improve performance of RectHelper.Extend

[AvenSun]

BenchmarkDotNet v0.13.10, Windows 10 (10.0.19044.3693/21H2/November2021Update)
.NET SDK 8.0.100
  [Host]     : .NET 7.0.14 (7.0.1423.51910), X64 RyuJIT AVX2
  Job-LZKMVF : .NET 7.0.14 (7.0.1423.51910), X64 RyuJIT AVX2
  Job-NCDEPJ : .NET 8.0.0 (8.0.23.53103), X64 RyuJIT AVX2

IterationCount=10  LaunchCount=1  WarmupCount=1  

Method	Runtime	Mean	Error	StdDev	Ratio	Allocated	Alloc Ratio
ExtendBySdcb	.NET 7.0	772.9 ns	7.73 ns	5.12 ns	1.00	-	NA
ExtendByAven	.NET 7.0	458.9 ns	5.23 ns	2.73 ns	0.59	-	NA
ExtendBySdcb	.NET 8.0	227.0 ns	3.26 ns	2.16 ns	1.00	-	NA
ExtendByAven	.NET 8.0	176.6 ns	0.92 ns	0.55 ns	0.77	-	NA

the code of benchmark.

using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Jobs;
using BenchmarkDotNet.Running;
using OpenCvSharp;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Sdcb.OpenVINO.Benchmarks
{
    [SimpleJob(runtimeMoniker: RuntimeMoniker.Net70, launchCount: 1, warmupCount: 1, iterationCount: 10)]
    [SimpleJob(runtimeMoniker: RuntimeMoniker.Net80, launchCount: 1, warmupCount: 1, iterationCount: 10)]
    [MemoryDiagnoser]
    [HtmlExporter]
    [MarkdownExporterAttribute.GitHub]
    public class RectExtend
    {
        private Random random;
        private List<Rect> rects;

        [GlobalSetup]
        public void GlobalSetup()
        {
            this.random = new();
            int rectNum = 100;
            this.rects = new(rectNum);
            for (int i = 0; i < rectNum; i++)
            {
                this.rects.Add(new Rect(
                    this.random.Next(0, 640), this.random.Next(0, 640),
                    this.random.Next(0, 640), this.random.Next(0, 640))
                    );
            }
        }

        [Benchmark(Description = "ExtendBySdcb", Baseline = true)]
        public void ExtendBySdcb()
        {
            for (int i = 0; i < this.rects.Count; i += 2)
            {
                ExtendSdcb(this.rects[i], this.random.Next(0, 88));
            }
        }

        [Benchmark(Description = "ExtendByAven")]
        public void ExtendByAven()
        {
            for (int i = 0; i < this.rects.Count; i += 2)
            {
                ExtendAven(this.rects[i], this.random.Next(0, 88));
            }
        }

        static Rect ExtendSdcb(in Rect rect, int extendLength)
        {
            return Rect.FromLTRB(rect.Left - extendLength, rect.Top - extendLength, rect.Right + extendLength, rect.Bottom + extendLength);
        }

        static Rect ExtendAven(in Rect rect, int extendLength)
        {
            rect.Inflate(extendLength, extendLength);
            return rect;
        }
    }
}

[sdcb]

The problem of this is imcoming Rect should be const, this would impact the imcoming Rect, I think?

[AvenSun]

sorry for that, the keyword in is ignored.
fixed now. new benchmark result as fellows.

BenchmarkDotNet v0.13.10, Windows 10 (10.0.19044.3693/21H2/November2021Update)
.NET SDK 8.0.100
  [Host]     : .NET 7.0.14 (7.0.1423.51910), X64 RyuJIT AVX2
  Job-PXWREW : .NET 7.0.14 (7.0.1423.51910), X64 RyuJIT AVX2
  Job-LCQJJH : .NET 8.0.0 (8.0.23.53103), X64 RyuJIT AVX2

IterationCount=10  LaunchCount=1  WarmupCount=1  

Method	Runtime	Mean	Error	StdDev	Ratio	Allocated	Alloc Ratio
ExtendBySdcb	.NET 7.0	1,477.7 ns	10.54 ns	6.27 ns	1.00	-	NA
ExtendByAven	.NET 7.0	1,031.4 ns	6.97 ns	4.61 ns	0.70	-	NA
ExtendBySdcb	.NET 8.0	441.5 ns	1.91 ns	1.26 ns	1.00	-	NA
ExtendByAven	.NET 8.0	325.4 ns	0.99 ns	0.52 ns	0.74	-	NA

[sdcb]

I have a better suggestion, can you try delete the in keyword and test again, I think we can not using the in keyword in this case, it will copy automatically.

[sdcb]

@AvenSun can you run the perf test again without the in keyword? thanks

[AvenSun]

hi @sdcb
sorry for the delay.
benchmark without in keyword as follows

BenchmarkDotNet v0.13.10, Windows 10 (10.0.19044.3693/21H2/November2021Update)
.NET SDK 8.0.100
  [Host]     : .NET 7.0.14 (7.0.1423.51910), X64 RyuJIT AVX2
  Job-ERUGJG : .NET 7.0.14 (7.0.1423.51910), X64 RyuJIT AVX2
  Job-HGGJRE : .NET 8.0.0 (8.0.23.53103), X64 RyuJIT AVX2

IterationCount=10  LaunchCount=1  WarmupCount=1  

Method	Runtime	Mean	Error	StdDev	Ratio	RatioSD	Allocated	Alloc Ratio
ExtendBySdcb	.NET 7.0	1,939.1 ns	480.54 ns	317.85 ns	1.00	0.00	-	NA
ExtendByAven	.NET 7.0	995.2 ns	39.29 ns	25.99 ns	0.53	0.09	-	NA
ExtendBySdcb	.NET 8.0	440.6 ns	0.77 ns	0.46 ns	1.00	0.00	-	NA
ExtendByAven	.NET 8.0	326.1 ns	1.07 ns	0.64 ns	0.74	0.00	-	NA

[sdcb]

Thanks