libc/string: simplify strrchr #6229
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pkarashchenko
approved these changes
May 10, 2022
Do not call strlen() here. Old implementation iterated over string twice, if searched for position was at the beginning. This commit changes strrchr() to scan string only once, regardless of input. Signed-off-by: Juha Niskanen <juha.niskanen@haltian.com>
xiaoxiang781216
approved these changes
May 10, 2022
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Summary
Do not call strlen() inside strrchr(). Old implementation iterated over string twice, if searched for position was at the beginning. This commit changes strrchr() to scan string only once, regardless of input.
At least my compiler with -O2 was not smart enough to get rid of strlen() call.
strrchr(s, 0) still works correctly with new implementation.
Impact
Minor optimization / code simplification
Testing