1 files changed, 129 insertions, 0 deletions
diff --git a/compiler/utils/label.h b/compiler/utils/label.h
new file mode 100644
index 0000000000..ff4a1a4333
--- /dev/null
+++ b/compiler/utils/label.h
@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_COMPILER_UTILS_LABEL_H_
+#define ART_COMPILER_UTILS_LABEL_H_
+
+#include "base/logging.h"
+#include "base/macros.h"
+
+namespace art {
+
+class Assembler;
+class AssemblerBuffer;
+class AssemblerFixup;
+
+namespace arm {
+  class ArmAssembler;
+  class Arm32Assembler;
+  class Thumb2Assembler;
+}
+namespace arm64 {
+  class Arm64Assembler;
+}
+namespace mips {
+  class MipsAssembler;
+}
+namespace mips64 {
+  class Mips64Assembler;
+}
+namespace x86 {
+  class X86Assembler;
+  class NearLabel;
+}
+namespace x86_64 {
+  class X86_64Assembler;
+  class NearLabel;
+}
+
+class ExternalLabel {
+ public:
+  ExternalLabel(const char* name_in, uintptr_t address_in)
+      : name_(name_in), address_(address_in) {
+    DCHECK(name_in != nullptr);
+  }
+
+  const char* name() const { return name_; }
+  uintptr_t address() const {
+    return address_;
+  }
+
+ private:
+  const char* name_;
+  const uintptr_t address_;
+};
+
+class Label {
+ public:
+  Label() : position_(0) {}
+
+  ~Label() {
+    // Assert if label is being destroyed with unresolved branches pending.
+    CHECK(!IsLinked());
+  }
+
+  // Returns the position for bound and linked labels. Cannot be used
+  // for unused labels.
+  int Position() const {
+    CHECK(!IsUnused());
+    return IsBound() ? -position_ - sizeof(void*) : position_ - sizeof(void*);
+  }
+
+  int LinkPosition() const {
+    CHECK(IsLinked());
+    return position_ - sizeof(void*);
+  }
+
+  bool IsBound() const { return position_ < 0; }
+  bool IsUnused() const { return position_ == 0; }
+  bool IsLinked() const { return position_ > 0; }
+
+ private:
+  int position_;
+
+  void Reinitialize() {
+    position_ = 0;
+  }
+
+  void BindTo(int position) {
+    CHECK(!IsBound());
+    position_ = -position - sizeof(void*);
+    CHECK(IsBound());
+  }
+
+  void LinkTo(int position) {
+    CHECK(!IsBound());
+    position_ = position + sizeof(void*);
+    CHECK(IsLinked());
+  }
+
+  friend class arm::ArmAssembler;
+  friend class arm::Arm32Assembler;
+  friend class arm::Thumb2Assembler;
+  friend class arm64::Arm64Assembler;
+  friend class mips::MipsAssembler;
+  friend class mips64::Mips64Assembler;
+  friend class x86::X86Assembler;
+  friend class x86::NearLabel;
+  friend class x86_64::X86_64Assembler;
+  friend class x86_64::NearLabel;
+
+  DISALLOW_COPY_AND_ASSIGN(Label);
+};
+
+}  // namespace art
+
+#endif  // ART_COMPILER_UTILS_LABEL_H_