@@ -18,6 +18,7 @@ along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#include <sstream>
+#include <vector>
#define INCLUDE_STRING
#include "config.h"
@@ -122,6 +123,26 @@ const riscv_subset_list *riscv_current_subset_list ()
return current_subset_list;
}
+/* struct for recording multi-lib info. */
+struct riscv_multi_lib_info_t {
+ std::string path;
+ std::string arch_str;
+ std::string abi_str;
+ std::vector<std::string> conds;
+ riscv_subset_list *subset_list;
+
+ static bool parse (struct riscv_multi_lib_info_t *,
+ const std::string &,
+ const std::vector<std::string> &);
+};
+
+/* Flag for checking if there is no suitable multi-lib found. */
+static bool riscv_no_matched_multi_lib;
+
+/* Used for record value of -march and -mabi. */
+static std::string riscv_current_arch_str;
+static std::string riscv_current_abi_str;
+
riscv_subset_t::riscv_subset_t ()
: name (), major_version (0), minor_version (0), next (NULL),
explicit_version_p (false), implied_p (false)
@@ -147,6 +168,42 @@ riscv_subset_list::~riscv_subset_list ()
}
}
+/* Compute the match score of two arch string, return 0 if incompatible. */
+int
+riscv_subset_list::match_score (riscv_subset_list *list) const
+{
+ riscv_subset_t *s;
+ int score = 0;
+ bool has_a_ext, list_has_a_ext;
+
+ /* Impossible to match if XLEN is different. */
+ if (list->m_xlen != this->m_xlen)
+ return 0;
+
+ /* There is different code gen in libstdc++ and libatomic between w/ A-ext
+ and w/o A-ext, and it not work if using soft and hard atomic mechanism
+ at same time, so they are incompatible. */
+ has_a_ext = this->lookup ("a") != NULL;
+ list_has_a_ext = list->lookup ("a") != NULL;
+
+ if (has_a_ext != list_has_a_ext)
+ return 0;
+
+
+ /* list must be subset of current this list, otherwise it not safe to
+ link.
+ TODO: We might give different weight for each extension, but the rule could
+ be complicated.
+ TODO: We might consider the version of each extension. */
+ for (s = list->m_head; s != NULL; s = s->next)
+ if (this->lookup (s->name.c_str ()) != NULL)
+ score++;
+ else
+ return 0;
+
+ return score;
+}
+
/* Get the rank for single-letter subsets, lower value meaning higher
priority. */
@@ -1054,6 +1111,326 @@ riscv_expand_arch_from_cpu (int argc ATTRIBUTE_UNUSED,
return xasprintf ("-march=%s", arch.c_str());
}
+/* Find last switch with the prefix, options are take last one in general,
+ return NULL if not found, and return the option value if found, it could
+ return empty string if the option has no value. */
+
+static const char *
+find_last_appear_switch (
+ const struct switchstr *switches,
+ int n_switches,
+ const char *prefix)
+{
+ int i;
+ size_t len = strlen (prefix);
+
+ for (i = 0; i < n_switches; ++i)
+ {
+ const struct switchstr *this_switch = &switches[n_switches - i - 1];
+
+ if (this_switch->live_cond & SWITCH_FALSE)
+ continue;
+
+ if (strncmp (this_switch->part1, prefix, len) == 0)
+ return this_switch->part1 + len;
+ }
+
+ return NULL;
+}
+
+/* Utils functions to check STR is start with PREFIX or not. */
+
+static bool
+prefixed_with (const std::string &str, const char *prefix)
+{
+ return strncmp (prefix, str.c_str (), strlen (prefix)) == 0;
+}
+
+/* Parse the path and cond string into riscv_multi_lib_info_t, return false
+ if parsing failed. */
+
+bool
+riscv_multi_lib_info_t::parse (
+ struct riscv_multi_lib_info_t *multi_lib_info,
+ const std::string &path,
+ const std::vector<std::string> &conds)
+{
+ const char *default_arch_str = STRINGIZING (TARGET_RISCV_DEFAULT_ARCH);
+ const char *default_abi_str = STRINGIZING (TARGET_RISCV_DEFAULT_ABI);
+ multi_lib_info->conds = conds;
+ if (path == ".")
