# GraalVM Changelog

This changelog summarizes major changes between Graal versions relevant to languages implementors building upon the Truffle framework and developers building technology on top of Graal. The main focus is on APIs exported by Graal and Truffle.


## `tip`
### Graal
* ...

### Truffle
* Added Node#deepCopy as primary method to copy ASTs.

## Version 0.6
19-Dec-2014, [Repository Revision](http://hg.openjdk.java.net/graal/graal/shortlog/graal-0.6)
### Graal
* Merged with jdk8u25-b17.
* Added `com.oracle.graal.api.meta.Remote` interface for future support of remote and replay compilation.
* Changed name suite specification from `mx/projects.py` to `mx/suite.py`.
* Changed semantics (and signature) of `ResolvedJavaType#resolveMethod()` (old behavior available via `resolveConcreteMethod()`).
* Moved `ResolvedJavaField#read[Constant]Value` and `getMethodHandleAccess()` to `ConstantReflectionProvider`.

### Truffle
* Instrumentation: add Instrumentable API for language implementors, with most details automated (see package `com.oracle.truffle.api.instrument`).
* The BranchProfile constructor is now private. Use BranchProfile#create() instead.
* Renamed @CompilerDirectives.SlowPath to @CompilerDirectives.TruffleBoundary
* Renamed RootNode#isSplittable to RootNode#isCloningAllowed
* Removed RootNode#split. Cloning ASTs for splitting is now an implementation detail of the Truffle runtime implementation. 
* Renamed DirectCallNode#isSplittable to DirectCallNode#isCallTargetCloningAllowed
* Renamed DirectCallNode#split to DirectCallNode#cloneCallTarget
* Renamed DirectCallNode#isSplit to DirectCallNode#isCallTargetCloned
* Added PrimitiveValueProfile.
* Added -G:TruffleTimeThreshold=5000 option to defer compilation for call targets
* Added RootNode#getExecutionContext to identify nodes with languages
* Removed `FrameTypeConversion` interface and changed the corresponding `FrameDescriptor` constructor to have a default value parameter instead.
* Removed `CompilerDirectives.unsafeFrameCast` (equivalent to a `(MaterializedFrame)` cast).
* Added `TruffleRuntime#getCapability` API method.
* Added `NodeInterface` and allowed child field to be declared with interfaces that extend it.
* Added `CompilerOptions` and allowed it to be set for `ExecutionContext` and `RootNode`.
* Added experimental object API (see new project `com.oracle.truffle.api.object`).

## Version 0.5
23-Sep-2014, [Repository Revision](http://hg.openjdk.java.net/graal/graal/shortlog/graal-0.5)
### Graal
* New register allocator optimization: `-G:+ConstantLoadOptimization`.
* SPARC backend is able to run benchmark and passing most of the JTTs.
* Fix: Stamp: interface types can not be trusted except after explicit runtime checks.
* Changed format of suite specification from a properties file (`mx/projects`) to a Python file (`mx/projects.py`).


### Truffle
* Added `TruffleRuntime#getCallTargets()` to get all call targets that were created and are still referenced.
* Added `NeverValidAssumption` to complement `AlwaysValidAssumption`.
* Fixed a bug in `AssumedValue` that may not invalidate correctly.
* New option, `-G:+/-TruffleCompilationExceptionsAreThrown`, that will throw an `OptimizationFailedException` for compiler errors.

## Version 0.4
19-Aug-2014, [Repository Revision](http://hg.openjdk.java.net/graal/graal/shortlog/graal-0.4)
### Graal
* Made initialization of Graal runtime lazy in hosted mode.
* Added supported for new `jrelibrary` dependency type in `mx/projects`.
* Java projects with compliance level higher than the JDKs specified by `JAVA_HOME` and `EXTRA_JAVA_HOMES` are ignored once `mx/projects` has been processed.
* `ResolvedJavaType.resolveMethod` now takes a context type used to perform access checks. It now works correctly regarding default methods.
* Removed Java based compilation queue (`CompilationQueue.java`).
* Enabled use of separate class loader (via `-XX:+UseGraalClassLoader`) for classes loaded from `graal.jar` to hide them from application classes.

### Truffle
* Change API for stack walking to a visitor: `TruffleRuntime#iterateFrames` replaces `TruffleRuntime#getStackTrace`
* New flag `-G:+TraceTruffleCompilationCallTree` to print the tree of inlined calls before compilation.
* `truffle.jar`: strip out build-time only dependency into a seperated JAR file (`truffle-dsl-processor.jar`)
* New flag `-G:+TraceTruffleCompilationAST` to print the AST before compilation.
* New experimental `TypedObject` interface added.
* Renamed flag `-G:+TruffleSplittingEnabled` to `-G:+TruffleSplitting`
* New flag `-G:+TruffleSplittingNew` to enable the experimental splitting mode based on function arguments.
* New flag `-G:+TruffleSplittingTypedInstanceStamps` to enable splitting for `TypedObject` instances.
* New flag `-G:+TruffleSplittingClassInstanceStamps` to enable splitting for Java object instances except `TypedObject`.
* New flag `-G:TruffleSplittingStartCallCount=3` which sets the number of minimal calls until splitting is performed.
* New flag `-G:-TruffleSplittingAggressive` if enabled splits every function call.
* Added `isVisited` method for `BranchProfile`.
* Added new `ConditionProfile`, `BinaryConditionProfile` and `CountingConditionProfile` utility classes to profile if conditions.

