D93611, D93612, D93613, and D93614 have been reviewed and accepted. I change the version number of vector extension to v1.020201218, i.e., append the date of commit 08a0b464 in riscv-v-spec to v1.0.
Currently, there is no v1.0 tag in riscv-v-spec. That is why I use the date of the commit as the draft version number. We hope v1.0 could be merged into LLVM 12. I am not sure whether it is an acceptable way to do it or not.