Looking at the use of @requires with os.arch values we see:

./hotspot/jtreg/compiler/c2/irTests/RotateLeftNodeIntIdealizationTests.java: * @requires os.arch == "x86_64" | os.arch == "aarch64" | (os.arch == "riscv64" & vm.cpu.features ~= ".*zbb.*")
./hotspot/jtreg/compiler/c2/irTests/RotateLeftNodeLongIdealizationTests.java: * @requires os.arch == "x86_64" | os.arch == "aarch64" | (os.arch == "riscv64" & vm.cpu.features ~= ".*zbb.*")
./hotspot/jtreg/compiler/c2/TestBit.java: * @requires os.arch=="aarch64" | os.arch=="amd64" | os.arch == "ppc64" | os.arch == "ppc64le" | os.arch == "riscv64"

For historical reasons os.arch is "amd64" on x86_64 Linux and Windows, but "x86_64" on macOS. So the first two tests will not run on Linux-x64, and the third will not run on macOS-x64.