Microsoft Visual C/C++ (VS2008) compiler output using -O2 (optimize for speed) switch, x86 target:

Non-inline functions:

_TEXT	SEGMENT
_inc32i	PROC						; COMDAT

; 43   :     pl[0] += 1;

  00000	b8 01 00 00 00	 mov	 eax, 1
  00005	01 05 00 00 00
	00		 add	 DWORD PTR _rgl, eax

; 44   :     pl[1] += 1;

  0000b	01 05 04 00 00
	00		 add	 DWORD PTR _rgl+4, eax

; 45   : }

  00011	c3		 ret	 0
_inc32i	ENDP
; Function compile flags: /Ogtpy
_TEXT	ENDS
;	COMDAT _inc64i
_TEXT	SEGMENT
_inc64i	PROC						; COMDAT

; 31   :     pq[0] += 1;

  00000	b9 01 00 00 00	 mov	 ecx, 1
  00005	01 0d 00 00 00
	00		 add	 DWORD PTR _rgq, ecx
  0000b	b8 00 00 00 00	 mov	 eax, 0
  00010	11 05 04 00 00
	00		 adc	 DWORD PTR _rgq+4, eax

; 32   :     pq[1] += 1;

  00016	01 0d 08 00 00
	00		 add	 DWORD PTR _rgq+8, ecx
  0001c	11 05 0c 00 00
	00		 adc	 DWORD PTR _rgq+12, eax

; 33   : }

  00022	c3		 ret	 0
_inc64i	ENDP


Inlined loop:

; 63   :     {
; 64   :         inc32i(&rgl[0]);

  00010	01 05 00 00 00
	00		 add	 DWORD PTR _rgl, eax
  00016	01 05 04 00 00
	00		 add	 DWORD PTR _rgl+4, eax

; 65   :         inc64i(&rgq[0]);

  0001c	01 05 00 00 00
	00		 add	 DWORD PTR _rgq, eax
  00022	11 15 04 00 00
	00		 adc	 DWORD PTR _rgq+4, edx
  00028	01 05 08 00 00
	00		 add	 DWORD PTR _rgq+8, eax
  0002e	11 15 0c 00 00
	00		 adc	 DWORD PTR _rgq+12, edx