[Isolates] Merge crankshaft (r5922 from bleeding_edge).

src/full-codegen.h

Index: src/full-codegen.h
diff --git a/src/full-codegen.h b/src/full-codegen.h
index 257f20c5023ea6c642d8f44bb03bf9fe895070df..8d9fe2d3322f7cd57f5c91395debf5cb965e342f 100644
--- a/src/full-codegen.h
+++ b/src/full-codegen.h
@@ -31,6 +31,8 @@
 #include "v8.h"
 
 #include "ast.h"
+#include "code-stubs.h"
+#include "codegen.h"
 #include "compiler.h"
 
 namespace v8 {
@@ -66,17 +68,39 @@ class BreakableStatementChecker: public AstVisitor {
 
 class FullCodeGenerator: public AstVisitor {
  public:
+  enum State {
+    NO_REGISTERS,
+    TOS_REG
+  };
+
   explicit FullCodeGenerator(MacroAssembler* masm)
       : masm_(masm),
         info_(NULL),
         nesting_stack_(NULL),
         loop_depth_(0),
-        context_(NULL) {
+        context_(NULL),
+        bailout_entries_(0),
+        stack_checks_(2),  // There's always at least one.
+        forward_bailout_stack_(NULL),
+        forward_bailout_pending_(NULL) {
   }
 
   static bool MakeCode(CompilationInfo* info);
 
   void Generate(CompilationInfo* info);
+  void PopulateDeoptimizationData(Handle<Code> code);
+
+  class StateField : public BitField<State, 0, 8> { };
+  class PcField    : public BitField<unsigned, 8, 32-8> { };
+
+  static const char* State2String(State state) {
+    switch (state) {
+      case NO_REGISTERS: return "NO_REGISTERS";
+      case TOS_REG: return "TOS_REG";
+    }
+    UNREACHABLE();
+    return NULL;
+  }
 
  private:
   class Breakable;
@@ -229,6 +253,24 @@ class FullCodeGenerator: public AstVisitor {
     DISALLOW_COPY_AND_ASSIGN(ForIn);
   };
 
+  // The forward bailout stack keeps track of the expressions that can
+  // bail out to just before the control flow is split in a child
+  // node. The stack elements are linked together through the parent
+  // link when visiting expressions in test contexts after requesting
+  // bailout in child forwarding.
+  class ForwardBailoutStack BASE_EMBEDDED {
+   public:
+    ForwardBailoutStack(Expression* expr, ForwardBailoutStack* parent)
+        : expr_(expr), parent_(parent) { }
+
+    Expression* expr() const { return expr_; }
+    ForwardBailoutStack* parent() const { return parent_; }
+
+   private:
+    Expression* const expr_;
+    ForwardBailoutStack* const parent_;
+  };
+
   enum ConstantOperand {
     kNoConstants,
     kLeftConstant,
@@ -274,19 +316,23 @@ class FullCodeGenerator: public AstVisitor {
   // register.
   MemOperand EmitSlotSearch(Slot* slot, Register scratch);
 
+  // Forward the bailout responsibility for the given expression to
+  // the next child visited (which must be in a test context).
+  void ForwardBailoutToChild(Expression* expr);
+
   void VisitForEffect(Expression* expr) {
     EffectContext context(this);
-    Visit(expr);
+    HandleInNonTestContext(expr, NO_REGISTERS);
   }
 
   void VisitForAccumulatorValue(Expression* expr) {
     AccumulatorValueContext context(this);
-    Visit(expr);
+    HandleInNonTestContext(expr, TOS_REG);
   }
 
   void VisitForStackValue(Expression* expr) {
     StackValueContext context(this);
-    Visit(expr);
+    HandleInNonTestContext(expr, NO_REGISTERS);
   }
 
   void VisitForControl(Expression* expr,
@@ -294,9 +340,15 @@ class FullCodeGenerator: public AstVisitor {
                        Label* if_false,
                        Label* fall_through) {
     TestContext context(this, if_true, if_false, fall_through);
-    Visit(expr);
+    VisitInTestContext(expr);
+    // Forwarding bailouts to children is a one shot operation. It
+    // should have been processed at this point.
+    ASSERT(forward_bailout_pending_ == NULL);
   }
 
+  void HandleInNonTestContext(Expression* expr, State state);
+  void VisitInTestContext(Expression* expr);
+
   void VisitDeclarations(ZoneList<Declaration*>* declarations);
   void DeclareGlobals(Handle<FixedArray> pairs);
 
@@ -310,12 +362,39 @@ class FullCodeGenerator: public AstVisitor {
                          Label* if_false,
                          Label* fall_through);
 
