Initial SIMDBC interpreter.

runtime/vm/simulator_dbc.cc

Index: runtime/vm/simulator_dbc.cc
diff --git a/runtime/vm/simulator_dbc.cc b/runtime/vm/simulator_dbc.cc
new file mode 100644
index 0000000000000000000000000000000000000000..fd48ea500ccfead7feeacdcebefb29958d9c41e8
--- /dev/null
+++ b/runtime/vm/simulator_dbc.cc
@@ -0,0 +1,1737 @@
+// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+#include <setjmp.h>  // NOLINT
+#include <stdlib.h>
+
+#include "vm/globals.h"
+#if defined(TARGET_ARCH_DBC)
+
+#if !defined(USING_SIMULATOR)
+#error "DBC is a simulated architecture"
+#endif
+
+#include "vm/simulator.h"
+
+#include "vm/assembler.h"
+#include "vm/compiler.h"
+#include "vm/constants_dbc.h"
+#include "vm/cpu.h"
+#include "vm/dart_entry.h"
+#include "vm/debugger.h"
+#include "vm/disassembler.h"
+#include "vm/lockers.h"
+#include "vm/native_arguments.h"
+#include "vm/native_entry.h"
+#include "vm/object.h"
+#include "vm/object_store.h"
+#include "vm/os_thread.h"
+#include "vm/stack_frame.h"
+
+namespace dart {
+
+DEFINE_FLAG(uint64_t, trace_sim_after, ULLONG_MAX,
+            "Trace simulator execution after instruction count reached.");
+DEFINE_FLAG(uint64_t, stop_sim_at, ULLONG_MAX,
+            "Instruction address or instruction count to stop simulator at.");
+
+// SimulatorSetjmpBuffer are linked together, and the last created one
+// is referenced by the Simulator. When an exception is thrown, the exception
+// runtime looks at where to jump and finds the corresponding
+// SimulatorSetjmpBuffer based on the stack pointer of the exception handler.
+// The runtime then does a Longjmp on that buffer to return to the simulator.
+class SimulatorSetjmpBuffer {
+ public:
+  void Longjmp() {
+    // "This" is now the last setjmp buffer.
+    simulator_->set_last_setjmp_buffer(this);
+    longjmp(buffer_, 1);
+  }
+
+  explicit SimulatorSetjmpBuffer(Simulator* sim) {
+    simulator_ = sim;
+    link_ = sim->last_setjmp_buffer();
+    sim->set_last_setjmp_buffer(this);
+    top_ = sim->top_;
+    base_ = sim->base_;
+  }
+
+  ~SimulatorSetjmpBuffer() {
+    ASSERT(simulator_->last_setjmp_buffer() == this);
+    simulator_->set_last_setjmp_buffer(link_);
+  }
+
+  SimulatorSetjmpBuffer* link() { return link_; }
+
+  uintptr_t* top() const { return top_; }
+  uword base() const { return reinterpret_cast<uword>(base_); }
+
+  jmp_buf buffer_;
+
+ private:
+  uintptr_t* top_;
+  uintptr_t* base_;
+  Simulator* simulator_;
+  SimulatorSetjmpBuffer* link_;
+
+  friend class Simulator;
+};
+
+
+DART_FORCE_INLINE static RawObject** SavedCallerFP(RawObject** FP) {
+  return reinterpret_cast<RawObject**>(FP[kSavedCallerFpSlotFromFp]);
+}
+
+
+DART_FORCE_INLINE static RawCode* FrameCode(RawObject** FP) {
+  return static_cast<RawCode*>(FP[kPcMarkerSlotFromFp]);
+}
+
+
+DART_FORCE_INLINE static void SetFrameCode(RawObject** FP, RawCode* code) {
+  FP[kPcMarkerSlotFromFp] = code;
+}
+
+
+DART_FORCE_INLINE static RawObject** FrameArguments(RawObject** FP,
+                                                 intptr_t argc) {
+  return FP - (kDartFrameFixedSize + argc);
+}
+
+
+class SimulatorHelpers {
+ public:
+  DART_FORCE_INLINE static RawSmi* GetClassIdAsSmi(RawObject* obj) {
+    return Smi::New(obj->IsHeapObject() ? obj->GetClassId() : kSmiCid);
+  }
+
+  DART_FORCE_INLINE static intptr_t GetClassId(RawObject* obj) {
+    return obj->IsHeapObject() ? obj->GetClassId() : kSmiCid;
+  }
+
+  DART_FORCE_INLINE static void IncrementUsageCounter(RawICData* icdata) {
+    reinterpret_cast<RawFunction*>(icdata->ptr()->owner_)
+        ->ptr()
+        ->usage_counter_++;
+  }
+
+  DART_FORCE_INLINE static bool IsStrictEqualWithNumberCheck(RawObject* lhs,
+                                                             RawObject* rhs) {
+    if (lhs == rhs) {
+      return true;
+    }
+
+    if (lhs->IsHeapObject() && rhs->IsHeapObject()) {
+      const intptr_t lhs_cid = lhs->GetClassId();
+      const intptr_t rhs_cid = rhs->GetClassId();
+      if (lhs_cid == rhs_cid) {
+        switch (lhs_cid) {
+          case kDoubleCid:
+            return (bit_cast<uint64_t, double>(
+                        static_cast<RawDouble*>(lhs)->ptr()->value_) ==
+                    bit_cast<uint64_t, double>(
+                        static_cast<RawDouble*>(rhs)->ptr()->value_));
+
+          case kMintCid:
+            return (static_cast<RawMint*>(lhs)->ptr()->value_ ==
+                    static_cast<RawMint*>(rhs)->ptr()->value_);
+
+          case kBigintCid:
+            return (DLRT_BigintCompare(static_cast<RawBigint*>(lhs),
+                                       static_cast<RawBigint*>(rhs)) == 0);
+        }
+      }
+    }
+
+    return false;
+  }
+
+  template <typename T>
+  DART_FORCE_INLINE static T* Untag(T* tagged) {
+    return tagged->ptr();
+  }
+
+  static bool ObjectArraySetIndexed(Thread* thread, RawObject** B,
+                                    RawObject** result) {
+    if (thread->isolate()->type_checks()) {
+      return false;
+    }
+
+    RawObject** args = FrameArguments(B, 3);
+    RawSmi* index = static_cast<RawSmi*>(args[1]);
+    RawArray* array = static_cast<RawArray*>(args[0]);
+    if (!index->IsHeapObject() && reinterpret_cast<intptr_t>(index) >= 0 &&
+        reinterpret_cast<intptr_t>(index) <
+            reinterpret_cast<intptr_t>(array->ptr()->length_)) {
+      array->StorePointer(array->ptr()->data() + Smi::Value(index), args[2]);
+      return true;
+    }
+    return false;
+  }
+
+  static bool ObjectArrayGetIndexed(Thread* thread, RawObject** B,
+                                    RawObject** result) {
+    RawObject** args = FrameArguments(B, 2);
+    RawSmi* index = static_cast<RawSmi*>(args[1]);
+    RawArray* array = static_cast<RawArray*>(args[0]);
+    if (!index->IsHeapObject() && reinterpret_cast<intptr_t>(index) >= 0 &&
+        reinterpret_cast<intptr_t>(index) <
+            reinterpret_cast<intptr_t>(array->ptr()->length_)) {
+      *result = array->ptr()->data()[Smi::Value(index)];
+      return true;
+    }
+    return false;
+  }
+
+  static bool GrowableArraySetIndexed(Thread* thread, RawObject** B,
+                                      RawObject** result) {
+    if (thread->isolate()->type_checks()) {
+      return false;
+    }
+
+    RawObject** args = FrameArguments(B, 3);
+    RawSmi* index = static_cast<RawSmi*>(args[1]);
+    RawGrowableObjectArray* array =
+        static_cast<RawGrowableObjectArray*>(args[0]);
+    if (!index->IsHeapObject() && reinterpret_cast<intptr_t>(index) >= 0 &&
+        reinterpret_cast<intptr_t>(index) <
+            reinterpret_cast<intptr_t>(array->ptr()->length_)) {
+      RawArray* data = array->ptr()->data_;
+      data->StorePointer(data->ptr()->data() + Smi::Value(index), args[2]);
+      return true;
+    }
+    return false;
+  }
+
+  static bool GrowableArrayGetIndexed(Thread* thread, RawObject** B,
+                                      RawObject** result) {
+    RawObject** args = FrameArguments(B, 2);
+    RawSmi* index = static_cast<RawSmi*>(args[1]);
+    RawGrowableObjectArray* array =
+        static_cast<RawGrowableObjectArray*>(args[0]);
+    if (!index->IsHeapObject() && reinterpret_cast<intptr_t>(index) >= 0 &&
+        reinterpret_cast<intptr_t>(index) <
+            reinterpret_cast<intptr_t>(array->ptr()->length_)) {
+      *result = array->ptr()->data_->ptr()->data()[Smi::Value(index)];
+      return true;
+    }
+    return false;
+  }
+};
+
+
+DART_FORCE_INLINE static uint32_t* SavedCallerPC(RawObject** FP) {
+  return reinterpret_cast<uint32_t*>(FP[kSavedCallerPcSlotFromFp]);
+}
+
+
+DART_FORCE_INLINE static RawFunction* FrameFunction(RawObject** FP) {
+  RawFunction* function = static_cast<RawFunction*>(FP[kFunctionSlotFromFp]);
+  ASSERT(SimulatorHelpers::GetClassId(function) == kFunctionCid);
+  return function;
+}
+
+
+IntrinsicHandler Simulator::intrinsics_[Simulator::kIntrinsicCount];
+
+
+// Synchronization primitives support.
