code.ossystems Code Review - openembedded-core.git/blob

   1 From 9619a608528383a44ccc1637ae939b5f3e97adc5 Mon Sep 17 00:00:00 2001
   2 From: Sandra Loosemore <sandra@codesourcery.com>
   3 Date: Wed, 9 Dec 2015 16:13:58 -0800
   4 Subject: [PATCH 13/14] Fix GOT address computations in initial PLT entries for
   5  nios2.
   6
   7 2015-12-09  Sandra Loosemore  <sandra@codesourcery.com>
   8
   9         bfd/
  10         * elf32-nios2.c (nios2_elf32_finish_dynamic_sections): Correct
  11         %hiadj/%lo computations for _GLOBAL_OFFSET_TABLE_ in initial
  12         PLT entries.  Assert alignment requirements.
  13
  14 Signed-off-by: Marek Vasut <marex@denx.de>
  15 Upstream-Status: Backport
  16 ---
  17  bfd/elf32-nios2.c | 23 ++++++++++++++++-------
  18  1 file changed, 16 insertions(+), 7 deletions(-)
  19
  20 diff --git a/bfd/elf32-nios2.c b/bfd/elf32-nios2.c
  21 index 6b29d8b..1c54320 100644
  22 --- a/bfd/elf32-nios2.c
  23 +++ b/bfd/elf32-nios2.c
  24 @@ -5383,12 +5383,17 @@ nios2_elf32_finish_dynamic_sections (bfd *output_bfd,
  25                                  + sgotplt->output_offset);
  26           if (bfd_link_pic (info))
  27             {
  28 -             bfd_vma corrected = got_address - (splt->output_section->vma
  29 -                                                + splt->output_offset + 4);
  30 +             bfd_vma got_pcrel = got_address - (splt->output_section->vma
  31 +                                                + splt->output_offset);
  32 +             /* Both GOT and PLT must be aligned to a 16-byte boundary
  33 +                for the two loads to share the %hiadj part.  The 4-byte
  34 +                offset for nextpc is accounted for in the %lo offsets
  35 +                on the loads.  */
  36 +             BFD_ASSERT ((got_pcrel & 0xf) == 0);
  37               nios2_elf32_install_data (splt, nios2_so_plt0_entry, 0, 6);
  38 -             nios2_elf32_install_imm16 (splt, 4, hiadj (corrected));
  39 -             nios2_elf32_install_imm16 (splt, 12, (corrected & 0xffff) + 4);
  40 -             nios2_elf32_install_imm16 (splt, 16, (corrected & 0xffff) + 8);
  41 +             nios2_elf32_install_imm16 (splt, 4, hiadj (got_pcrel));
  42 +             nios2_elf32_install_imm16 (splt, 12, got_pcrel & 0xffff);
  43 +             nios2_elf32_install_imm16 (splt, 16, (got_pcrel + 4) & 0xffff);
  44             }
  45           else
  46             {
  47 @@ -5404,6 +5409,10 @@ nios2_elf32_finish_dynamic_sections (bfd *output_bfd,
  48                             6 | ((res_size - (res_offset + 4)) << 6),
  49                             splt->contents + res_offset);
  50
  51 +             /* The GOT must be aligned to a 16-byte boundary for the
  52 +                two loads to share the same %hiadj part.  */
  53 +             BFD_ASSERT ((got_address & 0xf) == 0);
  54 +
  55               nios2_elf32_install_data (splt, nios2_plt0_entry, res_size, 7);
  56               nios2_elf32_install_imm16 (splt, res_size, hiadj (res_start));
  57               nios2_elf32_install_imm16 (splt, res_size + 4,
  58 @@ -5411,9 +5420,9 @@ nios2_elf32_finish_dynamic_sections (bfd *output_bfd,
  59               nios2_elf32_install_imm16 (splt, res_size + 12,
  60                                          hiadj (got_address));
  61               nios2_elf32_install_imm16 (splt, res_size + 16,
  62 -                                        (got_address & 0xffff) + 4);
  63 +                                        (got_address + 4) & 0xffff);
  64               nios2_elf32_install_imm16 (splt, res_size + 20,
  65 -                                        (got_address & 0xffff) + 8);
  66 +                                        (got_address + 8) & 0xffff);
  67             }
  68         }
  69      }
  70 --
  71 2.7.1
  72