Check types when applying inverse cond pattern#323
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viktormalik merged 1 commit intodiffkemp:masterfrom Mar 26, 2024
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Check types when applying inverse cond pattern#323viktormalik merged 1 commit intodiffkemp:masterfrom
viktormalik merged 1 commit intodiffkemp:masterfrom
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Looks great, just one nit. Thanks!
In certain conditions, not checking the type could lead to an assertion failure in cmpOperationsWithOperands. FunctionComparator::cmpOperations checks the types of operands, however if the instructions are an inverse icmp instructions, Diffkemp discards this result. We need to differentiate, whether the non-zero return code from cmpOperations was caused by a difference in types or difference in values before applying the pattern.
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In certain conditions, not checking the type could lead to an assertion failure in cmpOperationsWithOperands. FunctionComparator::cmpOperations checks the types of operands, however if the instructions are an inverse icmp instructions, Diffkemp discards this result. We need to differentiate, whether the non-zero return code from cmpOperations was caused by a difference in types or difference in values before applying the pattern.
The attached test resulted in an assertion failure with current diffkemp version on this line:
diffkemp/diffkemp/simpll/DifferentialFunctionComparator.cpp
Lines 1849 to 1850 in 789ac18
I thought of two possible solutions to this problem:
DifferentialFunctionComparator::cmpValuesThe second option sounds a bit cleaner but I feel like it could have some side-effects that I may not be aware of (since the method is called quite often from various contexts) and it may be intentional that the comparison is left out. Therefore, I decided to use the "safer" alternative.