[PATCH][GOLD] Fix handling of maximum branch offsets.

[=?big5?b?RG91ZyBLd2FuICjD9q62vHcp?= <dougkwan at google dot com>]

Hi,

    This patch fixes a bug in handling of maximum branch offsets that
caused the linker to crash last week.  The bug was discovered when we
tested gold with a very big binary that happened to contain a THUMB2
long branch with the maximum backward branch offset.  The same problem
also happened in ARM and THUMB long branches.  I also added some
regression tests.

-Doug

2010-02-21  Doug Kwan  <dougkwan@google.com>

        * arm.cc (Arm_relocate_functions::arm_branch_common): Fix bug in
        handling of the maximum backward branch offset.
        (Arm_relocate_functions::thumb_branch_common): Ditto.
        * testsuite/Makefile.am (check_SCRIPTS): Add arm_branch_in_range.sh.
        (check_DATA): Add arm_bl_in_range.stdout, arm_bl_out_of_range.stdout
        thumb_bl_in_range.stdout, thumb_bl_out_of_range.stdout,
        thumb2_bl_in_range.stdout and thumb2_bl_out_of_range.stdout.
        (arm_bl_in_range.stdout, arm_bl_in_range, arm_bl_in_range.o,
        arm_bl_out_of_range.stdout, arm_bl_out_of_range,
        arm_bl_out_of_range.o, thumb_bl_in_range.stdout, thumb_bl_in_range,
        thumb_bl_in_range.o, thumb_bl_out_of_range.stdout,
        thumb_bl_out_of_range thumb_bl_out_of_range.o,
        thumb2_bl_in_range.stdout, thumb2_bl_in_range, thumb2_bl_in_range.o
        thumb2_bl_out_of_range.stdout, thumb2_bl_out_of_range,
        thumb2_bl_out_of_range.o): New rules.
        (MOSTLYCLEANFILES): Add arm_bl_in_range, arm_bl_out_of_range,
        thumb_bl_in_range, thumb_bl_out_of_range, thumb2_bl_in_range and
        thumb2_bl_out_of_range
        * testsuite/Makefile.in: Regenerate.
        * testsuite/arm_bl_in_range.s: New file.
        * testsuite/arm_bl_out_of_range.s: Ditto.
        * testsuite/arm_branch_in_range.sh: Ditto.
        * testsuite/arm_branch_range.t: Ditto.
        * testsuite/thumb2_branch_range.t: Ditto.
        * testsuite/thumb_bl_in_range.s: Ditto.
        * testsuite/thumb_bl_out_of_range.s: Ditto.
        * testsuite/thumb_branch_range.t: Ditto.

Attachment: patch-branch-limits.txt
Description: Text document