[llvm] [ARM] Explicitly mark certain instructions as having no side effects. (PR #182771)

[Eli Friedman via llvm-commits]

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@@ -397,9 +397,6 @@ def tPICADD : TIt<(outs GPR:$dst), (ins GPR:$lhs, pclabel:$cp), IIC_iALUr, "",
 }
 
 // ADD <Rd>, sp, #<imm8>
-// FIXME: This should not be marked as having side effects, and it should be
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efriedma-quic wrote:

This dates back to dd2b39d989e58bcad3014d8834f1af932426f9d1 .  I have no idea if there's actually an issue anymore... but please verify we have some test coverage for the interaction between this and call frames.

https://github.com/llvm/llvm-project/pull/182771