search for: d87494

In short: Shall analysis of a SCEV expression be allowed even though part of the IR that was analyzed to build the SCEV expression has been removed? In more detail with background: About a month ago I landed https://reviews.llvm.org/D87494 where SCEV is used to do additional debug-info salvaging in LSR. The idea was to compute (and store) a SCEV of what llvm.dbg.value intrinsics inside the loop refers to and then after LSR transformation compare these SCEVs with the current SCEVs of PHI-nodes of the loop header. If any of these match...