+void Simulator::InitOnce() {
+  for (intptr_t i = 0; i < kIntrinsicCount; i++) {
+    intrinsics_[i] = 0;
+  }
+
+  intrinsics_[kObjectArraySetIndexedIntrinsic] =
+      SimulatorHelpers::ObjectArraySetIndexed;
+  intrinsics_[kObjectArrayGetIndexedIntrinsic] =
+      SimulatorHelpers::ObjectArrayGetIndexed;
+  intrinsics_[kGrowableArraySetIndexedIntrinsic] =
+      SimulatorHelpers::GrowableArraySetIndexed;
+  intrinsics_[kGrowableArrayGetIndexedIntrinsic] =
+      SimulatorHelpers::GrowableArrayGetIndexed;
+}
+
+
+Simulator::Simulator() {
+  // Setup simulator support first. Some of this information is needed to
+  // setup the architecture state.
+  // We allocate the stack here, the size is computed as the sum of
+  // the size specified by the user and the buffer space needed for
+  // handling stack overflow exceptions. To be safe in potential
+  // stack underflows we also add some underflow buffer space.
+  stack_ = new uintptr_t[(OSThread::GetSpecifiedStackSize() +
+                          OSThread::kStackSizeBuffer +
+                          kSimulatorStackUnderflowSize) /
+                         sizeof(uintptr_t)];
+  base_ = top_ = stack_;
+  last_setjmp_buffer_ = NULL;
+  top_exit_frame_info_ = 0;
+}
+
+
+Simulator::~Simulator() {
+  delete[] stack_;
+  Isolate* isolate = Isolate::Current();
+  if (isolate != NULL) {
+    isolate->set_simulator(NULL);
+  }
+}
+
+
+// Get the active Simulator for the current isolate.
+Simulator* Simulator::Current() {
+  Simulator* simulator = Isolate::Current()->simulator();
+  if (simulator == NULL) {
+    simulator = new Simulator();
+    Isolate::Current()->set_simulator(simulator);
+  }
+  return simulator;
+}
+
+
+// Returns the top of the stack area to enable checking for stack pointer
+// validity.
+uword Simulator::StackTop() const {
+  // To be safe in potential stack underflows we leave some buffer above and
+  // set the stack top.
+  return StackBase() +
+         (OSThread::GetSpecifiedStackSize() + OSThread::kStackSizeBuffer);
+}
+
+
+// Calls into the Dart runtime are based on this interface.
+typedef void (*SimulatorRuntimeCall)(NativeArguments arguments);
+
+// Calls to leaf Dart runtime functions are based on this interface.
+typedef int32_t (*SimulatorLeafRuntimeCall)(int32_t r0, int32_t r1, int32_t r2,
+                                            int32_t r3);
+
+// Calls to leaf float Dart runtime functions are based on this interface.
+typedef double (*SimulatorLeafFloatRuntimeCall)(double d0, double d1);
+
+// Calls to native Dart functions are based on this interface.
+typedef void (*SimulatorBootstrapNativeCall)(NativeArguments* arguments);
+typedef void (*SimulatorNativeCall)(NativeArguments* arguments, uword target);
+
+
+void Simulator::Exit(Thread* thread, RawObject** base, RawObject** frame,
+                     uint32_t* pc) {
+  frame[0] = Function::null();
+  frame[1] = Code::null();
+  frame[2] = reinterpret_cast<RawObject*>(pc);
+  frame[3] = reinterpret_cast<RawObject*>(base);
+  base_ = top_ = reinterpret_cast<uintptr_t*>(frame + kDartFrameFixedSize);
+  thread->set_top_exit_frame_info(reinterpret_cast<uword>(top_));
+}
+
+
+#if defined(__has_builtin)
+#if __has_builtin(__builtin_smul_overflow)
+#define HAS_MUL_OVERFLOW
+#endif
+#if __has_builtin(__builtin_sadd_overflow)
+#define HAS_ADD_OVERFLOW
+#endif
+#if __has_builtin(__builtin_ssub_overflow)
+#define HAS_SUB_OVERFLOW
+#endif
+#endif
+
+
+DART_FORCE_INLINE static int32_t SignedAddWithOverflow(int32_t lhs, int32_t rhs,
+                                                       intptr_t* out) {
+  int32_t res = 1;
+#if defined(HAS_ADD_OVERFLOW)
+  res = __builtin_sadd_overflow(lhs, rhs, out);
+#elif defined(__i386__)
+  asm volatile(
+      "add %2, %1\n"
+      "jo 1f;\n"
+      "xor %0, %0\n"
+      "mov %1, 0(%3)\n"
+      "1: "
+      : "+r"(res), "+r"(lhs)
+      : "r"(rhs), "r"(out)
+      : "cc");
+#elif defined(__arm__)
+  asm volatile(
+      "adds %1, %1, %2;\n"
+      "bvs 1f;\n"
+      "mov %0, $0;\n"
+      "str %1, [%3, #0]\n"
+      "1:"
+      : "+r"(res), "+r"(lhs)
+      : "r"(rhs), "r"(out)
+      : "cc", "r12");
+#else
+#error "Unsupported platform"
+#endif
+  return res;
+}
+
+
+DART_FORCE_INLINE static int32_t SignedSubWithOverflow(int32_t lhs, int32_t rhs,
+                                                       intptr_t* out) {
+  int32_t res = 1;
+#if defined(HAS_SUB_OVERFLOW)
+  res = __builtin_ssub_overflow(lhs, rhs, out);
+#elif defined(__i386__)
+  asm volatile(
+      "sub %2, %1\n"
+      "jo 1f;\n"
+      "xor %0, %0\n"
+      "mov %1, 0(%3)\n"
+      "1: "
+      : "+r"(res), "+r"(lhs)
+      : "r"(rhs), "r"(out)
+      : "cc");
+#elif defined(__arm__)
+  asm volatile(
+      "subs %1, %1, %2;\n"
+      "bvs 1f;\n"
+      "mov %0, $0;\n"
+      "str %1, [%3, #0]\n"
+      "1:"
+      : "+r"(res), "+r"(lhs)
+      : "r"(rhs), "r"(out)
+      : "cc", "r12");
+#else
+#error "Unsupported platform"
+#endif
+  return res;
+}
+
+
+DART_FORCE_INLINE static int32_t SignedMulWithOverflow(int32_t lhs, int32_t rhs,
+                                                       intptr_t* out) {
+  int32_t res = 1;
+#if defined(HAS_MUL_OVERFLOW)
+  res = __builtin_smul_overflow(lhs, rhs, out);
+#elif defined(__i386__)
+  asm volatile(
+      "imul %2, %1\n"
+      "jo 1f;\n"
+      "xor %0, %0\n"
+      "mov %1, 0(%3)\n"
+      "1: "
+      : "+r"(res), "+r"(lhs)
+      : "r"(rhs), "r"(out)
+      : "cc");
+#elif defined(__arm__)
+  asm volatile(
+      "smull %1, ip, %1, %2;\n"
+      "cmp ip, %1, ASR #31;\n"
+      "bne 1f;\n"
+      "mov %0, $0;\n"
+      "str %1, [%3, #0]\n"
+      "1:"
+      : "+r"(res), "+r"(lhs)
+      : "r"(rhs), "r"(out)
+      : "cc", "r12");
+#else
+#error "Unsupported platform"
+#endif
+  return res;
+}
+
+DART_FORCE_INLINE static int32_t SMI_DIV(int32_t lhs, int32_t rhs,
+                                         intptr_t* out) {
+  if (rhs == 0) {
+    return 1;
+  }
+
+  const int32_t res = (lhs >> 1) / (rhs >> 1);
+  if (res == 0x40000000) {
+    return 1;  // Overflow
+  }
+
+  *out = res << 1;
+  return 0;
+}
+
+
+#define LIKELY(cond) __builtin_expect((cond), 1)
+
+
+DART_FORCE_INLINE static bool AreBothSmis(intptr_t a, intptr_t b) {
+  return ((a | b) & kHeapObjectTag) == 0;
+}
+
+
+#define SMI_MUL(lhs, rhs, pres) SignedMulWithOverflow((lhs), (rhs) >> 1, pres)
+#define SMI_COND(cond, lhs, rhs, pres) \
+  ((*(pres) = ((lhs cond rhs) ? true_value : false_value)), false)
+#define SMI_EQ(lhs, rhs, pres) SMI_COND(==, lhs, rhs, pres)
+#define SMI_LT(lhs, rhs, pres) SMI_COND(<, lhs, rhs, pres)
+#define SMI_GT(lhs, rhs, pres) SMI_COND(>, lhs, rhs, pres)
+#define SMI_BITOR(lhs, rhs, pres) ((*(pres) = (lhs | rhs)), false)
+#define SMI_BITAND(lhs, rhs, pres) ((*(pres) = (lhs & rhs)), false)
+
+
+void Simulator::CallRuntime(Thread* thread, RawObject** base,
