[clang] [NFC][clang] Split clang/lib/CodeGen/CGBuiltin.cpp into target-specific files (PR #132252)

[David Green via cfe-commits]

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@@ -0,0 +1,8040 @@
+//===------ AArch64.cpp - Emit LLVM Code for builtins ---------------------===//
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davemgreen wrote:

This looks like it should be Arm.cpp, as it is the common code between the Arm and AArch64 backends.

https://github.com/llvm/llvm-project/pull/132252