planner: move hash encoding logic and HasMaxOneRow to util (#53161)

ref #51664, ref #52714

pkg/planner/core/hashcode.go

@@ -19,21 +19,16 @@ import (
 	"encoding/binary"
 	"slices"
 
+	"github.com/pingcap/tidb/pkg/planner/util"
 	"github.com/pingcap/tidb/pkg/util/plancodec"
 )
 
-func encodeIntAsUint32(result []byte, value int) []byte {
-	var buf [4]byte
-	binary.BigEndian.PutUint32(buf[:], uint32(value))
-	return append(result, buf[:]...)
-}
-
 // HashCode implements LogicalPlan interface.
 func (p *baseLogicalPlan) HashCode() []byte {
 	// We use PlanID for the default hash, so if two plans do not have
 	// the same id, the hash value will never be the same.
 	result := make([]byte, 0, 4)
-	result = encodeIntAsUint32(result, p.ID())
+	result = util.EncodeIntAsUint32(result, p.ID())
 	return result
 }
 
@@ -43,12 +38,12 @@ func (p *LogicalProjection) HashCode() []byte {
 	// Expressions are commonly `Column`s, whose hashcode has the length 9, so
 	// we pre-alloc 10 bytes for each expr's hashcode.
 	result := make([]byte, 0, 12+len(p.Exprs)*10)
-	result = encodeIntAsUint32(result, plancodec.TypeStringToPhysicalID(p.TP()))
-	result = encodeIntAsUint32(result, p.QueryBlockOffset())
-	result = encodeIntAsUint32(result, len(p.Exprs))
+	result = util.EncodeIntAsUint32(result, plancodec.TypeStringToPhysicalID(p.TP()))
+	result = util.EncodeIntAsUint32(result, p.QueryBlockOffset())
+	result = util.EncodeIntAsUint32(result, len(p.Exprs))
 	for _, expr := range p.Exprs {
 		exprHashCode := expr.HashCode()
-		result = encodeIntAsUint32(result, len(exprHashCode))
+		result = util.EncodeIntAsUint32(result, len(exprHashCode))
 		result = append(result, exprHashCode...)
 	}
 	return result
@@ -58,9 +53,9 @@ func (p *LogicalProjection) HashCode() []byte {
 func (p *LogicalTableDual) HashCode() []byte {
 	// PlanType + SelectOffset + RowCount
 	result := make([]byte, 0, 12)
-	result = encodeIntAsUint32(result, plancodec.TypeStringToPhysicalID(p.TP()))
-	result = encodeIntAsUint32(result, p.QueryBlockOffset())
-	result = encodeIntAsUint32(result, p.RowCount)
+	result = util.EncodeIntAsUint32(result, plancodec.TypeStringToPhysicalID(p.TP()))
+	result = util.EncodeIntAsUint32(result, p.QueryBlockOffset())
+	result = util.EncodeIntAsUint32(result, p.RowCount)
 	return result
 }
 
@@ -70,9 +65,9 @@ func (p *LogicalSelection) HashCode() []byte {
 	// Conditions are commonly `ScalarFunction`s, whose hashcode usually has a
 	// length larger than 20, so we pre-alloc 25 bytes for each expr's hashcode.
 	result := make([]byte, 0, 12+len(p.Conditions)*25)
-	result = encodeIntAsUint32(result, plancodec.TypeStringToPhysicalID(p.TP()))
-	result = encodeIntAsUint32(result, p.QueryBlockOffset())
-	result = encodeIntAsUint32(result, len(p.Conditions))
+	result = util.EncodeIntAsUint32(result, plancodec.TypeStringToPhysicalID(p.TP()))
+	result = util.EncodeIntAsUint32(result, p.QueryBlockOffset())
+	result = util.EncodeIntAsUint32(result, len(p.Conditions))
 
 	condHashCodes := make([][]byte, len(p.Conditions))
 	for i, expr := range p.Conditions {
@@ -82,7 +77,7 @@ func (p *LogicalSelection) HashCode() []byte {
 	slices.SortFunc(condHashCodes, func(i, j []byte) int { return bytes.Compare(i, j) })
 
 	for _, condHashCode := range condHashCodes {
-		result = encodeIntAsUint32(result, len(condHashCode))
+		result = util.EncodeIntAsUint32(result, len(condHashCode))
 		result = append(result, condHashCode...)
 	}
 	return result

pkg/planner/core/plan.go

@@ -34,6 +34,10 @@ import (
 	"github.com/pingcap/tidb/pkg/util/tracing"
 )
 
