[llvm] [AArch64] If-convert diamonds merging a 128-bit vector (PR #220616)

[Guy David via llvm-commits]

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@@ -0,0 +1,402 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -O3 -mtriple=aarch64 -verify-machineinstrs < %s | FileCheck %s
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guy-david wrote:

Fixed up a few into the first commit so it would be clearer what the subsequent commits have updated.

https://github.com/llvm/llvm-project/pull/220616