From f59daf2104a8e08a49ab9e074e5dcd30fe5f0939 Mon Sep 17 00:00:00 2001
From: Anatol Belski <ab@php.net>
Date: Wed, 22 Oct 2014 15:28:54 +0200
Subject: [PATCH] micro optimized initial hash size calculation
most of the calls are with a size <= 8, so don't even bother any
bitshifts. For the bigger sizes, use an intrinsic (should be extended
with gcc ones though).
---
Zend/zend_hash.c | 20 ++++++++++++++++----
1 file changed, 16 insertions(+), 4 deletions(-)
diff --git a/Zend/zend_hash.c b/Zend/zend_hash.c
index dfd63aa7e1..d3423c842f 100644
--- a/Zend/zend_hash.c
+++ b/Zend/zend_hash.c
@@ -99,7 +99,6 @@ static const uint32_t uninitialized_bucket = {INVALID_IDX};
ZEND_API void _zend_hash_init(HashTable *ht, uint32_t nSize, dtor_func_t pDestructor, zend_bool persistent ZEND_FILE_LINE_DC)
{
- uint32_t i = 3;
SET_INCONSISTENT(HT_OK);
@@ -107,10 +106,23 @@ ZEND_API void _zend_hash_init(HashTable *ht, uint32_t nSize, dtor_func_t pDestru
/* prevent overflow */
ht->nTableSize = 0x80000000;
} else {
- while ((1U << i) < nSize) {
- i++;
+ if (nSize > 8) {
+#ifdef PHP_WIN32
+ ht->nTableSize = 1U << __lzcnt(nSize);
+ if (ht->nTableSize < nSize) {
+ ht->nTableSize <<= 1;
+ }
+#else
+ uint32_t i = 4;
+
+ while ((1U << i) < nSize) {
+ i++;
+ }
+ ht->nTableSize = 1 << i;
+#endif
+ } else {
+ ht->nTableSize = 8;
}
- ht->nTableSize = 1 << i;
}
ht->nTableMask = 0; /* 0 means that ht->arBuckets is uninitialized */
--
2.40.0