[Embench] Use of assert

Jeremy Bennett jeremy.bennett at embecosm.com
Thu Aug 29 18:34:40 CEST 2019


-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 29/08/19 09:16, Jon Taylor wrote:
> The nettle-aes and nettle-sha256 tests both have assert statements
> in the code.
> 
> Having in the other thread suggested that it’s important to
> include libraries, I think assert is a different case as it isn’t
> really a core part of the benchmark functionality. In the benchmark
> situation, the stimulus will be constant, and the asserts won’t be
> triggered. However if the code is built with real libraries (as
> opposed to dummies), the library code for assert is a significant
> size (~20k for RISC-V, ~12k for Arm vs a test size of ~3k). I
> propose they are removed – their use is primarily debug/error
> handling and I’m not sure that has value within Embench.

Hi Jon,

I agree with you on this. I propose doing the same as we have with a
number of other problematic functions (e.g. rand), and providing an
Embench version in the support library. All that matters is that the
benchmark should fail (i.e. exit with a non-zero return code) if
assert is triggered, so this can be much simpler than the full library
assert.
> Related to the library and size thread, assert also creates a
> challenge in calculating overhead, since assert uses some code in
> common with printf. This means that if printf is used in other
> common code (eg UART output), the size differential between the
> nettle tests and the empty test does not give an accurate size
> calculation. If library size is included in the overall benchmark
> measurement, then we need to try and make the common library code
> as consistent as possible. Multiple dummy/empty tests might be
> another approach, but that adds a maintenance overhead.

Yes - I've run into this before. My proposed fix will deal with this.
Once I have the patch, I'll post it here.
> I’m happy to be challenged on this if I’ve missed a good reason
> for leaving them in place.

Thanks for spotting the issue.

Best wishes,


Jeremy

- -- 
Tel: +44 (1590) 610184
Cell: +44 (7970) 676050
SkypeID: jeremybennett
Twitter: @jeremypbennett
Email: jeremy.bennett at embecosm.com
Web: www.embecosm.com
PGP key: 1024D/BEF58172FB4754E1 2009-03-20
-----BEGIN PGP SIGNATURE-----

iEYEARECAAYFAl1n/p4ACgkQvvWBcvtHVOFJ5ACdFITzhgO88ZzH8M5i8EA7VqAy
QJ0Anig50yUURc544C+DivPIMvec1g4l
=Bfx3
-----END PGP SIGNATURE-----



More information about the Embench mailing list