Re: PIC versus AVR

On 2006-08-04, FreeRTOS.org <nospam@xxxxxxxxxx> wrote:

David Kelly wrote:


compiler. I looked a lot at the output of avr-gcc. It never wrote
assembly that I could improve enough to justify the effort to rewrite in
assembly. Once or twice I changed a C expression for better assembly

Mmm, maybe. I'm currently evaluating avrgcc (with which I have a lot of
experience) against IAR and Rowley (with which I have relatively little
experience on AVR targets). There _are_ differences.

One big difference:

AVRGCC - single stack, does something odd when making function calls.

IAR, Rowley, ImageCraft - separate call and data stacks to prevent the
necessity for the above odd thing.

And yet people claim the AVR was designed to be C-friendly.
I've looked at AVR code generaged by GCC and IAR. The AVR is
not C-friendly. It may not be actively hostile like the 8051
or PIC, but it's not C friendly.

Any processor that falls over when you attempt to do any
pointer manipulation isn't C-friendly.

--
Grant Edwards grante Yow! Yow! Maybe I should
at have asked for my Neutron
visi.com Bomb in PAISLEY--
.

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