structmemfunclowering: fix crash when gep is optimized away #203
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llvm is removing getPointerElementType(), so maybe that's why we do the overkill cast there. At some point we started removing all the "easy" cases of getPointerElementType usage. |
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What is the actual type that we are trying to cast? |
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In the example from issue from cheerp-meta, it was |
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Ah I see that it's a completely degenerate case. Can we just skip applying the pass in this case? |
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I'll check, I also saw this commit which I believe was never merged, it might also solve it: |
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or even assuming that the type is char* if it's not inferrable from a gep |
LLVM is smart enough to be able to fold a gep if the source and indices are constants. However, it was assumed that it would always emit a gep instruction, which would cause a crash when trying to cast it. Upon further inspection, I believe that the surrounding if statement was meant as a way of working around one of such folds. The new code should work for the general case, so I've removed it. This fixes: leaningtech/cheerp-meta#141
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I've removed the use of |
LLVM is smart enough to be able to remove a gep if the source and indexes are constants. However, it was assumed that it would always emit a gep instruction, which would cause a crash when trying to cast it.
Upon further inspection, I believe that this casting to a GEPOperator and then getting the result element type is overkill, and we could just simply use the type of the value.
This fixes: leaningtech/cheerp-meta#141