while ( my( $key1, $val1 ) = each %hash1 ) {
    while ( my( $key2, $val2 ) = each %$val1 ) {
        print( ##join( "\t",
            $key1,
            $key2,
            $hash1{ $key1 }{ $key2 },
            $hash2{ $key1 }{ $key2 },
            $hash3{ $key1 }{ $key2 }
        );
    }
}

##</code><code>##

while ( my( $key1, $val1 ) = each %hash1 ) {
    while ( my( $key2, $val2 ) = each %$val1 ) {
        die 'Autovivify' unless exists $hash1{ $key1 }
                            and exists $hash1{ $key1 }{ $key2 };
        print( join "\t", $key1, $key2, $hash1{ $key1 }{ $key2 }, );
    }
}