[DebugInfo][InstrRef][MIR][GlobalIsel][MachineLICM] NFC Use std::move to avoid copying (#116935)

Author: abhishek-kaushik22

llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp

@@ -537,7 +537,7 @@ void GISelKnownBits::computeKnownBitsImpl(Register R, KnownBits &Known,
     computeKnownBitsImpl(SrcReg, SrcOpKnown, SubDemandedElts, Depth + 1);
 
     if (SrcTy.isVector())
-      Known = SrcOpKnown;
+      Known = std::move(SrcOpKnown);
     else
       Known = SrcOpKnown.extractBits(BitWidth, BitWidth * DstIdx);
     break;

llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.cpp

@@ -2927,7 +2927,7 @@ std::optional<ValueIDNum> InstrRefBasedLDV::pickOperandPHILoc(
     SmallVector<LocIdx, 4> NewCandidates;
     std::set_intersection(CandidateLocs.begin(), CandidateLocs.end(),
                           LocVec.begin(), LocVec.end(), std::inserter(NewCandidates, NewCandidates.begin()));
-    CandidateLocs = NewCandidates;
+    CandidateLocs = std::move(NewCandidates);
   }
   if (CandidateLocs.empty())
     return std::nullopt;

llvm/lib/CodeGen/MIRPrinter.cpp

@@ -345,7 +345,7 @@ void MIRPrinter::convert(yaml::MachineFunction &YamlMF,
     if (PreferredReg)
       printRegMIR(PreferredReg, VReg.PreferredRegister, TRI);
     printRegFlags(Reg, VReg.RegisterFlags, MF, TRI);
-    YamlMF.VirtualRegisters.push_back(VReg);
+    YamlMF.VirtualRegisters.push_back(std::move(VReg));
   }
 
   // Print the live ins.
@@ -354,7 +354,7 @@ void MIRPrinter::convert(yaml::MachineFunction &YamlMF,
     printRegMIR(LI.first, LiveIn.Register, TRI);
     if (LI.second)
       printRegMIR(LI.second, LiveIn.VirtualRegister, TRI);
-    YamlMF.LiveIns.push_back(LiveIn);
+    YamlMF.LiveIns.push_back(std::move(LiveIn));
   }
 
   // Prints the callee saved registers.
@@ -364,9 +364,9 @@ void MIRPrinter::convert(yaml::MachineFunction &YamlMF,
     for (const MCPhysReg *I = CalleeSavedRegs; *I; ++I) {
       yaml::FlowStringValue Reg;
       printRegMIR(*I, Reg, TRI);
-      CalleeSavedRegisters.push_back(Reg);
+      CalleeSavedRegisters.push_back(std::move(Reg));
     }
-    YamlMF.CalleeSavedRegisters = CalleeSavedRegisters;
+    YamlMF.CalleeSavedRegisters = std::move(CalleeSavedRegisters);
   }
 }
 

llvm/lib/CodeGen/MachineLICM.cpp

@@ -151,7 +151,7 @@ namespace {
       if (Inserted) {
         SmallVector<MachineBasicBlock *, 8> ExitBlocks;
         CurLoop->getExitBlocks(ExitBlocks);
-        It->second = ExitBlocks;
+        It->second = std::move(ExitBlocks);
       }
       return is_contained(It->second, MBB);
     }