Initial SIMDBC interpreter.

runtime/vm/assembler_dbc.h

+// 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.
+
+#ifndef VM_ASSEMBLER_DBC_H_
+#define VM_ASSEMBLER_DBC_H_
+
+#ifndef VM_ASSEMBLER_H_
+#error Do not include assembler_dbc.h directly; use assembler.h instead.
+#endif
+
+#include "platform/assert.h"
+#include "platform/utils.h"
+#include "vm/constants_dbc.h"
+#include "vm/cpu.h"
+#include "vm/hash_map.h"
+#include "vm/object.h"
+#include "vm/simulator.h"
+
+namespace dart {
+
+
+// Dummy declaration to make things compile.
+class Address : public ValueObject {
+ private:
+  Address();
+};
+
+
+class Label : public ValueObject {
+ public:
+  Label() : position_(0) { }
+
+  ~Label() {
+    // Assert if label is being destroyed with unresolved branches pending.
+    ASSERT(!IsLinked());
+  }
+
+  // Returns the position for bound and linked labels. Cannot be used
+  // for unused labels.
+  intptr_t Position() const {
+    ASSERT(!IsUnused());
+    return IsBound() ? -position_ - kWordSize : position_ - kWordSize;
+  }
+
+  bool IsBound() const { return position_ < 0; }
+  bool IsUnused() const { return position_ == 0; }
+  bool IsLinked() const { return position_ > 0; }
+
+ private:
+  intptr_t position_;
+
+  void Reinitialize() {
+    position_ = 0;
+  }
+
+  void BindTo(intptr_t position) {
+    ASSERT(!IsBound());
+    position_ = -position - kWordSize;
+    ASSERT(IsBound());
+  }
+
+  void LinkTo(intptr_t position) {
+    ASSERT(!IsBound());
+    position_ = position + kWordSize;
+    ASSERT(IsLinked());
+  }
+
+  friend class Assembler;
+  DISALLOW_COPY_AND_ASSIGN(Label);
+};
+
+
+class Assembler : public ValueObject {
+ public:
+  explicit Assembler(bool use_far_branches = false)
+      : buffer_(),
+        comments_() {
+  }
+
+  ~Assembler() { }
+
+  void Bind(Label* label);
+  void Jump(Label* label);
+
+  // Misc. functionality
+  intptr_t CodeSize() const { return buffer_.Size(); }
+  intptr_t prologue_offset() const { return 0; }
+
+  // Count the fixups that produce a pointer offset, without processing
+  // the fixups.
+  intptr_t CountPointerOffsets() const { return 0; }
+
+  const ZoneGrowableArray<intptr_t>& GetPointerOffsets() const {
+    ASSERT(buffer_.pointer_offsets().length() == 0);  // No pointers in code.
+    return buffer_.pointer_offsets();
+  }
+
+  ObjectPoolWrapper& object_pool_wrapper() { return object_pool_wrapper_; }
+
+  RawObjectPool* MakeObjectPool() {
+    return object_pool_wrapper_.MakeObjectPool();
+  }
+
+  void FinalizeInstructions(const MemoryRegion& region) {
+    buffer_.FinalizeInstructions(region);
+  }
+
+  // Debugging and bringup support.
+  void Stop(const char* message);
+  void Unimplemented(const char* message);
+  void Untested(const char* message);
+  void Unreachable(const char* message);
+
+  static void InitializeMemoryWithBreakpoints(uword data, intptr_t length);
+
+  void Comment(const char* format, ...) PRINTF_ATTRIBUTE(2, 3);
+  static bool EmittingComments();
+
+  const Code::Comments& GetCodeComments() const;
+
+  static const char* RegisterName(Register reg);
+
+  static const char* FpuRegisterName(FpuRegister reg) {
+    return "?";
+  }
+
+  static uword GetBreakInstructionFiller() {
+    return Bytecode::kTrap;
+  }
+
+  static bool IsSafe(const Object& value) { return true; }
+  static bool IsSafeSmi(const Object& value) { return false; }
+
+  // Bytecodes.
+
+#define DECLARE_EMIT(Name, Signature, Fmt0, Fmt1, Fmt2) \
+  void Name(PARAMS_##Signature);
+
+#define PARAMS_0
+#define PARAMS_A_D uintptr_t ra, uintptr_t rd
+#define PARAMS_D uintptr_t rd
+#define PARAMS_A_B_C uintptr_t ra, uintptr_t rb, uintptr_t rc
+#define PARAMS_A uintptr_t ra
+#define PARAMS_X intptr_t x
+#define PARAMS_T intptr_t x
+#define PARAMS_A_X uintptr_t ra, intptr_t x
+
+
+  BYTECODES_LIST(DECLARE_EMIT)
+
+#undef PARAMS_0
+#undef PARAMS_A_D
+#undef PARAMS_D
+#undef PARAMS_A_B_C
+#undef PARAMS_A
+#undef PARAMS_X
+#undef PARAMS_T
+#undef PARAMS_A_X
+#undef DECLARE_EMIT
+
+  void Emit(int32_t value);
+
+  void PushConstant(const Object& obj);
+  void LoadConstant(uintptr_t ra, const Object& obj);
+
+  intptr_t AddConstant(const Object& obj);
+
+ private:
+  AssemblerBuffer buffer_;  // Contains position independent code.
+  ObjectPoolWrapper object_pool_wrapper_;
+
+  class CodeComment : public ZoneAllocated {
+   public:
+    CodeComment(intptr_t pc_offset, const String& comment)
+        : pc_offset_(pc_offset), comment_(comment) { }
+
+    intptr_t pc_offset() const { return pc_offset_; }
+    const String& comment() const { return comment_; }
+
+   private:
+    intptr_t pc_offset_;
+    const String& comment_;
+
+    DISALLOW_COPY_AND_ASSIGN(CodeComment);
+  };
+
+  GrowableArray<CodeComment*> comments_;
+
+  DISALLOW_ALLOCATION();
+  DISALLOW_COPY_AND_ASSIGN(Assembler);
+};
+
+
+}  // namespace dart
+
+#endif  // VM_ASSEMBLER_DBC_H_