[LLVMdev] ConstantRange in PR1255

[Stepan Dyatkovskiy]

Hi Duncan. I have strange problems with you mailbox, my posts are lost sometimes on this way.
I just want to duplicate answer on your question in this thread:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20120305/138785.html

ConstantRange has a little bit another purposes. It is not a classical range. Yes it has Lower and Upper, but "sub" and "add" operations are differs from "difference" and "union" set operations. But it is still possible to replace Range class with the ConstantRange, though we need to implement classical set operations to do it.

-Stepan.