[llvm] [AMDGPU] Add MachineVerifer check to detect illegal copies from VGPR to SGPR (PR #105494)

[Christudasan Devadasan via llvm-commits]

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@@ -32,38 +32,6 @@ body:             |
     S_BRANCH %bb.2
 ...
 
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-# GCN-LABEL: name: phi_moveimm_subreg_input
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cdevadas wrote:

This test doesn't look legitimate to be invoked by a pass that needs SSA from. The presence of the subreg def makes this test a non-SSA one.

https://github.com/llvm/llvm-project/pull/105494