[U-Boot-Users] [PATCH] Fixed cfi flash read uchar bug.

Wolfgang Denk wd at denx.de
Fri Dec 22 22:33:58 CET 2006


Hello,

in message <1166809358.26147.32.camel at kaboom.lisle.iphase.com> you wrote:
>
> > Did you compare the generated code?
> 
> Nope, but that's a good idea.  I'll compile and objdump the various
> scenarios next year.

I just did this - this is always pretty  instructive  in  such  situ-
ations.  GCC-4.x  optimizes much better, but will also unremorsefully
punish even small sins like a forgotten "volatile".

   text    data     bss     dec     hex filename
 202340   12104   32056  246500   3c2e4 /tmp/ELDK-3.1.1/u-boot
 185751   12016   32048  229815   381b7 /tmp/ELDK-4.0/u-boot
 ------

That's nearly 10% difference in code size...

But here the difference is not in this function  -  both  compile  to
exactly  the  same  code.  Obviously  some other functions in the CFI
driver are different, though.

> Merry Christmas from a very bad quoting net citizen.  :P

Thanks, and Merry Christmas, too.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
It is easier to change the specification to fit the program than vice
versa.




More information about the U-Boot mailing list