1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
|
// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you 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.
//go:build go1.18
package kernels
import (
"github.com/apache/arrow-go/v18/arrow"
"github.com/apache/arrow-go/v18/arrow/array"
"github.com/apache/arrow-go/v18/arrow/compute/exec"
)
type CastOptions struct {
ToType arrow.DataType `compute:"to_type"`
AllowIntOverflow bool `compute:"allow_int_overflow"`
AllowTimeTruncate bool `compute:"allow_time_truncate"`
AllowTimeOverflow bool `compute:"allow_time_overflow"`
AllowDecimalTruncate bool `compute:"allow_decimal_truncate"`
AllowFloatTruncate bool `compute:"allow_float_truncate"`
AllowInvalidUtf8 bool `compute:"allow_invalid_utf8"`
}
func (CastOptions) TypeName() string { return "CastOptions" }
// CastState is the kernel state for Cast functions, it is an alias to
// the CastOptions object.
type CastState = CastOptions
// ZeroCopyCastExec is a kernel for performing a cast which can be executed
// as a zero-copy operation. It simply forwards the buffers to the output.
//
// This can be used for casting a type to itself, or for casts between
// equivalent representations such as Int32 and Date32.
func ZeroCopyCastExec(_ *exec.KernelCtx, batch *exec.ExecSpan, out *exec.ExecResult) error {
out.Release()
dt := out.Type
*out = batch.Values[0].Array
out.Type = dt
return nil
}
func recursiveSetSelfAlloc(arr *exec.ArraySpan) {
for i := range arr.Buffers {
if len(arr.Buffers[i].Buf) > 0 {
arr.Buffers[i].SelfAlloc = true
if arr.Buffers[i].Owner != nil {
arr.Buffers[i].Owner.Retain()
}
}
}
for i := range arr.Children {
recursiveSetSelfAlloc(&arr.Children[i])
}
}
// CastFromNull is a simple kernel for constructing an array of null values
// for the requested data type, allowing casting of an arrow.Null typed value
// to any other arbitrary data type.
func CastFromNull(ctx *exec.KernelCtx, batch *exec.ExecSpan, out *exec.ExecResult) error {
arr := array.MakeArrayOfNull(exec.GetAllocator(ctx.Ctx), out.Type, int(batch.Len))
defer arr.Release()
out.SetMembers(arr.Data())
recursiveSetSelfAlloc(out)
return nil
}
// OutputAllNull is a simple kernel that initializes the output as an array
// whose output is all null by setting nulls to the length.
func OutputAllNull(_ *exec.KernelCtx, batch *exec.ExecSpan, out *exec.ExecResult) error {
out.Nulls = batch.Len
return nil
}
func CanCastFromDict(id arrow.Type) bool {
return arrow.IsPrimitive(id) || arrow.IsBaseBinary(id) || arrow.IsFixedSizeBinary(id)
}
// GetZeroCastKernel returns a kernel for performing ZeroCast execution using
// the ZeroCopyCastExec kernel function.
func GetZeroCastKernel(inID arrow.Type, inType exec.InputType, out exec.OutputType) exec.ScalarKernel {
k := exec.NewScalarKernel([]exec.InputType{inType}, out, ZeroCopyCastExec, nil)
k.NullHandling = exec.NullComputedNoPrealloc
k.MemAlloc = exec.MemNoPrealloc
return k
}
// GetCommonCastKernels returns the list of kernels common to all types
// such as casting from null or from Extension types of the appropriate
// underlying type.
func GetCommonCastKernels(outID arrow.Type, outType exec.OutputType) (out []exec.ScalarKernel) {
out = make([]exec.ScalarKernel, 0, 2)
kernel := exec.NewScalarKernel([]exec.InputType{exec.NewExactInput(arrow.Null)}, outType,
CastFromNull, nil)
kernel.NullHandling = exec.NullComputedNoPrealloc
kernel.MemAlloc = exec.MemNoPrealloc
out = append(out, kernel)
return
}
|
