| From 6a17eba5358549d0d6d195bb22b34cdbc068def2 Mon Sep 17 00:00:00 2001 |
| From: Volodymyr Arbatov <arbatov@cadence.com> |
| Date: Mon, 6 May 2013 09:43:21 -0800 |
| Subject: [PATCH] Use signed data type for R_XTENSA_DIFF* relocation offsets. |
| |
| R_XTENSA_DIFF relocation offsets are in fact signed. Treat them as such. |
| Add testcase that examines ld behaviour on R_XTENSA_DIFF relocation |
| changing sign during relaxation. |
| |
| 2014-05-02 Volodymyr Arbatov <arbatov@cadence.com> |
| David Weatherford <weath@cadence.com> |
| Max Filippov <jcmvbkbc@gmail.com> |
| |
| bfd/ |
| * elf32-xtensa.c (relax_section): treat R_XTENSA_DIFF* relocations as |
| signed. |
| |
| gas/ |
| * config/tc-xtensa.c (md_apply_fix): mark BFD_RELOC_XTENSA_DIFF* |
| fixups as signed. |
| --- |
| Backported from: 1058c7532d0b012ac329219264ddad59049fb6e6 |
| Changes to Changelog files and tests are dropped. |
| |
| bfd/elf32-xtensa.c | 32 ++++++++++++----------- |
| gas/config/tc-xtensa.c | 3 +++ |
| 2 files changed, 20 insertions(+), 15 deletions(-) |
| |
| diff --git a/bfd/elf32-xtensa.c b/bfd/elf32-xtensa.c |
| index edb04b4..8818d67 100644 |
| --- a/bfd/elf32-xtensa.c |
| +++ b/bfd/elf32-xtensa.c |
| @@ -222,11 +222,11 @@ static reloc_howto_type elf_howto_table[] = |
| FALSE, 0, 0, FALSE), |
| |
| /* Relocations for supporting difference of symbols. */ |
| - HOWTO (R_XTENSA_DIFF8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield, |
| + HOWTO (R_XTENSA_DIFF8, 0, 0, 8, FALSE, 0, complain_overflow_signed, |
| bfd_elf_xtensa_reloc, "R_XTENSA_DIFF8", FALSE, 0, 0xff, FALSE), |
| - HOWTO (R_XTENSA_DIFF16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield, |
| + HOWTO (R_XTENSA_DIFF16, 0, 1, 16, FALSE, 0, complain_overflow_signed, |
| bfd_elf_xtensa_reloc, "R_XTENSA_DIFF16", FALSE, 0, 0xffff, FALSE), |
| - HOWTO (R_XTENSA_DIFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield, |
| + HOWTO (R_XTENSA_DIFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed, |
| bfd_elf_xtensa_reloc, "R_XTENSA_DIFF32", FALSE, 0, 0xffffffff, FALSE), |
| |
| /* General immediate operand relocations. */ |
| @@ -9013,7 +9013,8 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info) |
| || r_type == R_XTENSA_DIFF16 |
| || r_type == R_XTENSA_DIFF32) |
| { |
| - bfd_vma diff_value = 0, new_end_offset, diff_mask = 0; |
| + bfd_signed_vma diff_value = 0; |
| + bfd_vma new_end_offset, diff_mask = 0; |
| |
| if (bfd_get_section_limit (abfd, sec) < old_source_offset) |
| { |
| @@ -9027,15 +9028,15 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info) |
| { |
| case R_XTENSA_DIFF8: |
| diff_value = |
| - bfd_get_8 (abfd, &contents[old_source_offset]); |
| + bfd_get_signed_8 (abfd, &contents[old_source_offset]); |
| break; |
| case R_XTENSA_DIFF16: |
| diff_value = |
| - bfd_get_16 (abfd, &contents[old_source_offset]); |
| + bfd_get_signed_16 (abfd, &contents[old_source_offset]); |
| break; |
| case R_XTENSA_DIFF32: |
| diff_value = |
| - bfd_get_32 (abfd, &contents[old_source_offset]); |
| + bfd_get_signed_32 (abfd, &contents[old_source_offset]); |
| break; |
| } |
| |
| @@ -9047,24 +9048,25 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info) |
| switch (r_type) |
| { |
| case R_XTENSA_DIFF8: |
| - diff_mask = 0xff; |
| - bfd_put_8 (abfd, diff_value, |
| + diff_mask = 0x7f; |
| + bfd_put_signed_8 (abfd, diff_value, |
| &contents[old_source_offset]); |
| break; |
| case R_XTENSA_DIFF16: |
| - diff_mask = 0xffff; |
| - bfd_put_16 (abfd, diff_value, |
| + diff_mask = 0x7fff; |
| + bfd_put_signed_16 (abfd, diff_value, |
| &contents[old_source_offset]); |
| break; |
| case R_XTENSA_DIFF32: |
| - diff_mask = 0xffffffff; |
| - bfd_put_32 (abfd, diff_value, |
| + diff_mask = 0x7fffffff; |
| + bfd_put_signed_32 (abfd, diff_value, |
| &contents[old_source_offset]); |
| break; |
| } |
| |
| - /* Check for overflow. */ |
| - if ((diff_value & ~diff_mask) != 0) |
| + /* Check for overflow. Sign bits must be all zeroes or all ones */ |
| + if ((diff_value & ~diff_mask) != 0 && |
| + (diff_value & ~diff_mask) != (-1 & ~diff_mask)) |
| { |
| (*link_info->callbacks->reloc_dangerous) |
| (link_info, _("overflow after relaxation"), |
| diff --git a/gas/config/tc-xtensa.c b/gas/config/tc-xtensa.c |
| index 58ace38..7547c0a0 100644 |
| --- a/gas/config/tc-xtensa.c |
| +++ b/gas/config/tc-xtensa.c |
| @@ -5867,12 +5867,15 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg) |
| { |
| case BFD_RELOC_8: |
| fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF8; |
| + fixP->fx_signed = 1; |
| break; |
| case BFD_RELOC_16: |
| fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF16; |
| + fixP->fx_signed = 1; |
| break; |
| case BFD_RELOC_32: |
| fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF32; |
| + fixP->fx_signed = 1; |
| break; |
| default: |
| break; |
| -- |
| 1.8.1.4 |
| |