[llvm] [AMDGPU] Support Wave Reduction for i16 types - 1 (PR #194808)

[Matt Arsenault via llvm-commits]

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@@ -5628,6 +5627,22 @@ static void expand64BitV_CNDMASK(MachineInstr &MI, MachineBasicBlock *BB) {
 
 static uint64_t getIdentityValueForWaveReduction(unsigned Opc) {
   switch (Opc) {
+  case AMDGPU::V_MIN_U16_e64:
+  case AMDGPU::V_MIN_U16_opsel_e64:
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arsenm wrote:

Are the _opsel cases actually reachable? 

https://github.com/llvm/llvm-project/pull/194808