Feature/formally parse riscv isa #2946

Job	Run time
build-macos (macos-13)	47s
build-macos (macos-13, gcc@11)	1m 14s
build-macos (macos-14)	22s
build-mingw (windows-2022, mingw64)	1m 43s
build-macos (macos-13, gcc@12)	1m 20s
build-macos (macos-latest)	21s
build-linux (jammy, 96b_carbon)	42s
build-macos (macos-13, gcc@13)	1m 16s
build-mingw (windows-2022, ucrt64)	1m 55s
build-macos (macos-13, gcc@14)	1m 8s
build-linux (jammy, blackpill-f401cc)	34s
build-msvc (meson, windows-2022)	1m 15s
build-macos (macos-14, gcc@11)	51s
build-mingw (windows-2022, clang64)	1m 56s
build-linux (jammy, blackpill-f401ce)	37s
build-macos (macos-14, gcc@12)	42s
build-linux (jammy, blackpill-f411ce)	36s
build-macos (macos-14, gcc@13)	34s
build-linux (jammy, bluepill)	38s
size-diff	53s
build-macos (macos-14, gcc@14)	32s
build-linux (jammy, ctxlink)	32s
build-linux (jammy, f072)	33s
build-linux (jammy, f3)	32s
build-linux (jammy, f4discovery)	38s
build-linux (jammy, hydrabus)	39s
build-linux (jammy, launchpad-icdi)	36s
build-linux (jammy, native)	41s
build-linux (jammy, native-uncommon)	30s
build-linux (jammy, native-st-clones)	35s
build-linux (jammy, native-riscv)	31s
build-linux (jammy, native-remote)	37s
build-linux (jammy, stlink)	37s
build-linux (jammy, stlinkv3)	34s
build-linux (jammy, swlink)	33s
	28m 4s

Provide feedback