+ {
+ multi_lib_info->arch_str = default_arch_str;
+ multi_lib_info->abi_str = default_abi_str;
+ }
+ else
+ {
+ std::vector<std::string>::const_iterator itr;
+ for (itr = conds.begin (); itr != conds.end (); ++itr)
+ if (prefixed_with (*itr, "march="))
+ multi_lib_info->arch_str = itr->c_str () + strlen ("march=");
+ else if (prefixed_with (*itr, "mabi="))
+ multi_lib_info->abi_str = itr->c_str () + strlen ("mabi=");
+
+ /* Skip this multi-lib if this configuration is exactly same as
+ default multi-lib settings. */
+ if (multi_lib_info->arch_str == default_arch_str
+ && multi_lib_info->abi_str == default_abi_str)
+ return false;
+ }
+
+ multi_lib_info->subset_list =
+ riscv_subset_list::parse (multi_lib_info->arch_str.c_str (), input_location);
+
+ return true;
+}
+
+/* Report error if not found suitable multilib. */
+const char *
+riscv_multi_lib_check (int argc ATTRIBUTE_UNUSED,
+ const char **argv ATTRIBUTE_UNUSED)
+{
+ if (riscv_no_matched_multi_lib)
+ fatal_error (
+ input_location,
+ "Can't find suitable multilib set for %<-march=%s%>/%<-mabi=%s%>",
+ riscv_current_arch_str.c_str (),
+ riscv_current_abi_str.c_str ());
+
+ return "";
+}
+
+/* Checking ARG is not appeared in SWITCHES if NOT_ARG is set or
+ ARG is appeared if NOT_ARG is not set. */
+
+static bool
+riscv_check_cond (
+ const struct switchstr *switches,
+ int n_switches,
+ const std::string &arg,
+ bool not_arg)
+{
+ int i;
+ for (i = 0; i < n_switches; ++i)
+ {
+ const struct switchstr *this_switch = &switches[n_switches - i - 1];
+
+ if ((this_switch->live_cond & SWITCH_IGNORE) != 0)
+ continue;
+
+ if (this_switch->live_cond & SWITCH_FALSE)
+ continue;
+
+ /* ARG should not appear if NOT_ARG is set. */
+ if (arg == this_switch->part1)
+ return not_arg ? false : true;
+ }
+
+ /* Not found ARG? that's ok if NOT_ARG is not set. */
+ return not_arg ? true : false;
+}
+
+/* Check the other cond is found or not, return -1 if we should reject this
+ multi-lib option set, otherwise return updated MATCH_SCORE. */
+
+static int
+riscv_check_conds (
+ const struct switchstr *switches,
+ int n_switches,
+ int match_score,
+ const std::vector<std::string> &conds)
+{
+ bool not_arg;
+ bool ok;
+ int ok_count = 0;
+ std::vector<std::string>::const_iterator itr;
+ const char *checking_arg;
+
+ if (match_score == 0)
+ return 0;
+
+ for (itr = conds.begin (); itr != conds.end (); ++itr)
+ {
+ /* We'll check march= and mabi= in ohter place. */
+ if (prefixed_with (*itr, "march=") || prefixed_with (*itr, "mabi="))
+ continue;
+
+ checking_arg = itr->c_str ();
+ if (checking_arg[0] == '!')
+ {
+ not_arg = true;
+ /* Skip '!'. */
+ checking_arg = checking_arg + 1;
+ }
+ else
+ not_arg = false;
+
+ ok = riscv_check_cond (switches, n_switches, checking_arg, not_arg);
+
+ if (!ok)
+ return -1;
+
+ ok_count++;
+ }
+
+ /* 100 is magic number, it's just used for make sure this multi-lib has
+ higher priority if we found any some option is listed in the option check
+ list. */
+ return match_score + ok_count * 100;
+}
+
+/* We only override this in bare-metal toolchain. */
+#ifdef RISCV_USE_CUSTOMISED_MULTI_LIB
+
+/* Implement TARGET_COMPUTE_MULTILIB. */
+static const char *
+riscv_compute_multilib (
+ const struct switchstr *switches,
+ int n_switches,
+ const char *multilib_dir,
+ const char *multilib_defaults ATTRIBUTE_UNUSED,
+ const char *multilib_select,
+ const char *multilib_matches ATTRIBUTE_UNUSED,
+ const char *multilib_exclusions ATTRIBUTE_UNUSED,
+ const char *multilib_reuse ATTRIBUTE_UNUSED)
+{
+ const char *p;
+ const char *this_path;
+ size_t this_path_len;
+ bool result;
+ riscv_no_matched_multi_lib = false;
+ riscv_subset_list *subset_list = NULL;
+
+ std::vector<riscv_multi_lib_info_t> multilib_infos;
+ std::vector<std::string> option_conds;
+ std::string option_cond;
+ riscv_multi_lib_info_t multilib_info;
+
+ /* Already found suitable, multi-lib, just use that. */
+ if (multilib_dir != NULL)
+ return multilib_dir;
+
+ /* Find march. */
+ riscv_current_arch_str =
+ find_last_appear_switch (switches, n_switches, "march=");
+ /* Find mabi. */
+ riscv_current_abi_str =
+ find_last_appear_switch (switches, n_switches, "mabi=");
+
+ /* Failed to find -march or -mabi, but it should not happened since we have
+ set both in OPTION_DEFAULT_SPECS. */
+ if (riscv_current_arch_str.empty () || riscv_current_abi_str.empty ())
+ return multilib_dir;
+
+ subset_list = riscv_subset_list::parse (riscv_current_arch_str.c_str (),
+ input_location);
+
+ /* Failed to parse -march, fallback to using what gcc use. */
+ if (subset_list == NULL)
+ return multilib_dir;
+
+ /* Parsing MULTILIB_SELECT, ignore MULTILIB_REUSE here, we have our own rules.
