webkitgtk-2.4.9webkitgtk-2.4.9

1 files changed, 197 insertions, 795 deletions

diff --git a/Source/JavaScriptCore/dfg/DFGGraph.cpp b/Source/JavaScriptCore/dfg/DFGGraph.cpp
index 4d013be79..8256007e9 100644
--- a/Source/JavaScriptCore/dfg/DFGGraph.cpp
+++ b/Source/JavaScriptCore/dfg/DFGGraph.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2011, 2013-2015 Apple Inc. All rights reserved.
+ * Copyright (C) 2011, 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -26,27 +26,23 @@
 #include "config.h"
 #include "DFGGraph.h"
 
-#if ENABLE(DFG_JIT)
-
-#include "BytecodeKills.h"
 #include "BytecodeLivenessAnalysisInlines.h"
 #include "CodeBlock.h"
 #include "CodeBlockWithJITType.h"
-#include "DFGBlockWorklist.h"
 #include "DFGClobberSet.h"
 #include "DFGJITCode.h"
 #include "DFGVariableAccessDataDump.h"
 #include "FullBytecodeLiveness.h"
 #include "FunctionExecutableDump.h"
 #include "JIT.h"
-#include "JSLexicalEnvironment.h"
-#include "MaxFrameExtentForSlowPathCall.h"
+#include "JSActivation.h"
 #include "OperandsInlines.h"
-#include "JSCInlines.h"
-#include "StackAlignment.h"
+#include "Operations.h"
 #include <wtf/CommaPrinter.h>
 #include <wtf/ListDump.h>
 
+#if ENABLE(DFG_JIT)
+
 namespace JSC { namespace DFG {
 
 // Creates an array of stringized names.
@@ -62,31 +58,24 @@ Graph::Graph(VM& vm, Plan& plan, LongLivedState& longLivedState)
     , m_codeBlock(m_plan.codeBlock.get())
     , m_profiledBlock(m_codeBlock->alternative())
     , m_allocator(longLivedState.m_allocator)
+    , m_mustHandleAbstractValues(OperandsLike, plan.mustHandleValues)
+    , m_inlineCallFrames(adoptPtr(new InlineCallFrameSet()))
+    , m_hasArguments(false)
     , m_nextMachineLocal(0)
+    , m_machineCaptureStart(std::numeric_limits<int>::max())
     , m_fixpointState(BeforeFixpoint)
-    , m_structureRegistrationState(HaveNotStartedRegistering)
     , m_form(LoadStore)
     , m_unificationState(LocallyUnified)
     , m_refCountState(EverythingIsLive)
 {
     ASSERT(m_profiledBlock);
     
-    m_hasDebuggerEnabled = m_profiledBlock->globalObject()->hasDebugger()
-        || Options::forceDebuggerBytecodeGeneration();
+    for (unsigned i = m_mustHandleAbstractValues.size(); i--;)
+        m_mustHandleAbstractValues[i].setMostSpecific(*this, plan.mustHandleValues[i]);
 }
 
 Graph::~Graph()
 {
-    for (BlockIndex blockIndex = numBlocks(); blockIndex--;) {
-        BasicBlock* block = this->block(blockIndex);
-        if (!block)
-            continue;
-
-        for (unsigned phiIndex = block->phis.size(); phiIndex--;)
-            m_allocator.free(block->phis[phiIndex]);
-        for (unsigned nodeIndex = block->size(); nodeIndex--;)
-            m_allocator.free(block->at(nodeIndex));
-    }
     m_allocator.freeAll();
 }
 
@@ -106,11 +95,11 @@ bool Graph::dumpCodeOrigin(PrintStream& out, const char* prefix, Node* previousN
     if (!previousNode)
         return false;
     
-    if (previousNode->origin.semantic.inlineCallFrame == currentNode->origin.semantic.inlineCallFrame)
+    if (previousNode->codeOrigin.inlineCallFrame == currentNode->codeOrigin.inlineCallFrame)
         return false;
     
-    Vector<CodeOrigin> previousInlineStack = previousNode->origin.semantic.inlineStack();
-    Vector<CodeOrigin> currentInlineStack = currentNode->origin.semantic.inlineStack();
+    Vector<CodeOrigin> previousInlineStack = previousNode->codeOrigin.inlineStack();
+    Vector<CodeOrigin> currentInlineStack = currentNode->codeOrigin.inlineStack();
     unsigned commonSize = std::min(previousInlineStack.size(), currentInlineStack.size());
     unsigned indexOfDivergence = commonSize;
     for (unsigned i = 0; i < commonSize; ++i) {
@@ -143,7 +132,7 @@ bool Graph::dumpCodeOrigin(PrintStream& out, const char* prefix, Node* previousN
 
 int Graph::amountOfNodeWhiteSpace(Node* node)
 {
-    return (node->origin.semantic.inlineDepth() - 1) * 2;
+    return (node->codeOrigin.inlineDepth() - 1) * 2;
 }
 
 void Graph::printNodeWhiteSpace(PrintStream& out, Node* node)
@@ -156,6 +145,7 @@ void Graph::dump(PrintStream& out, const char* prefix, Node* node, DumpContext*
     NodeType op = node->op();
 
