[llvm] [IR][RISCV] Add llvm.vector.(de)interleave3/5/7 (PR #124825)

[Min-Yih Hsu via llvm-commits]

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@@ -2728,6 +2740,54 @@ def int_vector_deinterleave2 : DefaultAttrsIntrinsic<[LLVMHalfElementsVectorType
                                                      [llvm_anyvector_ty],
                                                      [IntrNoMem]>;
 
+def int_vector_interleave3   : DefaultAttrsIntrinsic<[llvm_anyvector_ty],
+                                                     [LLVMOneThirdElementsVectorType<0>,
+                                                      LLVMOneThirdElementsVectorType<0>,
+                                                      LLVMOneThirdElementsVectorType<0>],
+                                                     [IntrNoMem]>;
+
+def int_vector_deinterleave3 : DefaultAttrsIntrinsic<[LLVMOneThirdElementsVectorType<0>,
+                                                      LLVMOneThirdElementsVectorType<0>,
+                                                      LLVMOneThirdElementsVectorType<0>],
+                                                     [llvm_anyvector_ty],
+                                                     [IntrNoMem]>;
+
+def int_vector_interleave5   : DefaultAttrsIntrinsic<[llvm_anyvector_ty],
+                                                     [LLVMOneFifthElementsVectorType<0>,
+                                                      LLVMOneFifthElementsVectorType<0>,
+                                                      LLVMOneFifthElementsVectorType<0>,
+                                                      LLVMOneFifthElementsVectorType<0>,
+                                                      LLVMOneFifthElementsVectorType<0>],
+                                                     [IntrNoMem]>;
+
+def int_vector_deinterleave5 : DefaultAttrsIntrinsic<[LLVMOneFifthElementsVectorType<0>,
+                                                      LLVMOneFifthElementsVectorType<0>,
+                                                      LLVMOneFifthElementsVectorType<0>,
+                                                      LLVMOneFifthElementsVectorType<0>,
+                                                      LLVMOneFifthElementsVectorType<0>],
+                                                     [llvm_anyvector_ty],
+                                                     [IntrNoMem]>;
+
+def int_vector_interleave7   : DefaultAttrsIntrinsic<[llvm_anyvector_ty],
+                                                     [LLVMOneSeventhElementsVectorType<0>,
+                                                      LLVMOneSeventhElementsVectorType<0>,
+                                                      LLVMOneSeventhElementsVectorType<0>,
+                                                      LLVMOneSeventhElementsVectorType<0>,
+                                                      LLVMOneSeventhElementsVectorType<0>,
+                                                      LLVMOneSeventhElementsVectorType<0>,
+                                                      LLVMOneSeventhElementsVectorType<0>],
+                                                     [IntrNoMem]>;
+
+def int_vector_deinterleave7 : DefaultAttrsIntrinsic<[LLVMOneSeventhElementsVectorType<0>,
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mshockwave wrote:

> Maybe we can also add 4/6/8 to simplify IR building? How do we handle 2/4/8 now? Do we need a combiner when selecting?

FYI: #123863 

https://github.com/llvm/llvm-project/pull/124825