[sdcc-devel] [ sdcc-Bugs-1007371 ] sdcc optimizator bug

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Bugs item #1007371, was opened at 2004-08-11 08:31
Message generated for change (Comment added) made by nobody
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=100599&aid=1007371&group_id=599

Category: Live range problems
Group: fixed
Status: Closed
Resolution: Fixed
Priority: 5
Submitted By: Nobody/Anonymous (nobody)
Assigned to: Erik Petrich (epetrich)
Summary: sdcc optimizator bug

Initial Comment:
I has found bug in SDCC:

Source:
#include <8051.h>

//&#1055;&#1088;&#1086;&#1094;&#1077;&#1076;&#1091;&#1088;&#1099; &#1089;&#1074;&#1103;&#1079;&#1080; &#1089; PC
void conout(unsigned char chr)
{
 SBUF=chr;
loop:
 if (TI==0) goto loop;
 TI=0;
}

//&#1042;&#1099;&#1074;&#1086;&#1076; &#1089;&#1090;&#1088;&#1086;&#1082;&#1080; &#1089;&#1080;&#1084;&#1074;&#1086;&#1083;&#1086;&#1074; &#1074; UART
void string_out(code unsigned char * data adr)
{
code unsigned char * data uk;
unsigned char symb;
uk= adr;
loop:
symb=*uk;
uk++;
if (symb!=0)
{
conout(symb);
goto loop;
}
}

void main(void)
{
}


SDCC run command:
sdcc --verbose --model-small --peep-asm -mmcs51 --
iram-size 128 --xram-size 0 --code-size 4096 --
nojtbound test.c

SDCC version:
SDCC : 
mcs51/gbz80/z80/avr/ds390/pic16/pic14/TININative/xa51
/ds400/hc08 2.4.3 #792 (Aug 10 2004) (MINGW32)

Asm list:
                            335 ;------------------------------
------------------------------
                            336 ;Allocation info for local 
variables in function 'string_out'
                            337 ;------------------------------
------------------------------
                            338 ;adr                       Allocated 
to registers r2 r3
                            339 ;uk                        Allocated 
to registers r2 r3
                            340 ;symb                      Allocated 
to registers r4
                            341 ;------------------------------
------------------------------
                            342 ;test.c:13: void string_out
(code unsigned char * data adr)
                            343 ;	---------------------------
--------------
                            344 ;	 function string_out
                            345 ;	---------------------------
--------------
   003A                     346 _string_out:
                            347 ;     genReceive
   003A AA 82               348 	mov	r2,dpl
   003C AB 83               349 	mov	r3,dph
                            350 ;test.c:18: loop:
                            351 ;     genAssign
   003E                     352 00101
$:                                              <= Loop position
                            353 ;test.c:19: symb=*uk;
                            354 ;     genPointerGet
                            355 ;     genCodePointerGet
   003E 8A 82               356 	mov	dpl,r2
   0040 8B 83               357 	mov	dph,r3
   0042 E4                  358 	clr	a
   0043 93                  359 	movc	a,@a+dptr
   0044 FC                  360 	mov
	r4,a                                 <= Assign var to 
R4
   0045 A3                  361 	inc	dptr
   0046 AA 82               362 	mov	r2,dpl
   0048 AB 83               363 	mov	r3,dph
                            364 ;test.c:20: uk++;
                            365 ;test.c:21: if (symb!=0)
                            366 ;     genCmpEq
   004A BC 00 01            367 	cjne
	r4,#0x00,00108$                      <= Check var
                            368 ;	Peephole 112.b	changed 
ljmp to sjmp
                            369 ;	Peephole 251.b	replaced 
sjmp to ret with ret
   004D 22                  370 	ret
   004E                     371 00108$:
                            372 ;test.c:23: conout(symb);
                            373 ;     genCall
   004E 8C 82               374 	mov
	dpl,r4                               <= Final use var
   0050 C0 02               375 	push	ar2
   0052 C0 03               376 	push	ar3
   0054 C0 04               377 	push
	ar4                                  <= Waste Push 
operation
   0056 12s00r31            378 	lcall	_conout
   0059 D0 04               379 	pop
	ar4                                  <= Waste Pop 
Operation
   005B D0 03               380 	pop	ar3
   005D D0 02               381 	pop	ar2
                            382 ;test.c:24: goto loop;
                            383 ;	Peephole 112.b	changed 
ljmp to sjmp
   005F 80 DD               384 	sjmp	00101$
   0061                     385 00104$:
   0061 22                  386 	ret


In the old sdcc versions this error not exists.

With the best wishes, Ruslan. My e-mail: 
Ru...@hi...


----------------------------------------------------------------------

Comment By: Nobody/Anonymous (nobody)
Date: 2004-08-12 04:39

Message:
Logged In: NO 

To Maarten Brock:
Latest version without such bug is
SDCC : 
mcs51/gbz80/z80/avr/ds390/pic16/pic14/TININative/xa51/ds40
0/hc08 2.4.3 #785 (Aug  4 2004) (MINGW32)

With the best wishes, Ruslan. My e-mail: 
Ru...@hi...


----------------------------------------------------------------------

Comment By: Erik Petrich (epetrich)
Date: 2004-08-11 21:50

Message:
Logged In: YES 
user_id=635249

Fixed in SDCClrange.c 1.39.


----------------------------------------------------------------------

Comment By: Maarten Brock (maartenbrock)
Date: 2004-08-11 12:46

Message:
Logged In: YES 
user_id=888171

Could you please be more specific which older version you're 
referring to? Preferrably the latest that doesn't produce this 
little less efficient optimization?

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=100599&aid=1007371&group_id=599