Hi
I'm trying to optimise a critical section of my code
and to get rid of the BANKSEL instructions I would
like to place variables on the same bank.
I tried:
#pragma udata bank2 COUNTER NCO SPEED OLDV
char COUNTER;
short NCO;
short SPEED;
short OLDV;
...
NCO += SPEED;
...
But this compiles to:
06931 ; .line 91; stepperirq.c NCO +=
SPEED;
00003E 51?? 06932 MOVF _SPEED, W, B
000040 ???? 06933 BANKSEL _NCO
000042 27?? 06934 ADDWF _NCO, F, B
000044 ???? 06935 BANKSEL (_SPEED + 1)
000046 51?? 06936 MOVF (_SPEED + 1), W, B
000048 ???? 06937 BANKSEL (_NCO + 1)
00004A 23?? 06938 ADDWFC (_NCO + 1), F, B
so there are three BANKSEL instructions, all of which are basically
unnecessary as the correct bank was already chose in the previous
code (not shown).
I do see a bunch of
06686 ; removed redundant BANKSEL
so obviously sometimes the compiler knows to remove redundant BANKSELs,
but what do I need to do 'help' it to do in this case?
br Kusti
This e-mail may contain confidential or privileged information. If you are not
the intended recipient (or have received this e-mail in error) please notify
the sender immediately and destroy this e-mail. Any unauthorized copying,
disclosure or distribution of the material in this e-mail is strictly
forbidden. We will not be liable for direct, indirect, special or consequential
damages arising from alteration of the contents of this message by a third
party or as a result of any virus being passed on or as of transmission of this
e-mail in general.
------------------------------------------------------------------------------
HPCC Systems Open Source Big Data Platform from LexisNexis Risk Solutions
Find What Matters Most in Your Big Data with HPCC Systems
Open Source. Fast. Scalable. Simple. Ideal for Dirty Data.
Leverages Graph Analysis for Fast Processing & Easy Data Exploration
http://p.sf.net/sfu/hpccsystems
_______________________________________________
Sdcc-user mailing list
Sdcc-user@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/sdcc-user
