[llvm] [AArch64] Create set.fpmr intrinsic and assembly lowering (PR #114248)

[Paul Walker via llvm-commits]

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@@ -778,6 +778,9 @@ def int_aarch64_get_fpcr : FPENV_Get_Intrinsic;
 def int_aarch64_set_fpcr : FPENV_Set_Intrinsic;
 def int_aarch64_get_fpsr : FPENV_Get_Intrinsic;
 def int_aarch64_set_fpsr : FPENV_Set_Intrinsic;
+def int_aarch64_set_fpmr : DefaultAttrsIntrinsic<[], [llvm_i64_ty], [IntrInaccessibleMemOnly]>{
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paulwalker-arm wrote:

Perhaps just add an `FPMR_Set_Intrinsic` class to sit along side the existing FPENV ones.

https://github.com/llvm/llvm-project/pull/114248