rnk added a comment. In http://reviews.llvm.org/D11437#211165, @chh wrote:
> I tried to make X86_64ABIInfo::classify to return (Lo=SSE, Hi=NoClass) for > fp128 long double type, or (Lo=SSE, Hi=SSEUp). That is not enough, although > making fp128 Complex type to "Memory" worked. > > X86_64ABIInfo::classifyArgumentType and classifyReturnType > will classify fp128 type as "double" through the help of GetSSETypeAtOffset. > These two or three functions still need more changes to handle fp128. > So I used the special cases for fp128, which seemed simpler with lower risk. > > The mapping to register classes is quite complicated to decide converted > parameter or return types. Although AMD64 spec has lengthy rules written this > way, the rules are quite difficult to understand the mapping of fp128 type. > > Is there other way to simplify these classification functions? I think the right approach is to classify as SSE+SSEUp. It didn't work for you because GetByteVectorType was turning fp128 types into <2 x double>, which will correctly use XMM registers, but is not the IR you wanted. I have a patch that fixes the TODOs and simplifies the code, do you mind if I land that? http://reviews.llvm.org/D11437 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
