Fix custom hash functions used in pathfinding to not drop bits on 32-…

…bit systems. (CleverRaven#53019)

src/hash_utils.h

@@ -86,6 +86,34 @@ struct range_hash {
     }
 };
 
+namespace hash64_detail
+{
+
+template<typename T>
+std::enable_if_t < sizeof( T ) < 8, T > maybe_mix_bits( std::uint64_t val )
+{
+    std::uint32_t hi = val >> 32;
+    std::uint32_t lo = val;
+    T ret = hi;
+    hash_combine( ret, lo );
+    return ret;
+}
+
+template<typename T>
+std::enable_if_t < sizeof( T ) >= 8, T > maybe_mix_bits( std::uint64_t val )
+{
+    return val;
+}
+
+} // namespace hash64_detail
+
+// hash64 hashes a 64-bit integer, either using the identity function (on 64-bit systems)
+// or using hash_combine on the two 32-bit halves (on 32-bit systems)
+inline std::size_t hash64( std::uint64_t val )
+{
+    return hash64_detail::maybe_mix_bits<std::size_t>( val );
+}
+
 } // namespace cata
 
 #endif // CATA_SRC_HASH_UTILS_H

src/simple_pathfinding.cpp

@@ -8,6 +8,7 @@
 
 #include "coordinates.h"
 #include "enums.h"
+#include "hash_utils.h"
 #include "line.h"
 #include "omdata.h"
 #include "point.h"
@@ -192,10 +193,10 @@ struct node_address {
 
 struct node_address_hasher {
     std::size_t operator()( const node_address &addr ) const {
-        std::size_t val = addr.x;
+        std::uint64_t val = addr.x;
         val = ( val << 16 ) + addr.y;
-        val = ( val << 16 ) + static_cast<int>( addr.z );
-        return std::hash<std::size_t> {}( val );
+        val = ( val << 16 ) + addr.z;
+        return cata::hash64( val );
     }
 };
 

src/vehicle_autodrive.cpp

@@ -21,6 +21,7 @@
 #include "cuboid_rectangle.h"
 #include "debug.h"
 #include "enums.h"
+#include "hash_utils.h"
 #include "map.h"
 #include "map_iterator.h"
 #include "map_memory.h"
@@ -197,10 +198,10 @@ struct node_address {
 
 struct node_address_hasher {
     std::size_t operator()( const node_address &addr ) const {
-        std::int64_t val = addr.x;
+        std::uint64_t val = addr.x;
         val = ( val << 16 ) + addr.y;
         val = ( val << 16 ) + static_cast<int>( addr.facing_dir );
-        return std::hash<int64_t> {}( val );
+        return cata::hash64( val );
     }
 };