+                            RawObject** exit_frame, uint32_t* pc,
+                            intptr_t argc_tag, RawObject** args,
+                            RawObject** result, uword target) {
+  Exit(thread, base, exit_frame, pc);
+  NativeArguments native_args(thread, argc_tag, args, result);
+  reinterpret_cast<RuntimeFunction>(target)(native_args);
+}
+
+
+DART_FORCE_INLINE void Simulator::Invoke(Thread* thread, RawObject** call_base,
+                                         RawObject** call_top,
+                                         RawObjectPool** pp, uint32_t** pc,
+                                         RawObject*** B, RawObject*** SP) {
+  RawObject** callee_fp = call_top + kDartFrameFixedSize;
+
+  RawFunction* function = FrameFunction(callee_fp);
+  RawCode* code = function->ptr()->code_;
+  callee_fp[kPcMarkerSlotFromFp] = code;
+  callee_fp[kSavedCallerPcSlotFromFp] = reinterpret_cast<RawObject*>(*pc);
+  callee_fp[kSavedCallerFpSlotFromFp] = reinterpret_cast<RawObject*>(*B);
+  *pp = code->ptr()->object_pool_->ptr();
+  *pc = reinterpret_cast<uint32_t*>(code->ptr()->entry_point_);
+  *B = callee_fp;
+  *SP = *B - 1;
+}
+
+
+void Simulator::InlineCacheMiss(int checked_args, Thread* thread,
+                                RawICData* icdata, RawObject** call_base,
+                                RawObject** top, uint32_t* pc, RawObject** B,
+                                RawObject** SP) {
+  RawObject** args = call_base;
+  for (intptr_t i = 0; i < checked_args; i++) {
+    top[1 + i] = args[i];
+  }
+  top[1 + checked_args] = icdata;
+  RuntimeFunction handler = NULL;
+  switch (checked_args) {
+    case 1:
+      handler = DRT_InlineCacheMissHandlerOneArg;
+      break;
+    case 2:
+      handler = DRT_InlineCacheMissHandlerTwoArgs;
+      break;
+    case 3:
+      handler = DRT_InlineCacheMissHandlerThreeArgs;
+      break;
+    default:
+      UNREACHABLE();
+      break;
+  }
+  CallRuntime(thread, B, top + checked_args + 1 + 1, pc, checked_args + 1,
+              top + 1, top, reinterpret_cast<uword>(handler));
+}
+
+
+DART_FORCE_INLINE void Simulator::InstanceCall1(
+    Thread* thread, RawICData* icdata, RawObject** call_base, RawObject** top,
+    Array* argdesc, RawObjectPool** pp, uint32_t** pc, RawObject*** B,
+    RawObject*** SP) {
+  ASSERT(icdata->GetClassId() == kICDataCid);
+  SimulatorHelpers::IncrementUsageCounter(icdata);
+
+  const intptr_t kCheckedArgs = 1;
+  RawObject** args = call_base;
+  RawArray* cache = icdata->ptr()->ic_data_->ptr();
+
+  RawSmi* receiver_cid = SimulatorHelpers::GetClassIdAsSmi(args[0]);
+
+  bool found = false;
+  for (intptr_t i = 0, length = Smi::Value(cache->length_);
+       i < (length - (kCheckedArgs + 2)); i += (kCheckedArgs + 2)) {
+    if (cache->data()[i + 0] == receiver_cid) {
+      top[0] = cache->data()[i + kCheckedArgs];
+      found = true;
+      break;
+    }
+  }
+
+  if (!found) {
+    InlineCacheMiss(kCheckedArgs, thread, icdata, call_base, top, *pc, *B, *SP);
+  }
+
+  *argdesc = icdata->ptr()->args_descriptor_;
+  Invoke(thread, call_base, top, pp, pc, B, SP);
+}
+
+
+DART_FORCE_INLINE void Simulator::InstanceCall2(
+    Thread* thread, RawICData* icdata, RawObject** call_base, RawObject** top,
+    Array* argdesc, RawObjectPool** pp, uint32_t** pc, RawObject*** B,
+    RawObject*** SP) {
+  ASSERT(icdata->GetClassId() == kICDataCid);
+  SimulatorHelpers::IncrementUsageCounter(icdata);
+
+  const intptr_t kCheckedArgs = 2;
+  RawObject** args = call_base;
+  RawArray* cache = icdata->ptr()->ic_data_->ptr();
+
+  RawSmi* receiver_cid = SimulatorHelpers::GetClassIdAsSmi(args[0]);
+  RawSmi* arg0_cid = SimulatorHelpers::GetClassIdAsSmi(args[1]);
+
+  bool found = false;
+  for (intptr_t i = 0, length = Smi::Value(cache->length_);
+       i < (length - (kCheckedArgs + 2)); i += (kCheckedArgs + 2)) {
+    if (cache->data()[i + 0] == receiver_cid &&
+        cache->data()[i + 1] == arg0_cid) {
+      top[0] = cache->data()[i + kCheckedArgs];
+      found = true;
+      break;
+    }
+  }
+
+  if (!found) {
+    InlineCacheMiss(kCheckedArgs, thread, icdata, call_base, top, *pc, *B, *SP);
+  }
+
+  *argdesc = icdata->ptr()->args_descriptor_;
+  Invoke(thread, call_base, top, pp, pc, B, SP);
+}
+
+
+DART_FORCE_INLINE void Simulator::InstanceCall3(
+    Thread* thread, RawICData* icdata, RawObject** call_base, RawObject** top,
+    Array* argdesc, RawObjectPool** pp, uint32_t** pc, RawObject*** B,
+    RawObject*** SP) {
+  ASSERT(icdata->GetClassId() == kICDataCid);
+  SimulatorHelpers::IncrementUsageCounter(icdata);
+
+  const intptr_t kCheckedArgs = 3;
+  RawObject** args = call_base;
+  RawArray* cache = icdata->ptr()->ic_data_->ptr();
+
+  RawSmi* receiver_cid = SimulatorHelpers::GetClassIdAsSmi(args[0]);
+  RawSmi* arg0_cid = SimulatorHelpers::GetClassIdAsSmi(args[1]);
+  RawSmi* arg1_cid = SimulatorHelpers::GetClassIdAsSmi(args[2]);
+
+  bool found = false;
+  for (intptr_t i = 0, length = Smi::Value(cache->length_);
+       i < (length - (kCheckedArgs + 2)); i += (kCheckedArgs + 2)) {
+    if (cache->data()[i + 0] == receiver_cid &&
+        cache->data()[i + 1] == arg0_cid && cache->data()[i + 2] == arg1_cid) {
+      top[0] = cache->data()[i + kCheckedArgs];
+      found = true;
+      break;
+    }
+  }
+
+  if (!found) {
+    InlineCacheMiss(kCheckedArgs, thread, icdata, call_base, top, *pc, *B, *SP);
+  }
+
+  *argdesc = icdata->ptr()->args_descriptor_;
+  Invoke(thread, call_base, top, pp, pc, B, SP);
+}
+
+
+static __attribute__((noinline)) bool InvokeRuntime(
+    Thread* thread, Simulator* sim, RuntimeFunction drt,
+    const NativeArguments& args) {
+  SimulatorSetjmpBuffer buffer(sim);
+  if (!setjmp(buffer.buffer_)) {
+    thread->set_vm_tag(reinterpret_cast<uword>(drt));
+    drt(args);
+    thread->set_vm_tag(VMTag::kDartTagId);
+    return true;
+  } else {
+    return false;
+  }
+}
+
+
+static __attribute__((noinline)) bool InvokeNative(
+    Thread* thread, Simulator* sim, SimulatorBootstrapNativeCall f,
+    NativeArguments* args) {
+  SimulatorSetjmpBuffer buffer(sim);
+  if (!setjmp(buffer.buffer_)) {
+    thread->set_vm_tag(reinterpret_cast<uword>(f));
+    f(args);
+    thread->set_vm_tag(VMTag::kDartTagId);
+    return true;
+  } else {
+    return false;
+  }
+}
+
+
+static __attribute__((noinline)) bool InvokeNativeWrapper(
+    Thread* thread, Simulator* sim, Dart_NativeFunction f,
+    NativeArguments* args) {
+  SimulatorSetjmpBuffer buffer(sim);
+  if (!setjmp(buffer.buffer_)) {
+    thread->set_vm_tag(reinterpret_cast<uword>(f));
+    NativeEntry::NativeCallWrapper(
+        reinterpret_cast<Dart_NativeArguments>(args), f);
+    thread->set_vm_tag(VMTag::kDartTagId);
+    return true;
+  } else {
+    return false;
+  }
+}
+
+
+RawObject* Simulator::Call(const Code& code, const Array& arguments_descriptor,
