Question

有时，当我从应用程序收到崩溃报告时，堆栈跟踪中缺少一个方法。我不认为下面的代码会重现它，但是让我们说，为了参考我们有这个：

using System.IO;
using System;
using System.Collections.Generic;

class Program
{
    static List<int> stuff;
    static void Main()
    {
        stuff = new List<int>();
        int result = Foo();
    }

    static int Foo(){
        return Bar(5);
    }

    static int Bar(int value){
        return stuff[value];
    }
}

当System.Collections.Generic.List'1.get_Item(Int32 index)抛出System.ArgumentOutOfRangeException时，堆栈跟踪缺失Foo()。为了这个论点，编译器没有优化代码，因为解编译器显示它没有内联。有谁知道会导致这种情况（编译器内嵌除外）？

编辑：为了澄清，当进行堆栈跟踪时，应用程序不处于调试模式。

Answer 1

TL; DR：JIT不是编译器内联方法，只能在ASM反汇编中查看，而不能在MSIL反汇编中查看。

让我们在调试模式下编译你的代码，现在让我们反编译MSIL。

结果似乎很好：

namespace ConsoleTests { using System; using System.Collections.Generic; internal class Program { private static List<int> stuff; private static int Bar(int value) { return stuff[value]; } private static int Foo() { return Bar(5); } private static void Main() { stuff = new List<int>(); int num = Foo(); } } }

调用堆栈也已完成：


未处理的异常：System.ArgumentOutOfRangeException：索引超出范围。必须是非负数且小于集合的大小。   参数名称：index

在System.ThrowHelper.ThrowArgumentOutOfRangeException（ExceptionArgument参数，ExceptionResource资源）

在System.Collections.Generic.List`1.get_Item（Int32 index）

在C：\ Users \ Some1Pr0 \ documents \ visual studio 2015 \ Projects \ ConsoleTests \ ConsoleTests \ Program.cs：line 40
中的ConsoleTests.Program.Bar（Int32值）
在C：\ Users \ Some1Pr0 \ documents \ visual studio 2015 \ Projects \ ConsoleTests \ ConsoleTests \ Program.cs：第35行的ConsoleTests.Program.Foo（）中

在C：\ Users \ Some1Pr0 \ documents \ visual studio 2015 \ Projects \ ConsoleTests \ ConsoleTests \ Program.cs：第30行的ConsoleTests.Program.Main（）中

现在让我们在发布版中编译：

现在我们可以看到调用堆栈不完整：


未处理的异常：System.ArgumentOutOfRangeException：索引超出范围。必须是非负数且小于集合的大小。   参数名称：index

在System.ThrowHelper.ThrowArgumentOutOfRangeException（ExceptionArgument参数，ExceptionResource资源）

在C：\ Users \ Some1Pr0 \ documents \ visual studio 2015 \ Projects \ ConsoleTests \ ConsoleTests \ Program.cs：第30行的ConsoleTests.Program.Main（）中

此外，VS2015的调试器无法进入Foo。

让我们检查MSIL：

namespace ConsoleTests { using System; using System.Collections.Generic; internal class Program { private static List<int> stuff; private static int Bar(int value) { return stuff[value]; } private static int Foo() { return Bar(5); } private static void Main() { stuff = new List<int>(); Foo(); } } }

