optimize repeat(string, n) for repeating single ASCII chars #22462
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Cool! Looks good to me. Looks like the Base string benchmarks won't really see this, so probably not worth running Nanosoldier. |
KristofferC
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While working on #22461, I noticed that nearly all uses of
repeat(string,n)orstring^nwere for repeating strings consisting of a single ASCII character, most commonly" ". This PR speeds up that case by callingmemset.The speedups vary with length
n. Forn=5I get a 50% speedup, forn=20a 3.5x speedup, and forn=1000I get a 41x speedup.