     unsigned refCount = node->refCount();
+    bool skipped = !refCount;
     bool mustGenerate = node->mustGenerate();
     if (mustGenerate)
         --refCount;
@@ -177,10 +167,11 @@ void Graph::dump(PrintStream& out, const char* prefix, Node* node, DumpContext*
     // (5) The arguments to the operation. The may be of the form:
     //         @#   - a NodeIndex referencing a prior node in the graph.
     //         arg# - an argument number.
+    //         $#   - the index in the CodeBlock of a constant { for numeric constants the value is displayed | for integers, in both decimal and hex }.
     //         id#  - the index in the CodeBlock of an identifier { if codeBlock is passed to dump(), the string representation is displayed }.
     //         var# - the index of a var on the global object, used by GetGlobalVar/PutGlobalVar operations.
-    out.printf("% 4d:<%c%u:", (int)node->index(), mustGenerate ? '!' : ' ', refCount);
-    if (node->hasResult() && node->hasVirtualRegister() && node->virtualRegister().isValid())
+    out.printf("% 4d:%s<%c%u:", (int)node->index(), skipped ? "  skipped  " : "           ", mustGenerate ? '!' : ' ', refCount);
+    if (node->hasResult() && !skipped && node->hasVirtualRegister())
         out.print(node->virtualRegister());
     else
         out.print("-");
@@ -209,94 +200,88 @@ void Graph::dump(PrintStream& out, const char* prefix, Node* node, DumpContext*
         out.print(comma, node->arrayMode());
     if (node->hasArithMode())
         out.print(comma, node->arithMode());
-    if (node->hasScopeOffset())
-        out.print(comma, node->scopeOffset());
-    if (node->hasDirectArgumentsOffset())
-        out.print(comma, node->capturedArgumentsOffset());
+    if (node->hasVarNumber())
+        out.print(comma, node->varNumber());
     if (node->hasRegisterPointer())
-        out.print(comma, "global", globalObjectFor(node->origin.semantic)->findVariableIndex(node->variablePointer()), "(", RawPointer(node->variablePointer()), ")");
+        out.print(comma, "global", globalObjectFor(node->codeOrigin)->findRegisterIndex(node->registerPointer()), "(", RawPointer(node->registerPointer()), ")");
     if (node->hasIdentifier())
         out.print(comma, "id", node->identifierNumber(), "{", identifiers()[node->identifierNumber()], "}");
-    if (node->hasPromotedLocationDescriptor())
-        out.print(comma, node->promotedLocationDescriptor());
     if (node->hasStructureSet())
         out.print(comma, inContext(node->structureSet(), context));
     if (node->hasStructure())
         out.print(comma, inContext(*node->structure(), context));
-    if (node->hasTransition()) {
-        out.print(comma, pointerDumpInContext(node->transition(), context));
-#if USE(JSVALUE64)
-        out.print(", ID:", node->transition()->next->id());
-#else
-        out.print(", ID:", RawPointer(node->transition()->next));
-#endif
+    if (node->hasStructureTransitionData())
+        out.print(comma, inContext(*node->structureTransitionData().previousStructure, context), " -> ", inContext(*node->structureTransitionData().newStructure, context));
+    if (node->hasFunction()) {
+        out.print(comma, "function(", RawPointer(node->function()), ", ");
+        if (node->function()->inherits(JSFunction::info())) {
+            JSFunction* function = jsCast<JSFunction*>(node->function());
+            if (function->isHostFunction())
+                out.print("<host function>");
+            else
+                out.print(FunctionExecutableDump(function->jsExecutable()));
+        } else
+            out.print("<not JSFunction>");
+        out.print(")");
     }
-    if (node->hasCellOperand()) {
-        if (!node->cellOperand()->value() || !node->cellOperand()->value().isCell())
-            out.print(comma, "invalid cell operand: ", node->cellOperand()->value());
-        else {
-            out.print(comma, pointerDump(node->cellOperand()->value().asCell()));
-            if (node->cellOperand()->value().isCell()) {
-                CallVariant variant(node->cellOperand()->value().asCell());
-                if (ExecutableBase* executable = variant.executable()) {
-                    if (executable->isHostFunction())
-                        out.print(comma, "<host function>");
-                    else if (FunctionExecutable* functionExecutable = jsDynamicCast<FunctionExecutable*>(executable))
-                        out.print(comma, FunctionExecutableDump(functionExecutable));
-                    else
-                        out.print(comma, "<non-function executable>");
-                }
-            }
-        }
+    if (node->hasExecutable()) {
+        if (node->executable()->inherits(FunctionExecutable::info()))
+            out.print(comma, "executable(", FunctionExecutableDump(jsCast<FunctionExecutable*>(node->executable())), ")");
+        else
+            out.print(comma, "executable(not function: ", RawPointer(node->executable()), ")");
+    }
+    if (node->hasFunctionDeclIndex()) {
+        FunctionExecutable* executable = m_codeBlock->functionDecl(node->functionDeclIndex());
+        out.print(comma, FunctionExecutableDump(executable));
+    }
+    if (node->hasFunctionExprIndex()) {
+        FunctionExecutable* executable = m_codeBlock->functionExpr(node->functionExprIndex());
+        out.print(comma, FunctionExecutableDump(executable));
     }
     if (node->hasStorageAccessData()) {
-        StorageAccessData& storageAccessData = node->storageAccessData();
+        StorageAccessData& storageAccessData = m_storageAccessData[node->storageAccessDataIndex()];
         out.print(comma, "id", storageAccessData.identifierNumber, "{", identifiers()[storageAccessData.identifierNumber], "}");
         out.print(", ", static_cast<ptrdiff_t>(storageAccessData.offset));
     }
-    if (node->hasMultiGetByOffsetData()) {
-        MultiGetByOffsetData& data = node->multiGetByOffsetData();
-        out.print(comma, "id", data.identifierNumber, "{", identifiers()[data.identifierNumber], "}");
-        for (unsigned i = 0; i < data.cases.size(); ++i)
-            out.print(comma, inContext(data.cases[i], context));
-    }
-    if (node->hasMultiPutByOffsetData()) {
-        MultiPutByOffsetData& data = node->multiPutByOffsetData();
-        out.print(comma, "id", data.identifierNumber, "{", identifiers()[data.identifierNumber], "}");
-        for (unsigned i = 0; i < data.variants.size(); ++i)
-            out.print(comma, inContext(data.variants[i], context));
-    }
     ASSERT(node->hasVariableAccessData(*this) == node->hasLocal(*this));
     if (node->hasVariableAccessData(*this)) {
-        VariableAccessData* variableAccessData = node->tryGetVariableAccessData();
-        if (variableAccessData) {
-            VirtualRegister operand = variableAccessData->local();
-            out.print(comma, variableAccessData->local(), "(", VariableAccessDataDump(*this, variableAccessData), ")");
-            operand = variableAccessData->machineLocal();
-            if (operand.isValid())
-                out.print(comma, "machine:", operand);
+        VariableAccessData* variableAccessData = node->variableAccessData();
+        VirtualRegister operand = variableAccessData->local();
+        if (operand.isArgument())
+            out.print(comma, "arg", operand.toArgument(), "(", VariableAccessDataDump(*this, variableAccessData), ")");
+        else
+            out.print(comma, "loc", operand.toLocal(), "(", VariableAccessDataDump(*this, variableAccessData), ")");
+        
+        operand = variableAccessData->machineLocal();
+        if (operand.isValid()) {
+            if (operand.isArgument())
+                out.print(comma, "machine:arg", operand.toArgument());
+            else
+                out.print(comma, "machine:loc", operand.toLocal());
         }
     }
-    if (node->hasStackAccessData()) {
-        StackAccessData* data = node->stackAccessData();
-        out.print(comma, data->local);
-        if (data->machineLocal.isValid())
-            out.print(comma, "machine:", data->machineLocal);
-        out.print(comma, data->format);
+    if (node->hasUnlinkedLocal()) {
+        VirtualRegister operand = node->unlinkedLocal();
+        if (operand.isArgument())
+            out.print(comma, "arg", operand.toArgument());
+        else
+            out.print(comma, "loc", operand.toLocal());
     }
-    if (node->hasUnlinkedLocal()) 
-        out.print(comma, node->unlinkedLocal());
     if (node->hasUnlinkedMachineLocal()) {
         VirtualRegister operand = node->unlinkedMachineLocal();
-        if (operand.isValid())
-            out.print(comma, "machine:", operand);
+        if (operand.isValid()) {
+            if (operand.isArgument())
+                out.print(comma, "machine:arg", operand.toArgument());
+            else
+                out.print(comma, "machine:loc", operand.toLocal());
+        }
     }
     if (node->hasConstantBuffer()) {
         out.print(comma);
         out.print(node->startConstant(), ":[");
         CommaPrinter anotherComma;
         for (unsigned i = 0; i < node->numConstants(); ++i)
-            out.print(anotherComma, pointerDumpInContext(freeze(m_codeBlock->constantBuffer(node->startConstant())[i]), context));
+            out.print(anotherComma, inContext(m_codeBlock->constantBuffer(node->startConstant())[i], context));
         out.print("]");
     }
     if (node->hasIndexingType())
@@ -307,36 +292,29 @@ void Graph::dump(PrintStream& out, const char* prefix, Node* node, DumpContext*
         out.print(comma, "^", node->phi()->index());
     if (node->hasExecutionCounter())
         out.print(comma, RawPointer(node->executionCounter()));
-    if (node->hasWatchpointSet())
-        out.print(comma, RawPointer(node->watchpointSet()));
+    if (node->hasVariableWatchpointSet())
+        out.print(comma, RawPointer(node->variableWatchpointSet()));
+    if (node->hasTypedArray())
+        out.print(comma, inContext(JSValue(node->typedArray()), context));
     if (node->hasStoragePointer())
         out.print(comma, RawPointer(node->storagePointer()));
-    if (node->hasObjectMaterializationData())
-        out.print(comma, node->objectMaterializationData());
-    if (node->hasCallVarargsData())
-        out.print(comma, "firstVarArgOffset = ", node->callVarargsData()->firstVarArgOffset);
-    if (node->hasLoadVarargsData()) {
-        LoadVarargsData* data = node->loadVarargsData();
-        out.print(comma, "start = ", data->start, ", count = ", data->count);
-        if (data->machineStart.isValid())
-            out.print(", machineStart = ", data->machineStart);
-        if (data->machineCount.isValid())
-            out.print(", machineCount = ", data->machineCount);
-        out.print(", offset = ", data->offset, ", mandatoryMinimum = ", data->mandatoryMinimum);
-        out.print(", limit = ", data->limit);
-    }
-    if (node->isConstant())
-        out.print(comma, pointerDumpInContext(node->constant(), context));
-    if (node->isJump())
-        out.print(comma, "T:", *node->targetBlock());
+    if (op == JSConstant) {
+        out.print(comma, "$", node->constantNumber());
+        JSValue value = valueOfJSConstant(node);
+        out.print(" = ", inContext(value, context));
+    }
+    if (op == WeakJSConstant)
+        out.print(comma, RawPointer(node->weakConstant()), " (", inContext(*node->weakConstant()->structure(), context), ")");
+    if (node->isBranch() || node->isJump())
+        out.print(comma, "T:", *node->takenBlock());
     if (node->isBranch())
-        out.print(comma, "T:", node->branchData()->taken, ", F:", node->branchData()->notTaken);
+        out.print(comma, "F:", *node->notTakenBlock());
     if (node->isSwitch()) {
         SwitchData* data = node->switchData();
         out.print(comma, data->kind);
         for (unsigned i = 0; i < data->cases.size(); ++i)
-            out.print(comma, inContext(data->cases[i].value, context), ":", data->cases[i].target);
-        out.print(comma, "default:", data->fallThrough);
+            out.print(comma, inContext(data->cases[i].value, context), ":", *data->cases[i].target);
+        out.print(comma, "default:", *data->fallThrough);
     }
     ClobberSet reads;
     ClobberSet writes;
@@ -345,58 +323,43 @@ void Graph::dump(PrintStream& out, const char* prefix, Node* node, DumpContext*
         out.print(comma, "R:", sortedListDump(reads.direct(), ","));
     if (!writes.isEmpty())
         out.print(comma, "W:", sortedListDump(writes.direct(), ","));
-    if (node->origin.isSet()) {
-        out.print(comma, "bc#", node->origin.semantic.bytecodeIndex);
-        if (node->origin.semantic != node->origin.forExit)
-            out.print(comma, "exit: ", node->origin.forExit);
-    }
+    out.print(comma, "bc#", node->codeOrigin.bytecodeIndex);
     