显然代码看起来是一样的，所以让我们更深入一点，检查JITTED assembly代码。

如果我们查看反汇编调试版，我们会看到整个代码都包含完整的JITTED方法：

00007FFDD8AF4722 56 push rsi 00007FFDD8AF4723 48 83 EC 40 sub rsp,40h 00007FFDD8AF4727 48 8B EC mov rbp,rsp 00007FFDD8AF472A 48 8D 7D 24 lea rdi,[rbp+24h] 00007FFDD8AF472E B9 07 00 00 00 mov ecx,7 00007FFDD8AF4733 33 C0 xor eax,eax 00007FFDD8AF4735 F3 AB rep stos dword ptr [rdi] 00007FFDD8AF4737 48 B8 00 4F B3 D8 FD 7F 00 00 mov rax,7FFDD8B34F00h 00007FFDD8AF4741 83 38 00 cmp dword ptr [rax],0 00007FFDD8AF4744 74 05 je 00007FFDD8AF474B 00007FFDD8AF4746 E8 B1 17 AB 5F call 00007FFE385A5EFC 00007FFDD8AF474B 90 nop 29: stuff = new List<int>(); 00007FFDD8AF474C 48 B9 28 F1 1F 37 FE 7F 00 00 mov rcx,7FFE371FF128h 00007FFDD8AF4756 E8 65 01 63 5F call 00007FFE381248C0 00007FFDD8AF475B 48 89 45 28 mov qword ptr [rbp+28h],rax 00007FFDD8AF475F 48 8B 4D 28 mov rcx,qword ptr [rbp+28h] 00007FFDD8AF4763 E8 E8 0E E7 5E call 00007FFE37965650 00007FFDD8AF4768 48 B9 70 85 6C D9 63 00 00 00 mov rcx,63D96C8570h 00007FFDD8AF4772 48 8B 55 28 mov rdx,qword ptr [rbp+28h] 00007FFDD8AF4776 E8 85 CD 62 5F call 00007FFE38121500 30: int result = Foo(); 00007FFDD8AF477B E8 F0 C7 FF FF call 00007FFDD8AF0F70 00007FFDD8AF4780 89 45 24 mov dword ptr [rbp+24h],eax 00007FFDD8AF4783 8B 45 24 mov eax,dword ptr [rbp+24h] 00007FFDD8AF4786 89 45 34 mov dword ptr [rbp+34h],eax 31: } 00007FFDD8AF4789 90 nop 00007FFDD8AF478A 48 8D 65 40 lea rsp,[rbp+40h] 00007FFDD8AF478E 5E pop rsi 00007FFDD8AF478F 5F pop rdi 00007FFDD8AF4790 5D pop rbp 00007FFDD8AF4791 C3 ret 34: { 00007FFDD8AF47B0 55 push rbp 00007FFDD8AF47B1 57 push rdi 00007FFDD8AF47B2 56 push rsi 00007FFDD8AF47B3 48 83 EC 30 sub rsp,30h 00007FFDD8AF47B7 48 8B EC mov rbp,rsp 00007FFDD8AF47BA 48 8D 7D 20 lea rdi,[rbp+20h] 00007FFDD8AF47BE B9 04 00 00 00 mov ecx,4 00007FFDD8AF47C3 33 C0 xor eax,eax 00007FFDD8AF47C5 F3 AB rep stos dword ptr [rdi] 00007FFDD8AF47C7 48 B8 00 4F B3 D8 FD 7F 00 00 mov rax,7FFDD8B34F00h 00007FFDD8AF47D1 83 38 00 cmp dword ptr [rax],0 00007FFDD8AF47D4 74 05 je 00007FFDD8AF47DB 00007FFDD8AF47D6 E8 21 17 AB 5F call 00007FFE385A5EFC 00007FFDD8AF47DB 90 nop 35: return Bar(5); 00007FFDD8AF47DC B9 05 00 00 00 mov ecx,5 00007FFDD8AF47E1 E8 92 C7 FF FF call 00007FFDD8AF0F78 00007FFDD8AF47E6 89 45 20 mov dword ptr [rbp+20h],eax 00007FFDD8AF47E9 8B 45 20 mov eax,dword ptr [rbp+20h] 00007FFDD8AF47EC 89 45 24 mov dword ptr [rbp+24h],eax 00007FFDD8AF47EF 90 nop 00007FFDD8AF47F0 EB 00 jmp 00007FFDD8AF47F2 36: } 00007FFDD8AF47F2 8B 45 24 mov eax,dword ptr [rbp+24h] 00007FFDD8AF47F5 48 8D 65 30 lea rsp,[rbp+30h] 00007FFDD8AF47F9 5E pop rsi 00007FFDD8AF47FA 