RE: AVR Benchmark Test Suite [was: RE: [avr-gcc-list]GCC-AVRRegisteroptimisations]

[John Regehr]

> Is this program designed for general purpose AVR applications? Or just
> for TinyOS?

The answer is unfortunately a bit subtle...

The question is, how clever of an analysis do you want?  This tool (and 
mine) attempt to be clever by inferring that at some program points, 
interrupts are disabled, which eliminates that possibility of that 
interrupt consuming extra stack RAM right there.

Bill's tool exploits the fact that nesC guarantees that interrupts are 
disabled using specific function calls and also that these are lexically 
nested.  An example of code that is does not have lexically nested 
critical sections is one where you call a function with interrupts enabled 
and it returns with interrupts disabled.  You can do this if you want but 
few developers would do it on purpose.

Anyway the upshot is that if you make the analysis a bit less clever (and 
therefore a bit less precise) Bill's tool should work fine on generic AVR 
codes.  I'll ping him and see if he'll add an option that does this.

Stack depth analysis should definitely be a part of an AVR test suite.  It 
should also be in most developers' compilation toolchain but that's a 
different argument.

John