+ TODO: most codes are grab from gcc.c, maybe we should refine that? */
+ p = multilib_select;
+
+ while (*p != '\0')
+ {
+ /* Ignore newlines. */
+ if (*p == '\n')
+ {
+ ++p;
+ continue;
+ }
+
+ /* Format of each multilib:
+ <path> <opt1> <opt2> ... <optN>; */
+ /* Get the path. */
+ this_path = p;
+ while (*p != ' ')
+ {
+ if (*p == '\0')
+ {
+ fatal_error (input_location, "multilib select %qs %qs is invalid",
+ multilib_select, multilib_reuse);
+ }
+ ++p;
+ }
+
+ this_path_len = p - this_path;
+ multilib_info.path = std::string (this_path, this_path_len);
+
+ option_conds.clear ();
+ /* Pasrse option check list into vector<string>.
+ e.g. "march=rv64imafd mabi=lp64 !mcmodel=medany" to
+ ["march=rv64imafd", "mabi=lp64", "!mcmodel=medany"]. */
+ while (*p != ';')
+ {
+ option_cond = "";
+ /* Skip space. */
+ while (*p == ' ') p++;
+
+ while (*p && *p != ' ' && *p != ';')
+ option_cond.push_back (*p++);
+
+ /* Ignore `!march=` and `!mabi=`, we will handle march and mabi
+ later. */
+ if (option_cond.size ()
+ && !prefixed_with (option_cond, "!march=")
+ && !prefixed_with (option_cond, "!mabi="))
+ option_conds.push_back (option_cond);
+ }
+
+ result =
+ riscv_multi_lib_info_t::parse (
+ &multilib_info,
+ std::string (this_path, this_path_len),
+ option_conds);
+
+ if (result)
+ multilib_infos.push_back (multilib_info);
+
+ p++;
+ }
+
+ int match_score = 0;
+ int max_match_score = 0;
+ int best_match_multi_lib = -1;
+ /* Try to decision which set we should used. */
+ /* We have 3 level decision tree here, ABI, check input arch/ABI must
+ be superset of multi-lib arch, and other rest option checking. */
+ for (size_t i = 0; i < multilib_infos.size (); ++i)
+ {
+ /* Check ABI is same first. */
+ if (riscv_current_abi_str != multilib_infos[i].abi_str)
+ continue;
+
+ /* Found a potential compatible multi-lib setting!
+ Calculate the match score. */
+ match_score = subset_list->match_score (multilib_infos[i].subset_list);
+
+ /* Checking other cond in the multi-lib setting. */
+ match_score = riscv_check_conds (switches,
+ n_switches,
+ match_score,
+ multilib_infos[i].conds);
+
+ /* Record highest match score multi-lib setting. */
+ if (match_score > max_match_score)
+ best_match_multi_lib = i;
+ }
+
+ if (best_match_multi_lib == -1)
+ {
+ riscv_no_matched_multi_lib = true;
+ return multilib_dir;
+ }
+ else
+ return xstrdup (multilib_infos[best_match_multi_lib].path.c_str ());
+}
+
+#undef TARGET_COMPUTE_MULTILIB
+#define TARGET_COMPUTE_MULTILIB riscv_compute_multilib
+#endif
/* Implement TARGET_OPTION_OPTIMIZATION_TABLE. */
static const struct default_options riscv_option_optimization_table[] =
@@ -27,10 +27,14 @@ along with GCC; see the file COPYING3. If not see
/* Link against Newlib libraries, because the ELF backend assumes Newlib.
