Fix logical right shift operator for signed negative integers

Signed-off-by: Won Jeon <won.jeon@arm.com>
Change-Id: Id37100ba8bc2ac64b1f54788c6f765fedfab0816
diff --git a/reference_model/src/ops/ewise_binary.cc b/reference_model/src/ops/ewise_binary.cc
index e1713a0..22ace95 100644
--- a/reference_model/src/ops/ewise_binary.cc
+++ b/reference_model/src/ops/ewise_binary.cc
@@ -1,5 +1,5 @@
 
-// Copyright (c) 2020-2023, ARM Limited.
+// Copyright (c) 2020-2024, ARM Limited.
 //
 //    Licensed under the Apache License, Version 2.0 (the "License");
 //    you may not use this file except in compliance with the License.
@@ -348,21 +348,21 @@
             this->fcn = [this](InEigenType a, InEigenType b) -> OutEigenType {
                 REQUIRE(b >= 0 && b <= 31, "OpLogicalRightShift: shift value %d is out of valid range [0, 31]",
                         (int32_t)b);
-                return static_cast<OutEigenType>(static_cast<int8_t>(a) >> b);
+                return static_cast<OutEigenType>(static_cast<int8_t>(static_cast<uint8_t>(a) >> b));
             };
             break;
         case TOSA_REF_TYPE_INT16:
             this->fcn = [this](InEigenType a, InEigenType b) -> OutEigenType {
                 REQUIRE(b >= 0 && b <= 31, "OpLogicalRightShift: shift value %d is out of valid range [0, 31]",
                         (int32_t)b);
-                return static_cast<OutEigenType>(static_cast<int16_t>(a) >> b);
+                return static_cast<OutEigenType>(static_cast<int16_t>(static_cast<uint16_t>(a) >> b));
             };
             break;
         case TOSA_REF_TYPE_INT32:
             this->fcn = [this](InEigenType a, InEigenType b) -> OutEigenType {
                 REQUIRE(b >= 0 && b <= 31, "OpLogicalRightShift: shift value %d is out of valid range [0, 31]",
                         (int32_t)b);
-                return static_cast<OutEigenType>(static_cast<int32_t>(a) >> b);
+                return static_cast<OutEigenType>(static_cast<int32_t>(static_cast<uint32_t>(a) >> b));
             };
             break;
         default: