[llvm] [AArch64][ISel] Add support for v8.4a RCpc `ldapur`/`stlur` (PR #67879)

[David Green via llvm-commits]

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@@ -0,0 +1,375 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --filter-out "\b(sp)\b" --filter "^\s*(ld[^r]|st|swp|cas|bl|add|and|eor|orn|orr|sub|mvn|sxt|cmp|ccmp|csel|dmb)"
+; RUN: llc %s -o - -verify-machineinstrs -mtriple=aarch64 -mattr=+v8.4a -mattr=+rcpc-immo -O0 | FileCheck %s --check-prefixes=CHECK,O0-SDAG
+; RUN: llc %s -o - -verify-machineinstrs -mtriple=aarch64 -mattr=+v8.4a -mattr=+rcpc-immo -O1 | FileCheck %s --check-prefixes=CHECK,O1-SDAG
+; RUN: llc %s -o - -verify-machineinstrs -mtriple=aarch64 -mattr=+v8.4a -mattr=+rcpc-immo -global-isel -global-isel-abort=2 -O0 | FileCheck %s --check-prefixes=CHECK,GISEL
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davemgreen wrote:

I think it should be the case that -O0 runs global isel, and -O1 runs selections dag. It's probably better to be explicit though, and have one run line with -global-isel=true and another with -global-isel=false

https://github.com/llvm/llvm-project/pull/67879