[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.

1 files changed, 166 insertions, 119 deletions

diff --git a/bfd/elfxx-riscv.c b/bfd/elfxx-riscv.c
index b15fdee..5dd36ab 100644
--- a/bfd/elfxx-riscv.c
+++ b/bfd/elfxx-riscv.c
@@ -1025,9 +1025,8 @@ riscv_elf_add_sub_reloc (bfd *abfd,
      `minor_version`: Parsing result of minor version, set to 0 if version is
      not present in arch string, but set to `default_minor_version` if
      `major_version` using default_major_version.
-     `default_major_version`: Default major version.
-     `default_minor_version`: Default minor version.
-     `std_ext_p`: True if parsing std extension.  */
+     `std_ext_p`: True if parsing std extension.
+     `use_default_version`: Set it to True if we need the default version.  */
 
 static const char *
 riscv_parsing_subset_version (riscv_parse_subset_t *rps,
@@ -1035,17 +1034,16 @@ riscv_parsing_subset_version (riscv_parse_subset_t *rps,
 			      const char *p,
 			      unsigned *major_version,
 			      unsigned *minor_version,
-			      unsigned default_major_version,
-			      unsigned default_minor_version,
-			      bfd_boolean std_ext_p)
+			      bfd_boolean std_ext_p,
+			      bfd_boolean *use_default_version)
 {
   bfd_boolean major_p = TRUE;
   unsigned version = 0;
-  unsigned major = 0;
-  unsigned minor = 0;
   char np;
 
-  for (;*p; ++p)
+  *major_version = 0;
+  *minor_version = 0;
+  for (; *p; ++p)
     {
       if (*p == 'p')
 	{
@@ -1062,13 +1060,14 @@ riscv_parsing_subset_version (riscv_parse_subset_t *rps,
 		}
 	      else
 		{
-		  rps->error_handler ("-march=%s: Expect number after `%dp'.",
-				      march, version);
+		  rps->error_handler
+		    (_("-march=%s: Expect number after `%dp'."),
+		     march, version);
 		  return NULL;
 		}
 	    }
 
-	  major = version;
+	  *major_version = version;
 	  major_p = FALSE;
 	  version = 0;
 	}
@@ -1079,21 +1078,15 @@ riscv_parsing_subset_version (riscv_parse_subset_t *rps,
     }
 
   if (major_p)
-    major = version;
+    *major_version = version;
   else
-    minor = version;
+    *minor_version = version;
 
-  if (major == 0 && minor == 0)
-    {
-      /* We don't found any version string, use default version.  */
-      *major_version = default_major_version;
-      *minor_version = default_minor_version;
-    }
-  else
-    {
-      *major_version = major;
-      *minor_version = minor;
-    }
+  /* We can not find any version in string, need to parse default version.  */
+  if (use_default_version != NULL
+      && *major_version == 0
+      && *minor_version == 0)
+    *use_default_version = TRUE;
   return p;
 }
 
@@ -1118,78 +1111,114 @@ riscv_supported_std_ext (void)
 
 static const char *
 riscv_parse_std_ext (riscv_parse_subset_t *rps,
-		     const char *march, const char *p)
+		     const char *march,
+		     const char *p)
 {
   const char *all_std_exts = riscv_supported_std_ext ();
   const char *std_exts = all_std_exts;
-
   unsigned major_version = 0;
   unsigned minor_version = 0;
   char std_ext = '\0';
+  bfd_boolean use_default_version = FALSE;
 
   /* First letter must start with i, e or g.  */
   switch (*p)
     {
       case 'i':
-	p++;
-	p = riscv_parsing_subset_version (
-	      rps,
-	      march,
-	      p, &major_version, &minor_version,
-	      /* default_major_version= */ 2,
-	      /* default_minor_version= */ 0,
-	      /* std_ext_p= */TRUE);
-	riscv_add_subset (rps->subset_list, "i", major_version, minor_version);
+	p = riscv_parsing_subset_version (rps,
+					  march,
+					  ++p,
+					  &major_version,
+					  &minor_version,
+					  /* std_ext_p= */TRUE,
+					  &use_default_version);
+
+	/* Find the default version if needed.  */
+	if (use_default_version
+	    && rps->get_default_version != NULL)
+	  rps->get_default_version ("i",
+				    &major_version,
+				    &minor_version);
+	riscv_add_subset (rps->subset_list, "i",
+			  major_version, minor_version);
 	break;
 
