lookahead map: better method encapsulation in lookahead class

Also extracts the CostMap functions and class in a separate file to keep
things well separated.

Signed-off-by: Alessandro Comodi <[email protected]>

Author: acomodi

vpr/src/place/place_delay_model.cpp

@@ -2,6 +2,7 @@
 #include "place_delay_model.h"
 #include "globals.h"
 #include "router_lookahead_map.h"
+#include "router_lookahead_cost_map.h"
 #include "rr_graph2.h"
 
 #include "timing_place_lookup.h"

vpr/src/route/route_timing.cpp

@@ -37,7 +37,6 @@
 #include "connection_router.h"
 
 #include "router_lookahead_map.h"
-#include "router_lookahead_extended_map.h"
 
 #include "tatum/TimingReporter.hpp"
 

vpr/src/route/router_lookahead.cpp

@@ -1,7 +1,6 @@
 #include "router_lookahead.h"
 
 #include "router_lookahead_map.h"
-#include "router_lookahead_extended_map.h"
 #include "vpr_error.h"
 #include "globals.h"
 #include "route_timing.h"
@@ -14,8 +13,6 @@ static std::unique_ptr<RouterLookahead> make_router_lookahead_object(e_router_lo
         return std::make_unique<ClassicLookahead>();
     } else if (router_lookahead_type == e_router_lookahead::MAP) {
         return std::make_unique<MapLookahead>();
-    } else if (router_lookahead_type == e_router_lookahead::EXTENDED_MAP) {
-        return std::make_unique<ExtendedMapLookahead>();
     } else if (router_lookahead_type == e_router_lookahead::NO_OP) {
         return std::make_unique<NoOpLookahead>();
     }