[clang] [llvm] [AArch64][clang][llvm] Add ACLE Armv9.7 lookup table intrinsics (PR #187046)

[Jonathan Thackray via cfe-commits]

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@@ -1371,13 +1370,28 @@ let TargetPrefix = "aarch64" in {  // All intrinsics start with "llvm.aarch64.".
                  LLVMVectorOfBitcastsToInt<0>],
                 !listconcat(Attrs, [IntrNoMem])>;
 
-  class SVE2_LUTI_Inrinsic<list<IntrinsicProperty> Attrs = []>
+  class SVE2_LUTI_Intrinsic<list<IntrinsicProperty> Attrs = []>
     :  DefaultAttrsIntrinsic<[llvm_anyvector_ty],
                 [LLVMMatchType<0>,
                  llvm_nxv16i8_ty,
                  llvm_i32_ty],
                  !listconcat(Attrs, [IntrNoMem, ImmArg<ArgIndex<2>>])>;
 
+  class SVE2_LUTI_X2_Intrinsic<list<IntrinsicProperty> Attrs = []>
+    : DefaultAttrsIntrinsic<[llvm_anyvector_ty],
+                [LLVMMatchType<0>,
+                 LLVMMatchType<0>,
+                 llvm_nxv16i8_ty,
+                 llvm_i32_ty],
+                !listconcat(Attrs, [IntrNoMem, ImmArg<ArgIndex<3>>])>;
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jthackray wrote:

The other `SVE_LUTI*_Intrinsic*`s nearby also use `!listconcat`, so we're following the same pattern. They all pass `IntrSpeculatable` (as do **loads** of other intrinsics). So I think to change this would require a much larger refactor of code. We're consistent here with other code, but it could be changed in future.

https://github.com/llvm/llvm-project/pull/187046