       case 'e':
-	p++;
-	p = riscv_parsing_subset_version (
-	      rps,
-	      march,
-	      p, &major_version, &minor_version,
-	      /* default_major_version= */ 1,
-	      /* default_minor_version= */ 9,
-	      /* std_ext_p= */TRUE);
-
-	riscv_add_subset (rps->subset_list, "e", major_version, minor_version);
-	riscv_add_subset (rps->subset_list, "i", 2, 0);
+	p = riscv_parsing_subset_version (rps,
+					  march,
+					  ++p,
+					  &major_version,
+					  &minor_version,
+					  /* std_ext_p= */TRUE,
+					  &use_default_version);
+
+	/* Find the default version if needed.  */
+	if (use_default_version
+	    && rps->get_default_version != NULL)
+	  rps->get_default_version ("e",
+				    &major_version,
+				    &minor_version);
+	riscv_add_subset (rps->subset_list, "e",
+			  major_version, minor_version);
+
+	/* i-ext must be enabled.  */
+	if (rps->get_default_version != NULL)
+	  rps->get_default_version ("i",
+				    &major_version,
+				    &minor_version);
+	riscv_add_subset (rps->subset_list, "i",
+			  major_version, minor_version);
 
 	if (*rps->xlen > 32)
 	  {
-	    rps->error_handler ("-march=%s: rv%de is not a valid base ISA",
-				march, *rps->xlen);
+	    rps->error_handler
+	      (_("-march=%s: rv%de is not a valid base ISA"),
+	       march, *rps->xlen);
 	    return NULL;
 	  }
-
 	break;
 
       case 'g':
-	p++;
-	p = riscv_parsing_subset_version (
-	      rps,
-	      march,
-	      p, &major_version, &minor_version,
-	      /* default_major_version= */ 2,
-	      /* default_minor_version= */ 0,
-	      /* std_ext_p= */TRUE);
-	riscv_add_subset (rps->subset_list, "i", major_version, minor_version);
+	/* The g-ext shouldn't has the version, so we just
+	   skip the setting if user set a version to it.  */
+	p = riscv_parsing_subset_version (rps,
+					  march,
+					  ++p,
+					  &major_version,
+					  &minor_version,
+					  TRUE,
+					  &use_default_version);
+
+	/* i-ext must be enabled.  */
+	if (rps->get_default_version != NULL)
+	  rps->get_default_version ("i",
+				    &major_version,
+				    &minor_version);
+	riscv_add_subset (rps->subset_list, "i",
+			  major_version, minor_version);
 
 	for ( ; *std_exts != 'q'; std_exts++)
 	  {
 	    const char subset[] = {*std_exts, '\0'};
-	    riscv_add_subset (
-	      rps->subset_list, subset, major_version, minor_version);
+
+	    if (rps->get_default_version != NULL)
+	      rps->get_default_version (subset,
+					&major_version,
+					&minor_version);
+	    riscv_add_subset (rps->subset_list, subset,
+			      major_version, minor_version);
 	  }
 	break;
 
       default:
-	rps->error_handler (
-	  "-march=%s: first ISA subset must be `e', `i' or `g'", march);
+	rps->error_handler
+	  (_("-march=%s: first ISA subset must be `e', `i' or `g'"), march);
 	return NULL;
     }
 
-  while (*p)
+  /* The riscv_parsing_subset_version may set `p` to NULL, so I think we should
+     skip parsing the string if `p` is NULL or value of `p` is `\0`.  */
+  while (p != NULL && *p != '\0')
     {
       char subset[2] = {0, 0};
 
@@ -1210,29 +1239,35 @@ riscv_parse_std_ext (riscv_parse_subset_t *rps,
       if (std_ext != *std_exts)
 	{
 	  if (strchr (all_std_exts, std_ext) == NULL)
-	    rps->error_handler (
-	      "-march=%s: unsupported ISA subset `%c'", march, *p);
+	    rps->error_handler
+	      (_("-march=%s: unsupported ISA subset `%c'"), march, *p);
 	  else
-	    rps->error_handler (
-	      "-march=%s: ISA string is not in canonical order. `%c'",
-	      march, *p);
+	    rps->error_handler
+	      (_("-march=%s: ISA string is not in canonical order. `%c'"),
+	       march, *p);
 	  return NULL;
 	}
 
       std_exts++;
 
