[binutils-gdb/binutils-2_36-branch] Backport patch to fix a quadratic slow down in the BFD library.

[Nick Clifton]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=84fd26d8209e99fc3a432dd0b09b6c053de1ce65

commit 84fd26d8209e99fc3a432dd0b09b6c053de1ce65
Author: Nick Clifton <nickc@redhat.com>
Date:   Fri Jul 9 16:54:59 2021 +0100

    Backport patch to fix a quadratic slow down in the BFD library.
    
            PR 28058
    bfd     * elf.c (bfd_section_from_shdr): Set has_secondary_relocs flag.
            (_bfd_elf_slurp_secondary_reloc_section): Use it for early-out.

Diff:
---
 bfd/ChangeLog | 10 ++++++++++
 bfd/elf.c     |  5 +++++
 2 files changed, 15 insertions(+)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index cd6f3706fe2..0b035fbc3ae 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,13 @@
+2021-07-09  Nick Clifton  <nickc@redhat.com>
+
+	Backport from mainline:
+
+	2021-06-08  Michael Matz  <matz@suse.de>
+
+	PR 28058
+	* elf.c (bfd_section_from_shdr): Set has_secondary_relocs flag.
+	(_bfd_elf_slurp_secondary_reloc_section): Use it for early-out.
+
 2021-07-09  Nick Clifton  <nickc@redhat.com>
 
 	Backport this patch from the mainline:
diff --git a/bfd/elf.c b/bfd/elf.c
index 36733e080dd..af62aadc3d4 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -2454,6 +2454,8 @@ bfd_section_from_shdr (bfd *abfd, unsigned int shindex)
 		     "for section %pA found - ignoring"),
 		   abfd, name, target_sect);
 	      }
+	    else
+	      esdt->has_secondary_relocs = TRUE;
 	    goto success;
 	  }
 
@@ -12587,6 +12589,9 @@ _bfd_elf_slurp_secondary_reloc_section (bfd *       abfd,
 #endif
     r_sym = elf32_r_sym;
   
+  if (!elf_section_data (sec)->has_secondary_relocs)
+    return TRUE;
+
   /* Discover if there are any secondary reloc sections
      associated with SEC.  */
   for (relsec = abfd->sections; relsec != NULL; relsec = relsec->next)