     out.print(")");
 
-    if (node->hasVariableAccessData(*this) && node->tryGetVariableAccessData())
-        out.print("  predicting ", SpeculationDump(node->tryGetVariableAccessData()->prediction()));
-    else if (node->hasHeapPrediction())
-        out.print("  predicting ", SpeculationDump(node->getHeapPrediction()));
+    if (!skipped) {
+        if (node->hasVariableAccessData(*this))
+            out.print("  predicting ", SpeculationDump(node->variableAccessData()->prediction()));
+        else if (node->hasHeapPrediction())
+            out.print("  predicting ", SpeculationDump(node->getHeapPrediction()));
+    }
     
     out.print("\n");
 }
 
-bool Graph::terminalsAreValid()
-{
-    for (BasicBlock* block : blocksInNaturalOrder()) {
-        if (!block->terminal())
-            return false;
-    }
-    return true;
-}
-
 void Graph::dumpBlockHeader(PrintStream& out, const char* prefix, BasicBlock* block, PhiNodeDumpMode phiNodeDumpMode, DumpContext* context)
 {
-    out.print(prefix, "Block ", *block, " (", inContext(block->at(0)->origin.semantic, context), "):", block->isReachable ? "" : " (skipped)", block->isOSRTarget ? " (OSR target)" : "", "\n");
-    if (block->executionCount == block->executionCount)
-        out.print(prefix, "  Execution count: ", block->executionCount, "\n");
+    out.print(prefix, "Block ", *block, " (", inContext(block->at(0)->codeOrigin, context), "): ", block->isReachable ? "" : "(skipped)", block->isOSRTarget ? " (OSR target)" : "", "\n");
     out.print(prefix, "  Predecessors:");
     for (size_t i = 0; i < block->predecessors.size(); ++i)
         out.print(" ", *block->predecessors[i]);
     out.print("\n");
-    out.print(prefix, "  Successors:");
-    if (block->terminal()) {
-        for (BasicBlock* successor : block->successors()) {
-            out.print(" ", *successor);
-            if (m_prePostNumbering.isValid())
-                out.print(" (", m_prePostNumbering.edgeKind(block, successor), ")");
+    if (m_dominators.isValid()) {
+        out.print(prefix, "  Dominated by:");
+        for (size_t i = 0; i < m_blocks.size(); ++i) {
+            if (!m_dominators.dominates(i, block->index))
+                continue;
+            out.print(" #", i);
         }
-    } else
-        out.print(" <invalid>");
-    out.print("\n");
-    if (m_dominators.isValid() && terminalsAreValid()) {
-        out.print(prefix, "  Dominated by: ", m_dominators.dominatorsOf(block), "\n");
-        out.print(prefix, "  Dominates: ", m_dominators.blocksDominatedBy(block), "\n");
-        out.print(prefix, "  Dominance Frontier: ", m_dominators.dominanceFrontierOf(block), "\n");
-        out.print(prefix, "  Iterated Dominance Frontier: ", m_dominators.iteratedDominanceFrontierOf(BlockList(1, block)), "\n");
+        out.print("\n");
+        out.print(prefix, "  Dominates:");
+        for (size_t i = 0; i < m_blocks.size(); ++i) {
+            if (!m_dominators.dominates(block->index, i))
+                continue;
+            out.print(" #", i);
+        }
+        out.print("\n");
     }
-    if (m_prePostNumbering.isValid())
-        out.print(prefix, "  Pre/Post Numbering: ", m_prePostNumbering.preNumber(block), "/", m_prePostNumbering.postNumber(block), "\n");
     if (m_naturalLoops.isValid()) {
         if (const NaturalLoop* loop = m_naturalLoops.headerOf(block)) {
             out.print(prefix, "  Loop header, contains:");
@@ -424,7 +387,7 @@ void Graph::dumpBlockHeader(PrintStream& out, const char* prefix, BasicBlock* bl
             Node* phiNode = block->phis[i];
             if (!phiNode->shouldGenerate() && phiNodeDumpMode == DumpLivePhisOnly)
                 continue;
-            out.print(" @", phiNode->index(), "<", phiNode->local(), ",", phiNode->refCount(), ">->(");
+            out.print(" @", phiNode->index(), "<", phiNode->refCount(), ">->(");
             if (phiNode->child1()) {
                 out.print("@", phiNode->child1()->index());
                 if (phiNode->child2()) {
@@ -446,14 +409,10 @@ void Graph::dump(PrintStream& out, DumpContext* context)
     if (!context)
         context = &myContext;
     
