expression: implement vectorized evaluation for builtinReplaceSig (p…

…ingcap#12496)
lvrongnan · Sep 30, 2019 · b707447 · b707447
1 parent 230e72e
commit b707447
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Showing 2 changed files with 49 additions and 2 deletions.
diff --git a/expression/builtin_string_vec.go b/expression/builtin_string_vec.go
@@ -688,11 +688,55 @@ func (b *builtinCharSig) vecEvalString(input *chunk.Chunk, result *chunk.Column)
 }
 
 func (b *builtinReplaceSig) vectorized() bool {
-	return false
+	return true
 }
 
+// evalString evals a builtinReplaceSig.
+// See https://dev.mysql.com/doc/refman/5.7/en/string-functions.html#function_replace
 func (b *builtinReplaceSig) vecEvalString(input *chunk.Chunk, result *chunk.Column) error {
-	return errors.Errorf("not implemented")
+	n := input.NumRows()
+	buf, err := b.bufAllocator.get(types.ETString, n)
+	if err != nil {
+		return err
+	}
+	defer b.bufAllocator.put(buf)
+	if err := b.args[0].VecEvalString(b.ctx, input, buf); err != nil {
+		return err
+	}
+	buf1, err := b.bufAllocator.get(types.ETString, n)
+	if err != nil {
+		return err
+	}
+	defer b.bufAllocator.put(buf1)
+	if err := b.args[1].VecEvalString(b.ctx, input, buf1); err != nil {
+		return err
+	}
+	buf2, err := b.bufAllocator.get(types.ETString, n)
+	if err != nil {
+		return err
+	}
+	defer b.bufAllocator.put(buf2)
+	if err := b.args[2].VecEvalString(b.ctx, input, buf2); err != nil {
+		return err
+	}
+
+	result.ReserveString(n)
+	for i := 0; i < n; i++ {
+		if buf.IsNull(i) || buf1.IsNull(i) || buf2.IsNull(i) {
+			result.AppendNull()
+			continue
+		}
+		str := buf.GetString(i)
+		oldStr := buf1.GetString(i)
+		newStr := buf2.GetString(i)
+		if oldStr == "" {
+			result.AppendString(str)
+			continue
+		}
+		str = strings.Replace(str, oldStr, newStr, -1)
+		result.AppendString(str)
+	}
+	return nil
 }
 
 func (b *builtinMakeSetSig) vectorized() bool {

diff --git a/expression/builtin_string_vec_test.go b/expression/builtin_string_vec_test.go
@@ -81,6 +81,9 @@ var vecBuiltinStringCases = map[string][]vecExprBenchCase{
 		{retEvalType: types.ETString, childrenTypes: []types.EvalType{types.ETString}, geners: []dataGenerator{&randLenStrGener{10, 20}}},
 		{retEvalType: types.ETString, childrenTypes: []types.EvalType{types.ETString}, geners: []dataGenerator{&defaultGener{0.2, types.ETString}}},
 	},
+	ast.Replace: {
+		{retEvalType: types.ETString, childrenTypes: []types.EvalType{types.ETString, types.ETString, types.ETString}, geners: []dataGenerator{&randLenStrGener{10, 20}, &randLenStrGener{0, 10}, &randLenStrGener{0, 10}}},
+	},
 }
 
 func (s *testEvaluatorSuite) TestVectorizedBuiltinStringEvalOneVec(c *C) {