refactor(codegen): null safe for struct ir builder

cases/query/const_query.yaml

@@ -126,15 +126,55 @@ cases:
       columns: ['c1 bool', 'c2 int16', 'c3 int', 'c4 double', 'c5 string', 'c6 date', 'c7 timestamp' ]
       rows:
         - [ true, 3, 13, 10.0, 'a string', '2020-05-22', 1590115420000 ]
+
+  # =================================================================================
+  # Null safe for structure types: String, Date, Timestamp and Array
+  # creating struct from:
+  # 1. NULL liternal (const null)
+  # 2. another supported date type but fails to cast, e.g. timestamp(-1) returns NULL of timestamp
+  #
+  # casting to array type un-implemented
+  # =================================================================================
   - id: 10
+    desc: null safe for date
     mode: procedure-unsupport
     sql: |
       select
         datediff(Date(timestamp(-1)), Date("2021-05-01")) as out1,
         datediff(Date(timestamp(-2177481600)), Date("2021-05-01")) as out2,
-        datediff(cast(NULL as date), Date("2021-05-01")) as out3
-        ;
+        datediff(cast(NULL as date), Date("2021-05-01")) as out3,
+        date(NULL) as out4,
+        date("abc") as out5,
+        date(timestamp("abc")) as out6
+    expect:
+      columns: ["out1 int", "out2 int", "out3 int", "out4 date", "out5 date", "out6 date"]
+      data: |
+        NULL, NULL, NULL, NULL, NULL, NULL
+  - id: 11
+    desc: null safe for timestamp
+    mode: procedure-unsupport
+    sql: |
+      select
+        month(cast(NULL as timestamp)) as out1,
+        month(timestamp(NULL)) as out2,
+        month(timestamp(-1)) as out3,
+        month(timestamp("abc")) as out4,
+        month(timestamp(date("abc"))) as out5
+    expect:
+      columns: ["out1 int", "out2 int", "out3 int", "out4 int", "out5 int"]
+      data: |
+        NULL, NULL, NULL, NULL, NULL
+  - id: 12
+    desc: null safe for string
+    mode: procedure-unsupport
+    sql: |
+      select
+        char_length(cast(NULL as string)) as out1,
+        char_length(string(int(NULL))) as out2,
+        char_length(string(bool(null))) as out3,
+        char_length(string(timestamp(null))) as out4,
+        char_length(string(date(null))) as out5
     expect:
-      columns: ["out1 int", "out2 int", "out3 int"]
+      columns: ["out1 int", "out2 int", "out3 int", "out4 int", "out5 int"]
       data: |
-        NULL, NULL, NULL
+        NULL, NULL, NULL, NULL, NULL

hybridse/src/codegen/array_ir_builder.cc

@@ -114,5 +114,21 @@
     return base::Status::OK();
 }
 
+bool ArrayIRBuilder::CreateDefault(::llvm::BasicBlock* block, ::llvm::Value** output) {
+    llvm::Value* array_alloca = nullptr;
+    if (!Create(block, &array_alloca)) {
+        return false;
+    }
+
+    llvm::IRBuilder<> builder(block);
+    ::llvm::Value* array_sz = builder.getInt64(0);
+    if (!Set(block, array_alloca, 2, array_sz)) {
+        return false;
+    }
+
+    *output = array_alloca;
+    return true;
+}
+
 }  // namespace codegen
 }  // namespace hybridse

hybridse/src/codegen/array_ir_builder.h

@@ -49,12 +49,12 @@
 
     void InitStructType() override;
 
