* expr.c (force_operand): Ignore flag_pic for detecting pic
        address loads.
        * regclass.c (init_reg_sets_1): Test fixed_regs not flag_pic
        for determining if PIC_OFFSET_TABLE_REGNUM is call-clobbered.
        * resource.c (mark_target_live_regs): Use regs_invalidated_by_call
        instead of open-coded loop.
        * doc/tm.texi (PIC_OFFSET_TABLE_REGNUM): Clarify that it must
        be fixed when in use.

From-SVN: r49329