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Not Floating-point exceptions occurring during numerical computations can be a serious threat to the validity of the computed results if they are not caught and diagnosed Unfortunately, on NVIDIA GPUs-today's most widely used types and which do not have hardware exception traps-this task must be carried out in software. Given the prevalence of closed-source kernels, efficient binary-level exception tracking is essential. It is also important to know how exceptions flow through the code, whether they alter the code behavior and additionally whether these exceptions can be detected at the program outputs or are killed inside program flow-paths. In this paper, we introduce GPU-FPX, a tool that has low overhead, allows for deep understanding of the origin and flow of exceptions, and also how exceptions are modified by code optimizations. We measure GPU-FPX's performance over 151 widely used GPU programs coming from HPC and ML, detecting 26 serious exceptions that were previously not reported. Our results show that GPU-FPX is 16× faster with respect to the geometric-mean runtime in relation to the only comparable prior tool, while also helping debug a larger class of codes more effectively.
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D-REX: Static Detection of Relevant Runtime Exceptions with Location Aware Transformer
Runtime exceptions are inevitable parts of software systems. While developers often write exception handling code to avoid the severe outcomes of these exceptions, such code is most effective if accompanied by accurate runtime exception types. Predicting the runtime exceptions that may occur in a program, however, is difficult as the situations that lead to these exceptions are complex. We propose D-REX (Deep Runtime EXception detector), as an approach for predicting runtime exceptions of Java methods based on the static properties of code. The core of D-REX is a machine learning model that leverages the representation learning ability of neural networks to infer a set of signals from code to predict the related runtime exception types. This model, which we call Location Aware Transformer, adapts a state-of-the-art language model, Transformer, to provide accurate predictions for the exception types, as well as interpretable recommendations for the exception prone elements of code. We curate a benchmark dataset of 200,000 Java projects from GitHub to train and evaluate D-REX. Experiments demonstrate that D-REX predicts runtime exception types with 81% of Top 1 accuracy, outperforming multiple non-Transformer baselines by a margin of at least 12%. Furthermore, it can predict the exception prone elements of code with 75% Top 1 precision.
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- Award ID(s):
- 1823227
- PAR ID:
- 10296323
- Date Published:
- Journal Name:
- 2021 IEEE 21st International Working Conference on Source Code Analysis and Manipulation
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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