-    bool CreateDefault(::llvm::BasicBlock* block, ::llvm::Value** output) override { return true; }
+    bool CreateDefault(::llvm::BasicBlock* block, ::llvm::Value** output) override;
 
     bool CopyFrom(::llvm::BasicBlock* block, ::llvm::Value* src, ::llvm::Value* dist) override { return true; }
 
     base::Status CastFrom(::llvm::BasicBlock* block, const NativeValue& src, NativeValue* output) override {
-        return base::Status::OK();
+        CHECK_TRUE(false, common::kCodegenError, "casting to array un-implemented");
     };
 
  private:

hybridse/src/codegen/cast_expr_ir_builder.cc

@@ -15,12 +15,15 @@
  */
 
 #include "codegen/cast_expr_ir_builder.h"
+
 #include "codegen/date_ir_builder.h"
 #include "codegen/ir_base_builder.h"
 #include "codegen/string_ir_builder.h"
 #include "codegen/timestamp_ir_builder.h"
+#include "codegen/type_ir_builder.h"
 #include "glog/logging.h"
 #include "node/node_manager.h"
+#include "proto/fe_common.pb.h"
 
 using hybridse::common::kCodegenError;
 
@@ -72,98 +75,73 @@
     }
     return Status::OK();
 }
-Status CastExprIRBuilder::SafeCast(const NativeValue& value, ::llvm::Type* type,
-                                   NativeValue* output) {
+
+Status CastExprIRBuilder::SafeCast(const NativeValue& value, ::llvm::Type* dst_type, NativeValue* output) {
     ::llvm::IRBuilder<> builder(block_);
-    CHECK_TRUE(IsSafeCast(value.GetType(), type), kCodegenError,
-               "Safe cast fail: unsafe cast");
+    CHECK_TRUE(IsSafeCast(value.GetType(), dst_type), kCodegenError, "Safe cast fail: unsafe cast");
     Status status;
     if (value.IsConstNull()) {
-        if (TypeIRBuilder::IsStringPtr(type)) {
-            StringIRBuilder string_ir_builder(block_->getModule());
-            CHECK_STATUS(string_ir_builder.CreateNull(block_, output));
-            return base::Status::OK();
-        } else {
-            *output = NativeValue::CreateNull(type);
-        }
-    } else if (TypeIRBuilder::IsTimestampPtr(type)) {
+        auto res = CreateSafeNull(block_, dst_type);
+        CHECK_TRUE(res.ok(), kCodegenError, res.status().ToString());
+        *output = res.value();
+    } else if (TypeIRBuilder::IsTimestampPtr(dst_type)) {
         TimestampIRBuilder timestamp_ir_builder(block_->getModule());
         CHECK_STATUS(timestamp_ir_builder.CastFrom(block_, value, output));
         return Status::OK();
-    } else if (TypeIRBuilder::IsDatePtr(type)) {
+    } else if (TypeIRBuilder::IsDatePtr(dst_type)) {
         DateIRBuilder date_ir_builder(block_->getModule());
         CHECK_STATUS(date_ir_builder.CastFrom(block_, value, output));
         return Status::OK();
-    } else if (TypeIRBuilder::IsStringPtr(type)) {
+    } else if (TypeIRBuilder::IsStringPtr(dst_type)) {
         StringIRBuilder string_ir_builder(block_->getModule());
         CHECK_STATUS(string_ir_builder.CastFrom(block_, value, output));
         return Status::OK();
-    } else if (TypeIRBuilder::IsNumber(type)) {
+    } else if (TypeIRBuilder::IsNumber(dst_type)) {
         Status status;
         ::llvm::Value* output_value = nullptr;
-        CHECK_TRUE(SafeCastNumber(value.GetValue(&builder), type, &output_value,
-                                  status),
-                   kCodegenError);
+        CHECK_TRUE(SafeCastNumber(value.GetValue(&builder), dst_type, &output_value, status), kCodegenError);
         if (value.IsNullable()) {
-            *output = NativeValue::CreateWithFlag(output_value,
-                                                  value.GetIsNull(&builder));
+            *output = NativeValue::CreateWithFlag(output_value, value.GetIsNull(&builder));
         } else {
             *output = NativeValue::Create(output_value);
         }
     } else {
-        return Status(common::kCodegenError,
-                      "Can't cast from " +
-                          TypeIRBuilder::TypeName(value.GetType()) + " to " +
-                          TypeIRBuilder::TypeName(type));
+        return Status(common::kCodegenError, "Can't cast from " + TypeIRBuilder::TypeName(value.GetType()) + " to " +
+                                                 TypeIRBuilder::TypeName(dst_type));
     }
     return Status::OK();
 }
-Status CastExprIRBuilder::UnSafeCast(const NativeValue& value,
-                                     ::llvm::Type* type, NativeValue* output) {
-    ::llvm::IRBuilder<> builder(block_);
-    if (value.IsConstNull()) {
-        if (TypeIRBuilder::IsStringPtr(type)) {
-            StringIRBuilder string_ir_builder(block_->getModule());
-            CHECK_STATUS(string_ir_builder.CreateNull(block_, output));
-            return base::Status::OK();
 
