From a885c06bdf87a0003c23e15b3467fc7c1d4767d9 Mon Sep 17 00:00:00 2001
From: Devang Patel <dpatel@apple.com>
Date: Tue, 6 Mar 2007 19:00:02 +0000
Subject: [PATCH] Add LPPassManager::insertLoop().

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34979 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/Analysis/LoopPass.h |  6 ++++--
 lib/Analysis/LoopPass.cpp        | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/include/llvm/Analysis/LoopPass.h b/include/llvm/Analysis/LoopPass.h
index fde65c1a5b3..108e8b7a6e1 100644
--- a/include/llvm/Analysis/LoopPass.h
+++ b/include/llvm/Analysis/LoopPass.h
@@ -101,9 +101,11 @@ public:
   }
 
 public:
-  // Delete loop from the loop queue. This is used by Loop pass to inform
-  // Loop Pass Manager that it should skip rest of the passes for this loop.
+  // Delete loop from the loop queue and loop nest (LoopInfo).
   void deleteLoopFromQueue(Loop *L);
+  
+  // Inset loop into the loop nest(LoopInfo) and loop queue(LQ).
+  void insertLoop(Loop *L, Loop *ParentLoop);
 
   // Reoptimize this loop. LPPassManager will re-insert this loop into the
   // queue. This allows LoopPass to change loop nest for the loop. This
diff --git a/lib/Analysis/LoopPass.cpp b/lib/Analysis/LoopPass.cpp
index 4b41a94c70c..0a29c5dae36 100644
--- a/lib/Analysis/LoopPass.cpp
+++ b/lib/Analysis/LoopPass.cpp
@@ -97,10 +97,42 @@ void LPPassManager::deleteLoopFromQueue(Loop *L) {
   }
 }
 
+// Inset loop into loop nest (LoopInfo) and loop queue (LQ).
+void LPPassManager::insertLoop(Loop *L, Loop *ParentLoop) {
+
+  assert (CurrentLoop != L && "Cannot insert CurrentLoop");
+
+  // Insert into loop nest
+  if (ParentLoop)
+    ParentLoop->addChildLoop(L);
+  else
+    LI->addTopLevelLoop(L);
+
+  // Insert L into loop queue
+  if (L == CurrentLoop) 
+    redoLoop(L);
+  else if (!ParentLoop)
+    // This is top level loop. 
+    LQ.push_front(L);
+  else {
+    // Insert L after ParentLoop
+    for (std::deque<Loop *>::iterator I = LQ.begin(),
+           E = LQ.end(); I != E; ++I) {
+      if (*I == ParentLoop) {
+        // deque does not support insert after.
+        ++I;
+        LQ.insert(I, 1, L);
+        break;
+      }
+    }
+  }
+}
+
 // Reoptimize this loop. LPPassManager will re-insert this loop into the
 // queue. This allows LoopPass to change loop nest for the loop. This
 // utility may send LPPassManager into infinite loops so use caution.
 void LPPassManager::redoLoop(Loop *L) {
+  assert (CurrentLoop != L && "Can redo only CurrentLoop");
   redoThisLoop = true;
 }
 
-- 
2.34.1