add test

Author: optimisan

llvm/test/CodeGen/AMDGPU/vopd-combine.mir

@@ -4,6 +4,8 @@
 # RUN: llc -mtriple=amdgcn -mcpu=gfx1200 -verify-machineinstrs -run-pass=postmisched %s -o - | FileCheck -check-prefix=SCHED %s
 # RUN: llc -mtriple=amdgcn -mcpu=gfx1200 -verify-machineinstrs -run-pass=postmisched,gcn-create-vopd %s -o - | FileCheck -check-prefixes=PAIR,PAIR-GFX12 %s
 
+# RUN: llc -mtriple=amdgcn -mcpu=gfx1200 -passes=postmisched,gcn-create-vopd %s -o - | FileCheck -check-prefixes=PAIR,PAIR-GFX12 %s
+
 --- |
   @lds = external addrspace(3) global [8 x i8]
   define void @vopd_schedule() { ret void }