_flags and sh_info are placed in one output
GNU_MBIND section.  In executable and shared object, create a
GNU_MBIND segment for each GNU_MBIND section and its segment type is
PT_GNU_MBIND_LO plus the sh_info value.  Each GNU_MBIND segment is
aligned at page boundary.

The assembler syntax:

    .section .mbind.foo,"adx",%progbits
                          ^             0: Special memory type.
                          |
                         'd' for SHF_GNU_MBIND.

    .section .mbind.foo,"adx",%progbits,0x1
                          ^             1: Special memory type.
                          |
                         'd' for SHF_GNU_MBIND.

    .section .mbind.bar,"adG",%progbits,.foo_group,comdat,0x2
                          ^                               2: Special memory type.
                          |
                         'd' for SHF_GNU_MBIND.

bfd/

	* elf.c (get_program_header_size): Add a GNU_MBIND segment for
	each GNU_MBIND section and align GNU_MBIND section to page size.
	(_bfd_elf_map_sections_to_segments): Create a GNU_MBIND
	segment for each GNU_MBIND section.
	(_bfd_elf_init_private_section_data): Copy sh_info from input
	for GNU_MBIND section.

binutils/

	* NEWS: Mention support for ELF SHF_GNU_MBIND and
	PT_GNU_MBIND_XXX.
	* readelf.c (get_segment_type): Handle PT_GNU_MBIND_XXX.
	(get_elf_section_flags): Handle SHF_GNU_MBIND.
	(process_section_headers): Likewise.
	* testsuite/binutils-all/mbind1.s: New file.
	* testsuite/binutils-all/objcopy.exp: Run readelf test on
	mbind1.s.

gas/

	* NEWS: Mention support for ELF SHF_GNU_MBIND.
	* config/obj-elf.c (section_match): New.
	(get_section): Match both sh_info and group name.
	(obj_elf_change_section): Add argument for sh_info.  Pass both
	sh_info and group name to get_section. Issue an error for
	SHF_GNU_MBIND section without SHF_ALLOC.  Set sh_info.
	(obj_elf_parse_section_letters): Set SHF_GNU_MBIND for 'd'.
	(obj_elf_section): Support SHF_GNU_MBIND section info.
	* config/obj-elf.h (obj_elf_change_section): Add argument for
	sh_info.
	* config/tc-arm.c (start_unwind_section): Pass 0 as sh_info to
	obj_elf_change_section.
	* config/tc-ia64.c (obj_elf_vms_common): Likewise.
	* config/tc-microblaze.c (microblaze_s_data): Likewise.
	(microblaze_s_sdata): Likewise.
	(microblaze_s_rdata): Likewise.
	(microblaze_s_bss): Likewise.
	* config/tc-mips.c (s_change_section): Likewise.
	* config/tc-msp430.c (msp430_profiler): Likewise.
	* config/tc-rx.c (parse_rx_section): Likewise.
	* config/tc-tic6x.c (tic6x_start_unwind_section): Likewise.
	* doc/as.texinfo: Document 'd' for SHF_GNU_MBIND.
	* testsuite/gas/elf/elf.exp: Run section12a, section12b and
	section13.
	* testsuite/gas/elf/section10.d: Updated.
	* testsuite/gas/elf/section10.s: Likewise.
	* testsuite/gas/elf/section12.s: New file.
	* testsuite/gas/elf/section12a.d: Likewise.
	* testsuite/gas/elf/section12b.d: Likewise.
	* testsuite/gas/elf/section13.l: Likewise.
	* testsuite/gas/elf/section13.d: Likewise.
	* testsuite/gas/elf/section13.s: Likewise.

include/

	* elf/common.h (PT_GNU_MBIND_NUM): New.
	(PT_GNU_MBIND_LO): Likewise.
	(PT_GNU_MBIND_HI): Likewise.
	(SHF_GNU_MBIND): Likewise.

ld/

	* NEWS: Mention support for ELF SHF_GNU_MBIND and
	PT_GNU_MBIND_XXX.
	* emultempl/elf32.em (gld${EMULATION_NAME}_place_orphan): Place
	input GNU_MBIND sections with the same type, attributes and
	sh_info field into a single output GNU_MBIND section.
	* testsuite/ld-elf/elf.exp: Run mbind2a and mbind2b.
	* testsuite/ld-elf/mbind1.s: New file.
	* testsuite/ld-elf/mbind1a.d: Likewise.
	* testsuite/ld-elf/mbind1b.d: Likewise.
	* testsuite/ld-elf/mbind1c.d: Likewise.
	* testsuite/ld-elf/mbind2a.s: Likewise.
	* testsuite/ld-elf/mbind2b.c: Likewise.

5 files changed, 61 insertions, 3 deletions

diff --git a/binutils/ChangeLog b/binutils/ChangeLog
index 5d81b35..d347336 100644
--- a/binutils/ChangeLog
+++ b/binutils/ChangeLog
@@ -1,3 +1,14 @@
+2017-04-04  H.J. Lu  <hongjiu.lu@intel.com>
+
+	* NEWS: Mention support for ELF SHF_GNU_MBIND and
+	PT_GNU_MBIND_XXX.
+	* readelf.c (get_segment_type): Handle PT_GNU_MBIND_XXX.
+	(get_elf_section_flags): Handle SHF_GNU_MBIND.
+	(process_section_headers): Likewise.
+	* testsuite/binutils-all/mbind1.s: New file.
+	* testsuite/binutils-all/objcopy.exp: Run readelf test on
+	mbind1.s.
+
 2017-04-03  Nick Clifton  <nickc@redhat.com>
 
 	PR binutils/21345
diff --git a/binutils/NEWS b/binutils/NEWS
index d9d65c7..c03539d 100644
--- a/binutils/NEWS
+++ b/binutils/NEWS
@@ -1,5 +1,7 @@
 -*- text -*-
 
+* Add support for ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX.
+
 * Add support for the wasm32 ELF conversion of the WebAssembly file format.
 