+                           const Array& arguments, Thread* thread) {
+  static const void* dispatch[] = {
+#define TARGET(name, fmt, fmta, fmtb, fmtc) &&bc##name,
+    BYTECODES_LIST(TARGET)
+#undef TARGET
+  };
+
+  const uword vm_tag = thread->vm_tag();
+  thread->set_vm_tag(VMTag::kDartTagId);
+
+  StackResource* top_resource = thread->top_resource();
+  thread->set_top_resource(NULL);
+
+  if (top_ == NULL) {
+    top_ = base_ = stack_;
+  }
+
+  top_[0] = thread->top_exit_frame_info();
+
+  // Unpack arguments.
+  {
+    const intptr_t argc = arguments.Length();
+    RawObject** call_base = reinterpret_cast<RawObject**>(top_ + 1);
+    RawObject** call_top = call_base + argc;
+    for (intptr_t i = 0; i < argc; i++) {
+      call_base[i] = arguments.At(i);
+    }
+
+    call_top[0] = code.function();
+    call_top[1] = code.raw();
+    call_top[2] =
+        reinterpret_cast<RawObject*>((argc << 2) | 2);  // Return address.
+    call_top[3] = reinterpret_cast<RawObject*>(top_);   // Caller FP
+  }
+
+  RawObject** B =
+      reinterpret_cast<RawObject**>(top_ +
+                                    arguments.Length() +
+                                    kDartFrameFixedSize +
+                                    1);
+  RawObject** SP = B - 1;
+  uint32_t* pc = reinterpret_cast<uint32_t*>(code.raw()->ptr()->entry_point_);
+  RawObjectPool* pp = code.object_pool();
+
+  pp = pp->ptr();
+  RawBool* true_value = Bool::True().raw();
+  RawBool* false_value = Bool::False().raw();
+  RawObject* null_value = Object::null();
+  RawObject* empty_context = thread->isolate()->object_store()->empty_context();
+
+  Array& argdesc = Array::Handle();
+#if defined(DEBUG)
+  Function& function_h = Function::Handle();
+#endif
+  argdesc = arguments_descriptor.raw();
+
+#define DECLARE_A_B_C \
+  uint16_t rB, rC;    \
+  USE(rB);            \
+  USE(rC)
+#define DECODE_A_B_C(type, shiftB, shiftC, mask) \
+  rB = ((__op >> shiftB) & mask) /* | rBx */;    \
+  rC = ((__op >> shiftC) & mask) /* | rCx */;
+
+#define DECLARE_0
+#define DECODE_0(type, shiftB, shiftC, mask)
+
+#define DECLARE_A
+#define DECODE_A(type, shiftB, shiftC, mask)
+
+#define DECLARE_A_D \
+  uint32_t rD;      \
+  USE(rD)
+#define DECODE_A_D(type, shiftB, shiftC, mask) rD = (__op >> shiftB);
+
+#define DECLARE___D \
+  uint32_t rD;      \
+  USE(rD)
+#define DECODE___D(type, shiftB, shiftC, mask) rD = (__op >> shiftB);
+
+#define DECLARE_A_X \
+  int32_t rD;       \
+  USE(rD)
+#define DECODE_A_X(type, shiftB, shiftC, mask) \
+  rD = (static_cast<int32_t>(__op) >> shiftB);
+
+#define BYTECODE_HEADER(Name, Declare, Decode) \
+  Declare;                                     \
+  bc##Name : Decode(uint8_t, 16, 24, 0xFF);    \
+  goto bc##Name##Entry;                        \
+  bc##Name##Entry:
+
+#define BYTECODE(Name, type) \
+  BYTECODE_HEADER(Name, DECLARE_##type, DECODE_##type)
+
+#define DISPATCH_OP(val)         \
+  do {                           \
+    __op = (val);                \
+    rA = ((__op >> 8) & 0xFF);   \
+    goto* dispatch[__op & 0xFF]; \
+  } while (0)
+
+#define DISPATCH() DISPATCH_OP(*pc++)
+
+#define SMI_FASTPATH_TOS(ResultT, F)                           \
+  {                                                            \
+    const intptr_t lhs = reinterpret_cast<intptr_t>(SP[-1]);   \
+    const intptr_t rhs = reinterpret_cast<intptr_t>(SP[-0]);   \
+    ResultT* slot = reinterpret_cast<ResultT*>(SP - 1);        \
+    if (LIKELY(AreBothSmis(lhs, rhs) && !F(lhs, rhs, slot))) { \
+      pc += 1;                                                 \
+      --SP;                                                    \
+    }                                                          \
+    DISPATCH();                                                \
+  }
+
+#define FALLTHROUGH
+
+#define HANDLE_EXCEPTION(name, ON_EXCEPTION)                                   \
+  do {                                                                         \
+    B = reinterpret_cast<RawObject**>(base_);                                  \
+    pc = reinterpret_cast<uint32_t*>(pc_);                                     \
+    if ((reinterpret_cast<uword>(pc) & 2) != 0) {                              \
+      base_ = top_ = reinterpret_cast<uintptr_t*>(base_[0]);                   \
+      thread->set_top_exit_frame_info(reinterpret_cast<uword>(top_));          \
+      thread->set_top_resource(top_resource);                                  \
+      thread->set_vm_tag(vm_tag);                                              \
+      return special_[0];                                                      \
+    }                                                                          \
+    pp = FrameCode(B)->ptr()->object_pool_->ptr();                             \
+    ON_EXCEPTION;                                                              \
+  } while (0)
+
+#define INVOKE_RUNTIME(func, args, onexception)   \
+  if (!InvokeRuntime(thread, this, func, args)) { \
+    HANDLE_EXCEPTION(InvokeRuntime, onexception); \
+  }
+
+#define INVOKE_NATIVE(func, args, onexception)     \
+  if (!InvokeNative(thread, this, func, &args)) {  \
+    HANDLE_EXCEPTION(InvokeRuntime, onexception);  \
+  }
+
+#define INVOKE_NATIVE_WRAPPER(func, args, onexception)   \
+  if (!InvokeNativeWrapper(thread, this, func, &args)) { \
+    HANDLE_EXCEPTION(InvokeRuntime, onexception);        \
+  }
+
+  uint16_t rA;
+  uint32_t __op;
+  DISPATCH();
+  while (true) {
+    {
+      {
+      ClosureNoSuchMethod:
+#if defined(DEBUG)
+        function_h ^= FrameFunction(B);
+        ASSERT(function_h.IsClosureFunction());
+#endif
+        pc = SavedCallerPC(B);
+
+        const bool has_dart_callee = (reinterpret_cast<uword>(pc) & 2) == 0;
+        const intptr_t argc = has_dart_callee
+                                  ? Bytecode::DecodeArgc(pc[-1])
+                                  : (reinterpret_cast<uword>(pc) >> 2);
+
+        SP = FrameArguments(B, 0);
+        RawObject** args = SP - argc;
+        B = SavedCallerFP(B);
+        if (has_dart_callee) {
+          pp = FrameCode(B)->ptr()->object_pool_->ptr();
+        }
+
+        *++SP = null_value;
+        *++SP = args[0];
+        *++SP = argdesc.raw();
+        *++SP = null_value;  // will contain array
+        {
+          SP[1] = Smi::New(argc);  // length
+          SP[2] = null_value;      // type
+          Exit(thread, B, SP + 3, pc);
+          NativeArguments native_args(thread, 2, SP + 1, SP);
+          INVOKE_RUNTIME(DRT_AllocateArray, native_args,
+                         goto ClosureNoSuchMethodDispatch);
+
+          RawArray* array = static_cast<RawArray*>(SP[0]);
+          ASSERT(array->GetClassId() == kArrayCid);
+          for (intptr_t i = 0; i < argc; i++) {
+            array->ptr()->data()[i] = args[i];
