Fix llvm.aarch64.irg properties.

[eugenis]

Summary

IRG does not access any memory.
Replace IntrInaccessibleMemOnly with IntrNoMem | IntrHasSideEffects.

[eugenis]

TBH I have no idea how to test this.

[chill]

I suggested this change here: https://reviews.llvm.org/D60486#inline-574695
But I've got the feeling (from https://reviews.llvm.org/D64414) it a subject for a debate.

[jdoerfert]

In D64447#1577108, @eugenis wrote:

TBH I have no idea how to test this.

Is there a builtin that lowers to this, e.g., we test it by lowering C -> IR -> asm, and we can check the properties/attributes on the lower levels.
If not, we could probably start at the IR level, lower to asm, and check the final properties.

[eugenis]

added a test

[jdoerfert]

LGTM

llvm/include/llvm/IR/IntrinsicsAArch64.td

 def int_aarch64_crc32cx : Intrinsic<[llvm_i32_ty], [llvm_i32_ty, llvm_i64_ty],
     [IntrNoMem]>;
 }
 
 //===----------------------------------------------------------------------===//
 // Memory Tagging Extensions (MTE) Intrinsics
 let TargetPrefix = "aarch64" in {
 def int_aarch64_irg   : Intrinsic<[llvm_ptr_ty], [llvm_ptr_ty, llvm_i64_ty],
-    [IntrInaccessibleMemOnly]>;
+    [IntrNoMem, IntrHasSideEffects]>;
 def int_aarch64_addg  : Intrinsic<[llvm_ptr_ty], [llvm_ptr_ty, llvm_i64_ty],
     [IntrNoMem]>;
 def int_aarch64_gmi   : Intrinsic<[llvm_i64_ty], [llvm_ptr_ty, llvm_i64_ty],
     [IntrNoMem]>;
 def int_aarch64_ldg   : Intrinsic<[llvm_ptr_ty], [llvm_ptr_ty, llvm_ptr_ty],
     [IntrReadMem]>;
 def int_aarch64_stg   : Intrinsic<[], [llvm_ptr_ty, llvm_ptr_ty],
     [IntrWriteMem]>;
 def int_aarch64_subp :  Intrinsic<[llvm_i64_ty], [llvm_ptr_ty, llvm_ptr_ty],
     [IntrNoMem]>;
 }