-    out.print("\n");
-    out.print("DFG for ", CodeBlockWithJITType(m_codeBlock, JITCode::DFGJIT), ":\n");
-    out.print("  Fixpoint state: ", m_fixpointState, "; Form: ", m_form, "; Unification state: ", m_unificationState, "; Ref count state: ", m_refCountState, "\n");
-    if (m_form == SSA)
-        out.print("  Argument formats: ", listDump(m_argumentFormats), "\n");
-    else
-        out.print("  Arguments: ", listDump(m_arguments), "\n");
-    out.print("\n");
+    dataLog("\n");
+    dataLog("DFG for ", CodeBlockWithJITType(m_codeBlock, JITCode::DFGJIT), ":\n");
+    dataLog("  Fixpoint state: ", m_fixpointState, "; Form: ", m_form, "; Unification state: ", m_unificationState, "; Ref count state: ", m_refCountState, "\n");
+    dataLog("\n");
     
     Node* lastNode = 0;
     for (size_t b = 0; b < m_blocks.size(); ++b) {
@@ -461,33 +420,22 @@ void Graph::dump(PrintStream& out, DumpContext* context)
         if (!block)
             continue;
         dumpBlockHeader(out, "", block, DumpAllPhis, context);
-        out.print("  States: ", block->cfaStructureClobberStateAtHead);
-        if (!block->cfaHasVisited)
-            out.print(", CurrentlyCFAUnreachable");
-        if (!block->intersectionOfCFAHasVisited)
-            out.print(", CFAUnreachable");
-        out.print("\n");
         switch (m_form) {
         case LoadStore:
         case ThreadedCPS: {
-            out.print("  Vars Before: ");
+            out.print("  vars before: ");
             if (block->cfaHasVisited)
                 out.print(inContext(block->valuesAtHead, context));
             else
                 out.print("<empty>");
             out.print("\n");
-            out.print("  Intersected Vars Before: ");
-            if (block->intersectionOfCFAHasVisited)
-                out.print(inContext(block->intersectionOfPastValuesAtHead, context));
-            else
-                out.print("<empty>");
-            out.print("\n");
-            out.print("  Var Links: ", block->variablesAtHead, "\n");
+            out.print("  var links: ", block->variablesAtHead, "\n");
             break;
         }
             
         case SSA: {
             RELEASE_ASSERT(block->ssa);
+            out.print("  Flush format: ", block->ssa->flushAtHead, "\n");
             out.print("  Availability: ", block->ssa->availabilityAtHead, "\n");
             out.print("  Live: ", nodeListDump(block->ssa->liveAtHead), "\n");
             out.print("  Values: ", nodeMapDump(block->ssa->valuesAtHead, context), "\n");
@@ -498,44 +446,33 @@ void Graph::dump(PrintStream& out, DumpContext* context)
             dump(out, "", block->at(i), context);
             lastNode = block->at(i);
         }
-        out.print("  States: ", block->cfaBranchDirection, ", ", block->cfaStructureClobberStateAtTail);
-        if (!block->cfaDidFinish)
-            out.print(", CFAInvalidated");
-        out.print("\n");
         switch (m_form) {
         case LoadStore:
         case ThreadedCPS: {
-            out.print("  Vars After: ");
+            out.print("  vars after: ");
             if (block->cfaHasVisited)
                 out.print(inContext(block->valuesAtTail, context));
             else
                 out.print("<empty>");
             out.print("\n");
-            out.print("  Var Links: ", block->variablesAtTail, "\n");
+            out.print("  var links: ", block->variablesAtTail, "\n");
             break;
         }
             
         case SSA: {
             RELEASE_ASSERT(block->ssa);
+            out.print("  Flush format: ", block->ssa->flushAtTail, "\n");
             out.print("  Availability: ", block->ssa->availabilityAtTail, "\n");
             out.print("  Live: ", nodeListDump(block->ssa->liveAtTail), "\n");
             out.print("  Values: ", nodeMapDump(block->ssa->valuesAtTail, context), "\n");
             break;
         } }
-        out.print("\n");
+        dataLog("\n");
     }
     
-    out.print("GC Values:\n");
-    for (FrozenValue* value : m_frozenValues) {
-        if (value->pointsToHeap())
-            out.print("    ", inContext(*value, &myContext), "\n");
-    }
-
-    out.print(inContext(watchpoints(), &myContext));
-    
     if (!myContext.isEmpty()) {
-        myContext.dump(out);
-        out.print("\n");
+        myContext.dump(WTF::dataFile());
+        dataLog("\n");
     }
 }
 
@@ -597,113 +534,6 @@ void Graph::resetReachability()
     determineReachability();
 }
 
