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.

ld/testsuite/
  * ld-xtensa/diff_overflow.exp, * ld-xtensa/diff_overflow1.s,
  * ld-xtensa/diff_overflow2.s: Add test for DIFF* relocation
  signedness and overflow checking.

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 0766b7c4149891bbc9c7c6a369470b83ed131515..3378a4920569dffc10017f578b47c43e483ffa52 100644 (file)
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,10 @@
+2014-05-02  Volodymyr Arbatov  <arbatov@cadence.com>
+           David Weatherford  <weath@cadence.com>
+           Max Filippov  <jcmvbkbc@gmail.com>
+
+       * elf32-xtensa.c (relax_section): treat R_XTENSA_DIFF* relocations as
+       signed.
+
 2014-05-07  Andreas Tobler  <andreast@fgznet.ch>
 
        * config.bfd: Add proper arm config for *-*-freebsd*.

diff --git a/bfd/elf32-xtensa.c b/bfd/elf32-xtensa.c
index 902b99829a9e51afc67c1cd90cb62623e28599fa..adc0a02216e0bfc171cb57eab1c205635a7f772c 100644 (file)
--- 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/ChangeLog b/gas/ChangeLog
index bc2b740edf610d12aa4250b3381035f2bfe13386..0c0d191a69fad3e9317a463bcee850ef266330c6 100644 (file)
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,8 @@
+2014-05-02  Max Filippov  <jcmvbkbc@gmail.com>
+
+       * config/tc-xtensa.c (md_apply_fix): mark BFD_RELOC_XTENSA_DIFF*
+       fixups as signed.
+
 2014-05-07  Andrew Bennett  <andrew.bennett@imgtec.com>
 
        * tc-mips.c (ISA_SUPPORTS_MIPS16E): Add mips32r3, mips32r5, mips64r3

diff --git a/gas/config/tc-xtensa.c b/gas/config/tc-xtensa.c
index 58ace3809e87ab59f403aee933eb8996613d34eb..7547c0a03befff7469c8b7199741f1e7c332a7ef 100644 (file)
--- 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;

diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog
index cc292979d7a66249c780ad3f3c3b01ba488117a1..7564025ea6408b64742adab98e0accbd4de1696b 100644 (file)
--- a/ld/testsuite/ChangeLog
+++ b/ld/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2014-05-02  Max Filippov  <jcmvbkbc@gmail.com>
+
+       * ld-xtensa/diff_overflow.exp, * ld-xtensa/diff_overflow1.s,
+       * ld-xtensa/diff_overflow2.s: Add test for DIFF* relocation
+       signedness and overflow checking.
+
 2014-05-01  Hans-Peter Nilsson  <hp@bitrange.com>
 
        * ld-mmix/sec-11.d, ld-mmix/sec-11.ld, ld-mmix/sec-10.s,

diff --git a/ld/testsuite/ld-xtensa/diff_overflow.exp b/ld/testsuite/ld-xtensa/diff_overflow.exp
new file mode 100644 (file)
index 0000000..89deb38
--- /dev/null
+++ b/ld/testsuite/ld-xtensa/diff_overflow.exp
@@ -0,0 +1,45 @@
+# Test DIFF* relocation signedness and overflow checking
+# By Max Filippov, Cadence Design Systems, Inc.
+#   Copyright (C) 2014 Free Software Foundation, Inc.
+#
+# This file is part of the GNU Binutils.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+# MA 02110-1301, USA.
+
+if ![istarget "xtensa*-*-*"] {
+    return
+}
+
+set testname "DIFF_OVERFLOW"
+
+if ![ld_assemble $as "--text-section-literals $srcdir/$subdir/diff_overflow1.s" tmpdir/diff_overflow1.o] {
+    unresolved $testname
+    return
+}
+if ![ld_assemble $as "--text-section-literals $srcdir/$subdir/diff_overflow2.s" tmpdir/diff_overflow2.o] {
+    unresolved $testname
+    return
+}
+
+set object "tmpdir/diff_overflow"
+
+if ![ld_simple_link $ld $object "tmpdir/diff_overflow1.o tmpdir/diff_overflow2.o"] {
+    verbose -log "failure in ld"
+    fail $testname
+    return
+}
+
+pass $testname

diff --git a/ld/testsuite/ld-xtensa/diff_overflow1.s b/ld/testsuite/ld-xtensa/diff_overflow1.s
new file mode 100644 (file)
index 0000000..38519da
--- /dev/null
+++ b/ld/testsuite/ld-xtensa/diff_overflow1.s
@@ -0,0 +1,27 @@
+       .section .text.f0,"axG",@progbits,f0,comdat
+       .literal_position
+       .literal .L0, 0
+       .align 4
+f0:
+       entry   a1, 32
+       l32r    a2, .L0
+       retw
+
+       .section .text
+       .literal_position
+       .global _start
+_start:
+       entry   a1, 32
+       retw
+
+       .section .text.f1,"axG",@progbits,f1,comdat
+       .literal_position
+       .literal .L1, 0
+       .literal .L2, 0
+       .align 4
+       .global f1
+f1:
+       entry   a1, 32
+       l32r    a2, .L1
+       l32r    a3, .L2
+       retw

diff --git a/ld/testsuite/ld-xtensa/diff_overflow2.s b/ld/testsuite/ld-xtensa/diff_overflow2.s
new file mode 100644 (file)
index 0000000..096ae39
--- /dev/null
+++ b/ld/testsuite/ld-xtensa/diff_overflow2.s
@@ -0,0 +1,22 @@
+       .section .text.f1,"axG",@progbits,f1,comdat
+       .literal_position
+       .literal .L5, 0
+       .align  4
+f4:
+       entry   a1, 32
+.Lf4:
+       l32r    a2, .L5
+       l32r    a2, .L5
+       nop
+       nop
+       retw
+
+       .section .text
+f5:
+       entry   a1, 32
+.Lf5:
+       retw
+
+       .section .debug_frame,"",@progbits
+       .byte   .Lf4 - f4
+       .byte   .Lf5 - f5