cannot load kernel: symbol lookup error: rint #61

New Issue

sb10q · 2021-10-10T17:45:52+08:00

sb10q commented

2021-10-10 17:45:52 +08:00

Current demo does not start (tested on RISC-V KC705):

artiq.coredevice.comm_kernel.LoadError: cannot load kernel: symbol lookup error: rint

Current demo does not start (tested on RISC-V KC705): ``` artiq.coredevice.comm_kernel.LoadError: cannot load kernel: symbol lookup error: rint ```

pca006132 commented

2021-10-10 18:32:21 +08:00

It requires some libm symbols.

sb10q commented

2021-10-10 20:39:24 +08:00

OK, but why is it using rint()? We are only implementing round() into an integer, whereas rint() is double -> double. Isn't that inefficient? What is the legacy compiler doing?

OK, but why is it using ``rint()``? We are only implementing ``round()`` into an integer, whereas ``rint()`` is ``double -> double``. Isn't that inefficient? What is the legacy compiler doing?

sb10q commented

2021-10-10 20:58:21 +08:00

Legacy compiler uses llvm.round.f64 (also double->double), NAC3 is using llvm.rint.f64.

Legacy compiler uses ``llvm.round.f64`` (also ``double->double``), NAC3 is using ``llvm.rint.f64``.

sb10q referenced this issue from a commit

2021-10-11 08:19:05 +08:00

nac3core: use round instead of rint. Closes #61

sb10q closed this issue

2021-10-11 08:19:05 +08:00

sb10q commented

2021-10-11 08:19:30 +08:00

rint is not available in the rust libm crate used on Zynq.