+func init() {
+	util.HasMaxOneRowUtil = HasMaxOneRow
+}
+
 // AsSctx converts PlanContext to sessionctx.Context.
 func AsSctx(pctx base.PlanContext) (sessionctx.Context, error) {
 	sctx, ok := pctx.(sessionctx.Context)
@@ -475,7 +479,7 @@ func (p *baseLogicalPlan) BuildKeyInfo(_ *expression.Schema, _ []*expression.Sch
 	for i := range p.children {
 		childMaxOneRow[i] = p.children[i].MaxOneRow()
 	}
-	p.maxOneRow = HasMaxOneRow(p.self, childMaxOneRow)
+	p.maxOneRow = util.HasMaxOneRowUtil(p.self, childMaxOneRow)
 }
 
 // BuildKeyInfo implements LogicalPlan BuildKeyInfo interface.

pkg/planner/memo/BUILD.bazel

@@ -16,6 +16,7 @@ go_library(
         "//pkg/planner/core/base",
         "//pkg/planner/pattern",
         "//pkg/planner/property",
+        "//pkg/planner/util",
     ],
 )
 

pkg/planner/memo/group.go

@@ -19,10 +19,12 @@ import (
 	"fmt"
 
 	"github.com/pingcap/tidb/pkg/expression"
-	plannercore "github.com/pingcap/tidb/pkg/planner/core"
+	// import core pkg first to call its init func.
+	_ "github.com/pingcap/tidb/pkg/planner/core"
 	"github.com/pingcap/tidb/pkg/planner/core/base"
 	"github.com/pingcap/tidb/pkg/planner/pattern"
 	"github.com/pingcap/tidb/pkg/planner/property"
+	"github.com/pingcap/tidb/pkg/planner/util"
 )
 
 // ExploreMark is uses to mark whether a Group or GroupExpr has
@@ -221,5 +223,5 @@ func (g *Group) BuildKeyInfo() {
 		g.Prop.Schema.Keys = childSchema[0].Keys
 	}
 	e.ExprNode.BuildKeyInfo(g.Prop.Schema, childSchema)
-	g.Prop.MaxOneRow = e.ExprNode.MaxOneRow() || plannercore.HasMaxOneRow(e.ExprNode, childMaxOneRow)
+	g.Prop.MaxOneRow = e.ExprNode.MaxOneRow() || util.HasMaxOneRowUtil(e.ExprNode, childMaxOneRow)
 }

pkg/planner/util/BUILD.bazel

@@ -5,6 +5,7 @@ go_library(
     srcs = [
         "byitem.go",
         "expression.go",
+        "func_pointer_misc.go",
         "handle_cols.go",
         "misc.go",
         "null_misc.go",
@@ -19,6 +20,7 @@ go_library(
         "//pkg/parser/model",
         "//pkg/parser/mysql",
         "//pkg/planner/context",
+        "//pkg/planner/core/base",
         "//pkg/sessionctx/stmtctx",
         "//pkg/tablecodec",
         "//pkg/types",

pkg/planner/util/func_pointer_misc.go

@@ -0,0 +1,25 @@
+// Copyright 2024 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package util
+
+import "github.com/pingcap/tidb/pkg/planner/core/base"
+
+// this file is used for passing function pointer at init(){} to avoid some import cycles.
+
+// HasMaxOneRowUtil is used in baseLogicalPlan implementation of LogicalPlan interface, while
+// the original HasMaxOneRowUtil has some dependency of original core pkg: like Datasource which
+// hasn't been moved out of core pkg, so associative func pointer is introduced.
+// todo: (1) arenatlx, remove this func pointer when concrete Logical Operators moved out.
+var HasMaxOneRowUtil func(p base.LogicalPlan, childMaxOneRow []bool) bool

pkg/planner/util/misc.go

@@ -15,6 +15,7 @@
 package util
 
 import (
+	"encoding/binary"
 	"fmt"
 	"time"
 	"unsafe"
@@ -88,3 +89,10 @@ func (tr *QueryTimeRange) MemoryUsage() (sum int64) {
 	}
 	return emptyQueryTimeRangeSize
 }
+
+// EncodeIntAsUint32 is used for LogicalPlan Interface
+func EncodeIntAsUint32(result []byte, value int) []byte {
+	var buf [4]byte
+	binary.BigEndian.PutUint32(buf[:], uint32(value))
+	return append(result, buf[:]...)
+}