[LLVMdev] larger-than-legal types in LLVM IR (original) (raw)
Sanjay Patel spatel at rotateright.com
Mon Jan 19 16:38:11 PST 2015
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Are there any LLVM guidelines / documentation for handling larger-than-legal data types (either scalars or vectors)?
Currently, the backend may crash [1], miscompile [2], or make a big mess [3] when presented with data types that are bigger than native.
In the case of [3], is it a bug in the vectorizer to produce a non-legal vector type (<16 x i64>) or should the backend be able to handle that more reasonably? In that particular case, things are further complicated because -loop-unroll is able to completely remove the loop and the large vector type disappears.
[1] http://llvm.org/bugs/show_bug.cgi?id=19797 [2] http://llvm.org/bugs/show_bug.cgi?id=21184 [3] http://llvm.org/bugs/show_bug.cgi?id=20225 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20150119/6433cb7c/attachment.html>
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