[PATCH v2 0/9] RISC-V: Support version controling for ISA standard extensions and CSR

[PATCH v2 0/9] RISC-V: Support version controling for ISA standard extensions and CSR

1. Remove the -mriscv-isa-version and --with-riscv-isa-version options.
We can still use -march to choose the version for each extensions, so there is
no need to add these.

2. Change the arguments of options from [1p9|1p9p1|...] to [1.9|1.9.1|...].
Unlike the architecture string has specified by spec, ther is no need to do
the same thing for options.

3. Spilt the patches to reduce the burdens of review.

[PATCH 3/7] RISC-V: Support new GAS options and configure options to set ISA versions
to
[PATCH v2 3/9] RISC-V: Support GAS option -misa-spec to set ISA versions
[PATCH v2 4/9] RISC-V: Support configure options to set ISA versions by default.

[PATCH 4/7] RISC-V: Support version checking for CSR according to privilege version.
to
[PATCH v2 5/9] RISC-V: Support version checking for CSR according to privilege spec version.
[PATCH v2 6/9] RISC-V: Support configure option to choose the privilege spec version.

4. Use enum class rather than string to compare the choosen ISA spec in opcodes/riscv-opc.c.
The behavior is same as comparing the choosen privilege spec.

include	* opcode/riscv.h: Include "bfd.h" to support bfd_boolean.
	(enum riscv_isa_spec_class): New enum class.  All supported ISA spec
	belong to one of the class
	(struct riscv_ext_version): New structure holds version information
	for the specific ISA.
	* opcode/riscv-opc.h (DECLARE_CSR): There are two version information,
	define_version and abort_version.  The define_version means which
	privilege spec is started to define the CSR, and the abort_version
	means which privilege spec is started to abort the CSR.  If the CSR is
	valid for the newest spec, then the abort_version should be
	PRIV_SPEC_CLASS_DRAFT.
	(DECLARE_CSR_ALIAS): Same as DECLARE_CSR, but only for the obselete CSR.
	* opcode/riscv.h (enum riscv_priv_spec_class): New enum class.  Define
	the current supported privilege spec versions.
	(struct riscv_csr_extra): Add new fields to store more information
	about the CSR.  We use these information to find the suitable CSR
	address when user choosing a specific privilege spec.

binutils * dwarf.c: Updated since DECLARE_CSR is changed.

opcodes	* riscv-opc.c (riscv_ext_version_table): The table used to store
	all information about the supported spec and the corresponding ISA
	versions.  Currently, only Zicsr is supported to verify the
	correctness of Z sub extension settings.  Others will be supported
	in the future patches.
	(struct isa_spec_t, isa_specs): List for all supported ISA spec
	classes and the corresponding strings.
	(riscv_get_isa_spec_class): New function.  Get the corresponding ISA
	spec class by giving a ISA spec string.
	* riscv-opc.c (struct priv_spec_t): New structure.
	(struct priv_spec_t priv_specs): List for all supported privilege spec
	classes and the corresponding strings.
	(riscv_get_priv_spec_class): New function.  Get the corresponding
	privilege spec class by giving a spec string.
	(riscv_get_priv_spec_name): New function.  Get the corresponding
	privilege spec string by giving a CSR version class.
	* riscv-dis.c: Updated since DECLARE_CSR is changed.
	* riscv-dis.c: Add new disassembler option -Mpriv-spec to dump the CSR
	according to the chosen version.  Build a hash table riscv_csr_hash to
	store the valid CSR for the chosen pirv verison.  Dump the direct
	CSR address rather than it's name if it is invalid.
	(parse_riscv_dis_option_without_args): New function.  Parse the options
	without arguments.
	(parse_riscv_dis_option): Call parse_riscv_dis_option_without_args to
	parse the options without arguments first, and then handle the options
	with arguments.  Add the new option -Mpriv-spec, which has argument.
	* riscv-dis.c (print_riscv_disassembler_options): Add description
	about the new OBJDUMP option.

