Correctly reverse translate GEP coming from G_PTR_ADD#166
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AlexVlx
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G_PTR_ADD
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MrSidims
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May 5, 2026
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I'm not exactly following the problem - a test should help.
Source of my non-understanding comes from the fact, that now days clang more often generates ptradd-like GEP (with a byte base). And so far I've seen no issues with translation of such GEPs. And my expectation is that the result of the codegen by the backend should look exactly the same as flattening done by clang. If it's not the case it means either of 2 things: a. corner case which I should learn about (and a test should help with that :) ) or b. bug in the backend.
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+1 to @MrSidims's comment. A test/example would help me understand the issue. |
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When using the BE,
ConstantExprGEPs can get flattened into a G_PTR_ADD, which then gets lowered into anOpPtrAccessChain. When we reverse translate, we have access to the full type, which might not be flat / for which the flat index as computed for a G_PTR_ADD might be incorrect. This patch recomputes the index vector based on type and offset for such cases.