Chris Lattner 7efcdb7ca3 Big change to compute logical value numbers for each LiveRange added to an ... Interval. This generalizes the isDefinedOnce mechanism that we used before to help us coallesce ranges that overlap. As part of this, every logical range with a different value is assigned a different number in the interval. For example, for code that looks like this: 0 X = ... 4 X += ... ... N = X We now generate a live interval that contains two ranges: [2,6:0),[6,?:1) reflecting the fact that there are two different values in the range at different positions in the code. Currently we are not using this information at all, so this just slows down liveintervals. In the future, this will change. Note that this change also substantially refactors the joinIntervalsInMachineBB method to merge the cases for virt-virt and phys-virt joining into a single case, adds comments, and makes the code a bit easier to follow. llvm-svn: 15154		2004-07-24 02:59:07 +00:00
llvm	Big change to compute logical value numbers for each LiveRange added to an	2004-07-24 02:59:07 +00:00