+          }
+        }
+        {
+          Exit(thread, B, SP + 1, pc);
+          NativeArguments native_args(thread, 3, SP - 2, SP - 3);
+          INVOKE_RUNTIME(DRT_InvokeClosureNoSuchMethod, native_args,
+                         goto ClosureNoSuchMethodDispatch);
+          UNREACHABLE();
+        }
+      ClosureNoSuchMethodDispatch:
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(Entry, A_B_C);
+        const uint16_t num_locals = rB;
+        const uint16_t context_reg = rC;
+        const intptr_t pos_count = Smi::Value(
+            *reinterpret_cast<RawSmi**>(
+                reinterpret_cast<uword>(argdesc.raw()->ptr()) +
+                Array::element_offset(
+                    ArgumentsDescriptor::kPositionalCountIndex)));
+
+        if (pos_count != rA) {
+          goto ClosureNoSuchMethod;
+        }
+
+        {
+          RawObject** L = B;
+          for (intptr_t i = 0; i < num_locals; i++) {
+            L[i] = null_value;
+          }
+          L[context_reg] = empty_context;
+          SP = B + num_locals - 1;
+        }
+
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(DebugStep, A);
+        if (thread->isolate()->single_step()) {
+          Exit(thread, B, SP + 1, pc);
+          NativeArguments args(thread, 0, NULL, NULL);
+          INVOKE_RUNTIME(DRT_SingleStepHandler, args, FALLTHROUGH);
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(DebugBreak, A);
+        {
+          const uint32_t original_bc =
+              static_cast<uint32_t>(reinterpret_cast<uintptr_t>(
+                  thread->isolate()->debugger()->GetPatchedStubAddress(
+                      reinterpret_cast<uword>(pc))));
+
+          SP[1] = null_value;
+          Exit(thread, B, SP + 2, pc);
+          NativeArguments args(thread, 0, NULL, SP + 1);
+          INVOKE_RUNTIME(DRT_BreakpointRuntimeHandler, args, FALLTHROUGH) else {
+            DISPATCH_OP(original_bc);
+          }
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(CheckStack, A);
+        {
+          if (reinterpret_cast<uword>(SP) >= thread->isolate()->stack_limit()) {
+            Exit(thread, B, SP + 1, pc);
+            NativeArguments args(thread, 0, NULL, NULL);
+            INVOKE_RUNTIME(DRT_StackOverflow, args, FALLTHROUGH);
+          }
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(EntryOpt, A_B_C);
+        const uint16_t num_fixed_params = rA;
+        const uint16_t num_opt_pos_params = rB;
+        const uint16_t num_opt_named_params = rC;
+
+        const intptr_t min_num_pos_args = num_fixed_params;
+        const intptr_t max_num_pos_args = num_fixed_params + num_opt_pos_params;
+        const intptr_t arg_count = Smi::Value(*reinterpret_cast<RawSmi**>(
+            reinterpret_cast<uword>(argdesc.raw()->ptr()) +
+            Array::element_offset(ArgumentsDescriptor::kCountIndex)));
+        const intptr_t pos_count = Smi::Value(*reinterpret_cast<RawSmi**>(
+            reinterpret_cast<uword>(argdesc.raw()->ptr()) +
+            Array::element_offset(ArgumentsDescriptor::kPositionalCountIndex)));
+        const intptr_t named_count = (arg_count - pos_count);
+        if (!(min_num_pos_args <= pos_count && pos_count <= max_num_pos_args)) {
+          goto ClosureNoSuchMethod;
+        }
+
+        // Copy all passed position arguments.Entry
+        RawObject** first_arg = FrameArguments(B, arg_count);
+        memmove(B, first_arg, pos_count * kWordSize);
+        if (num_opt_named_params != 0) {
+          // RawObject** opt_copy = first_arg + pos_count;
+
+          intptr_t i = named_count - 1;
+          intptr_t j = num_opt_named_params - 1;
+          while (j >= 0 && i >= 0) {
+            const uint32_t load_name = pc[2 * j];
+            const uint32_t load_value = pc[2 * j + 1];
+            ASSERT((load_name & 0xFF) == Bytecode::kLoadConstant);
+            ASSERT((load_value & 0xFF) == Bytecode::kLoadConstant);
+            ASSERT((load_value & 0xFF00) == (load_name & 0xFF00));
+            const uint8_t reg = (load_name >> 8) & 0xFF;
+            RawString* name = reinterpret_cast<RawString*>(
+                pp->data()[load_name >> 16].raw_obj_);
+            if (name == argdesc.At(ArgumentsDescriptor::name_index(i))) {
+              const intptr_t copy_idx = Smi::Value(static_cast<RawSmi*>(
+                  argdesc.At(ArgumentsDescriptor::position_index(i))));
+              B[reg] = first_arg[copy_idx];
+              i--;
+            } else {
+              RawObject* value = pp->data()[load_value >> 16].raw_obj_;
+              B[reg] = value;
+            }
+            j--;
+          }
+
+          while (j >= 0) {
+            const uint32_t load_name = pc[2 * j];
+            const uint32_t load_value = pc[2 * j + 1];
+            ASSERT((load_name & 0xFF) == Bytecode::kLoadConstant);
+            ASSERT((load_value & 0xFF) == Bytecode::kLoadConstant);
+            ASSERT((load_value & 0xFF00) == (load_name & 0xFF00));
+            const uint8_t reg = (load_name >> 8) & 0xFF;
+            RawObject* value = pp->data()[load_value >> 16].raw_obj_;
+            B[reg] = value;
+            j--;
+          }
+
+          if (i != -1) {
+            goto ClosureNoSuchMethod;
+          }
+
+          pc += num_opt_named_params * 2;
+          SP = B + num_fixed_params + num_opt_named_params - 1;
+        } else {
+          ASSERT(num_opt_pos_params != 0);
+          if (named_count != 0) {
+            goto ClosureNoSuchMethod;
+          }
+
+          RawObject** opt_base = B + rA;
+          for (intptr_t i = pos_count - rA; i < num_opt_pos_params; i++) {
+            const uint32_t load_value = pc[i];
+            ASSERT((load_value & 0xFF) == Bytecode::kLoadConstant);
+            const uint8_t reg = (load_value >> 8) & 0xFF;
+            RawObject* value = pp->data()[load_value >> 16].raw_obj_;
+            ASSERT((i + rA) == reg);
+            opt_base[i] = value;
+          }
+
+          pc += num_opt_pos_params;
+          SP = B + max_num_pos_args - 1;
+        }
+
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(InstantiateType, A_D);
+        RawObject* type = pp->data()[rD].raw_obj_;
+        SP[1] = type;
+        SP[2] = SP[0];
+        SP[0] = null_value;
+        Exit(thread, B, SP + 3, pc);
+        {
+          NativeArguments args(thread, 2, SP + 1, SP);
+          INVOKE_RUNTIME(DRT_InstantiateType, args, FALLTHROUGH);
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(InstantiateTypeArgumentsTOS, A_D);
+        RawTypeArguments* type_arguments =
+            static_cast<RawTypeArguments*>(pp->data()[rD].raw_obj_);
+
+        RawObject* instantiator = SP[0];
+        // If the instantiator is null and if the type argument vector
+        // instantiated from null becomes a vector of dynamic, then use null as
+        // the type arguments.
