[llvm] [True16] Make loads into s16 legal in GlobalISel (PR #176963)

[Domenic Nutile via llvm-commits]

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@@ -662,10 +668,16 @@ define half @test_vector_reduce_fminimum_v8half(<8 x half> %v) {
 ; GFX12-GISEL-TRUE16-NEXT:    s_wait_samplecnt 0x0
 ; GFX12-GISEL-TRUE16-NEXT:    s_wait_bvhcnt 0x0
 ; GFX12-GISEL-TRUE16-NEXT:    s_wait_kmcnt 0x0
-; GFX12-GISEL-TRUE16-NEXT:    v_minimum_f16 v0.l, v0.l, v0.h
-; GFX12-GISEL-TRUE16-NEXT:    v_minimum_f16 v0.h, v1.l, v1.h
-; GFX12-GISEL-TRUE16-NEXT:    v_minimum_f16 v1.l, v2.l, v2.h
-; GFX12-GISEL-TRUE16-NEXT:    v_minimum_f16 v1.h, v3.l, v3.h
+; GFX12-GISEL-TRUE16-NEXT:    v_lshrrev_b32_e32 v4, 16, v0
+; GFX12-GISEL-TRUE16-NEXT:    v_lshrrev_b32_e32 v5, 16, v1
+; GFX12-GISEL-TRUE16-NEXT:    v_lshrrev_b32_e32 v6, 16, v2
+; GFX12-GISEL-TRUE16-NEXT:    v_lshrrev_b32_e32 v7, 16, v3
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saxlungs wrote:

I'm going to resolve this because this change is no longer in the PR due to removing the G_MERGE/UNMERGE_VALUES changes. However, I will be keeping an eye on this after this PR and Petar's PR go in to make sure nothing like this pops up in the tests again

https://github.com/llvm/llvm-project/pull/176963