Require that the hash node must be the first element of the structure to be

managed in a hash table. This gives smaller code and a ~25% size reduction of
the HashNode structure which might become an advantage if many elements are
hashed.


git-svn-id: svn://svn.cc65.org/cc65/trunk@5158 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
uz
2011-08-12 16:13:10 +00:00
parent 762d4d9ea2
commit f571ec44ae
2 changed files with 22 additions and 34 deletions

View File

@@ -50,16 +50,19 @@
/* Hash table node */
/* Hash table node. NOTE: This structure must be the first member of a struct
* that is hashed by the module. Having it first allows to omit a pointer to
* the entry itself, because the C standard guarantees that a pointer to a
* struct can be converted to its first member.
*/
typedef struct HashNode HashNode;
struct HashNode {
HashNode* Next; /* Next entry in hash list */
struct HashTable* Owner; /* Owner table */
unsigned Hash; /* The full hash value */
void* Entry; /* Pointer to user entry data */
};
#define STATIC_HASHNODE_INITIALIZER(Entry) { 0, 0, 0, Entry }
#define STATIC_HASHNODE_INITIALIZER { 0, 0, 0 }
/* Hash table functions */
typedef struct HashFunctions HashFunctions;
@@ -71,9 +74,6 @@ struct HashFunctions {
const void* (*GetKey) (void* Entry);
/* Given a pointer to the user entry data, return a pointer to the key */
HashNode* (*GetHashNode) (void* Entry);
/* Given a pointer to the user entry data, return a pointer to the hash node */
int (*Compare) (const void* Key1, const void* Key2);
/* Compare two keys. The function must return a value less than zero if
* Key1 is smaller than Key2, zero if both are equal, and a value greater
@@ -101,28 +101,16 @@ struct HashTable {
#if defined(HAVE_INLINE)
INLINE void InitHashNode (HashNode* N, void* Entry)
INLINE void InitHashNode (HashNode* N)
/* Initialize a hash node. */
{
N->Next = 0;
N->Owner = 0;
N->Entry = Entry;
}
#else
#define InitHashNode(N, E) \
#define InitHashNode(N) \
(N)->Next = 0, \
(N)->Owner = 0, \
(N)->Entry = (E)
#endif
#if defined(HAVE_INLINE)
INLINE void* HN_GetEntry (HashNode* N)
/* Get the entry from a hash node */
{
return N->Entry;
}
#else
#define HN_GetEntry(N) (N)->Entry
(N)->Owner = 0
#endif