Use the pydbreport and pydbexport utilities to classify errors and then reuse

Use the pydbreport and pydbexport utilities to

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Use the pydb_report and pydb_export utilities to classify errors, and then reuse the classification data. See “ pydb_report Utility ” and “ pydb_export Utility ” for more information. These utilities are in the IC Validator installation bin directory. You can also use VUE to classify and export errors. See the IC Validator VUE User Guide . Hierarchy Considerations in CELL_LEVEL Mode During preprocessing, the IC Validator function makes hierarchy optimizations. As a result, when error matching is done in CELL_LEVEL mode, errors could possibly be inconsistent between runs. To help prevent inconsistent hierarchy between runs, when an error classification database is imported, any cells defined within an error classification database
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Chapter 8: DRC Error Classification Using DRC Error Classification 8-3 IC Validator User Guide Version K-2015.06 are automatically protected from explosion during preprocessing. However, some optimizations create hierarchy, or explode or flatten individual placements of cells, and therefore, can create consistency problems. When running the DRC error classification flow in CELL_LEVEL mode, always set the flow argument in the hierarchy_auto_options() function to the ERROR_CLASSIFICATION option. See the hierarchy_auto_options() function. Hierarchical DRC Error Classification The IC Validator tool provides a HIERARCHICAL mode for error classification matching that is more robust and less sensitive to hierarchy changes than CELL_LEVEL mode. This mode puts no restrictions on hierarchy optimization. Cells that have classified errors in the error classification database (cPYDB) are allowed to explode. An error is considered a match for a classified error from the cPYDB if the complete hierarchically formed shape of the errors produced by the IC Validator tool exactly overlaps the complete hierarchically formed shape of errors from the cPYDB with the same classification. If any part of the complete shape is different between the errors found by the IC Validator tool and the errors from the cPYDB, it is not a hierarchical match. However, in this mode, errors can also be matched individually when possible. That is, when a single error, rather than the complete hierarchically formed shape consisting of multiple errors, exactly overlaps a corresponding single error in the cPYDB it is considered a match, even if it is at a different level of hierarchy. Error Classification Best Practices It is important to make the distinction between classified errors in the error classification database (cPYDB) that are referenced by rule, or violation comment, and errors produced by the IC Validator tool that are created by a command. The recommended best practice to ensure proper error matching is to output all of the violations for a rule with a single IC Validator command. This avoids the possibility of errors from different commands within the same rule interacting in the cPYDB and preventing a hierarchical match when they are considered for an individual command in a subsequent run. Violation comments should be
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  • Fall '18
  • Electronic design automation, The Run, Data-flow analysis, Definite assignment analysis, IC Validator

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