+        if (rA == 0 || null_value != instantiator) {
+          RawArray* instantiations = type_arguments->ptr()->instantiations_;
+          for (intptr_t i = 0;
+               instantiations->ptr()->data()[i] != NULL;  // kNoInstantiator
+               i += 2) {
+            if (instantiations->ptr()->data()[i] == instantiator) {
+              SP[0] = instantiations->ptr()->data()[i + 1];
+              goto InstantiateTypeArgumentsTOSDone;
+            }
+          }
+
+          SP[1] = type_arguments;
+          SP[2] = instantiator;
+
+          Exit(thread, B, SP + 3, pc);
+          NativeArguments args(thread, 2, SP + 1, SP);
+          INVOKE_RUNTIME(DRT_InstantiateTypeArguments, args, FALLTHROUGH);
+        }
+
+      InstantiateTypeArgumentsTOSDone:
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(Throw, A);
+        {
+          SP[1] = 0;
+          Exit(thread, B, SP + 2, pc);
+          if (rA == 0) {
+            NativeArguments args(thread, 1, SP, SP + 1);
+            INVOKE_RUNTIME(DRT_Throw, args, FALLTHROUGH);
+          } else {
+            NativeArguments args(thread, 2, SP - 1, SP + 1);
+            INVOKE_RUNTIME(DRT_ReThrow, args, FALLTHROUGH);
+          }
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(Frame, A_D);
+        const uint16_t num_locals = rD;
+        for (intptr_t i = 1; i <= num_locals; i++) {
+          SP[i] = null_value;
+        }
+        SP += num_locals;
+
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(SetFrame, A);
+        SP = B + rA - 1;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(Drop1, 0);
+        SP--;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(Drop, 0);
+        SP -= rA;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(DropR, 0);
+        RawObject* result = SP[0];
+        SP -= rA;
+        SP[0] = result;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(LoadConstant, A_D);
+        B[rA] = pp->data()[rD].raw_obj_;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(PushConstant, __D);
+        *++SP = pp->data()[rD].raw_obj_;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(Push, A_X);
+        *++SP = B[rD];
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(Move, A_X);
+        B[rA] = B[rD];
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(StoreLocal, A_X);
+        B[rD] = *SP;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(PopLocal, A_X);
+        B[rD] = *SP--;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(MoveSpecial, A_D);
+        B[rA] = special_[rD];
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(BooleanNegateTOS, 0);
+        SP[0] = (SP[0] == true_value) ? false_value : true_value;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(StaticCall, A_D);
+        if (thread->isolate()->single_step()) {
+          Exit(thread, B, SP + 1, pc);
+          NativeArguments args(thread, 0, NULL, NULL);
+          INVOKE_RUNTIME(DRT_SingleStepHandler, args, goto StaticCallDispatch);
+        }
+
+        {
+          const uint16_t argc = rA;
+          RawObject** call_base = SP - argc;
+          RawObject** call_top = SP;  // *SP contains function
+          argdesc ^= pp->data()[rD].raw_obj_;
+          Invoke(thread, call_base, call_top, &pp, &pc, &B, &SP);
+        }
+
+      StaticCallDispatch:
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(InstanceCall, A_D);
+        if (thread->isolate()->single_step()) {
+          Exit(thread, B, SP + 1, pc);
+          NativeArguments args(thread, 0, NULL, NULL);
+          INVOKE_RUNTIME(DRT_SingleStepHandler, args,
+                         goto InstanceCallDispatch);
+        }
+
+        {
+          const uint16_t argc = rA;
+          const uint16_t kidx = rD;
+
+          RawObject** call_base = SP - argc + 1;
+          RawObject** call_top = SP + 1;
+          InstanceCall1(thread,
+                        static_cast<RawICData*>(pp->data()[kidx].raw_obj_),
+                        call_base, call_top, &argdesc, &pp, &pc, &B, &SP);
+        }
+
+      InstanceCallDispatch:
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(InstanceCall2, A_D);
+        if (thread->isolate()->single_step()) {
+          Exit(thread, B, SP + 1, pc);
+          NativeArguments args(thread, 0, NULL, NULL);
+          INVOKE_RUNTIME(DRT_SingleStepHandler, args,
+                         goto InstanceCall2Dispatch);
+        }
+
+        {
+          const uint16_t argc = rA;
+          const uint16_t kidx = rD;
+
+          RawObject** call_base = SP - argc + 1;
+          RawObject** call_top = SP + 1;
+          InstanceCall2(thread,
+                        static_cast<RawICData*>(pp->data()[kidx].raw_obj_),
+                        call_base, call_top, &argdesc, &pp, &pc, &B, &SP);
+        }
+
+      InstanceCall2Dispatch:
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(InstanceCall3, A_D);
+        if (thread->isolate()->single_step()) {
+          Exit(thread, B, SP + 1, pc);
+          NativeArguments args(thread, 0, NULL, NULL);
+          INVOKE_RUNTIME(DRT_SingleStepHandler, args,
+                         goto InstanceCall3Dispatch);
+        }
+
+        {
+          const uint16_t argc = rA;
+          const uint16_t kidx = rD;
+
+          RawObject** call_base = SP - argc + 1;
+          RawObject** call_top = SP + 1;
+          InstanceCall3(thread,
+                        static_cast<RawICData*>(pp->data()[kidx].raw_obj_),
+                        call_base, call_top, &argdesc, &pp, &pc, &B, &SP);
+        }
+
+      InstanceCall3Dispatch:
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(NativeBootstrapCall, 0);
+        RawFunction* function = FrameFunction(B);
+        RawObject** incoming_args =
+            function->ptr()->num_optional_parameters_ == 0
+                ? FrameArguments(B, function->ptr()->num_fixed_parameters_)
+                : B;
+
+        SimulatorBootstrapNativeCall native_target =
+            reinterpret_cast<SimulatorBootstrapNativeCall>(SP[-1]);
+        intptr_t argc_tag = reinterpret_cast<intptr_t>(SP[-0]);
+        SP[-0] = 0;  // Note: argc_tag is not smi-tagged.
