[Atomics] code stubs for atomic operations

src/compiler/code-stub-assembler.cc

Index: src/compiler/code-stub-assembler.cc
diff --git a/src/compiler/code-stub-assembler.cc b/src/compiler/code-stub-assembler.cc
index f50fa1a14ba028d63fd90f25ee302bbbe380a8eb..8ae2bb174c69bc2b4c97b4fa2b197dc357865bab 100644
--- a/src/compiler/code-stub-assembler.cc
+++ b/src/compiler/code-stub-assembler.cc
@@ -921,6 +921,11 @@ Node* CodeStubAssembler::TruncateTaggedToWord32(Node* context, Node* value) {
   return var_result.value();
 }
 
+Node* CodeStubAssembler::TruncateFloat64ToInt32(Node* value) {
+  return raw_assembler_->TruncateFloat64ToInt32(TruncationMode::kJavaScript,
+                                                value);
+}
+
 void CodeStubAssembler::BranchIf(Node* condition, Label* if_true,
                                  Label* if_false) {
   Label if_condition_is_true(this), if_condition_is_false(this);