ld	* testsuite/ld-riscv-elf/attr-merge-arch-01.d: Updated
        priv attributes according to the -mpriv-spec option.
	* testsuite/ld-riscv-elf/attr-merge-arch-02.d: Likewise.
	* testsuite/ld-riscv-elf/attr-merge-arch-03.d: Likewise.
	* testsuite/ld-riscv-elf/attr-merge-priv-spec-a.s: Likewise.
	* testsuite/ld-riscv-elf/attr-merge-priv-spec-b.s: Likewise.
	* testsuite/ld-riscv-elf/attr-merge-priv-spec.d: Likewise.
	* testsuite/ld-riscv-elf/attr-merge-stack-align.d: Likewise.
	* testsuite/ld-riscv-elf/attr-merge-strict-align-01.d: Likewise.
	* testsuite/ld-riscv-elf/attr-merge-strict-align-02.d: Likewise.
	* testsuite/ld-riscv-elf/attr-merge-strict-align-03.d: Likewise.
	* testsuite/ld-riscv-elf/attr-merge-strict-align-04.d: Likewise.
	* testsuite/ld-riscv-elf/attr-merge-strict-align-05.d: Likewise.

bfd 	* elfxx-riscv.h (riscv_parse_subset_t): Add new callback function
	get_default_version.  It is used to find the default version for
	the specific extension.
	* elfxx-riscv.c (riscv_parsing_subset_version): Remove the parameters
	default_major_version and default_minor_version.  Add new bfd_boolean
	parameter *use_default_version.  Set it to TRUE if we need to call
	the callback rps->get_default_version to find the default version.
	(riscv_parse_std_ext): Call rps->get_default_version if we fail to find
	the default version in riscv_parsing_subset_version, and then call
	riscv_add_subset to add the subset into subset list.
	(riscv_parse_prefixed_ext): Likewise.
	(riscv_std_z_ext_strtab): Support Zicsr extensions.
	* elfnn-riscv.c (riscv_merge_std_ext): Use strcasecmp to compare the
	strings rather than characters.
	riscv_merge_arch_attr_info): The callback function get_default_version
	is only needed for assembler, so set it to NULL int the linker.
	* elfxx-riscv.c (riscv_estimate_digit): Remove the static.
	* elfxx-riscv.h: Updated.

