[PM] Remove weird marking of invalidated analyses as "preserved".

This never made a lot of sense. They've been invalidated for one IR unit
but they aren't really preserved in any normal sense. It seemed like it
would be an elegant way of communicating to outer IR units that pass
managers and adaptors had already handled invalidation, but we've since
ended up adding sets that model this more clearly: we're now using
the 'AllAnalysesOn<IRUnitT>' set to handle cases where the trick of
"preserving" invalidated analyses didn't work.

This patch moves to rely on that technique exclusively and removes the
cumbersome API aspect of updating the preserved set when doing
invalidation. This in turn will simplify a *number* of upcoming patches.

This has a side benefit of exposing a number of places where we were
failing to mark the 'AllAnalysesOn<IRUnitT>' set as preserved. This
patch fixes those, and with those fixes shouldn't change any observable
behavior.

llvm-svn: 288023

1 files changed, 8 insertions, 4 deletions

diff --git a/llvm/lib/Analysis/CGSCCPassManager.cpp b/llvm/lib/Analysis/CGSCCPassManager.cpp
index 2b1591cfbcf..63715806c04 100644
--- a/llvm/lib/Analysis/CGSCCPassManager.cpp
+++ b/llvm/lib/Analysis/CGSCCPassManager.cpp
@@ -56,10 +56,8 @@ PassManager<LazyCallGraph::SCC, CGSCCAnalysisManager, LazyCallGraph &,
     assert(C->begin() != C->end() && "Cannot have an empty SCC!");
 
     // Update the analysis manager as each pass runs and potentially
-    // invalidates analyses. We also update the preserved set of analyses
-    // based on what analyses we have already handled the invalidation for
-    // here and don't need to invalidate when finished.
-    PassPA = AM.invalidate(*C, std::move(PassPA));
+    // invalidates analyses.
+    AM.invalidate(*C, PassPA);
 
     // Finally, we intersect the final preserved analyses to compute the
     // aggregate preserved set for this pass manager.
@@ -72,6 +70,12 @@ PassManager<LazyCallGraph::SCC, CGSCCAnalysisManager, LazyCallGraph &,
     // ...getContext().yield();
   }
 
+  // Invaliadtion was handled after each pass in the above loop for the current
+  // SCC. Therefore, the remaining analysis results in the AnalysisManager are
+  // preserved. We mark this with a set so that we don't need to inspect each
+  // one individually.
+  PA.preserve<AllAnalysesOn<LazyCallGraph::SCC>>();
+
   if (DebugLogging)
     dbgs() << "Finished CGSCC pass manager run.\n";