zu2_·há 4 anos·discussOh, I was mistaken. I've verified that at least the rev instruction works (tested on clang -march=rv64imafdcb0p94).
zu2_·há 4 anos·discuss$ cat /proc/cpuinfo processor : 0 hart : 2 isa : rv64imafdc mmu : sv39 uarch : sifive,u74-mc
zu2_·há 4 anos·discussNo. VisionFive2's RISC-V CPU does not have the B extension. I confirmed it on the actual device.$ cat /proc/cpuinfo processor : 0 hart : 2 isa : rv64imafdc mmu : sv39 uarch : sifive,u74-mc