gas	* testsuite/gas/riscv/priv-reg-fail-read-only-01.s: Updated.
	* config/tc-riscv.c (default_arch_with_ext, default_isa_spec):
	Static variables which are used to set the ISA extensions. You can
	use -march (or ELF build attributes) and -misa-spec to set them,
	respectively.
	(ext_version_hash): The hash table used to handle the extensions
	with versions.
	(init_ext_version_hash): Initialize the ext_version_hash according
	to riscv_ext_version_table.
	(riscv_get_default_ext_version): The callback function of
	riscv_parse_subset_t.  According to the choosed ISA spec,
	get the default version for the specific extension.
	(riscv_set_arch): Set the callback function.
	(enum options, struct option md_longopts): Add new option -misa-spec.
	(md_parse_option): Do not call riscv_set_arch for -march.  We will
	call it later in riscv_after_parse_args.  Call riscv_get_isa_spec_class
	to set default_isa_spec class.
	(riscv_after_parse_args): Call init_ext_version_hash to initialize the
	ext_version_hash, and then call riscv_set_arch to set the architecture
	with versions according to default_arch_with_ext.
	* testsuite/gas/riscv/attribute-02.d: Set 0p0 as default version for
	x extensions.
	* testsuite/gas/riscv/attribute-03.d: Likewise.
	* testsuite/gas/riscv/attribute-09.d: New testcase.  For i-ext, we
	already set it's version to 2p1 by march, so no need to use the default
	2p2 version.  For m-ext, we do not set the version by -march and ELF arch
	attribute, so set the default 2p0 to it.  For zicsr, it is not defined in
	ISA spec 2p2, so set 0p0 to it.
	* testsuite/gas/riscv/attribute-10.d: New testcase.  The version of
	zicsr is 2p0 according to ISA spec 20191213.
	* config/tc-riscv.c (DEFAULT_RISCV_ARCH_WITH_EXT)
	(DEFAULT_RISCV_ISA_SPEC): Default configure option settings.
	You can set them by configure options --with-arch and
	--with-isa-spec, respectively.
	(riscv_set_default_isa_spec): New function used to set the
	default ISA spec.
	(md_parse_option): Call riscv_set_default_isa_spec rather than
	call riscv_get_isa_spec_class directly.
	(riscv_after_parse_args): If the -isa-spec is not set, then we
	set the default ISA spec according to DEFAULT_RISCV_ISA_SPEC by
	calling riscv_set_default_isa_spec.
	* testsuite/gas/riscv/attribute-01.d: Add -misa-spec=2.2, since
	the --with-isa-spec may be set to different ISA spec.
	* testsuite/gas/riscv/attribute-02.d: Likewise.
	* testsuite/gas/riscv/attribute-03.d: Likewise.
	* testsuite/gas/riscv/attribute-04.d: Likewise.
	* testsuite/gas/riscv/attribute-05.d: Likewise.
	* testsuite/gas/riscv/attribute-06.d: Likewise.
	* testsuite/gas/riscv/attribute-07.d: Likewise.
	* configure.ac: Add configure options, --with-arch and
	--with-isa-spec.
	* configure: Regenerated.
	* config.in: Regenerated.
	* config/tc-riscv.c (default_priv_spec): Static variable which is
	used to check if the CSR is valid for the chosen privilege spec. You
	can use -mpriv-spec to set it.
	(enum reg_class): We now get the CSR address from csr_extra_hash rather
	than reg_names_hash.  Therefore, move RCLASS_CSR behind RCLASS_MAX.
	(riscv_init_csr_hashes): Only need to initialize one hash table
	csr_extra_hash.
	(riscv_csr_class_check): Change the return type to void.  Don't check
	the ISA dependency if -mcsr-check isn't set.
	(riscv_csr_version_check): New function.  Check and find the CSR address
	from csr_extra_hash, according to default_priv_spec.  Report warning
	for the invalid CSR if -mcsr-check is set.
	(reg_csr_lookup_internal): Updated.
	(reg_lookup_internal): Likewise.
	(md_begin): Updated since DECLARE_CSR and DECLARE_CSR_ALIAS are changed.
	(enum options, struct option md_longopts): Add new GAS option -mpriv-spec.
	(md_parse_option): Call riscv_set_default_priv_version to set
	default_priv_spec.
	(riscv_after_parse_args): If -mpriv-spec isn't set, then set the default
	privilege spec to the newest one.
	(enum riscv_csr_class, struct riscv_csr_extra): Move them to
	include/opcode/riscv.h.
	* testsuite/gas/riscv/priv-reg-fail-fext.d: This test case just want
	to check the ISA dependency for CSR, so fix the spec version by adding
	-mpriv-spec=1.11.
	* testsuite/gas/riscv/priv-reg-fail-fext.l: Likewise.  There are some
	version warnings for the test case.
	* gas/testsuite/gas/riscv/priv-reg-fail-read-only-01.d: Likewise.
	* gas/testsuite/gas/riscv/priv-reg-fail-read-only-01.l: Likewise.
