D ASM. Program fails

[userABCabc123 via Digitalmars-d-learn]

On Friday, 22 January 2016 at 17:12:25 UTC, userABCabc123 wrote:
>
> Note that there is maybe a DMD codegen bug because the asm 
> generated for the non naked version copy the result to the 
> stack and then the stack to result but after pmovmskb it's 
> already setup in EAX.
>
> 000000000044C580h  push rbp
> 000000000044C581h  mov rbp, rsp
> 000000000044C584h  sub rsp, 20h
> 000000000044C588h  movdqa dqword ptr [rbp-10h], xmm0
> 000000000044C58Dh  mov dword ptr [rbp-18h], 00000000h
> 000000000044C594h  movdqa xmm0, dqword ptr [rbp-10h]
> 000000000044C599h  pmovmskb eax, xmm0 ; already in result
> 000000000044C59Dh  mov dword ptr [rbp-18h], eax ; what?
> 000000000044C5A0h  mov eax, dword ptr [rbp-18h] ; what?
> 000000000044C5A3h  mov rsp, rbp
> 000000000044C5A6h  pop rbp
> 000000000044C5A7h  ret

Oops, there no DMD codegen bug, the non naked version explicitly 
uses a local value for the return so without the local "r" this 
gives:

int pmovmskb(byte16 v)
{
     asm
     {
         naked;
         push RBP;
         mov RBP, RSP;
         sub RSP, 0x10;
         movdqa dword ptr[RBP-0x10], XMM0;
         movdqa XMM0, dword ptr[RBP-0x10];
         pmovmskb EAX, XMM0;
         mov RSP, RBP;
         pop RBP;
         ret;
     }
}