Does the llvm-xray supports RISCV?
No, I think. If you look at lit configuration of xray test, It says about supported architecture.
According to llvm-project/clang/test/Driver/XRay/lit.local.cfg supported targets are 'amd64', 'x86_64', 'x86_64h', 'arm', 'aarch64', 'arm64', 'powerpc64le', 'mips', 'mipsel', 'mips64', 'mips64el'
and OSes are 'Linux', 'FreeBSD', 'Darwin'
.