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

[David Green via cfe-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
+; RUN: llc -mtriple=aarch64 -verify-machineinstrs --mattr=+cpa -O3 -global-isel=0 -fast-isel=0 %s -o - 2>&1 | FileCheck %s --check-prefixes=CHECK-CPA-O3
+; RUN: llc -mtriple=aarch64 -verify-machineinstrs --mattr=-cpa -O0 -global-isel=0 -fast-isel=0 %s -o - 2>&1 | FileCheck %s --check-prefixes=CHECK-NOCPA-O0
+; RUN: llc -mtriple=aarch64 -verify-machineinstrs --mattr=-cpa -O3 -global-isel=0 -fast-isel=0 %s -o - 2>&1 | FileCheck %s --check-prefixes=CHECK-NOCPA-O3
+
+%struct.my_type = type { i64, i64 }
+%struct.my_type2 = type { i64, i64, i64, i64, i64, i64 }
+
+ at array = external dso_local global [10 x %struct.my_type], align 8
+ at array2 = external dso_local global [10 x %struct.my_type2], align 8
+
+define void @addpt1(i64 %index, i64 %arg) {
+; CHECK-CPA-O0-LABEL:    addpt1:
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davemgreen wrote:

It helps keep the tests regular and easier to maintain. (If you don't do it now, someone will likely regenerate them in the future if they change). You might be able to use --check-prefixes=CHECK-CPA,CHECK-CPA-O0 if we expect the O0 and O3 codegen to be the same in some tests.

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