+        SP[-1] = null_value;
+        Exit(thread, B, SP + 1, pc);
+        NativeArguments args(thread, argc_tag, incoming_args, SP - 1);
+        INVOKE_NATIVE(native_target, args, FALLTHROUGH) else { SP -= 1; }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(NativeCall, 0);
+        RawFunction* function = FrameFunction(B);
+        RawObject** incoming_args =
+            function->ptr()->num_optional_parameters_ == 0
+                ? FrameArguments(B, function->ptr()->num_fixed_parameters_)
+                : B;
+
+        Dart_NativeFunction native_target =
+            reinterpret_cast<Dart_NativeFunction>(SP[-1]);
+        intptr_t argc_tag = reinterpret_cast<intptr_t>(SP[-0]);
+        SP[-0] = 0;  // argc_tag is not smi tagged!
+        SP[-1] = null_value;
+        Exit(thread, B, SP + 1, pc);
+        NativeArguments args(thread, argc_tag, incoming_args, SP - 1);
+        INVOKE_NATIVE_WRAPPER(native_target, args, FALLTHROUGH) else {
+          SP -= 1;
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(AddTOS, A_B_C);
+        SMI_FASTPATH_TOS(intptr_t, SignedAddWithOverflow);
+      }
+      {
+        BYTECODE(SubTOS, A_B_C);
+        SMI_FASTPATH_TOS(intptr_t, SignedSubWithOverflow);
+      }
+      {
+        BYTECODE(MulTOS, A_B_C);
+        SMI_FASTPATH_TOS(intptr_t, SMI_MUL);
+      }
+      {
+        BYTECODE(BitOrTOS, A_B_C);
+        SMI_FASTPATH_TOS(intptr_t, SMI_BITOR);
+      }
+      {
+        BYTECODE(BitAndTOS, A_B_C);
+        SMI_FASTPATH_TOS(intptr_t, SMI_BITAND);
+      }
+      {
+        BYTECODE(EqualTOS, A_B_C);
+        SMI_FASTPATH_TOS(RawObject*, SMI_EQ);
+      }
+      {
+        BYTECODE(LessThanTOS, A_B_C);
+        SMI_FASTPATH_TOS(RawObject*, SMI_LT);
+      }
+      {
+        BYTECODE(GreaterThanTOS, A_B_C);
+        SMI_FASTPATH_TOS(RawObject*, SMI_GT);
+      }
+
+      {
+        BYTECODE(Compile, 0);
+        B[0] = FrameFunction(B);
+        B[1] = 0;
+        Exit(thread, B, B + 2, pc);
+        NativeArguments args(thread, 1, B, B + 1);
+        INVOKE_RUNTIME(DRT_CompileFunction, args, FALLTHROUGH) else {
+          // Function should be compiled now.
+          RawCode* code = FrameFunction(B)->ptr()->code_;
+          SetFrameCode(B, code);
+          pp = code->ptr()->object_pool_->ptr();
+          pc = reinterpret_cast<uint32_t*>(code->ptr()->entry_point_);
+        }
+        DISPATCH();
+      }
+
+      {
+        RawObject* result;
+
+        BYTECODE(Intrinsic, A);
+        result = null_value;
+        if (!intrinsics_[rA](thread, B, &result)) {
+          DISPATCH();
+        }
+        goto ReturnImpl;
+
+        BYTECODE(Return, A);
+        result = B[rA];
+        goto ReturnImpl;
+
+        BYTECODE(ReturnTOS, 0);
+        result = *SP;
+
+      ReturnImpl:
+        pc = SavedCallerPC(B);
+        if ((reinterpret_cast<uword>(pc) & 2) != 0) {
+          const intptr_t argc = reinterpret_cast<uword>(pc) >> 2;
+          base_ = top_ = reinterpret_cast<uintptr_t*>(
+              FrameArguments(B, argc + 1)[0]);
+          thread->set_top_exit_frame_info(reinterpret_cast<uword>(top_));
+          thread->set_top_resource(top_resource);
+          thread->set_vm_tag(vm_tag);
+          return result;
+        }
+        const uint8_t argc = Bytecode::DecodeArgc(pc[-1]);
+        SP = FrameArguments(B, argc);
+        B = SavedCallerFP(B);
+        *SP = result;
+        RawCode* code = FrameCode(B);
+        pp = code->ptr()->object_pool_->ptr();
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(StoreStaticTOS, A_D);
+        RawField* field = reinterpret_cast<RawField*>(pp->data()[rD].raw_obj_);
+        RawInstance* value = static_cast<RawInstance*>(*SP--);
+        field->StorePointer(&field->ptr()->value_.static_value_, value);
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(PushStatic, A_D);
+        RawField* field = reinterpret_cast<RawField*>(pp->data()[rD].raw_obj_);
+        *SP = field->ptr()->value_.static_value_;  // Note: field on the stack.
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(StoreField, A_B_C);
+        const uint16_t offset_in_words = rB;
+        const uint16_t value_reg = rC;
+
+        RawInstance* instance = reinterpret_cast<RawInstance*>(B[rA]);
+        RawObject* value = reinterpret_cast<RawObject*>(B[value_reg]);
+
+        instance->StorePointer(
+            reinterpret_cast<RawObject**>(instance->ptr()) + offset_in_words,
+            value);
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(StoreFieldTOS, A_D);
+        const uint16_t offset_in_words = rD;
+        RawInstance* instance = reinterpret_cast<RawInstance*>(SP[-1]);
+        RawObject* value = reinterpret_cast<RawObject*>(SP[0]);
+        SP -= 2;
+        instance->StorePointer(
+            reinterpret_cast<RawObject**>(instance->ptr()) + offset_in_words,
+            value);
+
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(LoadField, A_B_C);
+        const uint16_t instance_reg = rB;
+        const uint16_t offset_in_words = rC;
+        RawInstance* instance = reinterpret_cast<RawInstance*>(B[instance_reg]);
+        B[rA] = reinterpret_cast<RawObject**>(instance->ptr())[offset_in_words];
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(LoadFieldTOS, A_D);
+        const uint16_t offset_in_words = rD;
+        RawInstance* instance = static_cast<RawInstance*>(SP[0]);
+        SP[0] = reinterpret_cast<RawObject**>(instance->ptr())[offset_in_words];
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(InitStaticTOS, A);
+        RawField* field = static_cast<RawField*>(*SP--);
+        RawObject* value = field->ptr()->value_.static_value_;
+        if ((value == Object::sentinel().raw()) ||
+            (value == Object::transition_sentinel().raw())) {
+          /* SP[1] field */
+          SP[2] = 0;
+          Exit(thread, B, SP + 3, pc);
+          NativeArguments args(thread, 1, SP + 1, SP + 2);
+          INVOKE_RUNTIME(DRT_InitStaticField, args, FALLTHROUGH);
+        }
+        DISPATCH();
+      }
+
+      // TODO(vegorov) allocation bytecodes can benefit from the new-space
+      // allocation fast-path that does not transition into the runtime system.
