[cfe-dev] Clang Slow to Optimize Dead Store Elimination

[Chris Jung]

I have an Objective-C file that’s about 6000 lines long, which is nearly all a NSArray of 550 items, each of which is a NSDictionary with NSString/NSString and NSString/NSNumber key value pairs in literal syntax. This code takes about 0.4s to compile if optimizations are turned off. It takes about 8 minutes to compile if -O1 is turned on. It takes about 13 minutes to compile if "-fobjc-arc" option is given with -O1. The time-report indicates that Dead Store Elimination optimization is taking the majority of the time. Is it worth logging a bug or is that working as intended?

Chris Jung

Embedded Software Engineer
Network and Service Enablement
JDSU
(317) 614-8089
www.jdsu.com<blocked::http://www.jdsu.com/>


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