[llvm] [AMDGPU][True16][CodeGen] S_PACK_XX_B32_B16 lowering for true16 mode (PR #162389)

[Brox Chen via llvm-commits]

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@@ -9084,6 +9115,63 @@ void SIInstrInfo::movePackToVALU(SIInstrWorklist &Worklist,
   MachineOperand &Src1 = Inst.getOperand(2);
   const DebugLoc &DL = Inst.getDebugLoc();
 
+  if (ST.useRealTrue16Insts()) {
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broxigarchen wrote:

yeah we already have a test for it here [fix-sgpr-copies-f16-true16.mir](https://github.com/llvm/llvm-project/pull/162389/files#diff-977d95c3f9cdc3cdc355bebaea7419fe196317fda4b3b0053183258f3d9982be)

https://github.com/llvm/llvm-project/pull/162389