scalable vecs size incl. num vecs + no sret for scalable vecs#157915
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scalable vecs size incl. num vecs + no sret for scalable vecs#157915davidtwco wants to merge 2 commits into
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The correct size for `Layout` of a scalable vector ought to include the number of vectors, otherwise we generate `memcpy` that do not copy the entire vector and things like that.
rustc typically uses a return area pointer if the size of a return value is larger than two pointers, except for SIMD vectors and now scalable vectors. Given the previous commit, scalable types are more likely to trigger this conditional than previously. This is already tested in the output of the `codegen-llvm/scalable-vectors/tuple-intrinsics.rs` test.
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The correct size for
Layoutof a scalable vector ought to include the number of vectors, otherwise we generatememcpythat do not copy the entire vector and things like that. This is tested inui/scalable-vectors/layout.rs.Additionally, rustc typically uses a return area pointer if the size of a return value is larger than two pointers, except for SIMD vectors and now scalable vectors. Given the previous change, scalable types are more likely to trigger this conditional than previously. This is already tested in the output of the
codegen-llvm/scalable-vectors/tuple-intrinsics.rstest.r? @lqd