Handle the circular dependence between libc and libgloss. */
#undef LIB_SPEC
-#define LIB_SPEC "--start-group -lc %{!specs=nosys.specs:-lgloss} --end-group"
+#define LIB_SPEC \
+ "--start-group -lc %{!specs=nosys.specs:-lgloss} --end-group " \
+ "%{!nostartfiles:%{!nodefaultlibs:%{!nolibc:%{!nostdlib:%:riscv_multi_lib_check()}}}}"
#undef STARTFILE_SPEC
#define STARTFILE_SPEC "crt0%O%s crtbegin%O%s"
#undef ENDFILE_SPEC
#define ENDFILE_SPEC "crtend%O%s"
+
+#define RISCV_USE_CUSTOMISED_MULTI_LIB 1
@@ -88,6 +88,8 @@ public:
const riscv_subset_t *begin () const {return m_head;};
const riscv_subset_t *end () const {return NULL;};
+
+ int match_score (riscv_subset_list *) const;
};
extern const riscv_subset_list *riscv_current_subset_list (void);
@@ -50,11 +50,13 @@ along with GCC; see the file COPYING3. If not see
extern const char *riscv_expand_arch (int argc, const char **argv);
extern const char *riscv_expand_arch_from_cpu (int argc, const char **argv);
extern const char *riscv_default_mtune (int argc, const char **argv);
+extern const char *riscv_multi_lib_check (int argc, const char **argv);
# define EXTRA_SPEC_FUNCTIONS \
{ "riscv_expand_arch", riscv_expand_arch }, \
{ "riscv_expand_arch_from_cpu", riscv_expand_arch_from_cpu }, \
- { "riscv_default_mtune", riscv_default_mtune },
+ { "riscv_default_mtune", riscv_default_mtune }, \
+ { "riscv_multi_lib_check", riscv_multi_lib_check },
/* Support for a compile-time default CPU, et cetera. The rules are:
--with-arch is ignored if -march or -mcpu is specified.
Use TARGET_COMPUTE_MULTILIB to search the multi-lib reuse for riscv*-*-elf*, according following rules: 1. Check ABI is same. 2. Check both has atomic extension or both don't have atomic extension. - Because mix soft and hard atomic operation doesn't make sense and won't work as expect. 3. Check current arch is superset of the target multi-lib arch. - It might result slower performance or larger code size, but it safe to run. 4. Pick most match multi-lib set if more than one multi-lib are pass the above checking. Example for how to select multi-lib: We build code with -march=rv32imaf and -mabi=ilp32, and we have following 5 multi-lib set: 1. rv32ia/ilp32 2. rv32ima/ilp32 3. rv32imf/ilp32 4. rv32imaf/ilp32f 5. rv32imafd/ilp32 The first and second multi-lib is safe to like, 3rd multi-lib can't re-use becasue it don't have atomic extension, which is mismatch according rule 2, and the 4th multi-lib can't re-use too due to the ABI mismatch, the last multi-lib can't use since current arch is not superset of the arch of multi-lib. And emit error if not found suitable multi-lib set, the error message only emit when link with standard libraries. Example for when error will be emitted: $ riscv64-unknown-elf-gcc -print-multi-lib .; rv32i/ilp32;@march=rv32i@mabi=ilp32 rv32im/ilp32;@march=rv32im@mabi=ilp32 rv32iac/ilp32;@march=rv32iac@mabi=ilp32 rv32imac/ilp32;@march=rv32imac@mabi=ilp32 rv32imafc/ilp32f;@march=rv32imafc@mabi=ilp32f rv64imac/lp64;@march=rv64imac@mabi=lp64 // No actual linking, so no error emitted. $ riscv64-unknown-elf-gcc -print-multi-directory -march=rv32ia -mabi=ilp32 . // Link to default libc and libgcc, so check the multi-lib, and emit // error because not found suitable multilib. $ riscv64-unknown-elf-gcc -march=rv32ia -mabi=ilp32 ~/hello.c riscv64-unknown-elf-gcc: fatal error: can't found suitable multilib set for '-march=rv32ia'/'-mabi=ilp32' compilation terminated. // No error emitted, because not link to stdlib. $ riscv64-unknown-elf-gcc -march=rv32ia -mabi=ilp32 ~/hello.c -nostdlib // No error emitted, because compile only. $ riscv64-unknown-elf-gcc -march=rv32ia -mabi=ilp32 ~/hello.c -c gcc/ChangeLog: * common/config/riscv/riscv-common.c: Include <vector>. (struct riscv_multi_lib_info_t): New. (riscv_subset_list::match_score): Ditto. (find_last_appear_switch): Ditto. (prefixed_with): Ditto. (struct multi_lib_info_t): Ditto. (riscv_current_arch_str): Ditto. (riscv_current_abi_str): Ditto. (riscv_multi_lib_info_t::parse): Ditto. (riscv_check_cond): Ditto. (riscv_check_conds): Ditto. (riscv_compute_multilib): Ditto. (TARGET_COMPUTE_MULTILIB): Defined. * config/riscv/elf.h (LIB_SPEC): Call riscv_multi_lib_check if doing link. (RISCV_USE_CUSTOMISED_MULTI_LIB): New. * config/riscv/riscv.h (riscv_multi_lib_check): New. (EXTRA_SPEC_FUNCTIONS): Add riscv_multi_lib_check. --- gcc/common/config/riscv/riscv-common.c | 377 +++++++++++++++++++++++++ gcc/config/riscv/elf.h | 6 +- gcc/config/riscv/riscv-subset.h | 2 + gcc/config/riscv/riscv.h | 4 +- 4 files changed, 387 insertions(+), 2 deletions(-)