[llvm] Scalarize binop of splats build vector/free (PR #65773)

[Matt Arsenault via llvm-commits]

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@@ -634,14 +637,15 @@ define <4 x i16> @vec_16xi16_extract_4xi16(ptr addrspace(1) %p0, ptr addrspace(1
 ; GFX9-NEXT:    ; kill: killed $vgpr0 killed $vgpr1
 ; GFX9-NEXT:  .LBB3_4: ; %exit
 ; GFX9-NEXT:    s_waitcnt vmcnt(0)
-; GFX9-NEXT:    v_pk_ashrrev_i16 v0, 15, v5 op_sel_hi:[0,0]
-; GFX9-NEXT:    s_movk_i32 s4, 0x8000
+; GFX9-NEXT:    v_ashrrev_i16_e32 v0, 15, v5
+; GFX9-NEXT:    s_mov_b32 s4, 0x5040100
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arsenm wrote:

More regression 

https://github.com/llvm/llvm-project/pull/65773