Program Reconditioning: Avoiding Undefined Behaviour When Finding and(…)
summary
Introduces reconditioning: generate potentially unsafe GPU programs, then apply a source-to-source reconditioner just before compilation so reduction never exposes undefined behaviour. Tools built are GLSLsmith and WGSLsmith for GLSL and WGSL, with concrete tactics like wrapping divisions, clamping array indices, determinizing floating-point evaluation, and initializing variables. Large campaign finds 24 bugs in GLSL and 33 bugs in WGSL. Does not handle concurrency and reconditioning can change behaviour when original code relied on UB.
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chapters (8)
- 0:00Introduction
- 1:50Compilation bugs and differential testing
- 3:58Program reduction challenges
- 5:21Undefined behavior in reduced programs
- 7:28Reconditioning for compiler testing
- 10:38Contributions and applications
- 12:42Limitations and future work
- 13:06Q&A
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