[llvm] [LTO] Set default Darwin CPU to apple-a7 for AArch64 (PR #81540)

[Jon Roelofs via llvm-commits]

================
@@ -546,8 +546,11 @@ static void initTMBuilder(TargetMachineBuilder &TMBuilder,
       TMBuilder.MCpu = "core2";
     else if (TheTriple.getArch() == llvm::Triple::x86)
       TMBuilder.MCpu = "yonah";
-    else if (TheTriple.getArch() == llvm::Triple::aarch64 ||
-             TheTriple.getArch() == llvm::Triple::aarch64_32)
+    else if (TheTriple.isArm64e())
+      TMBuilder.MCpu = "apple-a12";
----------------
jroelofs wrote:

This is a functional change, and should come with a test.

https://github.com/llvm/llvm-project/pull/81540