runtime: Add lambda box/unbox object equality
A lambda that is boxed with box-lambda is now stored as a weak reference
in a global runtime table (lambda::BoxTable). Repeatedly boxing the same
lambda closure value will always return the same java.lang.Object back.
Since there is no way to observe the address of an object, a GC can
happen and clean up the table of any dead boxed lambdas, which can also
shrink the table to prevent the memory use from growing too much.
(Note that a lambda closure is immutable, so hashing over it is
guaranteed safe.)
Change-Id: I786c1323ff14eed937936b303d511875f9642524
diff --git a/runtime/runtime.h b/runtime/runtime.h
index 806292f..55adaf1 100644
--- a/runtime/runtime.h
+++ b/runtime/runtime.h
@@ -53,6 +53,10 @@
class JitOptions;
} // namespace jit
+namespace lambda {
+ class BoxTable;
+} // namespace lambda
+
namespace mirror {
class ClassLoader;
class Array;
@@ -532,6 +536,10 @@
return experimental_lambdas_;
}
+ lambda::BoxTable* GetLambdaBoxTable() const {
+ return lambda_box_table_.get();
+ }
+
// Create the JIT and instrumentation and code cache.
void CreateJit();
@@ -646,6 +654,8 @@
std::unique_ptr<jit::Jit> jit_;
std::unique_ptr<jit::JitOptions> jit_options_;
+ std::unique_ptr<lambda::BoxTable> lambda_box_table_;
+
// Fault message, printed when we get a SIGSEGV.
Mutex fault_message_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
std::string fault_message_ GUARDED_BY(fault_message_lock_);