[llvm] [IR] Add `llvm.sincos` intrinsic (PR #109825)

[Benjamin Maxwell via llvm-commits]

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@@ -0,0 +1,516 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 2
+; RUN: llc -mtriple=aarch64-gnu-linux < %s | FileCheck -check-prefixes=CHECK %s
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MacDue wrote:

I've added tests where the libcall is unavailable (and so the intrinsic is expanded to individual sin/cos calls) :+1: 

https://github.com/llvm/llvm-project/pull/109825