[llvm] [AMDGPU] Emit b32 movs if (a)v_mov_b64_pseudo dest vgprs are misaligned (PR #160547)

[Janek van Oirschot via llvm-commits]

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@@ -208,3 +208,23 @@ body: |
     ; CHECK-NEXT: $vgpr2 = V_MOV_B32_e32 -16, implicit $exec, implicit-def $vgpr1_vgpr2
     $vgpr1_vgpr2 = AV_MOV_B64_IMM_PSEUDO 18446744004990074889, implicit $exec
 ...
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JanekvO wrote:

In the case of gfx942 (and without the changes of this PR) my added test for vgpr5_vgpr6 seems to emit a misaligned `v_mov_b64` (https://godbolt.org/z/ch9qcWc3s)

https://github.com/llvm/llvm-project/pull/160547