A howl on the wind…

A performance comparison of the speed of various ways to compare strings in C++. In this test, all comparisons are of not-equal strings.

Idea from #C++ on QuakeNet, where we always advocate using std::string over various char* functions. I wondered what, if any, the penalty for doing so was.

Sources

• Ticks counted via cycle.h (local mirror)
• Source: speed-string-compare.cpp

Things Tested

• a hand-written naive comparator loop; used as baseline
• string == string
• string == const char*
• strcmp(const char*, const char*) == 0
• strcmp(const char*, string.c_str()) == 0
• strcmp(string.c_str(), string.c_str()) == 0
• string.compare(string)
• string.compare(const char*)
• …and then the whole thing with different offsets.

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