[llvm] [AArch64] Define constructive EXT_ZZZI pseudo instruction (PR #152552)

[Gaëtan Bossu via llvm-commits]

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@@ -0,0 +1,95 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -mtriple=aarch64 -mattr=+sve -run-pass=aarch64-expand-pseudo -verify-machineinstrs %s -o - | FileCheck %s
+
+# Test the expansion of constructive binary operations into their
+# destructive counterparts.
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gbossu wrote:

Note these aren't new instructions, but there are no MIR test for those "constructive pseudos", only end-to-end .ll tests. So I thought I would add a couple test cases for existing instructions to show the current behaviour, especially around implicit operands.

https://github.com/llvm/llvm-project/pull/152552