Noticed from results in: http://bugzilla.gdcproject.org/show_bug.cgi?id=180

"""
for: dmd -O -inline -release
  tByte: 0.004,872 secs
 tShort: 0.006,896 secs
   tInt: 0.008,672 secs
  tLong: 0.036,864 secs
"""

Reduced test:
long test(long l)
{
  return l / 2;
}


Compiles down to: http://goo.gl/10dWmf
long example.test(long):
	push   %ebp
	mov    %esp,%ebp
	push   %eax
	xor    %ecx,%ecx
	mov    0xc(%ebp),%edx
	push   %ebx
	mov    $0x2,%ebx
	mov    0x8(%ebp),%eax
	push   %ecx
	push   %ebx
	push   %edx
	push   %eax
	call   __divdi3        ; <--- !!!
	add    $0x10,%esp
	pop    %ebx
	mov    %ebp,%esp
	pop    %ebp
	ret    $0x8
	add    %al,(%eax)


In comparison to GDC: http://goo.gl/XaBqdA
	push	%ebx
	mov	12(%esp), %ebx
	xor	%edx, %edx
	mov	8(%esp), %ecx
	mov	%ebx, %eax
	shr	$31, %eax
	add	%ecx, %eax
	adc	%ebx, %edx
	shrd	$1, %edx, %eax
	pop	%ebx
	sar	%edx
	ret


You can exchange '2' for '4', '8', '16'... '128' to observe the difference (optimization changes for 256 and higher).