Abstract: Methods and apparatus, including computer program products, are provided for debugging using dynamic compilers. The method may include receiving a first indication to grant access to a set of variables and to allow access to be inhibited to a set of remaining variables. The dynamic compiler may be allowed to optimize the set of remaining variables, while the set of granted variables is preserved. A second indication may be provided to acknowledge access to the set of granted variables and allow access to be inhibited to the set of remaining variables. In some variations, the set of granted variables is implemented as a set of live variables and the set of remaining variables is implemented as a set of dead variables. Related apparatus, systems, methods, and articles are also described.

Abstract: A system and method to perform post pass optimizations in a dynamic compiling environment. A dynamic compiler emits machine code. Responsive to the emission of the machine code a post pass processor creates an abstract representation of the code from the dynamic compiler. Data flow analysis is then conducted on the abstract representation. Redundant instructions in the machine code are identified and eliminated as a result of the data flow analysis.

Abstract: Methods and apparatus, including computer program products, for measuring the performance of aspects of a complex data processing system. In one aspect, a method uses a dynamic synthetic benchmark to provide performance information for a program application running on a virtual machine. The benchmark in one implementation uses a load profile that includes information about instructions that make up the application, their call frequencies, and their workloads. Microbenchmarks of individual virtual machine instructions provide performance information about the virtual machine that is used with the load profile to synthesize a performance benchmark for the application.

Abstract: Methods and apparatus, including computer program products, are provided for debugging using dynamic compilers. The method may include receiving a first indication to grant access to a set of variables and to allow access to be inhibited to a set of remaining variables. The dynamic compiler may be allowed to optimize the set of remaining variables, while the set of granted variables is preserved. A second indication may be provided to acknowledge access to the set of granted variables and allow access to be inhibited to the set of remaining variables. In some variations, the set of granted variables is implemented as a set of live variables and the set of remaining variables is implemented as a set of dead variables. Related apparatus, systems, methods, and articles are also described.

Abstract: A system and method to perform post pass optimizations in a dynamic compiling environment. A dynamic compiler emits machine code. Responsive to the emission of the machine code a post pass processor creates an abstract representation of the code from the dynamic compiler. Data flow analysis is then conducted on the abstract representation. Redundant instructions in the machine code are identified and eliminated as a result of the data flow analysis.

Abstract: Methods and apparatus, including computer program products, for measuring the performance of aspects of a complex data processing system. In one aspect, a method uses a dynamic synthetic benchmark to provide performance information for a program application running on a virtual machine. The benchmark in one implementation uses a load profile that includes information about instructions that make up the application, their call frequencies, and their workloads. Microbenchmarks of individual virtual machine instructions provide performance information about the virtual machine that is used with the load profile to synthesize a performance benchmark for the application.