-namespace {
-
-class RefCountCalculator {
-public:
-    RefCountCalculator(Graph& graph)
-        : m_graph(graph)
-    {
-    }
-    
-    void calculate()
-    {
-        // First reset the counts to 0 for all nodes.
-        for (BlockIndex blockIndex = 0; blockIndex < m_graph.numBlocks(); ++blockIndex) {
-            BasicBlock* block = m_graph.block(blockIndex);
-            if (!block)
-                continue;
-            for (unsigned indexInBlock = block->size(); indexInBlock--;)
-                block->at(indexInBlock)->setRefCount(0);
-            for (unsigned phiIndex = block->phis.size(); phiIndex--;)
-                block->phis[phiIndex]->setRefCount(0);
-        }
-    
-        // Now find the roots:
-        // - Nodes that are must-generate.
-        // - Nodes that are reachable from type checks.
-        // Set their ref counts to 1 and put them on the worklist.
-        for (BlockIndex blockIndex = 0; blockIndex < m_graph.numBlocks(); ++blockIndex) {
-            BasicBlock* block = m_graph.block(blockIndex);
-            if (!block)
-                continue;
-            for (unsigned indexInBlock = block->size(); indexInBlock--;) {
-                Node* node = block->at(indexInBlock);
-                DFG_NODE_DO_TO_CHILDREN(m_graph, node, findTypeCheckRoot);
-                if (!(node->flags() & NodeMustGenerate))
-                    continue;
-                if (!node->postfixRef())
-                    m_worklist.append(node);
-            }
-        }
-        
-        while (!m_worklist.isEmpty()) {
-            while (!m_worklist.isEmpty()) {
-                Node* node = m_worklist.last();
-                m_worklist.removeLast();
-                ASSERT(node->shouldGenerate()); // It should not be on the worklist unless it's ref'ed.
-                DFG_NODE_DO_TO_CHILDREN(m_graph, node, countEdge);
-            }
-            
-            if (m_graph.m_form == SSA) {
-                // Find Phi->Upsilon edges, which are represented as meta-data in the
-                // Upsilon.
-                for (BlockIndex blockIndex = m_graph.numBlocks(); blockIndex--;) {
-                    BasicBlock* block = m_graph.block(blockIndex);
-                    if (!block)
-                        continue;
-                    for (unsigned nodeIndex = block->size(); nodeIndex--;) {
-                        Node* node = block->at(nodeIndex);
-                        if (node->op() != Upsilon)
-                            continue;
-                        if (node->shouldGenerate())
-                            continue;
-                        if (node->phi()->shouldGenerate())
-                            countNode(node);
-                    }
-                }
-            }
-        }
-    }
-    
-private:
-    void findTypeCheckRoot(Node*, Edge edge)
-    {
-        // We may have an "unproved" untyped use for code that is unreachable. The CFA
-        // will just not have gotten around to it.
-        if (edge.isProved() || edge.willNotHaveCheck())
-            return;
-        if (!edge->postfixRef())
-            m_worklist.append(edge.node());
-    }
-    
-    void countNode(Node* node)
-    {
-        if (node->postfixRef())
-            return;
-        m_worklist.append(node);
-    }
-    
-    void countEdge(Node*, Edge edge)
-    {
-        // Don't count edges that are already counted for their type checks.
-        if (!(edge.isProved() || edge.willNotHaveCheck()))
-            return;
-        countNode(edge.node());
-    }
-    
-    Graph& m_graph;
-    Vector<Node*, 128> m_worklist;
-};
-
-} // anonymous namespace
-
-void Graph::computeRefCounts()
-{
-    RefCountCalculator calculator(*this);
-    calculator.calculate();
-}
-
 void Graph::killBlockAndItsContents(BasicBlock* block)
 {
     for (unsigned phiIndex = block->phis.size(); phiIndex--;)
@@ -727,15 +557,29 @@ void Graph::killUnreachableBlocks()
     }
 }
 
+void Graph::resetExitStates()
+{
+    for (BlockIndex blockIndex = 0; blockIndex < m_blocks.size(); ++blockIndex) {
+        BasicBlock* block = m_blocks[blockIndex].get();
+        if (!block)
+            continue;
+        for (unsigned indexInBlock = block->size(); indexInBlock--;)
+            block->at(indexInBlock)->setCanExit(true);
+    }
+}
+
 void Graph::invalidateCFG()
 {
     m_dominators.invalidate();
     m_naturalLoops.invalidate();
-    m_prePostNumbering.invalidate();
 }
 
 void Graph::substituteGetLocal(BasicBlock& block, unsigned startIndexInBlock, VariableAccessData* variableAccessData, Node* newGetLocal)
 {
+    if (variableAccessData->isCaptured()) {
+        // Let CSE worry about this one.
+        return;
+    }
     for (unsigned indexInBlock = startIndexInBlock; indexInBlock < block.size(); ++indexInBlock) {
         Node* node = block[indexInBlock];
         bool shouldContinue = true;
@@ -765,37 +609,26 @@ void Graph::substituteGetLocal(BasicBlock& block, unsigned startIndexInBlock, Va
     }
 }
 
-BlockList Graph::blocksInPreOrder()
+void Graph::addForDepthFirstSort(Vector<BasicBlock*>& result, Vector<BasicBlock*, 16>& worklist, HashSet<BasicBlock*>& seen, BasicBlock* block)
 {
-    BlockList result;
-    BlockWorklist worklist;
-    worklist.push(block(0));
-    while (BasicBlock* block = worklist.pop()) {
-        result.append(block);
-        for (unsigned i = block->numSuccessors(); i--;)
-            worklist.push(block->successor(i));
-    }
-    return result;
+    if (seen.contains(block))
+        return;
+    
+    result.append(block);
+    worklist.append(block);
+    seen.add(block);
 }
 
-BlockList Graph::blocksInPostOrder()
+void Graph::getBlocksInDepthFirstOrder(Vector<BasicBlock*>& result)
 {
-    BlockList result;
-    PostOrderBlockWorklist worklist;
-    worklist.push(block(0));
-    while (BlockWithOrder item = worklist.pop()) {
-        switch (item.order) {
-        case PreOrder:
-            worklist.pushPost(item.block);
-            for (unsigned i = item.block->numSuccessors(); i--;)
-                worklist.push(item.block->successor(i));
-            break;
-        case PostOrder:
-            result.append(item.block);
-            break;
-        }
+    Vector<BasicBlock*, 16> worklist;
+    HashSet<BasicBlock*> seen;
+    addForDepthFirstSort(result, worklist, seen, block(0));
+    while (!worklist.isEmpty()) {
+        BasicBlock* block = worklist.takeLast();
+        for (unsigned i = block->numSuccessors(); i--;)
+            addForDepthFirstSort(result, worklist, seen, block->successor(i));
     }
-    return result;
 }
 
 void Graph::clearReplacements()
@@ -805,22 +638,9 @@ void Graph::clearReplacements()
         if (!block)
             continue;
         for (unsigned phiIndex = block->phis.size(); phiIndex--;)
-            block->phis[phiIndex]->setReplacement(nullptr);
-        for (unsigned nodeIndex = block->size(); nodeIndex--;)
-            block->at(nodeIndex)->setReplacement(nullptr);
-    }
-}
-
-void Graph::clearEpochs()
-{
-    for (BlockIndex blockIndex = numBlocks(); blockIndex--;) {
-        BasicBlock* block = m_blocks[blockIndex].get();
-        if (!block)
-            continue;
-        for (unsigned phiIndex = block->phis.size(); phiIndex--;)
-            block->phis[phiIndex]->setEpoch(Epoch());
+            block->phis[phiIndex]->misc.replacement = 0;
         for (unsigned nodeIndex = block->size(); nodeIndex--;)
-            block->at(nodeIndex)->setEpoch(Epoch());
+            block->at(nodeIndex)->misc.replacement = 0;
     }
 }
 
@@ -831,49 +651,12 @@ void Graph::initializeNodeOwners()
         if (!block)
             continue;
         for (unsigned phiIndex = block->phis.size(); phiIndex--;)
-            block->phis[phiIndex]->owner = block;
-        for (unsigned nodeIndex = block->size(); nodeIndex--;)
-            block->at(nodeIndex)->owner = block;
-    }
-}
-
-void Graph::clearFlagsOnAllNodes(NodeFlags flags)
-{
-    for (BlockIndex blockIndex = numBlocks(); blockIndex--;) {
-        BasicBlock* block = m_blocks[blockIndex].get();
-        if (!block)
-            continue;
-        for (unsigned phiIndex = block->phis.size(); phiIndex--;)
-            block->phis[phiIndex]->clearFlags(flags);
+            block->phis[phiIndex]->misc.owner = block;
         for (unsigned nodeIndex = block->size(); nodeIndex--;)
-            block->at(nodeIndex)->clearFlags(flags);
+            block->at(nodeIndex)->misc.owner = block;
     }
 }
 