-        } else if (TypeIRBuilder::IsDatePtr(type)) {
-            DateIRBuilder date_ir(block_->getModule());
-            CHECK_STATUS(date_ir.CreateNull(block_, output));
-            return base::Status::OK();
-        } else {
-            *output = NativeValue::CreateNull(type);
-        }
-    } else if (TypeIRBuilder::IsTimestampPtr(type)) {
+Status CastExprIRBuilder::UnSafeCast(const NativeValue& value, ::llvm::Type* dst_type, NativeValue* output) {
+    ::llvm::IRBuilder<> builder(block_);
+    if (value.IsConstNull() || (TypeIRBuilder::IsNumber(dst_type) && TypeIRBuilder::IsDatePtr(value.GetType()))) {
+        // input is const null or (cast date to number)
+        auto res = CreateSafeNull(block_, dst_type);
+        CHECK_TRUE(res.ok(), kCodegenError, res.status().ToString());
+        *output = res.value();
+    } else if (TypeIRBuilder::IsTimestampPtr(dst_type)) {
         TimestampIRBuilder timestamp_ir_builder(block_->getModule());
         CHECK_STATUS(timestamp_ir_builder.CastFrom(block_, value, output));
         return Status::OK();
-    } else if (TypeIRBuilder::IsDatePtr(type)) {
+    } else if (TypeIRBuilder::IsDatePtr(dst_type)) {
         DateIRBuilder date_ir_builder(block_->getModule());
         CHECK_STATUS(date_ir_builder.CastFrom(block_, value, output));
         return Status::OK();
-    } else if (TypeIRBuilder::IsStringPtr(type)) {
+    } else if (TypeIRBuilder::IsStringPtr(dst_type)) {
         StringIRBuilder string_ir_builder(block_->getModule());
         CHECK_STATUS(string_ir_builder.CastFrom(block_, value, output));
         return Status::OK();
-    } else if (TypeIRBuilder::IsNumber(type) &&
-               TypeIRBuilder::IsStringPtr(value.GetType())) {
+    } else if (TypeIRBuilder::IsNumber(dst_type) && TypeIRBuilder::IsStringPtr(value.GetType())) {
         StringIRBuilder string_ir_builder(block_->getModule());
-        CHECK_STATUS(
-            string_ir_builder.CastToNumber(block_, value, type, output));
+        CHECK_STATUS(string_ir_builder.CastToNumber(block_, value, dst_type, output));
         return Status::OK();
-    } else if (TypeIRBuilder::IsNumber(type) &&
-               TypeIRBuilder::IsDatePtr(value.GetType())) {
-        *output = NativeValue::CreateNull(type);
     } else {
         Status status;
         ::llvm::Value* output_value = nullptr;
-        CHECK_TRUE(UnSafeCastNumber(value.GetValue(&builder), type,
-                                    &output_value, status),
-                   kCodegenError, status.msg);
+        CHECK_TRUE(UnSafeCastNumber(value.GetValue(&builder), dst_type, &output_value, status), kCodegenError,
+                   status.msg);
         if (value.IsNullable()) {
-            *output = NativeValue::CreateWithFlag(output_value,
-                                                  value.GetIsNull(&builder));
+            *output = NativeValue::CreateWithFlag(output_value, value.GetIsNull(&builder));
         } else {
             *output = NativeValue::Create(output_value);
         }