 * Add --inlines option to objdump, which extends the --line-numbers option
diff --git a/binutils/readelf.c b/binutils/readelf.c
index b573921..d2b8dd4 100644
--- a/binutils/readelf.c
+++ b/binutils/readelf.c
@@ -3825,7 +3825,12 @@ get_segment_type (unsigned long p_type)
     case PT_GNU_RELRO:  return "GNU_RELRO";
 
     default:
-      if ((p_type >= PT_LOPROC) && (p_type <= PT_HIPROC))
+      if (p_type >= PT_GNU_MBIND_LO && p_type <= PT_GNU_MBIND_HI)
+	{
+	  sprintf (buff, "GNU_MBIND+%#lx",
+		   p_type - PT_GNU_MBIND_LO);
+	}
+      else if ((p_type >= PT_LOPROC) && (p_type <= PT_HIPROC))
 	{
 	  const char * result;
 
@@ -5544,7 +5549,9 @@ get_elf_section_flags (bfd_vma sh_flags)
       /* ARM specific.  */
       /* 21 */ { STRING_COMMA_LEN ("ENTRYSECT") },
       /* 22 */ { STRING_COMMA_LEN ("ARM_PURECODE") },
-      /* 23 */ { STRING_COMMA_LEN ("COMDEF") }
+      /* 23 */ { STRING_COMMA_LEN ("COMDEF") },
+      /* GNU specific.  */
+      /* 24 */ { STRING_COMMA_LEN ("GNU_MBIND") },
     };
 
   if (do_section_details)
@@ -5577,6 +5584,7 @@ get_elf_section_flags (bfd_vma sh_flags)
 	    case SHF_TLS:		sindex = 9; break;
 	    case SHF_EXCLUDE:		sindex = 18; break;
 	    case SHF_COMPRESSED:	sindex = 20; break;
+	    case SHF_GNU_MBIND:		sindex = 24; break;
 
 	    default:
 	      sindex = -1;
@@ -5670,6 +5678,7 @@ get_elf_section_flags (bfd_vma sh_flags)
 	    case SHF_TLS:		*p = 'T'; break;
 	    case SHF_EXCLUDE:		*p = 'E'; break;
 	    case SHF_COMPRESSED:	*p = 'C'; break;
+	    case SHF_GNU_MBIND:		*p = 'D'; break;
 
 	    default:
 	      if ((elf_header.e_machine == EM_X86_64
@@ -6198,7 +6207,9 @@ process_section_headers (FILE * file)
 	      if (section->sh_info < 1 || section->sh_info >= elf_header.e_shnum)
 		warn (_("[%2u]: Expected link to another section in info field"), i);
 	    }
-	  else if (section->sh_type < SHT_LOOS && section->sh_info != 0)
+	  else if (section->sh_type < SHT_LOOS
+		   && (section->sh_flags & SHF_GNU_MBIND) == 0
+		   && section->sh_info != 0)
 	    warn (_("[%2u]: Unexpected value (%u) in info field.\n"),
 		  i, section->sh_info);
 	  break;
diff --git a/binutils/testsuite/binutils-all/mbind1.s b/binutils/testsuite/binutils-all/mbind1.s
new file mode 100644
index 0000000..41faad4
--- /dev/null
+++ b/binutils/testsuite/binutils-all/mbind1.s
@@ -0,0 +1,33 @@
+	.section .mbind.data,"adw",%progbits
+	.byte 1
+
+	.section .mbind.data,"adw",%progbits,0x3
+	.byte 2
+
+	.section .mbind.text,"adx",%progbits
+	.byte 3
+
+	.section .mbind.text,"adx",%progbits,0x3
+	.byte 4
+
+	.section .mbind.bss,"adw",%nobits
+	.zero 5
+
+	.section .mbind.bss,"adw",%nobits,0x3
+	.zero 6
+
+	.section .mbind.rodata,"adG",%progbits,.foo_group,comdat,0x2
+	.byte 7
+
+	.section .mbind.data,"adGw",%progbits,.foo_group,comdat
+	.byte 8
+
+	.section .mbind.data,"adGw",%progbits,.foo_group,comdat,0x3
+	.byte 9
+
+	# Check that .pushsection works as well.
+	.pushsection .mbind.text,"adGx",%progbits,.foo_group,comdat,0x3
+	.byte 10
+
+	.popsection
+	.byte 11
diff --git a/binutils/testsuite/binutils-all/objcopy.exp b/binutils/testsuite/binutils-all/objcopy.exp
index 7ecc0d5..6d57837 100644
--- a/binutils/testsuite/binutils-all/objcopy.exp
+++ b/binutils/testsuite/binutils-all/objcopy.exp
@@ -1049,6 +1049,7 @@ if [is_elf_format] {
     objcopy_test_readelf "ELF group" group-2.s
     objcopy_test_readelf "ELF group" group-3.s
     objcopy_test_readelf "ELF group" group-4.s
+    objcopy_test_readelf "GNU_MBIND section" mbind1.s
     run_dump_test "group-5"
     run_dump_test "group-6"
     run_dump_test "copy-1"