-      p++;
-      p = riscv_parsing_subset_version (
-	    rps,
-	    march,
-	    p, &major_version, &minor_version,
-	    /* default_major_version= */ 2,
-	    /* default_minor_version= */ 0,
-	    /* std_ext_p= */TRUE);
-
+      use_default_version = FALSE;
       subset[0] = std_ext;
-
-      riscv_add_subset (rps->subset_list, subset, major_version, minor_version);
+      p = riscv_parsing_subset_version (rps,
+					march,
+					++p,
+					&major_version,
+					&minor_version,
+					TRUE,
+					&use_default_version);
+
+      /* Find the default version if needed.  */
+      if (use_default_version
+	  && rps->get_default_version != NULL)
+	rps->get_default_version (subset,
+				  &major_version,
+				  &minor_version);
+      riscv_add_subset (rps->subset_list, subset,
+			major_version, minor_version);
     }
   return p;
 }
@@ -1272,9 +1307,10 @@ typedef struct riscv_parse_config
 } riscv_parse_config_t;
 
 /* Parse a generic prefixed extension.
-   march: The full architecture string as passed in by "-march=...".
-   p: Point from which to start parsing the -march string.
-   config: What class of extensions to parse, predicate funcs,
+   `rps`: Hooks and status for parsing subset.
+   `march`: The full architecture string as passed in by "-march=...".
+   `p`: Point from which to start parsing the -march string.
+   `config`: What class of extensions to parse, predicate funcs,
    and strings to use in error reporting.  */
 
 static const char *
@@ -1287,6 +1323,7 @@ riscv_parse_prefixed_ext (riscv_parse_subset_t *rps,
   unsigned minor_version = 0;
   const char *last_name;
   riscv_isa_ext_class_t class;
+  bfd_boolean use_default_version;
 
   while (*p)
     {
@@ -1309,15 +1346,11 @@ riscv_parse_prefixed_ext (riscv_parse_subset_t *rps,
       while (*++q != '\0' && *q != '_' && !ISDIGIT (*q))
 	;
 
+      use_default_version = FALSE;
       end_of_version =
-	riscv_parsing_subset_version (
-	  rps,
-	  march,
-	  q, &major_version, &minor_version,
-	  /* default_major_version= */ 2,
-	  /* default_minor_version= */ 0,
-	  /* std_ext_p= */FALSE);
-
+	riscv_parsing_subset_version (rps, march, q, &major_version,
+				      &minor_version, FALSE,
+				      &use_default_version);
       *q = '\0';
 
       /* Check that the name is valid.
@@ -1329,7 +1362,7 @@ riscv_parse_prefixed_ext (riscv_parse_subset_t *rps,
       if (!config->ext_valid_p (subset))
 	{
 	  rps->error_handler
-	    ("-march=%s: Invalid or unknown %s ISA extension: '%s'",
+	    (_("-march=%s: Invalid or unknown %s ISA extension: '%s'"),
 	     march, config->prefix, subset);
 	  free (subset);
 	  return NULL;
@@ -1337,11 +1370,11 @@ riscv_parse_prefixed_ext (riscv_parse_subset_t *rps,
 
       /* Check that the last item is not the same as this.  */
       last_name = rps->subset_list->tail->name;
-
       if (!strcasecmp (last_name, subset))
 	{
-	  rps->error_handler ("-march=%s: Duplicate %s ISA extension: \'%s\'",
-			      march, config->prefix, subset);
+	  rps->error_handler
+	    (_("-march=%s: Duplicate %s ISA extension: \'%s\'"),
+	     march, config->prefix, subset);
 	  free (subset);
 	  return NULL;
 	}
@@ -1350,20 +1383,29 @@ riscv_parse_prefixed_ext (riscv_parse_subset_t *rps,
       if (!strncasecmp (last_name, config->prefix, 1)
 	  && strcasecmp (last_name, subset) > 0)
 	{
-	  rps->error_handler ("-march=%s: %s ISA extension not in alphabetical "
-			      "order: \'%s\' must come before \'%s\'.",
-			      march, config->prefix, subset, last_name);
+	  rps->error_handler
+	    (_("\
+-march=%s: %s ISA extension not in alphabetical order: \'%s\' must come before \'%s\'."),
+	     march, config->prefix, subset, last_name);
 	  free (subset);
 	  return NULL;
 	}
 
-      riscv_add_subset (rps->subset_list, subset, major_version, minor_version);
+      /* Find the default version if needed.  */
+      if (use_default_version
+         && rps->get_default_version != NULL)
+       rps->get_default_version (subset,
+                                 &major_version,
+                                 &minor_version);
+      riscv_add_subset (rps->subset_list, subset,
+                       major_version, minor_version);
+
       free (subset);
       p += end_of_version - subset;
 
       if (*p != '\0' && *p != '_')
 	{
-	  rps->error_handler ("-march=%s: %s must separate with _",
+	  rps->error_handler (_("-march=%s: %s must separate with _"),
 			      march, config->prefix);
 	  return NULL;
 	}
@@ -1384,7 +1426,7 @@ riscv_parse_prefixed_ext (riscv_parse_subset_t *rps,
 
 static const char * const riscv_std_z_ext_strtab[] =
   {
-    NULL
+    "zicsr", NULL
   };
 
