search for: emitgepoffset

All: I am looking at a optimization which requires me to lower the getelementptr instruction in llvm. Is there a way to do this in llvm or do i have to write a new pass for this? Thanks a lot for ur help Aparna Kotha Graduate Student Electrical and Computer Engineering department University of Maryland, College Park -- -- Aparna -------------- next part -------------- An HTML attachment

...sallows the following: %a = gep %p, 0x88888888 %b = gep inbounds %a, 1 If %a is within bounds, the "gep inbounds" gives a signed overflow even though it's just a +1 (since 0x88888888 + 1 overflows). So GEP inbounds disables large objects outright. BTW I've always wondered why EmitGEPOffset (http://llvm.org/doxygen/Local_8h_source.html#l00247) doesn't use 'add nsw' if the semantics of GEP inbounds allows that (if my reading of LangRef is correct). > Assuming we're not dealing with inbounds GEPs (e.g. you pass -fwrapv to > clang), I don't see any particu...

Hi, I was looking into the semantics of GEP inbounds and some BasicAA rules and I'm wondering if it's valid in LLVM IR to allocate more than half of the address space with a global variable or an alloca. If that's a scenario want to consider, then we have problems :) Consider this C code (32 bits): #include <string.h> char obj[0x80000008]; char f() { char *p = obj +