cyb70289 commented on code in PR #13964: URL: https://github.com/apache/arrow/pull/13964#discussion_r954510958
########## go/arrow/compute/exec.go: ########## @@ -0,0 +1,163 @@ +// 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. + +package compute + +import ( + "context" + "fmt" + + "github.com/apache/arrow/go/v10/arrow" + "github.com/apache/arrow/go/v10/arrow/compute/internal/exec" + "github.com/apache/arrow/go/v10/arrow/internal/debug" +) + +func haveChunkedArray(values []Datum) bool { + for _, v := range values { + if v.Kind() == KindChunked { + return true + } + } + return false +} + +// ExecSpanFromBatch constructs and returns a new ExecSpan from the values +// inside of the ExecBatch which could be scalar or arrays. +// +// This is mostly used for tests but is also a convenience method for other +// cases. +func ExecSpanFromBatch(batch *ExecBatch) *exec.ExecSpan { + out := &exec.ExecSpan{Len: batch.Len, Values: make([]exec.ExecValue, len(batch.Values))} + for i, v := range batch.Values { + outVal := &out.Values[i] + if v.Kind() == KindScalar { + outVal.Scalar = v.(*ScalarDatum).Value + } else { + outVal.Array.SetMembers(v.(*ArrayDatum).Value) + outVal.Scalar = nil + } + } + return out +} + +// this is the primary driver of execution +func execInternal(ctx context.Context, fn Function, opts FunctionOptions, passedLen int64, args ...Datum) (result Datum, err error) { + if opts == nil { + if err = checkOptions(fn, opts); err != nil { + return + } + opts = fn.DefaultOptions() + } + + // we only allow Array, ChunkedArray, and Scalars for now. + // RecordBatch and Table datums are disallowed. + if err = checkAllIsValue(args); err != nil { + return + } + + inTypes := make([]arrow.DataType, len(args)) + for i, a := range args { + inTypes[i] = a.(ArrayLikeDatum).Type() + } + + var ( + k exec.Kernel + executor kernelExecutor + ) + + switch fn.Kind() { + case FuncScalar: + executor = scalarExecPool.Get().(*scalarExecutor) + defer func() { + executor.clear() + scalarExecPool.Put(executor.(*scalarExecutor)) + }() + default: + return nil, fmt.Errorf("%w: direct execution of %s", arrow.ErrNotImplemented, fn.Kind()) + } + + if k, err = fn.DispatchBest(inTypes...); err != nil { + return + } + + kctx := &exec.KernelCtx{Ctx: ctx, Kernel: k} + init := k.GetInitFn() + kinitArgs := exec.KernelInitArgs{Kernel: k, Inputs: inTypes, Options: opts} + if init != nil { + kctx.State, err = init(kctx, kinitArgs) + if err != nil { + return + } + } + + if err = executor.Init(kctx, kinitArgs); err != nil { + return + } + + input := ExecBatch{Values: args, Len: 0} + if input.NumValues() == 0 { + if passedLen != -1 { + input.Len = passedLen + } + } else { + inferred, _ := inferBatchLength(input.Values) + input.Len = inferred + switch fn.Kind() { + case FuncScalar: + if passedLen != -1 && passedLen != inferred { + return nil, fmt.Errorf("%w: passed batch length for execution did not match actual length for scalar fn execution", + arrow.ErrInvalid) + } + } + } + + ctx, cancel := context.WithCancel(context.Background()) + defer cancel() + + ch := make(chan Datum, 10) Review Comment: `10` looks without strong support, but I don't have better suggestion. Is channel strictly necessary here? I think channel make the code easier to read than C++ which collects all results with a datum accumulator. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
