[llvm-commits] CVS: llvm/lib/Transforms/Utils/LoopSimplify.cpp

[Devang Patel]

Changes in directory llvm/lib/Transforms/Utils:

LoopSimplify.cpp updated: 1.91 -> 1.92
---
Log message:

Avoid recursion.


---
Diffs of the changes:  (+13 -6)

 LoopSimplify.cpp |   19 +++++++++++++------
 1 files changed, 13 insertions(+), 6 deletions(-)


Index: llvm/lib/Transforms/Utils/LoopSimplify.cpp
diff -u llvm/lib/Transforms/Utils/LoopSimplify.cpp:1.91 llvm/lib/Transforms/Utils/LoopSimplify.cpp:1.92
--- llvm/lib/Transforms/Utils/LoopSimplify.cpp:1.91	Sun Apr 15 03:47:27 2007
+++ llvm/lib/Transforms/Utils/LoopSimplify.cpp	Fri Apr 20 15:04:37 2007
@@ -407,13 +407,20 @@
 /// AddBlockAndPredsToSet - Add the specified block, and all of its
 /// predecessors, to the specified set, if it's not already in there.  Stop
 /// predecessor traversal when we reach StopBlock.
-static void AddBlockAndPredsToSet(BasicBlock *BB, BasicBlock *StopBlock,
+static void AddBlockAndPredsToSet(BasicBlock *InputBB, BasicBlock *StopBlock,
                                   std::set<BasicBlock*> &Blocks) {
-  if (!Blocks.insert(BB).second) return;  // already processed.
-  if (BB == StopBlock) return;  // Stop here!
-
-  for (pred_iterator I = pred_begin(BB), E = pred_end(BB); I != E; ++I)
-    AddBlockAndPredsToSet(*I, StopBlock, Blocks);
+  std::vector<BasicBlock *> WorkList;
+  WorkList.push_back(InputBB);
+  do {
+    BasicBlock *BB = WorkList.back(); WorkList.pop_back();
+    if (Blocks.insert(BB).second && BB != StopBlock)
+      // If BB is not already processed and it is not a stop block then
+      // insert its predecessor in the work list
+      for (pred_iterator I = pred_begin(BB), E = pred_end(BB); I != E; ++I) {
+        BasicBlock *WBB = *I;
+        WorkList.push_back(WBB);
+      }
+  } while(!WorkList.empty());
 }
 
 /// FindPHIToPartitionLoops - The first part of loop-nestification is to find a