Program:

 class Program
 {
     string myString;

     private Program()
     {
         myString = "foo";
     }

     static void Main(string[] args)
     {
         Program p = new Program();
     }

 }



Disassembler:
(x86)
00340050 56              push    esi
00340051 b93c372900      mov     ecx,29373Ch (MT: TestAsm.Program)
00340056 e8a520e4ff      call    00182100 (JitHelp: CORINFO_HELP_NEWSFAST)
0034005b 8bf0            mov     esi,eax
0034005d 8b0530214503    mov     eax,dword ptr ds:[3452130h] ("foo")
00340063 8d5604          lea     edx,[esi+4]
00340066 e855221458      call    clr+0x22c0 (584822c0) (JitHelp: CORINFO_HELP_ASSIGN_REF_EAX)

d:\Development\Projects\TestAsm\Program.cs @ 21:
0034006b 5e              pop     esi
0034006c c3              ret

(x64)
000007fe`85e60090 4883ec28        sub     rsp,28h
000007fe`85e60094 488d0ddd37eeff  lea     rcx,[000007fe`85d43878]
000007fe`85e6009b e8a024685f      call    clr+0x2540 (000007fe`e54e2540) (JitHelp: CORINFO_HELP_NEWSFAST)
000007fe`85e600a0 48ba5832711200000000 mov rdx,12713258h
000007fe`85e600aa 488b12          mov     rdx,qword ptr [rdx]
000007fe`85e600ad 488d4808        lea     rcx,[rax+8]
000007fe`85e600b1 e8fa11685f      call    clr+0x12b0 (000007fe`e54e12b0) (JitHelp: CORINFO_HELP_ASSIGN_REF)
000007fe`85e600b6 90              nop
000007fe`85e600b7 4883c428        add     rsp,28h
000007fe`85e600bb c3              ret