RISC-V: Clarify the behavior of .option rvc or norvc.
Add/Remove the rvc extension to/from the riscv_subsets once the
.option rvc/norvc is set. So that we don't need to always check
the riscv_opts.rvc in the riscv_subset_supports, just call the
riscv_lookup_subset to search the subset list is enough.
Besides, we will need to dump the instructions according to the
elf architecture attributes. That means the dis-assembler needs
to parse the architecture string from the elf attribute before
dumping any instructions, and also needs to recognized the
INSN_CLASS* classes from riscv_opcodes. Therefore, I suppose
some functions will need to be moved from gas/config/tc-riscv.c
to bfd/elfxx-riscv.c, including riscv_multi_subset_supports and
riscv_subset_supports. This is one of the reasons why we need
this patch.
This patch passes the gcc/binutils regressions of rv32emc-elf,
rv32i-elf, rv64gc-elf and rv64gc-linux toolchains.
bfd/
* elfxx-riscv.c (riscv_remove_subset): Remove the extension
from the subset list.
(riscv_update_subset): Add/Remove an extension to/from the
subset list. This is used for the .option rvc or norvc.
* elfxx-riscv.h: Added the extern bool riscv_update_subset.
gas/
* config/tc-riscv.c (riscv_set_options): Removed the unused
rve flag.
(riscv_opts): Likewise.
(riscv_set_rve): Removed.
(riscv_subset_supports): Removed the riscv_opts.rvc check.
(riscv_set_arch): Don't need to call riscv_set_rve.
(reg_lookup_internal): Call riscv_subset_supports to check
whether the rve is supported.
(s_riscv_option): Add/Remove the rvc extension to/from the
subset list once the .option rvc/norvc is set.
3 files changed
