commit 27720765ed1a12d7b998afb390d37c69b2c25aec
author Artyom Skrobov <Artyom.Skrobov@arm.com> Tue Sep 23 08:34:41 2014 +0000
committer Artyom Skrobov <Artyom.Skrobov@arm.com> Tue Sep 23 08:34:41 2014 +0000
tree 77ff930fff15c3fc76101b38199dad355be0866b
parent a170697b18c3667a6ea70ea27246e69e202ba3a4

Reverting r214064 and r215650 while investigating a pesky performance regression

llvm-svn: 218296

clang/lib/Analysis/PostOrderCFGView.cpp

diff --git a/clang/lib/Analysis/PostOrderCFGView.cpp b/clang/lib/Analysis/PostOrderCFGView.cpp
index 714292b..5a3c8182 100644
--- a/clang/lib/Analysis/PostOrderCFGView.cpp
+++ b/clang/lib/Analysis/PostOrderCFGView.cpp
@@ -7,7 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// This file implements post order views of the blocks in a CFG.
+// This file implements post order view of the blocks in a CFG.
 //
 //===----------------------------------------------------------------------===//
 
@@ -17,16 +17,14 @@
 
 void PostOrderCFGView::anchor() { }
 
-ReversePostOrderCFGView::ReversePostOrderCFGView(const CFG *cfg) {
+PostOrderCFGView::PostOrderCFGView(const CFG *cfg) {
   Blocks.reserve(cfg->getNumBlockIDs());
   CFGBlockSet BSet(cfg);
-
-  typedef llvm::po_iterator<const CFG*, CFGBlockSet, true> po_iterator;
-
+    
   for (po_iterator I = po_iterator::begin(cfg, BSet),
                    E = po_iterator::end(cfg, BSet); I != E; ++I) {
+    BlockOrder[*I] = Blocks.size() + 1;
     Blocks.push_back(*I);      
-    BlockOrder[*I] = Blocks.size();
   }
 }
 
@@ -49,49 +47,3 @@
   return b1V > b2V;
 }
 
-PostOrderCFGView::PostOrderCFGView(const CFG *cfg) {
-  unsigned size = cfg->getNumBlockIDs();
-  Blocks.reserve(size);
-  CFGBlockSet BSet(cfg);
-
-  typedef llvm::po_iterator<const CFG*, CFGBlockSet, true,
-                            llvm::GraphTraits<llvm::Inverse<const CFG*> >
-                           > po_iterator;
-
-  for (po_iterator I = po_iterator::begin(cfg, BSet),
-                   E = po_iterator::end(cfg, BSet); I != E; ++I) {
-    Blocks.push_back(*I);      
-    BlockOrder[*I] = Blocks.size();
-  }
-
-  // It may be that some blocks are inaccessible going from the CFG exit upwards
-  // (e.g. infinite loops); we still need to add them.
-  for (CFG::const_iterator I = cfg->begin(), E = cfg->end();
-       (Blocks.size() < size) && (I != E); ++I) {
-    const CFGBlock* block = *I;
-    // Add a chain going upwards.
-    while (!BlockOrder.count(block)) {
-      Blocks.push_back(block);
-      BlockOrder[block] = Blocks.size();
-      CFGBlock::const_pred_iterator PI = block->pred_begin(),
-                                    PE = block->pred_end();
-      for (; PI != PE; ++PI) {
-        const CFGBlock* pred = *PI;
-        if (pred && !BlockOrder.count(pred)) {
-          block = pred;
-          break;
-        }
-      }
-      // Chain ends when we couldn't find an unmapped pred.
-      if (PI == PE) break;
-    }
-  }
-}
-
-ReversePostOrderCFGView *
-ReversePostOrderCFGView::create(AnalysisDeclContext &ctx) {
-  const CFG *cfg = ctx.getCFG();
-  if (!cfg)
-    return nullptr;
-  return new ReversePostOrderCFGView(cfg);
-}