All CallInsts mayHaveSideEffects

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#1

Does any real code benefit from dead code eliminating read-only functions?
Tom

#2

I'd imagine every get method in any C++ program would benefit from that sort of dead-code elimination. Although simply inlining it might might be all that's really needed.

From: Thomas B. Jablin <tjablin@cs.princeton.edu>
To: LLVM Developers Mailing List <llvmdev@cs.uiuc.edu>
Sent: Mon, May 10, 2010 9:01:09 PM
Subject: Re: [LLVMdev] All CallInsts mayHaveSideEffects

Does any real code benefit from dead code eliminating read-only
functions?

Tom

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May 10, 2010 9:38:47 PM GMT -05:00 US/Canada Eastern
All CallInsts mayHaveSideEffects

This is a known

bug:

http://llvm.org/bugs/show_bug.cgi?id=965

There has been some

discussion about it and similar problems, and the

desire is to perform some

analysis on functions to determine if they

are known to halt trivially, ie

they have no loops and call no other

functions that are not known to

halt.

LLVM still wants to be able to delete calls to trivial read-only

functions.

Reid