LLVM: Use zero extension for unsigned int cast

Author: ubaidsk

src/libasr/codegen/asr_to_llvm.cpp

@@ -6025,8 +6025,7 @@ class ASRToLLVMVisitor : public ASR::BaseVisitor<ASRToLLVMVisitor>
                 }
                 break;
             }
-            case (ASR::cast_kindType::IntegerToInteger) :
-            case (ASR::cast_kindType::UnsignedIntegerToUnsignedInteger) : {
+            case (ASR::cast_kindType::IntegerToInteger) : {
                 int arg_kind = -1, dest_kind = -1;
                 extract_kinds(x, arg_kind, dest_kind);
                 if( arg_kind > 0 && dest_kind > 0 &&
@@ -6040,6 +6039,20 @@ class ASRToLLVMVisitor : public ASR::BaseVisitor<ASRToLLVMVisitor>
                 }
                 break;
             }
+            case (ASR::cast_kindType::UnsignedIntegerToUnsignedInteger) : {
+                int arg_kind = -1, dest_kind = -1;
+                extract_kinds(x, arg_kind, dest_kind);
+                if( arg_kind > 0 && dest_kind > 0 &&
+                    arg_kind != dest_kind )
+                {
+                    if (dest_kind > arg_kind) {
+                        tmp = builder->CreateZExt(tmp, llvm_utils->getIntType(dest_kind));
+                    } else {
+                        tmp = builder->CreateTrunc(tmp, llvm_utils->getIntType(dest_kind));
+                    }
+                }
+                break;
+            }
             case (ASR::cast_kindType::IntegerToUnsignedInteger) : {
                 int arg_kind = -1, dest_kind = -1;
                 extract_kinds(x, arg_kind, dest_kind);