[Atomics] Remove Atomics code stubs; use TF ops

src/compiler/machine-operator.cc

Index: src/compiler/machine-operator.cc
diff --git a/src/compiler/machine-operator.cc b/src/compiler/machine-operator.cc
index 6a506d26ad334c493ec8c92184eb1bf28b12d0cd..f957902bc51c8ac0184836e72dc43f2a16430e0d 100644
--- a/src/compiler/machine-operator.cc
+++ b/src/compiler/machine-operator.cc
@@ -69,7 +69,8 @@ std::ostream& operator<<(std::ostream& os, StoreRepresentation rep) {
 
 
 LoadRepresentation LoadRepresentationOf(Operator const* op) {
-  DCHECK_EQ(IrOpcode::kLoad, op->opcode());
+  DCHECK(IrOpcode::kLoad == op->opcode() ||
+         IrOpcode::kAtomicLoad == op->opcode());
   return OpParameter<LoadRepresentation>(op);
 }
 
@@ -250,6 +251,14 @@ MachineRepresentation StackSlotRepresentationOf(Operator const* op) {
   V(kWord64)                           \
   V(kTagged)
 
+#define ATOMIC_TYPE_LIST(V) \
+  V(Int8)                   \
+  V(Uint8)                  \
+  V(Int16)                  \
+  V(Uint16)                 \
+  V(Int32)                  \
+  V(Uint32)
+
 struct MachineOperatorGlobalCache {
 #define PURE(Name, properties, value_input_count, control_input_count,         \
              output_count)                                                     \
@@ -353,6 +362,18 @@ struct MachineOperatorGlobalCache {
   CheckedStore##Type##Operator kCheckedStore##Type;
   MACHINE_REPRESENTATION_LIST(STORE)
 #undef STORE
+
+#define ATOMIC(Type)                                                          \
+  struct AtomicLoad##Type##Operator final                                     \
+      : public Operator1<LoadRepresentation> {                                \
+    AtomicLoad##Type##Operator()                                              \
+        : Operator1<LoadRepresentation>(                                      \
+              IrOpcode::kAtomicLoad, Operator::kNoThrow | Operator::kNoWrite, \
+              "AtomicLoad", 2, 1, 1, 1, 1, 0, MachineType::Type()) {}         \
+  };                                                                          \
+  AtomicLoad##Type##Operator kAtomicLoad##Type;
+  ATOMIC_TYPE_LIST(ATOMIC)
+#undef ATOMIC
 };
 
 
@@ -487,6 +508,18 @@ const Operator* MachineOperatorBuilder::Word64PopcntPlaceholder() {
 const Operator* MachineOperatorBuilder::Word64CtzPlaceholder() {
   return &cache_.kWord64Ctz;
 }
+
+const Operator* MachineOperatorBuilder::AtomicLoad(LoadRepresentation rep) {
+#define LOAD(Type)                    \
+  if (rep == MachineType::Type()) {   \
+    return &cache_.kAtomicLoad##Type; \
+  }
+  ATOMIC_TYPE_LIST(LOAD)
+#undef LOAD
+  UNREACHABLE();
+  return nullptr;
+}
+
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8