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

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,33 @@
+# RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx942 -start-after=si-load-store-opt %s -o - | FileCheck %s
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arsenm wrote:

This is a weird way to write the test. Can you replace this with an end to end IR test that hit this problem 

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