Runtime code generation in JVM and CLR

Here we present several complete examples of runtime code generation on these platforms. The purpose of this work is to investigate the suitability of these technologies that have recently entered the mainstream, and that can be expected to be widely available in the near future.

Further information about the examples, and results from experiments made with them, can be found here:

• Slides from NWPT 2005 and some associated code examples.
• A paper presenting somewhat improved results compared to those reported in the slides below.
• Lecture slides from a Coplas seminar given at DIKU on 26 September 2002.

Useful resources

• Sun HotSpot Java Virtual Machine
• IBM Java Developer Kit, including IBM's Java Virtual Machine
• Microsoft .Net SDK, including Common Language Runtime
• IBM Research Virtual Machine, also called Jikes RVM
• Open Runtime Platform (ORP), developed by Intel
• GNU lightning, a library for generating assembly language code at run-time

Overview of example programs

What is generated	C# version	Java version
A very simple method	RTCG1.cs
A method with integer argument and result	RTCG2.cs	RTCG2.java, RTCG2B.java
Methods that contain loops, for timing	RTCG3.cs	RTCG3.java
Specialized versions of the power function	RTCG4.cs	RTCG4.java, RTCG4B.java
Specialized evaluator for polynomials	RTCG5.cs
Specialized evaluator for arithmetic expressions	RTCG6.cs
Large methods, for timing of code generation	RTCG7.cs	RTCG7.java, RTCG7B.java
Specialized sparse matrix multiplication	RTCG8.cs	RTCG8.java
Specialized AES encryption/decryption routines	AesFast.cs, AesGen.cs
Efficient delegate objects in Java		Delegate.java, TryDelegate3.java, TryDelegate4.java