## Version 0.3
9-May-2014, [Repository Revision](http://hg.openjdk.java.net/graal/graal/shortlog/graal-0.3)

### Graal
* Explicit support for oop compression/uncompression in high level graph.
* LIRGenerator refactoring.
* Explicit types for inputs (InputType enum).
* Added graal.version system property to Graal enabled VM builds.
* Transitioned to JDK 8 as minimum JDK level for Graal.
* Added support for stack introspection.
* New MatchRule facility to convert multiple HIR nodes into specialized LIR

### Truffle
* The method `CallTarget#call` takes now a variable number of Object arguments.
* Support for collecting stack traces and for accessing the current frame in slow paths (see `TruffleRuntime#getStackTrace`).
* Renamed `CallNode` to `DirectCallNode`.
* Renamed `TruffleRuntime#createCallNode` to `TruffleRuntime#createDirectCallNode`.
* Added `IndirectCallNode` for calls with a changing `CallTarget`.
* Added `TruffleRuntime#createIndirectCallNode` to create an `IndirectCallNode`.
* `DirectCallNode#inline` was renamed to `DirectCallNode#forceInlining()`.
* Removed deprecated `Node#adoptChild`.

## Version 0.2
25-Mar-2014, [Repository Revision](http://hg.openjdk.java.net/graal/graal/shortlog/graal-0.2)

### Graal
* Use HotSpot stubs for certain array copy operations.
* New methods for querying memory usage of individual objects and object graphs in Graal API (`MetaAccessProvider#getMemorySize`, `MetaUtil#getMemorySizeRecursive`).
* Added tiered configuration (C1 + Graal).
* Initial security model for Graal [GRAAL-22](https://bugs.openjdk.java.net/browse/GRAAL-22).
* New (tested) invariant that equality comparisons for `JavaType`/`JavaMethod`/`JavaField` values use `.equals()` instead of `==`.
* Made graph caching compilation-local.
* Added AllocSpy tool for analyzing allocation in Graal using the [Java Allocation Instrumenter](https://code.google.com/p/java-allocation-instrumenter/).
* Initial support for memory arithmetic operations on x86.
* Expanded Debug logging/dumping API to avoid allocation when this Debug facilities are not enabled.

### Truffle
* New API `TruffleRuntime#createCallNode` to create call nodes and to give the runtime system control over its implementation.
* New API `RootNode#getCachedCallNodes` to get a weak set of `CallNode`s that have registered to call the `RootNode`.
* New API to split the AST of a call-site context sensitively. `CallNode#split`, `CallNode#isSplittable`, `CallNode#getSplitCallTarget`, `CallNode#getCurrentCallTarget`, `RootNode#isSplittable`, `RootNode#split`.
* New API to inline a call-site into the call-graph. `CallNode#isInlinable`, `CallNode#inline`, `CallNode#isInlined`.
* New API for the runtime environment to register `CallTarget`s as caller to the `RootNode`. `CallNode#registerCallTarget`.
* Improved API for counting nodes in Truffle ASTs. `NodeUtil#countNodes` can be used with a `NodeFilter`.
* New API to declare the cost of a Node for use in runtime environment specific heuristics. See `NodeCost`, `Node#getCost` and `NodeInfo#cost`.
* Removed old API for `NodeInfo#Kind` and `NodeInfo#kind`. As a replacement the new `NodeCost` API can be used.
* Changed `Node#replace` reason parameter type to `CharSequence` (to enable lazy string building)
* Deprecated `Node#adoptChild` and `Node#adoptChildren`, no longer needed in node constructor
* New `Node#insert` method for inserting new nodes into the tree (formerly `adoptChild`)
* New `Node#adoptChildren` helper method that adopts all (direct and indirect) children of a node
* New API `Node#atomic` for atomic tree operations
* Made `Node#replace` thread-safe


## Version 0.1
5-Feb-2014, [Repository Revision](http://hg.openjdk.java.net/graal/graal/shortlog/graal-0.1)

### Graal

* Initial version of a dynamic Java compiler written in Java.
* Support for multiple co-existing GPU backends ([GRAAL-1](https://bugs.openjdk.java.net/browse/GRAAL-1)).
* Fixed a compiler bug when running RuneScape ([GRAAL-7](https://bugs.openjdk.java.net/browse/GRAAL-7)).
* Bug fixes ([GRAAL-4](https://bugs.openjdk.java.net/browse/GRAAL-4), [GRAAL-5](https://bugs.openjdk.java.net/browse/GRAAL-5)).

### Truffle

* Initial version of a multi-language framework on top of Graal.
* Update of the [Truffle Inlining API](http://mail.openjdk.java.net/pipermail/graal-dev/2014-January/001516.html).