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SUMMARY In a virtual machine interpreter, the code for each virtual machine instruction has similarities to code for other instructions. We present an interpreter generator that takes simple virtual machine instruction descriptions as input and generates C code for processing the instructions in several ways: execution, virtual machine code generation,(More)
Romer et al (ASPLOS 96) examined several interpreters and concluded that they behave much like general purpose integer programs such as gcc. We show that there is an important class of interpreters which behave very differently. Efficient virtual machine interpreters perform a large number of indirect branches (3.2%–13% of all executed instructions in our(More)
Although scripting languages are becoming increasingly popular, even mature scripting language implementations remain interpreted. Several compilers and reimplementations have been attempted, generally focusing on performance. Based on our survey of these reimplementations, we determine that there are three important features of scripting languages that(More)
Dynamic scripting languages offer programmers increased flexibility by allowing properties of programs to be defined at run-time. Typically, program execution begins with an interpreter where type checks are implemented using conditional statements. Recent JIT compilers have begun removing run-time checks by specializing native code to program properties(More)
Interpreters designed for efficiency execute a huge number of indirect branches and can spend more than half of the execution time in indirect branch mispredictions. Branch target buffers are the best widely available form of indirect branch prediction; however, their prediction accuracy for existing interpreters is only 2%--50%. In this paper we(More)
In this paper we present a platform independent analysis of the dynamic profiles of Java programs when executing on the Java Virtual Machine. The Java programs selected are taken from the Java Grande Forum benchmark suite, and five different Java-to-bytecode compilers are analysed. The results presented describe the dynamic instruction usage frequencies, as(More)
Virtual machines (VMs) enable the distribution of programs in an architecture-neutral format, which can easily be interpreted or compiled. A long-running question in the design of VMs is whether a stack architecture or register architecture can be implemented more efficiently with an interpreter. We extend existing work on comparing virtual stack and(More)