.NET Core CLR (coreclr)

.NET Core complete runtime implementation. Also includes IL Assembler, IL Disassembler, RyuJIT, the .NET GC, native interop and many other components.

Some of these components have been modified and also known as 3F's IL Assembler on coreclr (github/3F) specialy for https://github.com/3F/DllExport and for other related purposes.

Licensed under the MIT License (MIT)

Copyright (c) .NET Foundation and Contributors
Copyright (c) 2016-2025  Denis Kuzmin <x-3F@outlook.com> github/3F

ILAsm on coreclr

3F's IL Assembler (ILAsm) + IL Disassembler (ILDasm) https://github.com/3F/coreclr

gntILAsm [?]

/REBASE

Rebase system object in order netstandard > System.Runtime > mscorlib is available starting from 4.700.2+

.typeref custom definitions

Starting from 9.3.0+ you can change the binding of any type for specific assemblies using the following .typeref directive:

grammar:

assemblyDecl : '.hash' 'algorithm' int32 
            | secDecl
            | asmOrRefDecl
            | '.typeref' dottedName 'at' dottedName 
            | '.typeref' dottedName 'any' 'at' dottedName 
            | '.typeref' dottedName 'constraint' 'deny' 
            | '.typeref' dottedName 'constraint' 'any' 'deny' 
            | '.typeref' dottedName 'assert' 
            | '.typeref' dottedName 'any' 'assert' 
            ;

The format for changing the link:

.typeref 'Type' [any] at 'ResolutionScope'

Assertion of type declaration by current module (first at Module tables):

.typeref 'Type' [any] assert
//alias: .typeref 'Type' [any] at ''

The format for rejecting defined records (predefined by the user and the .assembler declaration):

.typeref 'Type' constraint [any] deny

Note keyword any points to multiple definitions starting from the specified Name

For example, predefined assembler's .typeref directives (when /REB is activated) will mean something like:

// 9.3.0+
.assembly 'ClassLibrary1'
{
    .typeref 'System.' any at 'mscorlib'
    .typeref 'System' at 'mscorlib'
    .typeref 'System.Span`' any assert
    .typeref 'System.ReadOnlySpan`' any assert
    .typeref 'System.Memory`' any assert
    .typeref 'System.ReadOnlyMemory`' any assert
    .typeref 'System.MemoryExtensions' assert
    
    .custom instance void ...
    .custom instance void ...
    .hash algorithm 0x00008004
    .ver 1:0:0:0
}

Multiple definitions are competitive or interchangeable. Priority is given to the last from top to bottom. For example,

.typeref 'System.' any at 'System.Runtime'
.typeref 'System.Math' constraint deny
.typeref 'System.IO.' constraint any deny
.typeref 'System.' any at 'mscorlib'
.typeref 'System.' any assert

are equal to

.typeref 'System.' any assert

etc.

/CVRES

.res / .obj

In order to provide a compatible resource converter to obj COFF-format when assembling, use /CVRES (/CVR) key:

ilasm ... /CVR=cvtres.exe

Automatic search for resource converter

Automatic search is available starting from 9.3.0+ by using hMSBuild and other predefined falbacks to resolve .res / .obj processing automatically.

.line with support for both PDB types (MSF + Portable(BSJB))

Read more about

NuGet Package Preferences

• $(ILAsm_RootPkg) - path to ILAsm package folder.
• $(ILAsm_PathToBin) - path to \bin folder., e.g. $(ILAsm_PathToBin)Win.x64\ilasm.exe
• $(ILAsm_W64Bin) and $(ILAsm_W86Bin) - e.g. $(ILAsm_W64Bin)ildasm.exe

Symbols (PDB) are available through GitHub Releases: https://github.com/3F/coreclr/releases