Prepare for allocating the FDE for the current function earlier
than dwarf2out_begin_prologue.

        * dwarf2out.c (fde_table, fde_table_allocated, fde_table_in_use,
        FDE_TABLE_INCREMENT): Replace with...
        (fde_vec): ... this, a new vector.
        (current_fde): Remove.  Replace all users with cfun->fde.
        (output_call_frame_info): Use FOR_EACH_VEC_ELT over fde_vec.
        (size_of_aranges, dwarf2out_finish): Likewise.
        (dwarf2out_alloc_current_fde): Break out from ...
        (dwarf2out_begin_prologue): ... here.
        (dwarf2out_frame_init): Remove.
        * dwarf2cfi.c: Update all users of current_fde.
        (dwarf2out_frame_init): Rename from dwarf2cfi_frame_init.
        * dwarf2out.h: Update decls.
        (dw_fde_node): Add fde_index member.
        * function.h (struct function): Add fde member.

From-SVN: r176018