5F pop rdi 00007FFDD8AF47FB 5D pop rbp 00007FFDD8AF47FC C3 ret 34: { 00007FFDD8AF47B2 56 push rsi 00007FFDD8AF47B3 48 83 EC 30 sub rsp,30h 00007FFDD8AF47B7 48 8B EC mov rbp,rsp 00007FFDD8AF47BA 48 8D 7D 20 lea rdi,[rbp+20h] 00007FFDD8AF47BE B9 04 00 00 00 mov ecx,4 00007FFDD8AF47C3 33 C0 xor eax,eax 00007FFDD8AF47C5 F3 AB rep stos dword ptr [rdi] 00007FFDD8AF47C7 48 B8 00 4F B3 D8 FD 7F 00 00 mov rax,7FFDD8B34F00h 00007FFDD8AF47D1 83 38 00 cmp dword ptr [rax],0 00007FFDD8AF47D4 74 05 je 00007FFDD8AF47DB 00007FFDD8AF47D6 E8 21 17 AB 5F call 00007FFE385A5EFC 00007FFDD8AF47DB 90 nop 35: return Bar(5); 00007FFDD8AF47DC B9 05 00 00 00 mov ecx,5 00007FFDD8AF47E1 E8 92 C7 FF FF call 00007FFDD8AF0F78 00007FFDD8AF47E6 89 45 20 mov dword ptr [rbp+20h],eax 00007FFDD8AF47E9 8B 45 20 mov eax,dword ptr [rbp+20h] 00007FFDD8AF47EC 89 45 24 mov dword ptr [rbp+24h],eax 00007FFDD8AF47EF 90 nop 00007FFDD8AF47F0 EB 00 jmp 00007FFDD8AF47F2 36: } 00007FFDD8AF47F2 8B 45 24 mov eax,dword ptr [rbp+24h] 00007FFDD8AF47F5 48 8D 65 30 lea rsp,[rbp+30h] 00007FFDD8AF47F9 5E pop rsi 00007FFDD8AF47FA 5F pop rdi 00007FFDD8AF47FB 5D pop rbp 00007FFDD8AF47FC C3 ret 39: { 00007FFDD8AF4820 55 push rbp 00007FFDD8AF4821 57 push rdi 00007FFDD8AF4822 56 push rsi 00007FFDD8AF4823 48 83 EC 30 sub rsp,30h 00007FFDD8AF4827 48 8B EC mov rbp,rsp 00007FFDD8AF482A 48 8B F1 mov rsi,rcx 00007FFDD8AF482D 48 8D 7D 20 lea rdi,[rbp+20h] 00007FFDD8AF4831 B9 04 00 00 00 mov ecx,4 00007FFDD8AF4836 33 C0 xor eax,eax 00007FFDD8AF4838 F3 AB rep stos dword ptr [rdi] 00007FFDD8AF483A 48 8B CE mov rcx,rsi 00007FFDD8AF483D 89 4D 50 mov dword ptr [rbp+50h],ecx 00007FFDD8AF4840 48 B8 00 4F B3 D8 FD 7F 00 00 mov rax,7FFDD8B34F00h 00007FFDD8AF484A 83 38 00 cmp dword ptr [rax],0 00007FFDD8AF484D 74 05 je 00007FFDD8AF4854 00007FFDD8AF484F E8 A8 16 AB 5F call 00007FFE385A5EFC 00007FFDD8AF4854 90 nop 40: return stuff[value]; 00007FFDD8AF4855 48 B9 70 85 6C D9 63 00 00 00 mov rcx,63D96C8570h 00007FFDD8AF485F 48 8B 09 mov rcx,qword ptr [rcx] 00007FFDD8AF4862 8B 55 50 mov edx,dword ptr [rbp+50h] 00007FFDD8AF4865 39 09 cmp dword ptr [rcx],ecx 00007FFDD8AF4867 E8 94 0C E7 5E call 00007FFE37965500 00007FFDD8AF486C 89 45 20 mov dword ptr [rbp+20h],eax 00007FFDD8AF486F 8B 45 20 mov eax,dword ptr [rbp+20h] 00007FFDD8AF4872 89 45 24 mov dword ptr [rbp+24h],eax 00007FFDD8AF4875 90 nop 00007FFDD8AF4876 EB 00 jmp 00007FFDD8AF4878 41: } 00007FFDD8AF4878 8B 45 24 mov eax,dword ptr [rbp+24h] 00007FFDD8AF487B 48 8D 65 30 lea rsp,[rbp+30h] 00007FFDD8AF487F 5E pop rsi 00007FFDD8AF4880 5F pop rdi 00007FFDD8AF4881 5D pop rbp 00007FFDD8AF4882 C3 ret