	* gas/testsuite/gas/riscv/priv-reg-fail-read-only-02.d: Likewise.
	* gas/testsuite/gas/riscv/priv-reg-fail-rv32-only.d: Likewise.
	* gas/testsuite/gas/riscv/priv-reg-fail-rv32-only.l: Likewise.
	* gas/testsuite/gas/riscv/priv-reg-fail-version-1p9.d: New test case.
	Check whether the CSR is valid when privilege version 1.9 is choosed.
	* gas/testsuite/gas/riscv/priv-reg-fail-version-1p9.l: Likewise.
	* gas/testsuite/gas/riscv/priv-reg-fail-version-1p9p1.d: New test case.
	Check whether the CSR is valid when privilege version 1.9.1 is choosed.
	* gas/testsuite/gas/riscv/priv-reg-fail-version-1p9p1.l: Likewise.
	* gas/testsuite/gas/riscv/priv-reg-fail-version-1p10.d: New test case.
	Check whether the CSR is valid when privilege version 1.10 is choosed.
	* gas/testsuite/gas/riscv/priv-reg-fail-version-1p10.l: Likewise.
	* gas/testsuite/gas/riscv/priv-reg-fail-version-1p11.d: New test case.
	Check whether the CSR is valid when privilege version 1.11 is choosed.
	* gas/testsuite/gas/riscv/priv-reg-fail-version-1p11.l: Likewise.
	* config/tc-riscv.c (DEFAULT_RISCV_ISA_SPEC): Default configure option
	setting.  You can set it by configure option --with-priv-spec.
	(riscv_set_default_priv_spec): New function used to set the default
	privilege spec.
	(md_parse_option): Call riscv_set_default_priv_spec rather than
	call riscv_get_priv_spec_class directly.
	(riscv_after_parse_args): If -mpriv-spec isn't set, then we set the
	default privilege spec according to DEFAULT_RISCV_PRIV_SPEC by
	calling riscv_set_default_priv_spec.
	* testsuite/gas/riscv/csr-dw-regnums.d: Add -mpriv-spec=1.11, since
	the --with-priv-spec may be set to different privilege spec.
	* testsuite/gas/riscv/priv-reg.d: Likewise.
	* configure.ac: Add configure option --with-priv-spec.
	* configure: Regenerated.
	* config.in: Regenerated.
	* config/tc-riscv.c (explicit_attr): Rename explicit_arch_attr to
	explicit_attr.  Set it to TRUE if any ELF attribute is found.
	(riscv_set_default_priv_spec): Try to set the default_priv_spec if
	the priv attributes are set.
	(md_assemble): Set the default_priv_spec according to the priv
	attributes when we start to assemble instruction.
	(riscv_write_out_attrs): Rename riscv_write_out_arch_attr to
	riscv_write_out_attrs.  Update the arch and priv attributes.  If we
	don't set the corresponding ELF attributes, then try to output the
	default ones.
	(riscv_set_public_attributes): If any ELF attribute or -march-attr
	options is set (explicit_attr is TRUE), then call riscv_write_out_attrs
	to update the arch and priv attributes.
	(s_riscv_attribute): Make sure all arch and priv attributes are set
	before any instruction.
	* testsuite/gas/riscv/attribute-01.d: Update the priv attributes if any
	ELF attribute or -march-attr is set.  If the priv attributes are not
	set, then try to update them by the default setting (-mpriv-spec or
	--with-priv-spec).
	* testsuite/gas/riscv/attribute-02.d: Likewise.
	* testsuite/gas/riscv/attribute-03.d: Likewise.
	* testsuite/gas/riscv/attribute-04.d: Likewise.
	* testsuite/gas/riscv/attribute-06.d: Likewise.
	* testsuite/gas/riscv/attribute-07.d: Likewise.
	* testsuite/gas/riscv/attribute-08.d: Likewise.
	* testsuite/gas/riscv/attribute-09.d: Likewise.
	* testsuite/gas/riscv/attribute-10.d: Likewise.
	* testsuite/gas/riscv/attribute-unknown.d: Likewise.
	* testsuite/gas/riscv/attribute-05.d: Likewise.  Also, the priv spec
	set by priv attributes must be supported.
	* testsuite/gas/riscv/attribute-05.s: Likewise.
	* testsuite/gas/riscv/priv-reg-fail-version-1p9.d: Likewise.  Updated
	priv attributes according to the -mpriv-spec option.
	* testsuite/gas/riscv/priv-reg-fail-version-1p9p1.d: Likewise.
	* testsuite/gas/riscv/priv-reg-fail-version-1p10.d: Likewise.
	* testsuite/gas/riscv/priv-reg-fail-version-1p11.d: Likewise.
	* testsuite/gas/riscv/priv-reg.d: Removed.
	* testsuite/gas/riscv/priv-reg-version-1p9.d: New test case.  Dump the
	CSR according to the priv spec 1.9.
	* testsuite/gas/riscv/priv-reg-version-1p9p1.d: New test case.  Dump the
	CSR according to the priv spec 1.9.1.
	* testsuite/gas/riscv/priv-reg-version-1p10.d: New test case.  Dump the
	CSR according to the priv spec 1.10.
	* testsuite/gas/riscv/priv-reg-version-1p11.d: New test case.  Dump the
	CSR according to the priv spec 1.11.
	* config/tc-riscv.c (md_show_usage): Add descriptions about
	the new GAS options.
	* doc/c-riscv.texi: Likewise.