[arm64][turbofan] Fix add+shr for big shift values.

test/cctest/compiler/test-run-machops.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 <cmath>
 #include <functional>
 #include <limits>
 
 #include "src/base/bits.h"
 #include "src/base/ieee754.h"
@@ skipping 6691 matching lines @@
   r.Goto(&merge);
   r.Bind(&flabel);
   Node* fb = r.Int32Constant(0);
   r.Goto(&merge);
   r.Bind(&merge);
   Node* phi = r.Phi(MachineRepresentation::kWord32, fa, fb);
   r.Return(phi);
   CHECK_EQ(1, r.Call(1));
 }
 
+#if V8_TARGET_ARCH_64_BIT
+
+TEST(Regression5923) {
+  {
+    BufferedRawMachineAssemblerTester<int64_t> m(MachineType::Int64());
+    m.Return(m.Int64Add(
+        m.Word64Shr(m.Parameter(0), m.Int64Constant(4611686018427387888)),
+        m.Parameter(0)));
+    m.Call(16l);
+  }
+  {
+    BufferedRawMachineAssemblerTester<int64_t> m(MachineType::Int64());
+    m.Return(m.Int64Add(
+        m.Parameter(0),
+        m.Word64Shr(m.Parameter(0), m.Int64Constant(4611686018427387888))));
+    m.Call(16l);
+  }
+}
+
+#endif  // V8_TARGET_ARCH_64_BIT
+
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8