[PATCH][GOLD] Handle bit-1 of THUMB BLX target address correctly.

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

Hi,

    This patch fixes the handling of bit-1 of THUMB BLX target
address, which comes from bit-1 of the branch base address.  The patch
makes the treatment consistent in all parts of the ARM back-end.  The
patch extends the current testing for stubs to cover boundary cases
involving BLX.

-Doug

2010-03-22  Doug Kwan  <dougkwan@google.com>

        * arm.cc (Arm_relocate_functions::abs8,
        Arm_relocate_functions::abs16): Use correct check for overflow
        specified in the ARM ELF specs.
        (Arm_relocate_functions): thumb_branch_common.  Handle bit 1 of branch
        target of a BLX instruction specially.
        (Reloc_stub::stub_type_for_reloc): Ditto.
        (Relocate::relocate): Use symbolic names instead of numeric relocation
        codes to report error.
        (Target_arm::do_relox): Reduce default stub-group size for Cortex-A8
        workaround.
        * testsuite/Makefile.am (check_DATA): add thumb_blx_in_range.stdout,
        thumb_blx_out_of_range.stdout, thumb2_blx_in_range.stdout and
        thumb2_blx_out_of_range.stdout
        (thumb_bl_out_of_range, thumb_bl_out_of_range.o,
        thumb2_bl_out_of_range, thumb2_bl_out_of_range.o): Fix dependenices.
        (thumb_blx_in_range.stdout, thumb_blx_in_range, thumb_blx_in_range.o,
        thumb_blx_out_of_range.stdout, thumb_blx_out_of_range,
        thumb_blx_out_of_range.o, thumb2_blx_in_range.stdout,
        thumb2_blx_in_range, thumb2_blx_in_range.o,
        thumb2_blx_out_of_range.stdout, thumb2_blx_out_of_range,
        thumb2_blx_out_of_range.o): New rules.
        (MOSTLYCLEANFILES): Add thumb_blx_in_range, thumb_blx_out_of_range,
        thumb2_blx_in_range and thumb2_blx_out_of_range.
        * testsuite/Makefile.in: Regenerate.
        * arm_branch_in_range.sh: Add tests for THUMB BLX.
        * testsuite/thumb_blx_in_range.s: New file.
        * testsuite/thumb_blx_out_of_range.s: New file.

Attachment: patch-blx.txt
Description: Text document