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base repository: php/php-src
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  • 5 commits
  • 26 files changed
  • 1 contributor

Commits on Oct 1, 2016

  1. Implement key union 

    Hashtable bucket keys are now represented using a union:

    union zend_bucket_key {
        zend_string *str;
        zend_ulong num;
    }

The bucket->h value is now a pure hash and no longer doubles as
being the integer key value.

The top bit of bucket->h (HT_IS_STR_BIT) determines whether the
key is a string or and integer. We can do this, because the top
bit will always be 1 after hashtable mask application, so its
value does not influence bucket distribution quality.

The zend_hash_integer() function is a bit of a misnomer -- introducing
integer hashing is not as simple as replacing this function.
    @nikic
    nikic committed Oct 1, 2016
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  2. Implement integer hash function 

    For testing using a Murmur64 finalizer.
    @nikic
    nikic committed Oct 1, 2016
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  3. Switch string hash to SipHash-2-4 

    Using dummy key for testing.

After changing hash implementation run to avoid full rebuild:

touch Zend/zend_hash.c Zend/zend_string.c ext/oci8/oci8.c \
ext/opcache/zend_accelerator_hash.c sapi/phpdbg/phpdbg_bp.c \
sapi/phpdbg/phpdbg_cmd.c

Conflicts:
	Zend/zend_string.h
    @nikic
    nikic committed Oct 1, 2016
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  4. Use siphash for integer hashing

    @nikic
    nikic committed Oct 1, 2016
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  5. Use SipHash-1-3 instead of SipHash-2-4

    @nikic
    nikic committed Oct 1, 2016
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