[LLVMdev] RFC: Codifying (but not formalizing) the optimization levels in LLVM and Clang

Krzysztof Parzyszek
2013-01-14T16:00:47Z

On 1/14/2013 3:09 AM, Chandler Carruth wrote:
>
> [...] This level should always produce
> binaries at least as fast as quickopt, but they might be both slower to
> compile.

The "always" part cannot really be guaranteed or enforced.  I'd
state it
in terms of intention, i.e. "this level is intended to produce binaries
at least as fast as quickopt".  Otherwise, the wording may imply that it
is a compiler bug if there exists a binary that runs slower at -O2 than
at -O1.

-Krzysztof


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