[Atomics] Make Atomics.exchange a builtin using TF

src/compiler/mips/instruction-selector-mips.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/base/adapters.h"
 #include "src/base/bits.h"
 #include "src/compiler/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties.h"
 
@@ skipping 1867 matching lines @@
   } else {
     InstructionOperand addr_reg = g.TempRegister();
     Emit(kMipsAdd | AddressingModeField::encode(kMode_None), addr_reg,
          g.UseRegister(index), g.UseRegister(base));
     // Emit desired store opcode, using temp addr_reg.
     Emit(opcode | AddressingModeField::encode(kMode_MRI), g.NoOutput(),
          addr_reg, g.TempImmediate(0), g.UseRegisterOrImmediateZero(value));
   }
 }
 
+void InstructionSelector::VisitAtomicExchange(Node* node) { UNIMPLEMENTED(); }
+
 // static
 MachineOperatorBuilder::Flags
 InstructionSelector::SupportedMachineOperatorFlags() {
   MachineOperatorBuilder::Flags flags = MachineOperatorBuilder::kNoFlags;
   if ((IsMipsArchVariant(kMips32r2) || IsMipsArchVariant(kMips32r6)) &&
       IsFp64Mode()) {
     flags |= MachineOperatorBuilder::kFloat64RoundDown |
              MachineOperatorBuilder::kFloat64RoundUp |
              MachineOperatorBuilder::kFloat64RoundTruncate |
              MachineOperatorBuilder::kFloat64RoundTiesEven;
@@ skipping 22 matching lines @@
     DCHECK(IsMipsArchVariant(kLoongson) || IsMipsArchVariant(kMips32r1) ||
            IsMipsArchVariant(kMips32r2));
     return MachineOperatorBuilder::AlignmentRequirements::
         NoUnalignedAccessSupport();
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8