hybridse/src/codegen/cast_expr_ir_builder.h

@@ -18,9 +18,6 @@
 #define HYBRIDSE_SRC_CODEGEN_CAST_EXPR_IR_BUILDER_H_
 #include "base/fe_status.h"
 #include "codegen/cond_select_ir_builder.h"
-#include "codegen/scope_var.h"
-#include "llvm/IR/IRBuilder.h"
-#include "proto/fe_type.pb.h"
 
 namespace hybridse {
 namespace codegen {
@@ -32,26 +29,19 @@ class CastExprIRBuilder {
     explicit CastExprIRBuilder(::llvm::BasicBlock* block);
     ~CastExprIRBuilder();
 
-    Status Cast(const NativeValue& value, ::llvm::Type* cast_type,
-                NativeValue* output);  // NOLINT
-    Status SafeCast(const NativeValue& value, ::llvm::Type* type,
-                    NativeValue* output);  // NOLINT
-    Status UnSafeCast(const NativeValue& value, ::llvm::Type* type,
-                      NativeValue* output);  // NOLINT
+    Status Cast(const NativeValue& value, ::llvm::Type* cast_type, NativeValue* output);
+    Status SafeCast(const NativeValue& value, ::llvm::Type* dst_type, NativeValue* output);
+    Status UnSafeCast(const NativeValue& value, ::llvm::Type* dst_type, NativeValue* output);
     static bool IsSafeCast(::llvm::Type* lhs, ::llvm::Type* rhs);
-    static Status InferNumberCastTypes(::llvm::Type* left_type,
-                                       ::llvm::Type* right_type);
+    static Status InferNumberCastTypes(::llvm::Type* left_type, ::llvm::Type* right_type);
     static bool IsIntFloat2PointerCast(::llvm::Type* src, ::llvm::Type* dist);
     bool BoolCast(llvm::Value* pValue, llvm::Value** pValue1,
                   base::Status& status);  // NOLINT
-    bool SafeCastNumber(::llvm::Value* value, ::llvm::Type* type,
-                        ::llvm::Value** output,
+    bool SafeCastNumber(::llvm::Value* value, ::llvm::Type* type, ::llvm::Value** output,
                         base::Status& status);  // NOLINT
-    bool UnSafeCastNumber(::llvm::Value* value, ::llvm::Type* type,
-                          ::llvm::Value** output,
+    bool UnSafeCastNumber(::llvm::Value* value, ::llvm::Type* type, ::llvm::Value** output,
                           base::Status& status);  // NOLINT
-    bool UnSafeCastDouble(::llvm::Value* value, ::llvm::Type* type,
-                          ::llvm::Value** output,
+    bool UnSafeCastDouble(::llvm::Value* value, ::llvm::Type* type, ::llvm::Value** output,
                           base::Status& status);  // NOLINT
 
  private:

hybridse/src/codegen/date_ir_builder.cc

@@ -45,14 +45,6 @@ void DateIRBuilder::InitStructType() {
     return;
 }
 
-base::Status DateIRBuilder::CreateNull(::llvm::BasicBlock* block, NativeValue* output) {
-    ::llvm::Value* value = nullptr;
-    CHECK_TRUE(CreateDefault(block, &value), common::kCodegenError, "Fail to construct string")
-    ::llvm::IRBuilder<> builder(block);
-    *output = NativeValue::CreateWithFlag(value, builder.getInt1(true));
-    return base::Status::OK();
-}
-
 bool DateIRBuilder::CreateDefault(::llvm::BasicBlock* block,
                                   ::llvm::Value** output) {
     return NewDate(block, output);

hybridse/src/codegen/date_ir_builder.h

@@ -27,16 +27,14 @@ class DateIRBuilder : public StructTypeIRBuilder {
  public:
     explicit DateIRBuilder(::llvm::Module* m);
     ~DateIRBuilder();
-    void InitStructType() override;
 
