lambda: Infrastructure to support capture/liberate-variable dex opcodes
* ArtLambdaMethod - wrap an ArtMethod with extra runtime lambda info
* Closure - data representation for a runtime lambda closure (read-only)
* ClosureBuilder - writer for creating a Closure at runtime
* ShortyFieldType - char/enum wrapper for shorty_field_type in dex
Tests:
* Closure, ClosureBuilder, ShortyFieldType have full unit test coverage.
* ArtLambdaMethod does not, but it is tested indirectly and is otherwise
trivial getters.
Future CLs will include interpreter integration with minimal changes to
this Closure infrastructure.
Change-Id: I38a7aea8df1da7b154fd6623258c6c228c8e51df
diff --git a/runtime/lambda/closure_builder.h b/runtime/lambda/closure_builder.h
new file mode 100644
index 0000000..542e12a
--- /dev/null
+++ b/runtime/lambda/closure_builder.h
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2015 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_RUNTIME_LAMBDA_CLOSURE_BUILDER_H_
+#define ART_RUNTIME_LAMBDA_CLOSURE_BUILDER_H_
+
+#include "base/macros.h"
+#include "base/mutex.h" // For Locks::mutator_lock_.
+#include "base/value_object.h"
+#include "lambda/shorty_field_type.h"
+
+#include <stdint.h>
+#include <vector>
+
+namespace art {
+class ArtMethod; // forward declaration
+
+namespace mirror {
+class Object; // forward declaration
+} // namespace mirror
+
+namespace lambda {
+class ArtLambdaMethod; // forward declaration
+
+// Build a closure by capturing variables one at a time.
+// When all variables have been marked captured, the closure can be created in-place into
+// a target memory address.
+//
+// The mutator lock must be held for the duration of the lifetime of this object,
+// since it needs to temporarily store heap references into an internal list.
+class ClosureBuilder : ValueObject {
+ public:
+ using ShortyTypeEnum = decltype(ShortyFieldType::kByte);
+
+
+ // Mark this primitive value to be captured as the specified type.
+ template <typename T, ShortyTypeEnum kShortyType>
+ void CaptureVariablePrimitive(T value);
+
+ // Mark this object reference to be captured.
+ void CaptureVariableObject(mirror::Object* object) SHARED_REQUIRES(Locks::mutator_lock_);
+
+ // Mark this lambda closure to be captured.
+ void CaptureVariableLambda(Closure* closure);
+
+ // Get the size (in bytes) of the closure.
+ // This size is used to be able to allocate memory large enough to write the closure into.
+ // Call 'CreateInPlace' to actually write the closure out.
+ size_t GetSize() const;
+
+ // Returns how many variables have been captured so far.
+ size_t GetCaptureCount() const;
+
+ // Creates a closure in-place and writes out the data into 'memory'.
+ // Memory must be at least 'GetSize' bytes large.
+ // All previously marked data to be captured is now written out.
+ Closure* CreateInPlace(void* memory, ArtLambdaMethod* target_method) const
+ SHARED_REQUIRES(Locks::mutator_lock_);
+
+ // Locks need to be held for entire lifetime of ClosureBuilder.
+ ClosureBuilder() SHARED_REQUIRES(Locks::mutator_lock_)
+ {}
+
+ // Locks need to be held for entire lifetime of ClosureBuilder.
+ ~ClosureBuilder() SHARED_REQUIRES(Locks::mutator_lock_)
+ {}
+
+ private:
+ // Initial size a closure starts out before any variables are written.
+ // Header size only.
+ static constexpr size_t kInitialSize = sizeof(ArtLambdaMethod*);
+
+ // Write a Closure's variables field from the captured variables.
+ // variables_size specified in bytes, and only includes enough room to write variables into.
+ // Returns the calculated actual size of the closure.
+ size_t WriteValues(ArtLambdaMethod* target_method,
+ uint8_t variables[],
+ size_t header_size,
+ size_t variables_size) const SHARED_REQUIRES(Locks::mutator_lock_);
+
+ size_t size_ = kInitialSize;
+ bool is_dynamic_size_ = false;
+ std::vector<ShortyFieldTypeTraits::MaxType> values_;
+};
+
+} // namespace lambda
+} // namespace art
+
+#endif // ART_RUNTIME_LAMBDA_CLOSURE_BUILDER_H_