[Mesa-dev] [PATCH v2] util: hash_table: move NULL assert to string hashing function

[Ian Romanick]

On 11/28/2017 08:04 AM, Andres Gomez wrote:
> On Tue, 2017-11-28 at 11:18 +0000, Lionel Landwerlin wrote:
>> Hash maps might use pointer keys (which people surely might want to
>> use to hash values) in which case a 0 value is perfectly acceptable.
>> It's only if the hash function needs to deference the pointer that we
> 
> dereference ------------------------------^^^^^^^^^
> 
> This is:
> 
> Reviewed-by: Andres Gomez <agomez at igalia.com>


Also

Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>

>> want to be sure it's not NULL.
>>
>> v2: Add assert in _mesa_fnv32_1a_accumulate_block (Ian)
>>
>> Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
>> ---
>>  src/util/hash_table.c | 4 ++--
>>  src/util/hash_table.h | 2 ++
>>  2 files changed, 4 insertions(+), 2 deletions(-)
>>
>> diff --git a/src/util/hash_table.c b/src/util/hash_table.c
>> index b7421a0144c..8a4de565fcc 100644
>> --- a/src/util/hash_table.c
>> +++ b/src/util/hash_table.c
>> @@ -296,8 +296,6 @@ hash_table_insert(struct hash_table *ht, uint32_t hash,
>>     uint32_t start_hash_address, hash_address;
>>     struct hash_entry *available_entry = NULL;
>>  
>> -   assert(key != NULL);
>> -
>>     if (ht->entries >= ht->max_entries) {
>>        _mesa_hash_table_rehash(ht, ht->size_index + 1);
>>     } else if (ht->deleted_entries + ht->entries >= ht->max_entries) {
>> @@ -481,6 +479,8 @@ _mesa_hash_string(const void *_key)
>>     uint32_t hash = _mesa_fnv32_1a_offset_bias;
>>     const char *key = _key;
>>  
>> +   assert(key != NULL);
>> +
>>     while (*key != 0) {
>>        hash = _mesa_fnv32_1a_accumulate(hash, *key);
>>        key++;
>> diff --git a/src/util/hash_table.h b/src/util/hash_table.h
>> index d3e0758b265..34e9ea6aed3 100644
>> --- a/src/util/hash_table.h
>> +++ b/src/util/hash_table.h
>> @@ -118,6 +118,8 @@ _mesa_fnv32_1a_accumulate_block(uint32_t hash, const void *data, size_t size)
>>  {
>>     const uint8_t *bytes = (const uint8_t *)data;
>>  
>> +   assert(bytes != NULL);
>> +
>>     while (size-- != 0) {
>>        hash ^= *bytes;
>>        hash = hash * 0x01000193;