[llvm] [GISEL] Add G_VSCALE instruction (PR #84542)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,16 @@
+# RUN: not --crash llc -verify-machineinstrs -run-pass none -o /dev/null %s 2>&1 | FileCheck %s
+# REQUIRES: aarch64-registered-target
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arsenm wrote:

The target isn't specified here, and this doesn't need one as written 

https://github.com/llvm/llvm-project/pull/84542