26 research outputs found
GPURepair: Automated Repair of GPU Kernels
This paper presents a tool for repairing errors in GPU kernels written in
CUDA or OpenCL due to data races and barrier divergence. Our novel extension to
prior work can also remove barriers that are deemed unnecessary for
correctness. We implement these ideas in our tool called GPURepair, which uses
GPUVerify as the verification oracle for GPU kernels. We also extend GPUVerify
to support CUDA Cooperative Groups, allowing GPURepair to perform inter-block
synchronization for CUDA kernels. To the best of our knowledge, GPURepair is
the only tool that can propose a fix for intra-block data races and barrier
divergence errors for both CUDA and OpenCL kernels and the only tool that fixes
inter-block data races for CUDA kernels. We perform extensive experiments on
about 750 kernels and provide a comparison with prior work. We demonstrate the
superiority of GPURepair through its capability to fix more kernels and its
unique ability to remove redundant barriers and handle inter-block data races.Comment: 19 pages, 1 algorithm, 3 figures, 22nd International Conference on
Verification Model Checking and Abstract Interpretation (VMCAI 2021
Independent prognostic value of coronary artery calcium score and coronary computed tomography angiography in an outpatient cohort of low to intermediate risk chest pain patients
Action of Aqueous Extracts of Phyllanthus niruri L. (Euphorbiaceae) leaves on Meristematic Root Cells of Allium cepa L.
Classifying ambiguous melanocytic lesions with FISH and correlation with clinical long-term follow up
Diagnostic value of coronary CT angiography with prospective ECG-gating in the diagnosis of coronary artery disease: a systematic review and meta-analysis
To perform a systematic review and meta-analysis of the diagnostic value of prospective ECG-gating coronary CT angiography in the diagnosis of coronary artery disease. A search of biomedical databases for English literature was performed to identify studies investigating the diagnostic value of 64- or more slice CT angiography with use of prospective ECG-gating in the diagnosis of coronary artery disease. Sensitivity, specificity, positive and negative predictive value estimates pooled across studies were tested using a fixed effects model. Fourteen studies met selection criteria for inclusion in the analysis. Pooled estimates and 95% confidence interval (CI) of sensitivity, specificity, positive and negative predictive value of prospective ECG-gating coronary CT angiography for diagnosis of significant coronary stenosis were 99% (95% CI: 98, 100%), 91% (95% CI: 88, 94%), 94% (95% CI: 91, 96%) and 99% (95% CI: 97, 100%), according to the patient-based assessment. The mean values of sensitivity, specificity, positive and negative predictive value of prospective ECG-gating coronary CT angiography were 95% (95% CI: 93, 96%), 95% (95% CI: 93, 95%), 88% (95% CI: 86, 90%), and 98% (95% CI: 97, 98%), according to vessel-based assessment; 92% (95% CI: 90, 93%), 97% (95% CI: 97, 98%), 84% (95% CI: 82, 86%), 99% (95% CI: 99, 99%), according to segment-based assessment, respectively. The mean effective dose was 3.3 mSv (95% CI: 2.3, 4.1 mSv) for the prospective ECG-gating coronary CT angiography. This analysis shows that for a predominantly male population with a high disease prevalence the use of coronary CT angiography with prospective ECG gating allows for a reduced radiation exposure without a sacrifice in diagnostic efficacy