(1) I agree that rtems-test lives in the directory you cite. That directory needs to be in your PATH or you need to invoke it with a fully qualified filename. If that’s not clear from the documentation file an issue and patch appreciated.
(2) The erc32 and leon* BSPs are interesting in that they can run on multiple simulators. Depending on the BSP, it may run on sis, qemu, and tsim in addition to real hardware. The “-sis” suffix tells rtems-test to use the erc32 configuration erc32-sis which runs on sis. sis is the SPARC Instruction Simulator which now supports both SPARC and RISC-V.
(3) Yes. That’s the default output directory when you build RTEMS for sparc/erc32. In your case, it would be something like build/aarch64/WHATEVER_BSP_YOU_CONFIGURED_FOR. The temporary directory being there likely indicates something went wrong. Do a *find . -name "exe" from the top of the RTEMS tree. If you built for sparc/erc32 and then built for aarch64/SOME_BSP, then it is possible the build got confused. Doing waf distclean between the builds of different BSPs should avoid that.
This brings up a naming conflict with rtems-test versus waf and other usages of --rtems-bsp or --rtems-bsps. Really, rtems-test takes a test configuration as the argument to the --rtems-bsp option and not a RTEMS BSP identifier. These two things aren’t even necessarily related naming-wise.