[llvm] [AArch64][SelectionDAG] Add CodeGen support for scalar FEAT_CPA (PR #105669)

[David Green via llvm-commits]

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@@ -0,0 +1,451 @@
+; RUN: llc -mtriple=aarch64 -verify-machineinstrs --mattr=+cpa -O0 -global-isel=0 -fast-isel=0 %s -o - 2>&1 | FileCheck %s --check-prefixes=CHECK-CPA-O0
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davemgreen wrote:

Do the new instructions get used when you have +cpa? That sounds like it might cause a lot of regressions. It would probably be better to put them behind an option for now, until we are more confident about them. The user should opt into them when they are needed, not just when the instructions are available.

https://github.com/llvm/llvm-project/pull/105669