LPM: Make callers of LPM.deleteLoopFromQueue update LoopInfo directly. NFC

As of r255720, the loop pass manager will DTRT when passes update the
loop info for removed loops, so they no longer need to reach into
LPPassManager APIs to do this kind of transformation. This change very
nearly removes the need for the LPPassManager to even be passed into
loop passes - the only remaining pass that uses the LPM argument is
LoopUnswitch.

llvm-svn: 255797

1 files changed, 4 insertions, 5 deletions

diff --git a/llvm/lib/Transforms/Scalar/LoopDeletion.cpp b/llvm/lib/Transforms/Scalar/LoopDeletion.cpp
index 4971ab8..bc00ff3 100644
--- a/llvm/lib/Transforms/Scalar/LoopDeletion.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopDeletion.cpp
@@ -36,7 +36,7 @@ namespace {
     }
 
     // Possibly eliminate loop L if it is dead.
-    bool runOnLoop(Loop *L, LPPassManager &LPM) override;
+    bool runOnLoop(Loop *L, LPPassManager &) override;
 
     void getAnalysisUsage(AnalysisUsage &AU) const override {
       AU.addRequired<DominatorTreeWrapperPass>();
@@ -132,7 +132,7 @@ bool LoopDeletion::isLoopDead(Loop *L,
 /// so could change the halting/non-halting nature of a program.
 /// NOTE: This entire process relies pretty heavily on LoopSimplify and LCSSA
 /// in order to make various safety checks work.
-bool LoopDeletion::runOnLoop(Loop *L, LPPassManager &LPM) {
+bool LoopDeletion::runOnLoop(Loop *L, LPPassManager &) {
   if (skipOptnoneFunction(L))
     return false;
 
@@ -244,9 +244,8 @@ bool LoopDeletion::runOnLoop(Loop *L, LPPassManager &LPM) {
   for (BasicBlock *BB : blocks)
     loopInfo.removeBlock(BB);
 
-  // The last step is to inform the loop pass manager that we've
-  // eliminated this loop.
-  LPM.deleteLoopFromQueue(L);
+  // The last step is to update LoopInfo now that we've eliminated this loop.
+  loopInfo.updateUnloop(L);
   Changed = true;
 
   ++NumDeleted;