+      {
+        BYTECODE(AllocateContext, A_D);
+        const uint16_t num_context_variables = rD;
+        {
+          *++SP = 0;
+          SP[1] = Smi::New(num_context_variables);
+          Exit(thread, B, SP + 2, pc);
+          NativeArguments args(thread, 1, SP + 1, SP);
+          INVOKE_RUNTIME(DRT_AllocateContext, args, FALLTHROUGH);
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(CloneContext, A);
+        {
+          SP[1] = SP[0];
+          Exit(thread, B, SP + 2, pc);
+          NativeArguments args(thread, 1, SP + 1, SP);
+          INVOKE_RUNTIME(DRT_CloneContext, args, FALLTHROUGH);
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(Allocate, A_D);
+        SP[1] = 0;  // result
+        SP[2] = pp->data()[rD].raw_obj_;
+        SP[3] = null_value;
+        Exit(thread, B, SP + 4, pc);
+        NativeArguments args(thread, 2, SP + 2, SP + 1);
+        INVOKE_RUNTIME(DRT_AllocateObject, args, FALLTHROUGH);
+        SP++;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(AllocateT, 0);
+        SP[1] = SP[-0];  // class
+        SP[2] = SP[-1];  // type arguments
+        Exit(thread, B, SP + 3, pc);
+        NativeArguments args(thread, 2, SP + 1, SP - 1);
+        INVOKE_RUNTIME(DRT_AllocateObject, args, FALLTHROUGH);
+        SP -= 1;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(CreateArrayTOS, 0);
+        SP[1] = SP[-0];  // length
+        SP[2] = SP[-1];  // type
+        Exit(thread, B, SP + 3, pc);
+        NativeArguments args(thread, 2, SP + 1, SP - 1);
+        INVOKE_RUNTIME(DRT_AllocateArray, args, FALLTHROUGH);
+        SP -= 1;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(AssertAssignable, A_D);  // instance, type args, type, name
+        RawObject** args = SP - 3;
+        if (args[0] != null_value) {
+          RawSubtypeTestCache* cache =
+              static_cast<RawSubtypeTestCache*>(pp->data()[rD].raw_obj_);
+          if (cache != null_value) {
+            RawInstance* instance = static_cast<RawInstance*>(args[0]);
+            RawTypeArguments* instantiator_type_arguments =
+                static_cast<RawTypeArguments*>(args[1]);
+
+            const intptr_t cid = SimulatorHelpers::GetClassId(instance);
+
+            RawTypeArguments* instance_type_arguments =
+                static_cast<RawTypeArguments*>(null_value);
+            RawObject* instance_cid_or_function;
+            if (cid == kClosureCid) {
+              RawClosure* closure = static_cast<RawClosure*>(instance);
+              instance_type_arguments = closure->ptr()->type_arguments_;
+              instance_cid_or_function = closure->ptr()->function_;
+            } else {
+              instance_cid_or_function = Smi::New(cid);
+
+              RawClass* instance_class =
+                  thread->isolate()->class_table()->At(cid);
+              if (instance_class->ptr()->num_type_arguments_ < 0) {
+                goto AssertAssignableCallRuntime;
+              } else if (instance_class->ptr()->num_type_arguments_ > 0) {
+                instance_type_arguments = reinterpret_cast<RawTypeArguments**>(
+                    instance
+                        ->ptr())[instance_class->ptr()
+                                     ->type_arguments_field_offset_in_words_];
+              }
+            }
+
+            for (RawObject** entries = cache->ptr()->cache_->ptr()->data();
+                 entries[0] != null_value;
+                 entries += SubtypeTestCache::kTestEntryLength) {
+              if (entries[SubtypeTestCache::kInstanceClassIdOrFunction] ==
+                      instance_cid_or_function &&
+                  entries[SubtypeTestCache::kInstanceTypeArguments] ==
+                      instance_type_arguments &&
+                  entries[SubtypeTestCache::kInstantiatorTypeArguments] ==
+                      instantiator_type_arguments) {
+                if (true_value == entries[SubtypeTestCache::kTestResult]) {
+                  goto AssertAssignableOk;
+                } else {
+                  break;
+                }
+              }
+            }
+          }
+
+        AssertAssignableCallRuntime:
+          SP[1] = args[0];  // instance
+          SP[2] = args[2];  // type
+          SP[3] = args[1];  // type args
+          SP[4] = args[3];  // name
+          SP[5] = cache;
+          Exit(thread, B, SP + 6, pc);
+          NativeArguments args(thread, 5, SP + 1, SP - 3);
+          INVOKE_RUNTIME(DRT_TypeCheck, args, FALLTHROUGH);
+        }
+
+      AssertAssignableOk:
+        SP -= 3;
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(AssertBoolean, A);
+        RawObject* value = SP[0];
+        if (rA) {
+          if (value == true_value || value == false_value) {
+            goto AssertBooleanOk;
+          }
+        } else if (value != null_value) {
+          goto AssertBooleanOk;
+        }
+
+        {
+          SP[1] = SP[0];  // instance
+          Exit(thread, B, SP + 2, pc);
+          NativeArguments args(thread, 1, SP + 1, SP);
+          INVOKE_RUNTIME(DRT_NonBoolTypeError, args, FALLTHROUGH);
+        }
+
+      AssertBooleanOk:
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(IfEqStrictTOS, A_D);
+        SP -= 2;
+        if (SP[1] != SP[2]) {
+          pc++;
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(IfNeStrictTOS, A_D);
+        SP -= 2;
+        if (SP[1] == SP[2]) {
+          pc++;
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(IfEqStrictNumTOS, A_D);
+        if (thread->isolate()->single_step()) {
+          Exit(thread, B, SP + 1, pc);
+          NativeArguments args(thread, 0, NULL, NULL);
+          INVOKE_RUNTIME(DRT_SingleStepHandler, args, FALLTHROUGH);
+        }
+
+        SP -= 2;
+        if (!SimulatorHelpers::IsStrictEqualWithNumberCheck(SP[1], SP[2])) {
+          pc++;
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(IfNeStrictNumTOS, A_D);
+        if (thread->isolate()->single_step()) {
+          Exit(thread, B, SP + 1, pc);
+          NativeArguments args(thread, 0, NULL, NULL);
+          INVOKE_RUNTIME(DRT_SingleStepHandler, args, FALLTHROUGH);
+        }
+
+        SP -= 2;
+        if (SimulatorHelpers::IsStrictEqualWithNumberCheck(SP[1], SP[2])) {
+          pc++;
+        }
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(Jump, 0);
+        const int32_t tgt = static_cast<int32_t>(__op) >> 8;
+        pc += (tgt - 1);
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(StoreIndexedTOS, 0);
+        SP -= 3;
+        RawArray* array = static_cast<RawArray*>(SP[1]);
+        RawSmi* index = static_cast<RawSmi*>(SP[2]);
+        RawObject* value = SP[3];
+        ASSERT(array->GetClassId() == kArrayCid);
+        ASSERT(!index->IsHeapObject());
+        array->StorePointer(array->ptr()->data() + Smi::Value(index), value);
+        DISPATCH();
+      }
+
+      {
+        BYTECODE(Trap, 0);
+        UNIMPLEMENTED();
+        DISPATCH();
+      }
+    }
+  }
+
+  UNREACHABLE();
+  return 0;
+}
+
+void Simulator::Longjmp(uword pc, uword sp, uword fp, RawObject* raw_exception,
+                        RawObject* raw_stacktrace, Thread* thread) {
+  // Walk over all setjmp buffers (simulated --> C++ transitions)
+  // and try to find the setjmp associated with the simulated stack pointer.
+  SimulatorSetjmpBuffer* buf = last_setjmp_buffer();
+  while ((buf->link() != NULL) && (buf->link()->base() > fp)) {
+    buf = buf->link();
+  }
+  ASSERT(buf != NULL);
+  ASSERT(last_setjmp_buffer() == buf);
+
+  // The C++ caller has not cleaned up the stack memory of C++ frames.
+  // Prepare for unwinding frames by destroying all the stack resources
+  // in the previous C++ frames.
+  StackResource::Unwind(thread);
+
+  // Set the tag.
+  thread->set_vm_tag(VMTag::kDartTagId);
+  // Clear top exit frame.
+  thread->set_top_exit_frame_info(0);
+
+  ASSERT(raw_exception != Object::null());
+  top_ = reinterpret_cast<uintptr_t*>(sp);
+  base_ = reinterpret_cast<uintptr_t*>(fp);
+  pc_ = pc;
+  special_[kExceptionSpecialIndex] = raw_exception;
+  special_[kStacktraceSpecialIndex] = raw_stacktrace;
+  buf->Longjmp();
+  UNREACHABLE();
+}
+
+}  // namespace dart
+
+
+#endif  // defined TARGET_ARCH_DBC