但是，当我们检查发布版本时，我们可以看到 确实是内联的（由JIT - 而不是编译器） < / strong>我们可以在Main方法中看到列表索引器的绑定检查：

29: stuff = new List<int>(); 00007FFDD8AD4102 83 EC 20 sub esp,20h 00007FFDD8AD4105 48 B9 28 F1 1F 37 FE 7F 00 00 mov rcx,7FFE371FF128h 00007FFDD8AD410F E8 AC 07 65 5F call 00007FFE381248C0 00007FFDD8AD4114 48 8B F0 mov rsi,rax 00007FFDD8AD4117 B9 01 00 00 00 mov ecx,1 00007FFDD8AD411C BA 43 00 00 00 mov edx,43h 00007FFDD8AD4121 E8 46 0A 7B 5F call 00007FFE38284B6C 00007FFDD8AD4126 48 BA 60 89 E1 2D 69 00 00 00 mov rdx,692DE18960h 00007FFDD8AD4130 48 8B 12 mov rdx,qword ptr [rdx] 00007FFDD8AD4133 48 8D 4E 08 lea rcx,[rsi+8] 00007FFDD8AD4137 E8 F4 D3 64 5F call 00007FFE38121530 00007FFDD8AD413C 48 B9 60 85 E1 2D 69 00 00 00 mov rcx,692DE18560h 00007FFDD8AD4146 48 8B D6 mov rdx,rsi 00007FFDD8AD4149 E8 B2 D3 64 5F call 00007FFE38121500 30: int result = Foo(); 00007FFDD8AD414E 48 B9 60 85 E1 2D 69 00 00 00 mov rcx,692DE18560h 00007FFDD8AD4158 48 8B 31 mov rsi,qword ptr [rcx] 00007FFDD8AD415B 83 7E 18 05 cmp dword ptr [rsi+18h],5 //------------------------------------------------------------------------- 00007FFDD8AD415F 77 0F ja 00007FFDD8AD4170 //BOUND CHECK!!!!! //------------------------------------------------------------------------- 00007FFDD8AD4161 B9 0D 00 00 00 mov ecx,0Dh 00007FFDD8AD4166 BA 16 00 00 00 mov edx,16h 00007FFDD8AD416B E8 A0 2C D2 5E call 00007FFE377F6E10 //EXCEPTION 00007FFDD8AD4170 48 8B 46 08 mov rax,qword ptr [rsi+8] 00007FFDD8AD4174 83 78 08 05 cmp dword ptr [rax+8],5 00007FFDD8AD4178 76 09 jbe 00007FFDD8AD4183 00007FFDD8AD417A 8B 40 24 mov eax,dword ptr [rax+24h] 00007FFDD8AD417D 48 83 C4 20 add rsp,20h 00007FFDD8AD4181 5E pop rsi 00007FFDD8AD4182 C3 ret 00007FFDD8AD4183 E8 50 45 AD 5F call 00007FFE385A86D8 00007FFDD8AD4188 CC int 3

异常堆栈跟踪缺失项目

1 个答案: