Add support for ARM's NOREAD section flag.

include/elf
     * arm.h: Add arm SHF_ARM_NOREAD section flag.

bfd  * bfd-in2.h: Regenerate.
     * section.c: Add SEC_ELF_NOREAD.
     * elf32-arm.c (elf32_arm_post_process_headers): Only set
     PF_X attribute if a segment only contains section with
     SHF_ARM_NOREAD flag.
     (elf32_arm_fake_sections): Add SEC_ELF_NOREAD conversion.
     (elf32_arm_section_flags): New function to convert SHF_ARM_NOREAD
     to bfd flag.
     (elf32_arm_lookup_section_flags): New function to allow
     INPUT_SECTION_FLAGS directive with SHF_ARM_NOREAD flag.
     (elf32_arm_special_sections): Add special sections array
     to catch section prefix by '.text.noread' pattern.

ld/testsuite
     * ld-arm/arm-elf.exp: New tests.
     * ld-arm/thumb1-input-section-flag-match.d: New
     * ld-arm/thumb1-input-section-flag-match.s: New
     * ld-arm/thumb1-noread-not-present-mixing-two-section.d: New
     * ld-arm/thumb1-noread-not-present-mixing-two-section.s: New
     * ld-arm/thumb1-noread-present-one-section.d: New
     * ld-arm/thumb1-noread-present-one-section.s: New
     * ld-arm/thumb1-noread-present-two-section.d: New
     * ld-arm/thumb1-noread-present-two-section.s: New

binutils
	* readelf.c (get_elf_section_flags): Add support for ARM specific
	section flags.

4 files changed, 80 insertions, 0 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index f81e90d..03fbb34 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,18 @@
+2015-12-22 Mickael Guene <mickael.guene@st.com>
+
+	* bfd-in2.h: Regenerate.
+	* section.c: Add SEC_ELF_NOREAD.
+	* elf32-arm.c (elf32_arm_post_process_headers): Only set
+	PF_X attribute if a segment only contains section with
+	SHF_ARM_NOREAD flag.
+	(elf32_arm_fake_sections): Add SEC_ELF_NOREAD conversion.
+	(elf32_arm_section_flags): New function to convert SHF_ARM_NOREAD
+	to bfd flag.
+	(elf32_arm_lookup_section_flags): New function to allow
+	INPUT_SECTION_FLAGS directive with SHF_ARM_NOREAD flag.
+	(elf32_arm_special_sections): Add special sections array
+	to catch section prefix by '.text.noread' pattern.
+
 2015-12-18  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* coff-x86_64.c (coff_amd64_reloc): Fix formatting.
diff --git a/bfd/bfd-in2.h b/bfd/bfd-in2.h
index 39eb19a..ca0cafd 100644
--- a/bfd/bfd-in2.h
+++ b/bfd/bfd-in2.h
@@ -1432,6 +1432,9 @@ typedef struct bfd_section
      when memory read flag isn't set. */
 #define SEC_COFF_NOREAD 0x40000000
 
+  /* Indicate that section has the no read flag set.  */
+#define SEC_ELF_NOREAD 0x80000000
+
   /*  End of section flags.  */
 
   /* Some internal packed boolean fields.  */
diff --git a/bfd/elf32-arm.c b/bfd/elf32-arm.c
index 49d6469..5d31ef2 100644
--- a/bfd/elf32-arm.c
+++ b/bfd/elf32-arm.c
@@ -15417,6 +15417,7 @@ elf32_arm_post_process_headers (bfd * abfd, struct bfd_link_info * link_info ATT
 {
   Elf_Internal_Ehdr * i_ehdrp;	/* ELF file header, internal form.  */
   struct elf32_arm_link_hash_table *globals;
+  struct elf_segment_map *m;
 
   i_ehdrp = elf_elfheader (abfd);
 
@@ -15442,6 +15443,26 @@ elf32_arm_post_process_headers (bfd * abfd, struct bfd_link_info * link_info ATT
       else
 	i_ehdrp->e_flags |= EF_ARM_ABI_FLOAT_SOFT;
     }
+
+  /* Scan segment to set p_flags attribute if it contains only sections with
+     SHF_ARM_NOREAD flag.  */
+  for (m = elf_seg_map (abfd); m != NULL; m = m->next)
+    {
+      unsigned int j;
+
+      if (m->count == 0)
+	continue;
+      for (j = 0; j < m->count; j++)
+	{
+	  if (!(elf_section_flags (m->sections[j]) & SHF_ARM_NOREAD))
+	    break;
+	}
+      if (j == m->count)
+	{
+	  m->p_flags = PF_X;
+	  m->p_flags_valid = 1;
+	}
+    }
 }
 
 static enum elf_reloc_type_class
@@ -15493,6 +15514,10 @@ elf32_arm_fake_sections (bfd * abfd, Elf_Internal_Shdr * hdr, asection * sec)
       hdr->sh_type = SHT_ARM_EXIDX;
       hdr->sh_flags |= SHF_LINK_ORDER;
     }
+
+  if (sec->flags & SEC_ELF_NOREAD)
+    hdr->sh_flags |= SHF_ARM_NOREAD;
+
   return TRUE;
 }
 
@@ -17690,6 +17715,33 @@ elf32_arm_get_synthetic_symtab (bfd *abfd,
   return n;
 }
 
+static const struct bfd_elf_special_section
+elf32_arm_special_sections[] =
+{
+/* Catch sections with .text.noread prefix and apply allocate, execute and
+   noread section attributes.  */
+  { STRING_COMMA_LEN (".text.noread"),  -2, SHT_PROGBITS,
+    SHF_ALLOC + SHF_EXECINSTR + SHF_ARM_NOREAD },
+  { NULL,			      0, 0, 0,			0 }
+};
+
+static bfd_boolean
+elf32_arm_section_flags (flagword *flags, const Elf_Internal_Shdr * hdr)
+{
+  if (hdr->sh_flags & SHF_ARM_NOREAD)
+    *flags |= SEC_ELF_NOREAD;
+  return TRUE;
+}
+
+static flagword
+elf32_arm_lookup_section_flags (char *flag_name)
+{
+  if (!strcmp (flag_name, "SHF_ARM_NOREAD"))
+    return SHF_ARM_NOREAD;
+
+  return SEC_NO_FLAGS;
+}
+
 #define ELF_ARCH			bfd_arch_arm
 #define ELF_TARGET_ID			ARM_ELF_DATA
 #define ELF_MACHINE_CODE		EM_ARM
@@ -17768,6 +17820,13 @@ elf32_arm_get_synthetic_symtab (bfd *abfd,
 #define elf_backend_obj_attrs_order		elf32_arm_obj_attrs_order
 #define elf_backend_obj_attrs_handle_unknown 	elf32_arm_obj_attrs_handle_unknown
 
+#undef  elf_backend_special_sections
+#define elf_backend_special_sections 		elf32_arm_special_sections
+#undef elf_backend_section_flags
+#define elf_backend_section_flags		elf32_arm_section_flags
+#undef elf_backend_lookup_section_flags_hook
+#define elf_backend_lookup_section_flags_hook   elf32_arm_lookup_section_flags
+
 #include "elf32-target.h"
 
 /* Native Client targets.  */
diff --git a/bfd/section.c b/bfd/section.c
index 247d98a..1a78c11 100644
--- a/bfd/section.c
+++ b/bfd/section.c
@@ -361,6 +361,9 @@ CODE_FRAGMENT
 .     when memory read flag isn't set. *}
 .#define SEC_COFF_NOREAD 0x40000000
 .
+.  {* Indicate that section has the no read flag set.  *}
+.#define SEC_ELF_NOREAD 0x80000000
+.
 .  {*  End of section flags.  *}
 .
 .  {* Some internal packed boolean fields.  *}