-    base::Status CreateNull(::llvm::BasicBlock* block, NativeValue* output);
+    void InitStructType() override;
     bool CreateDefault(::llvm::BasicBlock* block, ::llvm::Value** output) override;
+    bool CopyFrom(::llvm::BasicBlock* block, ::llvm::Value* src, ::llvm::Value* dist) override;
+    base::Status CastFrom(::llvm::BasicBlock* block, const NativeValue& src, NativeValue* output) override;
 
     bool NewDate(::llvm::BasicBlock* block, ::llvm::Value** output);
-    bool NewDate(::llvm::BasicBlock* block, ::llvm::Value* date,
-                 ::llvm::Value** output);
-    bool CopyFrom(::llvm::BasicBlock* block, ::llvm::Value* src, ::llvm::Value* dist);
-    base::Status CastFrom(::llvm::BasicBlock* block, const NativeValue& src, NativeValue* output);
+    bool NewDate(::llvm::BasicBlock* block, ::llvm::Value* date, ::llvm::Value** output);
 
     bool GetDate(::llvm::BasicBlock* block, ::llvm::Value* date,
                  ::llvm::Value** output);

hybridse/src/codegen/expr_ir_builder.cc

@@ -26,10 +26,8 @@
 #include "codegen/cond_select_ir_builder.h"
 #include "codegen/context.h"
 #include "codegen/date_ir_builder.h"
-#include "codegen/fn_ir_builder.h"
 #include "codegen/ir_base_builder.h"
 #include "codegen/list_ir_builder.h"
-#include "codegen/struct_ir_builder.h"
 #include "codegen/timestamp_ir_builder.h"
 #include "codegen/type_ir_builder.h"
 #include "codegen/udf_ir_builder.h"
@@ -217,8 +215,7 @@ Status ExprIRBuilder::BuildConstExpr(
     ::llvm::IRBuilder<> builder(ctx_->GetCurrentBlock());
     switch (const_node->GetDataType()) {
         case ::hybridse::node::kNull: {
-            *output = NativeValue::CreateNull(
-                llvm::Type::getTokenTy(builder.getContext()));
+            *output = NativeValue(nullptr, nullptr, llvm::Type::getTokenTy(builder.getContext()));
             break;
         }
         case ::hybridse::node::kBool: {

hybridse/src/codegen/ir_base_builder.cc

@@ -17,7 +17,6 @@
 #include "codegen/ir_base_builder.h"
 
 #include <string>
-#include <tuple>
 #include <utility>
 #include <vector>
 
@@ -625,21 +624,25 @@
                 return false;
             }
 
-            if (pointee_ty->getStructName().startswith("fe.list_ref_")) {
+            auto struct_name = pointee_ty->getStructName();
+            if (struct_name.startswith("fe.list_ref_")) {
                 *output = hybridse::node::kList;
                 return true;
-            } else if (pointee_ty->getStructName().startswith("fe.iterator_ref_")) {
+            } else if (struct_name.startswith("fe.iterator_ref_")) {
                 *output = hybridse::node::kIterator;
                 return true;
-            } else if (pointee_ty->getStructName().equals("fe.string_ref")) {
+            } else if (struct_name.equals("fe.string_ref")) {
                 *output = hybridse::node::kVarchar;
                 return true;
-            } else if (pointee_ty->getStructName().equals("fe.timestamp")) {
+            } else if (struct_name.equals("fe.timestamp")) {
                 *output = hybridse::node::kTimestamp;
                 return true;
-            } else if (pointee_ty->getStructName().equals("fe.date")) {
+            } else if (struct_name.equals("fe.date")) {
                 *output = hybridse::node::kDate;
                 return true;
+            } else if (struct_name.startswith("fe.array_")) {
+                *output = hybridse::node::kArray;
+                return true;
             }
             LOG(WARNING) << "no mapping pointee_ty for llvm pointee_ty "
                          << pointee_ty->getStructName().str();