-bool Graph::watchCondition(const ObjectPropertyCondition& key)
-{
-    if (!key.isWatchable())
-        return false;
-    
-    m_plan.weakReferences.addLazily(key.object());
-    if (key.hasPrototype())
-        m_plan.weakReferences.addLazily(key.prototype());
-    if (key.hasRequiredValue())
-        m_plan.weakReferences.addLazily(key.requiredValue());
-    
-    m_plan.watchpoints.addLazily(key);
-
-    if (key.kind() == PropertyCondition::Presence)
-        m_safeToLoad.add(std::make_pair(key.object(), key.offset()));
-    
-    return true;
-}
-
-bool Graph::isSafeToLoad(JSObject* base, PropertyOffset offset)
-{
-    return m_safeToLoad.contains(std::make_pair(base, offset));
-}
-
 FullBytecodeLiveness& Graph::livenessFor(CodeBlock* codeBlock)
 {
     HashMap<CodeBlock*, std::unique_ptr<FullBytecodeLiveness>>::iterator iter = m_bytecodeLiveness.find(codeBlock);
@@ -883,7 +666,7 @@ FullBytecodeLiveness& Graph::livenessFor(CodeBlock* codeBlock)
     std::unique_ptr<FullBytecodeLiveness> liveness = std::make_unique<FullBytecodeLiveness>();
     codeBlock->livenessAnalysis().computeFullLiveness(*liveness);
     FullBytecodeLiveness& result = *liveness;
-    m_bytecodeLiveness.add(codeBlock, WTF::move(liveness));
+    m_bytecodeLiveness.add(codeBlock, std::move(liveness));
     return result;
 }
 
@@ -892,40 +675,22 @@ FullBytecodeLiveness& Graph::livenessFor(InlineCallFrame* inlineCallFrame)
     return livenessFor(baselineCodeBlockFor(inlineCallFrame));
 }
 
-BytecodeKills& Graph::killsFor(CodeBlock* codeBlock)
-{
-    HashMap<CodeBlock*, std::unique_ptr<BytecodeKills>>::iterator iter = m_bytecodeKills.find(codeBlock);
-    if (iter != m_bytecodeKills.end())
-        return *iter->value;
-    
-    std::unique_ptr<BytecodeKills> kills = std::make_unique<BytecodeKills>();
-    codeBlock->livenessAnalysis().computeKills(*kills);
-    BytecodeKills& result = *kills;
-    m_bytecodeKills.add(codeBlock, WTF::move(kills));
-    return result;
-}
-
-BytecodeKills& Graph::killsFor(InlineCallFrame* inlineCallFrame)
-{
-    return killsFor(baselineCodeBlockFor(inlineCallFrame));
-}
-
 bool Graph::isLiveInBytecode(VirtualRegister operand, CodeOrigin codeOrigin)
 {
     for (;;) {
-        VirtualRegister reg = VirtualRegister(
-            operand.offset() - codeOrigin.stackOffset());
-        
         if (operand.offset() < codeOrigin.stackOffset() + JSStack::CallFrameHeaderSize) {
+            VirtualRegister reg = VirtualRegister(
+                operand.offset() - codeOrigin.stackOffset());
+            
             if (reg.isArgument()) {
                 RELEASE_ASSERT(reg.offset() < JSStack::CallFrameHeaderSize);
                 
-                if (codeOrigin.inlineCallFrame->isClosureCall
-                    && reg.offset() == JSStack::Callee)
-                    return true;
+                if (!codeOrigin.inlineCallFrame->isClosureCall)
+                    return false;
                 
-                if (codeOrigin.inlineCallFrame->isVarargs()
-                    && reg.offset() == JSStack::ArgumentCount)
+                if (reg.offset() == JSStack::Callee)
+                    return true;
+                if (reg.offset() == JSStack::ScopeChain)
                     return true;
                 
                 return false;
@@ -935,50 +700,24 @@ bool Graph::isLiveInBytecode(VirtualRegister operand, CodeOrigin codeOrigin)
                 reg.offset(), codeOrigin.bytecodeIndex);
         }
         
-        InlineCallFrame* inlineCallFrame = codeOrigin.inlineCallFrame;
-        if (!inlineCallFrame)
+        if (!codeOrigin.inlineCallFrame)
             break;
-
-        // Arguments are always live. This would be redundant if it wasn't for our
-        // op_call_varargs inlining.
-        if (reg.isArgument()
-            && static_cast<size_t>(reg.toArgument()) < inlineCallFrame->arguments.size())
-            return true;
         
-        codeOrigin = inlineCallFrame->caller;
+        codeOrigin = codeOrigin.inlineCallFrame->caller;
     }
     
     return true;
 }
 
-BitVector Graph::localsLiveInBytecode(CodeOrigin codeOrigin)
-{
-    BitVector result;
-    result.ensureSize(block(0)->variablesAtHead.numberOfLocals());
-    forAllLocalsLiveInBytecode(
-        codeOrigin,
-        [&] (VirtualRegister reg) {
-            ASSERT(reg.isLocal());
-            result.quickSet(reg.toLocal());
-        });
-    return result;
-}
-
 unsigned Graph::frameRegisterCount()
 {
-    unsigned result = m_nextMachineLocal + std::max(m_parameterSlots, static_cast<unsigned>(maxFrameExtentForSlowPathCallInRegisters));
-    return roundLocalRegisterCountForFramePointerOffset(result);
-}
-
-unsigned Graph::stackPointerOffset()
-{
-    return virtualRegisterForLocal(frameRegisterCount() - 1).offset();
+    return m_nextMachineLocal + m_parameterSlots;
 }
 
 unsigned Graph::requiredRegisterCountForExit()
 {
     unsigned count = JIT::frameRegisterCountFor(m_profiledBlock);
-    for (InlineCallFrameSet::iterator iter = m_plan.inlineCallFrames->begin(); !!iter; ++iter) {
+    for (InlineCallFrameSet::iterator iter = m_inlineCallFrames->begin(); !!iter; ++iter) {
         InlineCallFrame* inlineCallFrame = *iter;
         CodeBlock* codeBlock = baselineCodeBlockForInlineCallFrame(inlineCallFrame);
         unsigned requiredCount = VirtualRegister(inlineCallFrame->stackOffset).toLocal() + 1 + JIT::frameRegisterCountFor(codeBlock);
@@ -992,384 +731,47 @@ unsigned Graph::requiredRegisterCountForExecutionAndExit()
     return std::max(frameRegisterCount(), requiredRegisterCountForExit());
 }
 
