[llvm] [AMDGPU][True16] si-fold-operand selecting srcidx for v_mov_b16_t16_e64 (PR #162101)

[Brox Chen via llvm-commits]

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@@ -932,7 +932,8 @@ static MachineOperand *lookUpCopyChain(const SIInstrInfo &TII,
   for (MachineInstr *SubDef = MRI.getVRegDef(SrcReg);
        SubDef && TII.isFoldableCopy(*SubDef);
        SubDef = MRI.getVRegDef(Sub->getReg())) {
-    unsigned SrcIdx = TII.getFoldableCopySrcIdx(*SubDef);
+    const int SrcIdx =
+        (SubDef->getOpcode()) == AMDGPU::V_MOV_B16_t16_e64 ? 2 : 1;
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broxigarchen wrote:

done

https://github.com/llvm/llvm-project/pull/162101