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

Krzysztof Parzyszek kparzysz at codeaurora.org
Mon Jan 14 08:00:47 PST 2013

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.


Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, 
hosted by The Linux Foundation

More information about the llvm-dev mailing list