Hello P Ravi,

I compiled your program using SDCC.EXE (see below hex listing) and ran it threw the JSIM.EXE simulator and found P1 equals 0x06. The same results attained by Mr. Raja Sekhar using Keil.
I added the following line of code to your program at the end so that it will reach a stop point.

for(;;){}      // hang here forever

Regards,

Charles Bannister

#include<8052.h> 
void main(void){ 
	unsigned int i = 0xffff; 
	unsigned char j = 0xff; 
	TH0 = 0xff; 
	TL0 = 0xff; 
	i = TH0; 
	// i = j; 
	i = i << 8; 
	P1 = i/10000;    // P1 should display 6 (IT DOES!-Charlie)
	for(;;){}        // hang here forever
}  

==================================================

;  ravi.asm
	org	0
X0000:	ljmp	X0082		; 0000   02 00 82   
	reti			; 0003   32         
	org	0bh
	reti			; 000b   32         
	org	13h
	reti			; 0013   32         
	org	1bh
	reti			; 001b   32         
	org	23h
	reti			; 0023   32         
	org	2bh
	reti			; 002b   32         
X002c:	lcall	X0031		; 002c   12 00 31   
X002f:	sjmp	X002f		; 002f   80 fe      
X0031:	mov	th0,#0ffh	; 0031   75 8c ff   
	mov	tl0,#0ffh	; 0034   75 8a ff   
	mov	r2,th0		; 0037   aa 8c      
	mov	r3,#0		; 0039   7b 00      
	mov	rb0r3,r2	; 003b   8a 03      
	mov	r2,#0		; 003d   7a 00      
	mov	rb1r0,#10h	; 003f   75 08 10   
	mov	rb1r1,#27h	; 0042   75 09 27   
	mov	dpl,r2		; 0045   8a 82      
	mov	dph,r3		; 0047   8b 83      
	lcall	X0055		; 0049   12 00 55   
	mov	r2,dpl		; 004c   aa 82      
	mov	r3,dph		; 004e   ab 83      
	mov	p1,r2		; 0050   8a 90 	;=======> R2 = 0x06     
X0052:	sjmp	X0052		; 0052   80 fe  ;(Using JSIM.EXE)    
	ret			; 0054   22         
X0055:	mov	r2,#10h		; 0055   7a 10      
	clr	a		; 0057   e4         
	mov	r3,a		; 0058   fb         
	mov	r4,a		; 0059   fc         
X005a:	mov	a,dpl		; 005a   e5 82      
	add	a,acc		; 005c   25 e0      
	mov	dpl,a		; 005e   f5 82      
	mov	a,dph		; 0060   e5 83      
	rlc	a		; 0062   33         
	mov	dph,a		; 0063   f5 83      
	mov	a,r3		; 0065   eb         
	rlc	a		; 0066   33         
	mov	r3,a		; 0067   fb         
	mov	a,r4		; 0068   ec         
	rlc	a		; 0069   33         
	mov	r4,a		; 006a   fc         
	mov	a,r3		; 006b   eb         
	subb	a,rb1r0		; 006c   95 08      
	mov	b,a		; 006e   f5 f0      
	mov	a,r4		; 0070   ec         
	subb	a,rb1r1		; 0071   95 09      
	jc	X007b		; 0073   40 06      
	mov	r4,a		; 0075   fc         
	mov	r3,b		; 0076   ab f0      
	orl	dpl,#1		; 0078   43 82 01   
X007b:	djnz	r2,X005a	; 007b   da dd      
	ret			; 007d   22         
X007e:	mov	dpl,#0		; 007e   75 82 00   
	ret			; 0081   22         
X0082:	mov	sp,#9		; 0082   75 81 09   
	lcall	X007e		; 0085   12 00 7e   
	mov	a,dpl		; 0088   e5 82      
	jz	X008f		; 008a   60 03      
	ljmp	X002c		; 008c   02 00 2c   
X008f:	mov	r1,#0		; 008f   79 00      
	mov	a,r1		; 0091   e9         
	orl	a,#0		; 0092   44 00      
	jz	X00b1		; 0094   60 1b      
	mov	r2,#0		; 0096   7a 00      
	mov	dptr,#X00ca	; 0098   90 00 ca   
	mov	r0,#0		; 009b   78 00      
	mov	p2,#0		; 009d   75 a0 00   
X00a0:	clr	a		; 00a0   e4         
	movc	a,@a+dptr	; 00a1   93         
	movx	@r0,a		; 00a2   f2         
	inc	dptr		; 00a3   a3         
	inc	r0		; 00a4   08         
	cjne	r0,#0,X00aa	; 00a5   b8 00 02   
	inc	p2		; 00a8   05 a0      
X00aa:	djnz	r1,X00a0	; 00aa   d9 f4      
	djnz	r2,X00a0	; 00ac   da f2      
	mov	p2,#0ffh	; 00ae   75 a0 ff   
X00b1:	mov	r0,#0		; 00b1   78 00      
	mov	a,r0		; 00b3   e8         
	orl	a,#0		; 00b4   44 00      
	jz	X00c4		; 00b6   60 0c      
	mov	r1,#0		; 00b8   79 00      
	mov	dptr,#X0000	; 00ba   90 00 00   
	clr	a		; 00bd   e4         
X00be:	movx	@dptr,a		; 00be   f0         
	inc	dptr		; 00bf   a3         
	djnz	r0,X00be	; 00c0   d8 fc      
	djnz	r1,X00be	; 00c2   d9 fa      
X00c4:	mov	@r0,a		; 00c4   f6         
	djnz	r0,X00c4	; 00c5   d8 fd      
	ljmp	X002c		; 00c7   02 00 2c   
X00ca	equ	0cah
	end

==================================================
:040000000200823246
:01000B0032C2
:0100130032BA
:01001B0032B2
:0100230032AA
:01002B0032A2
:1000820075810912007EE582600302002C7900E985
:100092004400601B7A009000CA780075A000E493C7
:1000A200F2A308B8000205A0D9F4DAF275A0FF782D
:1000B20000E84400600C7900900000E4F0A3D8FC52
:0800C200D9FAF6D8FD02002C6A
:10002C0012003180FE758CFF758AFFAA8C7B008ACA
:10003C00037A007508107509278A828B8312005584
:10004C00AA82AB838A9080FE227A10E4FBFCE582C4
:10005C0025E0F582E58333F583EB33FBEC33FCEBE6
:10006C009508F5F0EC95094006FCABF0438201DAFB
:06007C00DD227582002266