[RISCV] Use emplace_back instead of push_back+make_pair. NFC (#148711)

Author: topperc

llvm/lib/Target/RISCV/RISCVOptWInstrs.cpp

@@ -123,7 +123,7 @@ static bool hasAllNBitUsers(const MachineInstr &OrigMI,
   SmallSet<std::pair<const MachineInstr *, unsigned>, 4> Visited;
   SmallVector<std::pair<const MachineInstr *, unsigned>, 4> Worklist;
 
-  Worklist.push_back(std::make_pair(&OrigMI, OrigBits));
+  Worklist.emplace_back(&OrigMI, OrigBits);
 
   while (!Worklist.empty()) {
     auto P = Worklist.pop_back_val();
@@ -213,7 +213,7 @@ static bool hasAllNBitUsers(const MachineInstr &OrigMI,
         // as an N-Bit user.
         unsigned ShAmt = UserMI->getOperand(2).getImm();
         if (Bits > ShAmt) {
-          Worklist.push_back(std::make_pair(UserMI, Bits - ShAmt));
+          Worklist.emplace_back(UserMI, Bits - ShAmt);
           break;
         }
         return false;
@@ -225,29 +225,29 @@ static bool hasAllNBitUsers(const MachineInstr &OrigMI,
         unsigned ShAmt = UserMI->getOperand(2).getImm();
         if (Bits >= (ST.getXLen() - ShAmt))
           break;
-        Worklist.push_back(std::make_pair(UserMI, Bits + ShAmt));
+        Worklist.emplace_back(UserMI, Bits + ShAmt);
         break;
       }
       case RISCV::SLLIW: {
         unsigned ShAmt = UserMI->getOperand(2).getImm();
         if (Bits >= 32 - ShAmt)
           break;
-        Worklist.push_back(std::make_pair(UserMI, Bits + ShAmt));
+        Worklist.emplace_back(UserMI, Bits + ShAmt);
         break;
       }
 
       case RISCV::ANDI: {
         uint64_t Imm = UserMI->getOperand(2).getImm();
         if (Bits >= (unsigned)llvm::bit_width(Imm))
           break;
-        Worklist.push_back(std::make_pair(UserMI, Bits));
+        Worklist.emplace_back(UserMI, Bits);
         break;
       }
       case RISCV::ORI: {
         uint64_t Imm = UserMI->getOperand(2).getImm();
         if (Bits >= (unsigned)llvm::bit_width<uint64_t>(~Imm))
           break;
-        Worklist.push_back(std::make_pair(UserMI, Bits));
+        Worklist.emplace_back(UserMI, Bits);
         break;
       }
 
@@ -261,7 +261,7 @@ static bool hasAllNBitUsers(const MachineInstr &OrigMI,
             break;
           return false;
         }
-        Worklist.push_back(std::make_pair(UserMI, Bits));
+        Worklist.emplace_back(UserMI, Bits);
         break;
 
       case RISCV::SRA:
@@ -280,7 +280,7 @@ static bool hasAllNBitUsers(const MachineInstr &OrigMI,
         // Operand 1 is implicitly zero extended.
         if (OpIdx == 1 && Bits >= 32)
           break;
-        Worklist.push_back(std::make_pair(UserMI, Bits));
+        Worklist.emplace_back(UserMI, Bits);
         break;
 
       case RISCV::BEXTI:
@@ -328,13 +328,13 @@ static bool hasAllNBitUsers(const MachineInstr &OrigMI,
       case RISCV::BSETI:
       case RISCV::BCLRI:
       case RISCV::BINVI:
-        Worklist.push_back(std::make_pair(UserMI, Bits));
+        Worklist.emplace_back(UserMI, Bits);
         break;
 
       case RISCV::BREV8:
       case RISCV::ORC_B:
         // BREV8 and ORC_B work on bytes. Round Bits down to the nearest byte.
-        Worklist.push_back(std::make_pair(UserMI, alignDown(Bits, 8)));
+        Worklist.emplace_back(UserMI, alignDown(Bits, 8));
         break;
 
       case RISCV::PseudoCCMOVGPR:
@@ -344,7 +344,7 @@ static bool hasAllNBitUsers(const MachineInstr &OrigMI,
         // of operand 4 and 5 is used.
         if (OpIdx != 4 && OpIdx != 5)
           return false;
-        Worklist.push_back(std::make_pair(UserMI, Bits));
+        Worklist.emplace_back(UserMI, Bits);
         break;
 
       case RISCV::CZERO_EQZ:
@@ -353,7 +353,7 @@ static bool hasAllNBitUsers(const MachineInstr &OrigMI,
       case RISCV::VT_MASKCN:
         if (OpIdx != 1)
           return false;
-        Worklist.push_back(std::make_pair(UserMI, Bits));
+        Worklist.emplace_back(UserMI, Bits);
         break;
       }
     }