[LegacyPM] Make the 'addLoop' method accept a loop to add rather than

having it internally allocate the loop.

This is a much more flexible API and necessary in the new loop unswitch
to reasonably support both new and old PMs in common code. It also just
seems like a cleaner separation of concerns.

NFC, this should just be a pure refactoring.

Differential Revision: https://reviews.llvm.org/D33528

llvm-svn: 303834

1 files changed, 6 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Scalar/LoopUnswitch.cpp b/llvm/lib/Transforms/Scalar/LoopUnswitch.cpp
index 6ef1464e933..19daebd0613 100644
--- a/llvm/lib/Transforms/Scalar/LoopUnswitch.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopUnswitch.cpp
@@ -831,7 +831,12 @@ bool LoopUnswitch::UnswitchIfProfitable(Value *LoopCond, Constant *Val,
 /// mapping the blocks with the specified map.
 static Loop *CloneLoop(Loop *L, Loop *PL, ValueToValueMapTy &VM,
                        LoopInfo *LI, LPPassManager *LPM) {
-  Loop &New = LPM->addLoop(PL);
+  Loop &New = *new Loop();
+  if (PL)
+    PL->addChildLoop(&New);
+  else
+    LI->addTopLevelLoop(&New);
+  LPM->addLoop(New);
 
   // Add all of the blocks in L to the new loop.
   for (Loop::block_iterator I = L->block_begin(), E = L->block_end();