 /* Same as `riscv_std_z_ext_strtab', but for S-class extensions.  */
@@ -1478,8 +1520,9 @@ riscv_parse_subset (riscv_parse_subset_t *rps,
     }
   else
     {
-      rps->error_handler ("-march=%s: ISA string must begin with rv32 or rv64",
-			  arch);
+      rps->error_handler
+	(_("-march=%s: ISA string must begin with rv32 or rv64"),
+	 arch);
       return FALSE;
     }
 
@@ -1490,7 +1533,6 @@ riscv_parse_subset (riscv_parse_subset_t *rps,
     return FALSE;
 
   /* Parse the different classes of extensions in the specified order.  */
-
   for (i = 0; i < ARRAY_SIZE (parse_config); ++i) {
     p = riscv_parse_prefixed_ext (rps, arch, p, &parse_config[i]);
 
@@ -1500,7 +1542,7 @@ riscv_parse_subset (riscv_parse_subset_t *rps,
 
   if (*p != '\0')
     {
-      rps->error_handler ("-march=%s: unexpected ISA string at end: %s",
+      rps->error_handler (_("-march=%s: unexpected ISA string at end: %s"),
 			  arch, p);
       return FALSE;
     }
@@ -1508,31 +1550,35 @@ riscv_parse_subset (riscv_parse_subset_t *rps,
   if (riscv_lookup_subset (rps->subset_list, "e")
       && riscv_lookup_subset (rps->subset_list, "f"))
     {
-      rps->error_handler ("-march=%s: rv32e does not support the `f' extension",
-			  arch);
+      rps->error_handler
+	(_("-march=%s: rv32e does not support the `f' extension"),
+	 arch);
       return FALSE;
     }
 
   if (riscv_lookup_subset (rps->subset_list, "d")
       && !riscv_lookup_subset (rps->subset_list, "f"))
     {
-      rps->error_handler ("-march=%s: `d' extension requires `f' extension",
-			  arch);
+      rps->error_handler
+	(_("-march=%s: `d' extension requires `f' extension"),
+	 arch);
       return FALSE;
     }
 
   if (riscv_lookup_subset (rps->subset_list, "q")
       && !riscv_lookup_subset (rps->subset_list, "d"))
     {
-      rps->error_handler ("-march=%s: `q' extension requires `d' extension",
-			  arch);
+      rps->error_handler
+	(_("-march=%s: `q' extension requires `d' extension"),
+	 arch);
       return FALSE;
     }
 
   if (riscv_lookup_subset (rps->subset_list, "q") && *rps->xlen < 64)
     {
-      rps->error_handler ("-march=%s: rv32 does not support the `q' extension",
-			  arch);
+      rps->error_handler
+	(_("-march=%s: rv32 does not support the `q' extension"),
+	 arch);
       return FALSE;
     }
   return TRUE;
@@ -1543,7 +1589,8 @@ riscv_parse_subset (riscv_parse_subset_t *rps,
 void
 riscv_add_subset (riscv_subset_list_t *subset_list,
 		  const char *subset,
-		  int major, int minor)
+		  int major,
+		  int minor)
 {
   riscv_subset_t *s = xmalloc (sizeof *s);
 
@@ -1567,10 +1614,10 @@ riscv_subset_t *
 riscv_lookup_subset (const riscv_subset_list_t *subset_list,
 		     const char *subset)
 {
-  return riscv_lookup_subset_version (
-	   subset_list, subset,
-	   RISCV_DONT_CARE_VERSION,
-	   RISCV_DONT_CARE_VERSION);
+  return riscv_lookup_subset_version
+    (subset_list, subset,
+     RISCV_DONT_CARE_VERSION,
+     RISCV_DONT_CARE_VERSION);
 }
 
 /* Find subset in list with version checking, return NULL if not found.  */
@@ -1617,7 +1664,7 @@ riscv_release_subset_list (riscv_subset_list_t *subset_list)
 
 /* Return the number of digits for the input.  */
 
-static size_t
+size_t
 riscv_estimate_digit (unsigned num)
 {
   size_t digit = 0;