static uint
hash_key(hashtable_t *table, void *key)
{
uint hash = 0;
if (table->hash_key_func != NULL) {
hash = table->hash_key_func(key);
} else if (table->hashtype == HASH_STRING || table->hashtype == HASH_STRING_NOCASE) {
const char *s = (const char *) key;
char c;
uint i, shift;
uint max_shift = ALIGN_FORWARD(table->table_bits, 8);
/* XXX: share w/ core's hash_value() function */
for (i = 0; s[i] != '\0'; i++) {
c = s[i];
if (table->hashtype == HASH_STRING_NOCASE)
c = (char) tolower(c);
shift = (i % 4) * 8;
if (shift > max_shift)
shift = max_shift;
hash ^= c << shift;
}
} else {
/* HASH_INTPTR, or fallback for HASH_CUSTOM in release build */
ASSERT(table->hashtype == HASH_INTPTR,
"hashtable.c hash_key internal error: invalid hash type");
hash = (uint)(ptr_uint_t) key;
}
return HASH_FUNC_BITS(hash, table->table_bits);
}
/* Lookup an entry by pc and return a pointer to the corresponding entry .
* Returns NULL if no such entry exists.
* Caller must hold htable_mutex if drcontext == NULL.
*/
static trace_head_entry_t *
lookup_trace_head_entry(void *drcontext, void *tag)
{
trace_head_entry_t **table = htable;
trace_head_entry_t *e;
uint hindex;
hindex = (uint) HASH_FUNC_BITS((ptr_uint_t)tag, HASH_BITS);
for (e = table[hindex]; e; e = e->next) {
if (e->tag == tag)
return e;
}
return NULL;
}
/* Caller must hold htable_mutex if drcontext == NULL. */
static trace_head_entry_t *
add_trace_head_entry(void *drcontext, void *tag)
{
trace_head_entry_t **table = htable;
trace_head_entry_t *e;
uint hindex;
e = (trace_head_entry_t *) dr_global_alloc(sizeof(trace_head_entry_t));
e->tag = tag;
e->end_next = 0;
e->size = 0;
e->has_ret = false;
e->is_trace_head = false;
hindex = (uint) HASH_FUNC_BITS((ptr_uint_t)tag, HASH_BITS);
e->next = table[hindex];
table[hindex] = e;
return e;
}
/* Lookup an entry by tag and index and delete it.
* Returns false if no such entry exists.
* Caller must hold htable_mutex if drcontext == NULL.
*/
static bool
remove_trace_head_entry(void *drcontext, void *tag)
{
trace_head_entry_t **table = htable;
trace_head_entry_t *e, *prev;
uint hindex;
hindex = (uint) HASH_FUNC_BITS((ptr_uint_t)tag, HASH_BITS);
for (prev = NULL, e = table[hindex]; e; prev = e, e = e->next) {
if (e->tag == tag) {
if (prev)
prev->next = e->next;
else
table[hindex] = e->next;
dr_global_free(e, sizeof(trace_head_entry_t));
return true;
}
}
return false;
}
static uint
hash_key(hashtable_t *table, void *key)
{
uint hash = 0;
if (table->hash_key_func != NULL) {
hash = table->hash_key_func(key);
} else if (table->hashtype == HASH_STRING || table->hashtype == HASH_STRING_NOCASE) {
const char *s = (const char *) key;
char c;
for (c = *s; c != '\0'; c = *(s++)) {
if (table->hashtype == HASH_STRING_NOCASE)
c = (char) tolower(c);
hash ^= (c << (((s - (const char *)key) %4) * 8));
}
} else {
/* HASH_INTPTR, or fallback for HASH_CUSTOM in release build */
ASSERT(table->hashtype == HASH_INTPTR,
"hashtable.c hash_key internal error: invalid hash type");
hash = (uint)(ptr_uint_t) key;
}
return HASH_FUNC_BITS(hash, table->table_bits);
}