-JSValue Graph::tryGetConstantProperty(
-    JSValue base, const StructureSet& structureSet, PropertyOffset offset)
-{
-    if (!base || !base.isObject())
-        return JSValue();
-    
-    JSObject* object = asObject(base);
-    
-    for (unsigned i = structureSet.size(); i--;) {
-        Structure* structure = structureSet[i];
-        assertIsRegistered(structure);
-        
-        WatchpointSet* set = structure->propertyReplacementWatchpointSet(offset);
-        if (!set || !set->isStillValid())
-            return JSValue();
-        
-        ASSERT(structure->isValidOffset(offset));
-        ASSERT(!structure->isUncacheableDictionary());
-        
-        watchpoints().addLazily(set);
-    }
-    
-    // What follows may require some extra thought. We need this load to load a valid JSValue. If
-    // our profiling makes sense and we're still on track to generate code that won't be
-    // invalidated, then we have nothing to worry about. We do, however, have to worry about
-    // loading - and then using - an invalid JSValue in the case that unbeknownst to us our code
-    // is doomed.
-    //
-    // One argument in favor of this code is that it should definitely work because the butterfly
-    // is always set before the structure. However, we don't currently have a fence between those
-    // stores. It's not clear if this matters, however. We don't ever shrink the property storage.
-    // So, for this to fail, you'd need an access on a constant object pointer such that the inline
-    // caches told us that the object had a structure that it did not *yet* have, and then later,
-    // the object transitioned to that structure that the inline caches had alraedy seen. And then
-    // the processor reordered the stores. Seems unlikely and difficult to test. I believe that
-    // this is worth revisiting but it isn't worth losing sleep over. Filed:
-    // https://bugs.webkit.org/show_bug.cgi?id=134641
-    //
-    // For now, we just do the minimal thing: defend against the structure right now being
-    // incompatible with the getDirect we're trying to do. The easiest way to do that is to
-    // determine if the structure belongs to the proven set.
-    
-    if (!structureSet.contains(object->structure()))
-        return JSValue();
-    
-    return object->getDirect(offset);
-}
-
-JSValue Graph::tryGetConstantProperty(JSValue base, Structure* structure, PropertyOffset offset)
-{
-    return tryGetConstantProperty(base, StructureSet(structure), offset);
-}
-
-JSValue Graph::tryGetConstantProperty(
-    JSValue base, const StructureAbstractValue& structure, PropertyOffset offset)
-{
-    if (structure.isTop() || structure.isClobbered()) {
-        // FIXME: If we just converted the offset to a uid, we could do ObjectPropertyCondition
-        // watching to constant-fold the property.
-        // https://bugs.webkit.org/show_bug.cgi?id=147271
-        return JSValue();
-    }
-    
-    return tryGetConstantProperty(base, structure.set(), offset);
-}
-
-JSValue Graph::tryGetConstantProperty(const AbstractValue& base, PropertyOffset offset)
+JSActivation* Graph::tryGetActivation(Node* node)
 {
-    return tryGetConstantProperty(base.m_value, base.m_structure, offset);
+    if (!node->hasConstant())
+        return 0;
+    return jsDynamicCast<JSActivation*>(valueOfJSConstant(node));
 }
 
-JSValue Graph::tryGetConstantClosureVar(JSValue base, ScopeOffset offset)
+WriteBarrierBase<Unknown>* Graph::tryGetRegisters(Node* node)
 {
-    // This has an awesome concurrency story. See comment for GetGlobalVar in ByteCodeParser.
-    
-    if (!base)
-        return JSValue();
-    
-    JSLexicalEnvironment* activation = jsDynamicCast<JSLexicalEnvironment*>(base);
+    JSActivation* activation = tryGetActivation(node);
     if (!activation)
-        return JSValue();
-    
-    SymbolTable* symbolTable = activation->symbolTable();
-    JSValue value;
-    WatchpointSet* set;
-    {
-        ConcurrentJITLocker locker(symbolTable->m_lock);
-        
-        SymbolTableEntry* entry = symbolTable->entryFor(locker, offset);
-        if (!entry)
-            return JSValue();
-        
-        set = entry->watchpointSet();
-        if (!set)
-            return JSValue();
-        
-        if (set->state() != IsWatched)
-            return JSValue();
-        
-        ASSERT(entry->scopeOffset() == offset);
-        value = activation->variableAt(offset).get();
-        if (!value)
-            return JSValue();
-    }
-    
-    watchpoints().addLazily(set);
-    
-    return value;
-}
-
-JSValue Graph::tryGetConstantClosureVar(const AbstractValue& value, ScopeOffset offset)
-{
-    return tryGetConstantClosureVar(value.m_value, offset);
+        return 0;
+    if (!activation->isTornOff())
+        return 0;
+    return activation->registers();
 }
 
-JSValue Graph::tryGetConstantClosureVar(Node* node, ScopeOffset offset)
+JSArrayBufferView* Graph::tryGetFoldableView(Node* node)
 {
     if (!node->hasConstant())
-        return JSValue();
-    return tryGetConstantClosureVar(node->asJSValue(), offset);
-}
-
-JSArrayBufferView* Graph::tryGetFoldableView(JSValue value)
-{
-    if (!value)
-        return nullptr;
-    JSArrayBufferView* view = jsDynamicCast<JSArrayBufferView*>(value);
-    if (!value)
-        return nullptr;
-    if (!view->length())
-        return nullptr;
-    WTF::loadLoadFence();
-    watchpoints().addLazily(view);
+        return 0;
+    JSArrayBufferView* view = jsDynamicCast<JSArrayBufferView*>(valueOfJSConstant(node));
+    if (!view)
+        return 0;
+    if (!watchpoints().isStillValid(view))
+        return 0;
     return view;
 }
 
