2004-04-17  Paolo Bonzini  <bonzini@gnu.org>

        * opts.c (decode_options): Do not enable flag_rename_registers
        and flag_web at -O3.
        * toplev.c (flag_rename_registers): Initialize
        flag_rename_registers and flag_web to
        AUTODETECT_FLAG_VAR_TRACKING.
        (default_debug_hooks): New global.
        (process_options): Initialize default_debug_hooks.  Warn if
        -fvar-tracking specified but not supported by the current
        debug format.  Do not run var tracking at -O0 or if not
        supported by the current debug format, even if
        -fvar-tracking was given.  If -fno-rename-registers
        is not specified, always run register renaming if var
        tracking is supported by the default debugging information
        format for the target, and we are at -O1 or higher; similarly
        for -fweb, but only at -O2 or higher.
        * doc/invoke.texi (Optimize Options): Document this.

From-SVN: r80789