[sdcc-devel] [ sdcc-Bugs-609947 ] Bug inverting constants

[<no...@so...>]

Bugs item #609947, was opened at 2002-09-16 07:35
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=100599&aid=609947&group_id=599

Category: msc51(8051) target
Group: None
Status: Open
Resolution: None
Priority: 5
Submitted By: Nobody/Anonymous (nobody)
Assigned to: Nobody/Anonymous (nobody)
Summary: Bug inverting constants

Initial Comment:
The following code snippet produces the assembly code 
below it. It appears to NOT invert the constant value in the 
ELSE statement.

idata unsigned char KArray[MAX_RELAY_BLK];
const unsigned char BIT_POS[8] = {0x01, 0x02, 0x04, 
0x08, 0x10, 0x20, 0x40, 0x80};

void proc_relay_outputs( char Status)
{
      if (Status > 0)    {KArray[0] |= BIT_POS[1]; 	}
            else {  KArray[0] &= !BIT_POS[1];  	}
}



_proc_relay_outputs:
	ar2 = 0x02
	ar3 = 0x03
	ar4 = 0x04
	ar5 = 0x05
	ar6 = 0x06
	ar7 = 0x07
	ar0 = 0x00
	ar1 = 0x01
	push	ar2
	push	ar3
	push	ar0
	push	ar1
;C:\Projects\American_Technologies\F2_Source_Relay\F2_
Outputs.c 0
	mov	r2,dpl
;C:\Projects\American_Technologies\F2_Source_Relay\F2_
Outputs.c 44
	clr	c
; Peephole 159   avoided xrl during execution
	mov  a,#(0x00 ^ 0x80)
	mov	b,r2
	xrl	b,#0x80
	subb	a,b
; Peephole 108   removed ljmp by inverse jump logic
	jnc  00102$
00107$:
;
	C:\Projects\American_Technologies\F2_Source_
Relay\F2_Outputs.c 46
	mov	r0,#_KArray
	mov	ar2,@r0
	mov	dptr,#(_BIT_POS + 0x0001)
	clr	a
	movc	a,@a+dptr
; Peephole 105   removed redundant mov
	mov  r3,a
	orl	a,r2
	mov	r0,#_KArray
	mov	@r0,acc
; Peephole 132   changed ljmp to sjmp
	sjmp 00104$
00102$:
;
	C:\Projects\American_Technologies\F2_Source_
Relay\F2_Outputs.c 49
	mov	r0,#_KArray
	mov	ar2,@r0
	mov	dptr,#(_BIT_POS + 0x0001)
	clr	a
	movc	a,@a+dptr
; Peephole 105   removed redundant mov
	mov  r3,a
	cjne	a,#0x01,00108$
00108$:
	clr	a
	rlc	a
; Peephole 105   removed redundant mov
	mov  r3,a
	anl	a,r2
	mov	r0,#_KArray
	mov	@r0,acc
00104$:
	pop	ar1
	pop	ar0
	pop	ar3
	pop	ar2
	ret


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

>Comment By: Jesus Calvino-Fraga (jesusc)
Date: 2002-09-16 10:22

Message:
Logged In: YES 
user_id=603650

Shouldn't use the complement '~' instead of the logical not '!' 
on the 'and' part?  Like this:

else {  KArray[0] &= ~BIT_POS[1];  	}

otherwise KArray[0] will always be set to zero.

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

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=100599&aid=609947&group_id=599