-JSArrayBufferView* Graph::tryGetFoldableView(JSValue value, ArrayMode arrayMode)
+JSArrayBufferView* Graph::tryGetFoldableView(Node* node, ArrayMode arrayMode)
 {
     if (arrayMode.typedArrayType() == NotTypedArray)
-        return nullptr;
-    return tryGetFoldableView(value);
-}
-
-void Graph::registerFrozenValues()
-{
-    m_codeBlock->constants().resize(0);
-    m_codeBlock->constantsSourceCodeRepresentation().resize(0);
-    for (FrozenValue* value : m_frozenValues) {
-        if (!value->pointsToHeap())
-            continue;
-        
-        ASSERT(value->structure());
-        ASSERT(m_plan.weakReferences.contains(value->structure()));
-        
-        switch (value->strength()) {
-        case WeakValue: {
-            m_plan.weakReferences.addLazily(value->value().asCell());
-            break;
-        }
-        case StrongValue: {
-            unsigned constantIndex = m_codeBlock->addConstantLazily();
-            // We already have a barrier on the code block.
-            m_codeBlock->constants()[constantIndex].setWithoutWriteBarrier(value->value());
-            break;
-        } }
-    }
-    m_codeBlock->constants().shrinkToFit();
-    m_codeBlock->constantsSourceCodeRepresentation().shrinkToFit();
-}
-
-void Graph::visitChildren(SlotVisitor& visitor)
-{
-    for (FrozenValue* value : m_frozenValues) {
-        visitor.appendUnbarrieredReadOnlyValue(value->value());
-        visitor.appendUnbarrieredReadOnlyPointer(value->structure());
-    }
-    
-    for (BlockIndex blockIndex = numBlocks(); blockIndex--;) {
-        BasicBlock* block = this->block(blockIndex);
-        if (!block)
-            continue;
-        
-        for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex) {
-            Node* node = block->at(nodeIndex);
-            
-            switch (node->op()) {
-            case CheckStructure:
-                for (unsigned i = node->structureSet().size(); i--;)
-                    visitor.appendUnbarrieredReadOnlyPointer(node->structureSet()[i]);
-                break;
-                
-            case NewObject:
-            case ArrayifyToStructure:
-            case NewStringObject:
-                visitor.appendUnbarrieredReadOnlyPointer(node->structure());
-                break;
-                
-            case PutStructure:
-            case AllocatePropertyStorage:
-            case ReallocatePropertyStorage:
-                visitor.appendUnbarrieredReadOnlyPointer(
-                    node->transition()->previous);
-                visitor.appendUnbarrieredReadOnlyPointer(
-                    node->transition()->next);
-                break;
-                
-            case MultiGetByOffset:
-                for (const MultiGetByOffsetCase& getCase : node->multiGetByOffsetData().cases) {
-                    for (Structure* structure : getCase.set())
-                        visitor.appendUnbarrieredReadOnlyPointer(structure);
-                }
-                break;
-                    
-            case MultiPutByOffset:
-                for (unsigned i = node->multiPutByOffsetData().variants.size(); i--;) {
-                    PutByIdVariant& variant = node->multiPutByOffsetData().variants[i];
-                    const StructureSet& set = variant.oldStructure();
-                    for (unsigned j = set.size(); j--;)
-                        visitor.appendUnbarrieredReadOnlyPointer(set[j]);
-                    if (variant.kind() == PutByIdVariant::Transition)
-                        visitor.appendUnbarrieredReadOnlyPointer(variant.newStructure());
-                }
-                break;
-                
-            default:
-                break;
-            }
-        }
-    }
-}
-
-FrozenValue* Graph::freeze(JSValue value)
-{
-    if (UNLIKELY(!value))
-        return FrozenValue::emptySingleton();
-    
-    auto result = m_frozenValueMap.add(JSValue::encode(value), nullptr);
-    if (LIKELY(!result.isNewEntry))
-        return result.iterator->value;
-
-    if (value.isUInt32())
-        m_uint32ValuesInUse.append(value.asUInt32());
-    
-    FrozenValue frozenValue = FrozenValue::freeze(value);
-    if (Structure* structure = frozenValue.structure())
-        registerStructure(structure);
-    
-    return result.iterator->value = m_frozenValues.add(frozenValue);
-}
-
-FrozenValue* Graph::freezeStrong(JSValue value)
-{
-    FrozenValue* result = freeze(value);
-    result->strengthenTo(StrongValue);
-    return result;
-}
-
-void Graph::convertToConstant(Node* node, FrozenValue* value)
-{
-    if (value->structure())
-        assertIsRegistered(value->structure());
-    node->convertToConstant(value);
-}
-
-void Graph::convertToConstant(Node* node, JSValue value)
-{
-    convertToConstant(node, freeze(value));
-}
-
-void Graph::convertToStrongConstant(Node* node, JSValue value)
-{
-    convertToConstant(node, freezeStrong(value));
-}
-
-StructureRegistrationResult Graph::registerStructure(Structure* structure)
-{
-    m_plan.weakReferences.addLazily(structure);
-    if (m_plan.watchpoints.consider(structure))
-        return StructureRegisteredAndWatched;
-    return StructureRegisteredNormally;
-}
-
-void Graph::assertIsRegistered(Structure* structure)
-{
-    // It's convenient to be able to call this with a maybe-null structure.
-    if (!structure)
-        return;
-    
-    DFG_ASSERT(*this, nullptr, m_plan.weakReferences.contains(structure));
-    
-    if (!structure->dfgShouldWatch())
-        return;
-    if (watchpoints().isWatched(structure->transitionWatchpointSet()))
-        return;
-    
-    DFG_CRASH(*this, nullptr, toCString("Structure ", pointerDump(structure), " is watchable but isn't being watched.").data());
-}
-
-NO_RETURN_DUE_TO_CRASH static void crash(
-    Graph& graph, const CString& whileText, const char* file, int line, const char* function,
-    const char* assertion)
-{
-    startCrashing();
-    dataLog("DFG ASSERTION FAILED: ", assertion, "\n");
-    dataLog(file, "(", line, ") : ", function, "\n");
-    dataLog("\n");
-    dataLog(whileText);
-    dataLog("Graph at time of failure:\n");
-    graph.dump();
-    dataLog("\n");
-    dataLog("DFG ASSERTION FAILED: ", assertion, "\n");
-    dataLog(file, "(", line, ") : ", function, "\n");
-    CRASH_WITH_SECURITY_IMPLICATION();
-}
-
-void Graph::handleAssertionFailure(
-    std::nullptr_t, const char* file, int line, const char* function, const char* assertion)
-{
-    crash(*this, "", file, line, function, assertion);
-}
-
-void Graph::handleAssertionFailure(
-    Node* node, const char* file, int line, const char* function, const char* assertion)
-{
-    crash(*this, toCString("While handling node ", node, "\n\n"), file, line, function, assertion);
-}
-
-void Graph::handleAssertionFailure(
-    BasicBlock* block, const char* file, int line, const char* function, const char* assertion)
-{
-    crash(*this, toCString("While handling block ", pointerDump(block), "\n\n"), file, line, function, assertion);
-}
-
-ValueProfile* Graph::valueProfileFor(Node* node)
-{
-    if (!node)
-        return nullptr;
-        
-    CodeBlock* profiledBlock = baselineCodeBlockFor(node->origin.semantic);
-        
-    if (node->hasLocal(*this)) {
-        if (!node->local().isArgument())
-            return nullptr;
-        int argument = node->local().toArgument();
-        Node* argumentNode = m_arguments[argument];
-        if (!argumentNode)
-            return nullptr;
-        if (node->variableAccessData() != argumentNode->variableAccessData())
-            return nullptr;
-        return profiledBlock->valueProfileForArgument(argument);
-    }
-        
-    if (node->hasHeapPrediction())
-        return profiledBlock->valueProfileForBytecodeOffset(node->origin.semantic.bytecodeIndex);
-        
-    return nullptr;
+        return 0;
+    return tryGetFoldableView(node);
 }
 
-MethodOfGettingAValueProfile Graph::methodOfGettingAValueProfileFor(Node* node)
+JSArrayBufferView* Graph::tryGetFoldableViewForChild1(Node* node)
 {
-    if (!node)
-        return MethodOfGettingAValueProfile();
-    
-    if (ValueProfile* valueProfile = valueProfileFor(node))
-        return MethodOfGettingAValueProfile(valueProfile);
-    
-    if (node->op() == GetLocal) {
-        CodeBlock* profiledBlock = baselineCodeBlockFor(node->origin.semantic);
-        
-        return MethodOfGettingAValueProfile::fromLazyOperand(
-            profiledBlock,
-            LazyOperandValueProfileKey(
-                node->origin.semantic.bytecodeIndex, node->local()));
-    }
-    
-    return MethodOfGettingAValueProfile();
+    return tryGetFoldableView(child(node, 0).node(), node->arrayMode());
 }
 
 } } // namespace JSC::DFG
 
-#endif // ENABLE(DFG_JIT)
+#endif