+  // Bailout support.
+  void PrepareForBailout(AstNode* node, State state);
+  void PrepareForBailoutForId(int id, State state);
+
+  // Record a call's return site offset, used to rebuild the frame if the
+  // called function was inlined at the site.
+  void RecordJSReturnSite(Call* call);
+
+  // Prepare for bailout before a test (or compare) and branch.  If
+  // should_normalize, then the following comparison will not handle the
+  // canonical JS true value so we will insert a (dead) test against true at
+  // the actual bailout target from the optimized code. If not
+  // should_normalize, the true and false labels are ignored.
+  void PrepareForBailoutBeforeSplit(State state,
+                                    bool should_normalize,
+                                    Label* if_true,
+                                    Label* if_false);
+
   // Platform-specific code for a variable, constant, or function
   // declaration.  Functions have an initial value.
   void EmitDeclaration(Variable* variable,
                        Variable::Mode mode,
                        FunctionLiteral* function);
 
+  // Platform-specific code for checking the stack limit at the back edge of
+  // a loop.
+  void EmitStackCheck(IterationStatement* stmt);
+  // Record the OSR AST id corresponding to a stack check in the code.
+  void RecordStackCheck(int osr_ast_id);
+  // Emit a table of stack check ids and pcs into the code stream.  Return
+  // the offset of the start of the table.
+  unsigned EmitStackCheckTable();
+
   // Platform-specific return sequence
   void EmitReturnSequence();
 
@@ -471,14 +550,13 @@ class FullCodeGenerator: public AstVisitor {
 
   void VisitForTypeofValue(Expression* expr);
 
-  MacroAssembler* masm_;
-  CompilationInfo* info_;
+  struct BailoutEntry {
+    unsigned id;
+    unsigned pc_and_state;
+  };
 
-  Label return_label_;
-  NestedStatement* nesting_stack_;
-  int loop_depth_;
 
-  class ExpressionContext {
+  class ExpressionContext BASE_EMBEDDED {
    public:
     explicit ExpressionContext(FullCodeGenerator* codegen)
         : masm_(codegen->masm()), old_(codegen->context()), codegen_(codegen) {
@@ -504,7 +582,8 @@ class FullCodeGenerator: public AstVisitor {
 
     // Emit code to convert pure control flow to a pair of unbound labels into
     // the result expected according to this expression context.  The
-    // implementation may decide to bind either of the labels.
+    // implementation will bind both labels unless it's a TestContext, which
+    // won't bind them at this point.
     virtual void Plug(Label* materialize_true,
                       Label* materialize_false) const = 0;
 
@@ -526,12 +605,14 @@ class FullCodeGenerator: public AstVisitor {
                              Label** if_false,
                              Label** fall_through) const = 0;
 
+    virtual void HandleExpression(Expression* expr) const = 0;
+
     // Returns true if we are evaluating only for side effects (ie if the result
-    // will be discarded.
+    // will be discarded).
     virtual bool IsEffect() const { return false; }
 
     // Returns true if we are branching on the value rather than materializing
-    // it.
+    // it.  Only used for asserts.
     virtual bool IsTest() const { return false; }
 
    protected:
@@ -565,6 +646,7 @@ class FullCodeGenerator: public AstVisitor {
                              Label** if_true,
                              Label** if_false,
                              Label** fall_through) const;
+    virtual void HandleExpression(Expression* expr) const;
   };
 
   class StackValueContext : public ExpressionContext {
@@ -588,6 +670,7 @@ class FullCodeGenerator: public AstVisitor {
                              Label** if_true,
                              Label** if_false,
                              Label** fall_through) const;
+    virtual void HandleExpression(Expression* expr) const;
   };
 
   class TestContext : public ExpressionContext {
@@ -626,6 +709,7 @@ class FullCodeGenerator: public AstVisitor {
                              Label** if_true,
                              Label** if_false,
                              Label** fall_through) const;
+    virtual void HandleExpression(Expression* expr) const;
     virtual bool IsTest() const { return true; }
 
    private:
@@ -655,10 +739,20 @@ class FullCodeGenerator: public AstVisitor {
                              Label** if_true,
                              Label** if_false,
                              Label** fall_through) const;
+    virtual void HandleExpression(Expression* expr) const;
     virtual bool IsEffect() const { return true; }
   };
 
+  MacroAssembler* masm_;
+  CompilationInfo* info_;
+  Label return_label_;
+  NestedStatement* nesting_stack_;
+  int loop_depth_;
   const ExpressionContext* context_;
+  ZoneList<BailoutEntry> bailout_entries_;
+  ZoneList<BailoutEntry> stack_checks_;
+  ForwardBailoutStack* forward_bailout_stack_;
+  ForwardBailoutStack* forward_bailout_pending_;
 
   friend class NestedStatement;