Add a MathFloor stub generated with TurboFan

src/code-stubs.h

Index: src/code-stubs.h
diff --git a/src/code-stubs.h b/src/code-stubs.h
index 040bf10f774597fed42d95832a349d03631a1899..2c5fd6820f38cfde6e57bcafa8a5e2a0eb09376b 100644
--- a/src/code-stubs.h
+++ b/src/code-stubs.h
@@ -89,6 +89,9 @@ namespace internal {
   V(TransitionElementsKind)                 \
   V(VectorRawKeyedLoad)                     \
   V(VectorRawLoad)                          \
+  /* TurboFanCodeStubs */                   \
+  V(StringLengthTF)                         \
+  V(MathFloor)                              \
   /* IC Handler stubs */                    \
   V(ArrayBufferViewLoadField)               \
   V(LoadConstant)                           \
@@ -152,6 +155,8 @@ namespace internal {
   CODE_STUB_LIST_PPC(V)           \
   CODE_STUB_LIST_MIPS(V)
 
+static const int kHasReturnedMinusZeroSentinel = 1;
+
 // Stub is base classes of all stubs.
 class CodeStub BASE_EMBEDDED {
  public:
@@ -206,6 +211,8 @@ class CodeStub BASE_EMBEDDED {
 
   virtual CallInterfaceDescriptor GetCallInterfaceDescriptor() = 0;
 
+  virtual int GetStackParameterCount() const { return 0; }
+
   virtual void InitializeDescriptor(CodeStubDescriptor* descriptor) {}
 
   static void InitializeDescriptor(Isolate* isolate, uint32_t key,
@@ -348,6 +355,19 @@ struct FakeStubForTesting : public CodeStub {
   Handle<Code> GenerateCode() override;                               \
   DEFINE_CODE_STUB(NAME, SUPER)
 
+#define DEFINE_TURBOFAN_CODE_STUB(NAME, SUPER, DESC, STACK_PARAMS)     \
+ public:                                                               \
+  NAME##Stub(Isolate* isolate) : SUPER(isolate) {}                     \
+  CallInterfaceDescriptor GetCallInterfaceDescriptor() override {      \
+    return DESC(isolate());                                            \
+  };                                                                   \
+  virtual const char* GetFunctionName() const override {               \
+    return #NAME "_STUB";                                              \
+  }                                                                    \
+  int GetStackParameterCount() const override { return STACK_PARAMS; } \
+  Code::StubType GetStubType() const override { return Code::FAST; }   \
+  DEFINE_CODE_STUB(NAME, SUPER)
+
 #define DEFINE_HANDLER_CODE_STUB(NAME, SUPER) \
  public:                                      \
   Handle<Code> GenerateCode() override;       \
@@ -518,6 +538,23 @@ class HydrogenCodeStub : public CodeStub {
 };
 
 
+class TurboFanCodeStub : public CodeStub {
+ public:
+  Code::Kind GetCodeKind() const override { return Code::STUB; }
+
+  // Retrieve the code for the stub. Generate the code if needed.
+  Handle<Code> GenerateCode() override;
+
+  virtual const char* GetFunctionName() const = 0;
+
+ protected:
+  explicit TurboFanCodeStub(Isolate* isolate) : CodeStub(isolate) {}
+
+ private:
+  DEFINE_CODE_STUB_BASE(TurboFanCodeStub, CodeStub);
+};
+
+
 // Helper interface to prepare to/restore after making runtime calls.
 class RuntimeCallHelper {
  public:
@@ -584,6 +621,23 @@ class NopRuntimeCallHelper : public RuntimeCallHelper {
 };
 
 
+class MathFloorStub : public TurboFanCodeStub {
+  DEFINE_TURBOFAN_CODE_STUB(MathFloor, TurboFanCodeStub,
+                            MathRoundVariantDescriptor, 1);
+};
+
+
+class StringLengthTFStub : public TurboFanCodeStub {
+  DEFINE_TURBOFAN_CODE_STUB(StringLengthTF, TurboFanCodeStub, LoadDescriptor,
+                            0);
+
+ public:
+  Code::Kind GetCodeKind() const override { return Code::HANDLER; }
+  InlineCacheState GetICState() const override { return MONOMORPHIC; }
+  ExtraICState GetExtraICState() const override { return Code::LOAD_IC; }
+};
+
+
 class NumberToStringStub final : public HydrogenCodeStub {
  public:
   explicit NumberToStringStub(Isolate* isolate) : HydrogenCodeStub(isolate) {}