From 2865b81244cfdb545abcb4491173aed75855a291 Mon Sep 17 00:00:00 2001
From: Iggie Wang <54307176+hey-kong@users.noreply.github.com>
Date: Tue, 8 Oct 2019 16:29:46 +0800
Subject: [PATCH] expression: implement vectorized evaluation for
 `builtinArithmeticMultiplyRealSig` (#12543)

---
 expression/builtin_arithmetic_vec.go      | 29 +++++++++++++++++++++--
 expression/builtin_arithmetic_vec_test.go |  8 ++++---
 2 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/expression/builtin_arithmetic_vec.go b/expression/builtin_arithmetic_vec.go
index 69d7d9a56fa18..87fcaf643979d 100644
--- a/expression/builtin_arithmetic_vec.go
+++ b/expression/builtin_arithmetic_vec.go
@@ -23,11 +23,36 @@ import (
 )
 
 func (b *builtinArithmeticMultiplyRealSig) vectorized() bool {
-	return false
+	return true
 }
 
 func (b *builtinArithmeticMultiplyRealSig) vecEvalReal(input *chunk.Chunk, result *chunk.Column) error {
-	return errors.Errorf("not implemented")
+	if err := b.args[0].VecEvalReal(b.ctx, input, result); err != nil {
+		return err
+	}
+	n := input.NumRows()
+	buf, err := b.bufAllocator.get(types.ETReal, n)
+	if err != nil {
+		return err
+	}
+	defer b.bufAllocator.put(buf)
+	if err := b.args[1].VecEvalReal(b.ctx, input, buf); err != nil {
+		return err
+	}
+
+	result.MergeNulls(buf)
+	x := result.Float64s()
+	y := buf.Float64s()
+	for i := 0; i < n; i++ {
+		if result.IsNull(i) {
+			continue
+		}
+		x[i] = x[i] * y[i]
+		if math.IsInf(x[i], 0) {
+			return types.ErrOverflow.GenWithStackByArgs("DOUBLE", fmt.Sprintf("(%s * %s)", b.args[0].String(), b.args[1].String()))
+		}
+	}
+	return nil
 }
 
 func (b *builtinArithmeticDivideDecimalSig) vectorized() bool {
diff --git a/expression/builtin_arithmetic_vec_test.go b/expression/builtin_arithmetic_vec_test.go
index e7661cc18ecfa..92ebd4330ba88 100644
--- a/expression/builtin_arithmetic_vec_test.go
+++ b/expression/builtin_arithmetic_vec_test.go
@@ -30,9 +30,11 @@ var vecBuiltinArithmeticCases = map[string][]vecExprBenchCase{
 	ast.IntDiv: {},
 	ast.Mod:    {},
 	ast.Or:     {},
-	ast.Mul:    {},
-	ast.Round:  {},
-	ast.And:    {},
+	ast.Mul: {
+		{retEvalType: types.ETReal, childrenTypes: []types.EvalType{types.ETReal, types.ETReal}},
+	},
+	ast.Round: {},
+	ast.And:   {},
 	ast.Plus: {
 		{retEvalType: types.ETReal, childrenTypes: []types.EvalType{types.ETReal, types.ETReal}},
 	},