...3, 8(%esp)
    calll   __adEq2
    testl   %eax, %eax
    setne   %al
    addl    $20, %esp
    ret $8

--

...initZ, 16(%esp)
    calll   __adEq2
    testl   %eax, %eax
    setne   %al
    addl    $20, %esp
    ret $8

--

...96>:    add    rsp,0x10
   0x000000000041a1c4 <+100>:    xor    eax,eax
   0x000000000041a1c6 <+102>:    leave
   0x000000000041a1c7 <+103>:    ret

--

...mov  RAX, RDI           ;
        lock                    ;
        xadd [RSI], RAX         ;
        ret                     ;
    }
}

unittest {
  ulong a = 10;
  ulong b = exchangeAndAdd...

...lbl_addr
  %tmp2 = load i8** %lbl_addr
  ret i8* %tmp2
}
=======================================

However... the label is only...

...line in druntime's thread.d is invalid:

asm { naked; mov EAX, FS:4; ret; }

--

...preds = %0
  %tmp1 = load i8** %lbl_addr
  %tmp2 = load i8** %lbl_addr
  ret i8* %tmp2
}
==================================================

...stackPtr % 16 != 8) asm { int 3; };
        asm { ret; }
    }
}

void main()
{
    S s; // correct alignment of...

...still very cheap (usually just a call+ret sequence), correct and enough for many not...

...i==9;
   }
   // => "cmpl $9, %edi; sete %al; ret"

   bool assume_instead_of_assert(int i...