Fix Z3 translation of ArraySlice and add fuzzing infrastructure.#4136
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Fix Z3 translation of ArraySlice and add fuzzing infrastructure.#4136copybara-service[bot] merged 1 commit intomainfrom
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The Z3 translation for ArraySlice is updated to correctly handle index addition by zero-extending the start index to prevent overflow. New tests are added to verify the equivalence of ArraySlice and ArrayIndex operations against alternative IR structures using both exhaustive simulation and Z3 proving. A fuzzing framework is introduced, which generates random IR, exhaustively interprets it to find all possible return values, and then builds a Z3 query to check if the fuzzed function's return value is always within this set of possible values. The fuzzer should hopefully (very slowly) prove that we do not have any similar translation bugs. PiperOrigin-RevId: 903299223
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Fix Z3 translation of ArraySlice and add fuzzing infrastructure.
The Z3 translation for ArraySlice is updated to correctly handle index addition by zero-extending the start index to prevent overflow. New tests are added to verify the equivalence of ArraySlice and ArrayIndex operations against alternative IR structures using both exhaustive simulation and Z3 proving. A fuzzing framework is introduced, which generates random IR, exhaustively interprets it to find all possible return values, and then builds a Z3 query to check if the fuzzed function's return value is always within this set of possible values.
The fuzzer should hopefully (very slowly) prove that we do not have any similar translation bugs.