I'm at it, rename it to FindInsertedValue.
The only functional change is that newly created instructions are no longer
added to instcombine's worklist, but that is not really necessary anyway (and
I'll commit some improvements next that will completely remove the need).
llvm-svn: 52315
out of instcombine into a new file in libanalysis. This also teaches
ComputeNumSignBits about the number of sign bits in a constantint.
llvm-svn: 51863
Matthijs Kooijman