CLR抛出InvalidProgramException

Question

我正在尝试创建一个包含多个ByRefLike结构的Context结构。当只有一个字段时，程序就可以工作。当超过1时，程序会抛出一个InvalidProgramException。

为什么它抛出一个错误，它是否有可能克服它？

open System
open System.Runtime.CompilerServices
open FSharp.NativeInterop
#nowarn "9" // Pointers are cool

let inline stackalloc<'a when 'a: unmanaged> (length: int): Span<'a> =
    let p = NativePtr.stackalloc<'a> length |> NativePtr.toVoidPtr
    Span<'a>(p, length)


[<Struct; IsByRefLike>]
type StackStack<'T>(values: Span<'T>) =
    [<DefaultValue>] val mutable private _count : int
    
    member s.Push v =
        if s._count < values.Length then
            values[s._count] <- v
            s._count <- s._count + 1
        else
            failwith "Exceeded capacity of StackStack"
        
    member s.Pop () =
        if s._count > 0 then
            s._count <- s._count - 1
            values[s._count]
        else
            failwith "Empty StackStack"
            
    member s.Count = s._count

    
module StackStack =
    
    let inline create capacity =
        let values = stackalloc<_> capacity
        StackStack values

[<Struct; IsByRefLike>]
type Context =
    {
        mutable Stack1 : StackStack<int>
        // If you comment out the line below, the program will run just fine
        mutable Stack2 : StackStack<int>
        // Other fields go here
    }

module Context =

    let inline create capacity =
        {
            Stack1 = StackStack.create capacity
            // If you comment out the line below, the program will run just fine
            Stack2 = StackStack.create capacity
        }


let test () =

    printfn "State"

    let mutable c = Context.create 10
    c.Stack1.Push 1
    c.Stack1.Push 2
    c.Stack1.Push 3

    while c.Stack1.Count > 0 do
        let next = c.Stack1.Pop()
        printfn $"NextValue: {next}"

test ()

Answer 1

对于好奇的人来说，这就是在F#中实现这一目标的方法。

注意到这是高度非惯用的F#代码，但是我正在处理一个高性能的场景。

open System
open System.Runtime.CompilerServices
open FSharp.NativeInterop
#nowarn "9" // Pointers are cool

let inline stackalloc<'a when 'a: unmanaged> (length: int): Span<'a> =
    let p = NativePtr.stackalloc<'a> length |> NativePtr.toVoidPtr
    Span<'a>(p, length)


[<Struct; IsByRefLike>]
type StackStack<'T>(values: Span<'T>) =
    [<DefaultValue>] val mutable private _count : int
    
    member s.Push v =
        if s._count < values.Length then
            values[s._count] <- v
            s._count <- s._count + 1
        else
            failwith "Exceeded capacity of StackStack"
        
    member s.Pop () =
        if s._count > 0 then
            s._count <- s._count - 1
            values[s._count]
        else
            failwith "Empty StackStack"
            
    member s.Count = s._count

    
module StackStack =
    
    let inline create capacity =
        let values = stackalloc<_> capacity
        StackStack values

[<Struct; IsByRefLike>]
type Context =
        val mutable Stack1 : StackStack<int>
        val mutable Stack2 : StackStack<int>
        new (stack1, stack2) =
            { Stack1 = stack1; Stack2 = stack2 }

module Context =

    let inline create capacity =
        let stack1 = StackStack.create capacity
        let stack2 = StackStack.create capacity
        Context (stack1, stack2)


let test () =

    printfn "State"

    let mutable c = Context.create 10
    c.Stack1.Push 1
    c.Stack1.Push 2
    c.Stack1.Push 3

    while c.Stack1.Count > 0 do
        let next = c.Stack1.Pop()
        printfn $"NextValue: {next}"

test ()