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Merged
merged 1 commit into from
Feb 5, 2023
Merged

ext/snmp: use memcpy() instead of memmove() #10498

merged 1 commit into from
Feb 5, 2023

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MaxKellermann
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memcpy() may be faster because it does not have to consider overlapping buffers.

@MaxKellermann
ext/snmp: use memcpy() instead of memmove()
88f8f17 
memcpy() may be faster because it does not have to consider
overlapping buffers.
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devnexen commented Feb 4, 2023

From a good glance, it seems unnecessary to use memmove in those places indeed, even tough memcpy is not systematically faster, despite the overlap checks so there might be not necessarily a huge win, if there is. When the feature had been rewritten around php 5.5 memmove was still kept, so do not know if it was overlooked or if there is a good reason we just do not see. Saying that I do not oppose the changes neither, but let's see what @Girgias has to say about this.

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not necessarily a huge win

True. It's a tiny tiny micro optimization only there to omit the overlap check.

As a compiler implementation detail, the compiler can decide to inline memcpy() more easily than memmove(), because the simplest version of memcpy() is just a single instruction (REP MOVS), while the simplest version of memmove() is much larger than that.

Girgias
Girgias approved these changes Feb 5, 2023
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I don't see how the memory can overlap here

@Girgias Girgias merged commit d3abcae into php:master Feb 5, 2023
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Feb 14, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
0d335e3 
memcpy() may be faster because it does not have to consider
overlapping buffers.
@MaxKellermann MaxKellermann deleted the memcpy branch March 7, 2023 13:25
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Mar 7, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
2fbca4b 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Mar 14, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
3872062 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Apr 12, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
d363cc1 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request May 16, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
dd91761 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Jun 16, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
850414e 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Jul 19, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
c5ddf57 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Aug 1, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
31fc41f 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Aug 3, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
757a202 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Aug 3, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
c2f66cd 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Aug 30, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
2369746 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Oct 2, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
580c413 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Nov 24, 2023
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
5c56ade 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Jan 17, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
9fb6c37 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Jan 17, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
31d749b 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Feb 23, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
84317c0 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Mar 15, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
4ce62c2 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Apr 15, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
a41a977 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request May 8, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
e7220bf 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Jun 5, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
d4402c5 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Jul 3, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
a1731a8 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Jul 30, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
eed558c 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Aug 28, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
3bce525 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Oct 15, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
a025c07 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Oct 30, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
f7ed0c6 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Nov 20, 2024
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
4052020 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Jan 7, 2025
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
653aede 
memcpy() may be faster because it does not have to consider
overlapping buffers.
MaxKellermann added a commit to CM4all/php-src that referenced this pull request Mar 11, 2025
@MaxKellermann
ext/snmp: use memcpy() instead of memmove() (php#10498)
dd851ea 
memcpy() may be faster because it does not have to consider
overlapping buffers.
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@Girgias Girgias Girgias approved these changes

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@MaxKellermann @devnexen @Girgias