support normalize function in WSCG

native-sql-engine/cpp/src/codegen/arrow_compute/ext/expression_codegen_visitor.cc

@@ -802,6 +802,27 @@ arrow::Status ExpressionCodegenVisitor::Visit(const gandiva::FunctionNode& node)
     }
     prepare_str_ += prepare_ss.str();
     check_str_ = validity;
+  } else if (func_name.compare("normalize") == 0) {
+    codes_str_ = "normalize_" + std::to_string(cur_func_id);
+    auto validity = codes_str_ + "_validity";
+    std::stringstream fix_ss;
+    fix_ss << "normalize_nan_zero(" << child_visitor_list[0]->GetResult() << ")";
+    std::stringstream prepare_ss;
+    prepare_ss << GetCTypeString(node.return_type()) << " " << codes_str_ << ";"
+               << std::endl;
+    prepare_ss << "bool " << validity << " = " << child_visitor_list[0]->GetPreCheck()
+               << ";" << std::endl;
+    prepare_ss << "if (" << validity << ") {" << std::endl;
+    prepare_ss << codes_str_ << " = (" << GetCTypeString(node.return_type()) << ")"
+               << fix_ss.str() << ";" << std::endl;
+    prepare_ss << "}" << std::endl;
+
+    for (int i = 0; i < 1; i++) {
+      prepare_str_ += child_visitor_list[i]->GetPrepare();
+    }
+    prepare_str_ += prepare_ss.str();
+    check_str_ = validity;
+    header_list_.push_back(R"(#include "precompile/gandiva.h")");
   } else {
     return arrow::Status::NotImplemented(func_name, " is currently not supported.");
   }

native-sql-engine/cpp/src/precompile/gandiva.h

@@ -198,6 +198,16 @@ bool equal_with_nan(double left, double right) {
   return left == right;
 }
 
+double normalize_nan_zero(double in) {
+  if (std::isnan(in)) {
+    return 0.0 / 0.0;
+  } else if (in < 0 && std::abs(in) < 0.0000001) {
+    return 0.0;
+  } else {
+    return in;
+  }
+}
+
 arrow::Decimal128 round(arrow::Decimal128 in, int32_t original_precision,
                         int32_t original_scale, bool* overflow_, int32_t res_scale = 2) {
   bool overflow = false;