1 files changed, 5 insertions, 18 deletions
diff --git a/Source/JavaScriptCore/dfg/DFGLoopPreHeaderCreationPhase.cpp b/Source/JavaScriptCore/dfg/DFGLoopPreHeaderCreationPhase.cpp
index 340ef2d18..507e00ff5 100644
--- a/Source/JavaScriptCore/dfg/DFGLoopPreHeaderCreationPhase.cpp
+++ b/Source/JavaScriptCore/dfg/DFGLoopPreHeaderCreationPhase.cpp
@@ -32,17 +32,16 @@
 #include "DFGBlockInsertionSet.h"
 #include "DFGGraph.h"
 #include "DFGPhase.h"
-#include "JSCInlines.h"
+#include "Operations.h"
 #include <wtf/HashMap.h>
 
 namespace JSC { namespace DFG {
 
 BasicBlock* createPreHeader(Graph& graph, BlockInsertionSet& insertionSet, BasicBlock* block)
 {
-    // Don't bother to preserve execution frequencies for now.
-    BasicBlock* preHeader = insertionSet.insertBefore(block, PNaN);
+    BasicBlock* preHeader = insertionSet.insertBefore(block);
     preHeader->appendNode(
-        graph, SpecNone, Jump, block->firstOrigin(), OpInfo(block));
+        graph, SpecNone, Jump, block->at(0)->codeOrigin, OpInfo(block));
     
     for (unsigned predecessorIndex = 0; predecessorIndex < block->predecessors.size(); predecessorIndex++) {
         BasicBlock* predecessor = block->predecessors[predecessorIndex];
@@ -88,23 +87,11 @@ public:
                     existingPreHeader = predecessor;
                     continue;
                 }
-                // We won't have duplicate entries in the predecessors list.
-                DFG_ASSERT(m_graph, nullptr, existingPreHeader != predecessor);
+                if (existingPreHeader == predecessor)
+                    continue;
                 needsNewPreHeader = true;
                 break;
             }
-            
-            // This phase should only be run on a DFG where unreachable blocks have been pruned.
-            // We also don't allow loops back to root. This means that every loop header has got
-            // to have a pre-header.
-            DFG_ASSERT(m_graph, nullptr, existingPreHeader);
-            
-            // We are looking at the predecessors of a loop header. A loop header has to have
-            // some predecessor other than the pre-header. We must have broken critical edges
-            // because that is the DFG SSA convention. Therefore, each predecessor of the loop
-            // header must have only one successor.
-            DFG_ASSERT(m_graph, nullptr, existingPreHeader->terminal()->op() == Jump);
-            
             if (!needsNewPreHeader)
                 continue;