[turbofan] Add Int64(Add|Sub)WithOverflow support.

src/compiler/x64/instruction-selector-x64.cc

Index: src/compiler/x64/instruction-selector-x64.cc
diff --git a/src/compiler/x64/instruction-selector-x64.cc b/src/compiler/x64/instruction-selector-x64.cc
index b1e1548c17e8ab1d86fa3e3fd545f8ecd63bdacc..2c1c47c6f07a273d16bf6b83604a423f8d19a52d 100644
--- a/src/compiler/x64/instruction-selector-x64.cc
+++ b/src/compiler/x64/instruction-selector-x64.cc
@@ -651,6 +651,16 @@ void InstructionSelector::VisitInt64Add(Node* node) {
 }
 
 
+void InstructionSelector::VisitInt64AddWithOverflow(Node* node) {
+  if (Node* ovf = NodeProperties::FindProjection(node, 1)) {
+    FlagsContinuation cont(kOverflow, ovf);
+    VisitBinop(this, node, kX64Add, &cont);
+  }
+  FlagsContinuation cont;
+  VisitBinop(this, node, kX64Add, &cont);
+}
+
+
 void InstructionSelector::VisitInt32Sub(Node* node) {
   X64OperandGenerator g(this);
   Int32BinopMatcher m(node);
@@ -681,6 +691,16 @@ void InstructionSelector::VisitInt64Sub(Node* node) {
 }
 
 
+void InstructionSelector::VisitInt64SubWithOverflow(Node* node) {
+  if (Node* ovf = NodeProperties::FindProjection(node, 1)) {
+    FlagsContinuation cont(kOverflow, ovf);
+    return VisitBinop(this, node, kX64Sub, &cont);
+  }
+  FlagsContinuation cont;
+  VisitBinop(this, node, kX64Sub, &cont);
+}
+
+
 namespace {
 
 void VisitMul(InstructionSelector* selector, Node* node, ArchOpcode opcode) {
@@ -1493,6 +1513,12 @@ void InstructionSelector::VisitBranch(Node* branch, BasicBlock* tbranch,
               case IrOpcode::kInt32SubWithOverflow:
                 cont.OverwriteAndNegateIfEqual(kOverflow);
                 return VisitBinop(this, node, kX64Sub32, &cont);
+              case IrOpcode::kInt64AddWithOverflow:
+                cont.OverwriteAndNegateIfEqual(kOverflow);
+                return VisitBinop(this, node, kX64Add, &cont);
+              case IrOpcode::kInt64SubWithOverflow:
+                cont.OverwriteAndNegateIfEqual(kOverflow);
+                return VisitBinop(this, node, kX64Sub, &cont);
               default:
                 break;
             }