MASM(x64)でdllを作る

#MASM(x64)でdllを作る

Windows 10 Pro (64bit)
Visual Studio 2022 Community

dlltest.asm

comment *
ml64 /c /Fl dlltest.asm
link /dll /entry:DllMain dlltest
*
.code

DllMain proc
	mov	eax, 1
	ret
DllMain endp

myadd proc export
	mov	rax, rcx
	add	rax, rdx
	ret
myadd endp

mysub proc export
	mov	rax, rcx
	sub	rax, rdx
	ret
mysub endp

end

dev.bat

@echo off
path %path%;C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.30.30705\bin\Hostx64\x64
path %path%;C:\Windows\Microsoft.NET\Framework64\v4.0.30319
cmd

##C#でテスト
x64版のcsc.exeにpathを通す。

dlltest.cs

// csc dlltest.cs

using System;
using System.Runtime.InteropServices;

class Program {
	[DllImport("dlltest.dll")]
	static extern int myadd(int a, int b);
	[DllImport("dlltest.dll")]
	static extern int mysub(int a, int b);

	static void Main() {
		Console.WriteLine("add = {0}", myadd(1, 2));
		Console.WriteLine("sub = {0}", mysub(1, 2));
	}
}

##実行例

#CPUIDサンプル

cpuid.asm

comment *
ml64 /c /Fl cpuid.asm
link /dll /entry:DllMain cpuid
*
.code

DllMain proc
	mov	eax, 1
	ret
DllMain endp

getcpuid proc export
	push	rbx
	mov	r8, rcx
	mov	eax, edx
	cpuid
	mov	[r8   ], eax
	mov	[r8+ 4], ebx
	mov	[r8+ 8], ecx
	mov	[r8+12], edx
	pop	rbx
	ret
getcpuid endp

end

cpuid.cs

// csc cpuid.cs

using System;
using System.Runtime.InteropServices;
using System.Text;

class Program {
	[DllImport("cpuid.dll")]
	static extern void getcpuid(byte[] p, uint eax);

	static void Main() {
		var ascii = new ASCIIEncoding();
		var b = new byte[16];
		for (uint i = 0; i < 3; i++) {
			getcpuid(b, 0x80000002 + i);
			Console.WriteLine("[{0}]", ascii.GetString(b));
		}
	}
}

出力例

C:\Projects\MASM\cpuid>cpuid
[Intel(R) Celeron]
[(R) N4000 CPU @ ]
[1.10GHz         ]

#参考
https://qiita.com/Stosstruppe/items/f0be3a9cededf3e8a62a