IMPROVING EMULATION AND TRACING PERFORMANCE USING COMPILER-GENERATED EMULATION OPTIMIZATION METADATA

摘要

An emulator can use compiler metadata to efficiently emulate execution of executable machine code compiled from the source code. Based on accessing compiler metadata associated with machine code, an emulator can identify behavior(s) of the source code from which the machine code is compiled which are not implied by the machine code. From these behaviors, the emulator can identify emulator optimization(s) that can be applied, during emulation of execution of a thread, to reduce a number of steps needed to emulate execution the machine code, while preserving any externally-visible side-effects. These optimizations can operate to reduce a number of emulator operations needed emulate execution of the machine code, or to elide one or more machine code instructions from emulation. These optimizations can then be applied while emulating execution of the thread. The emulated execution could be recorded to a trace that is equivalent to a trace recorded without these optimizations.