[llvm-dev] StringSwitch efficiency

[Fāng-ruì Sòng via llvm-dev]

This may still need a measurement. StringSwitch takes a StringRef
(const char *Data + size_t Length). The compiler cannot arbitrarily
reference Data[i] if i >= Length. It can do specialization but it
needs to know the valid range.

On Thu, Oct 29, 2020 at 11:53 AM Paul C. Anagnostopoulos via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
>
> Excellent. Then I shall not concern myself with the efficiency of StringSwitch.
>
> At 10/29/2020 02:28 PM, Chris Lattner wrote:
> >Yeah, years ago, the compiler did the right thing through a combination of jump threading and simple redundancy elimination.  StringSwitch does a first character specialization IIRC.
> >
> >-Chris
>
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