diff options
Diffstat (limited to 'libctf/ctf-link.c')
| -rw-r--r-- | libctf/ctf-link.c | 321 |
1 files changed, 102 insertions, 219 deletions
diff --git a/libctf/ctf-link.c b/libctf/ctf-link.c index d598b78..c0b0916 100644 --- a/libctf/ctf-link.c +++ b/libctf/ctf-link.c @@ -24,118 +24,18 @@ #pragma weak ctf_open #endif -/* Type tracking machinery. */ - -/* Record the correspondence between a source and ctf_add_type()-added - destination type: both types are translated into parent type IDs if need be, - so they relate to the actual dictionary they are in. Outside controlled - circumstances (like linking) it is probably not useful to do more than - compare these pointers, since there is nothing stopping the user closing the - source dict whenever they want to. - - Our OOM handling here is just to not do anything, because this is called deep - enough in the call stack that doing anything useful is painfully difficult: - the worst consequence if we do OOM is a bit of type duplication anyway. */ - -void -ctf_add_type_mapping (ctf_dict_t *src_fp, ctf_id_t src_type, - ctf_dict_t *dst_fp, ctf_id_t dst_type) -{ - if (LCTF_TYPE_ISPARENT (src_fp, src_type) && src_fp->ctf_parent) - src_fp = src_fp->ctf_parent; - - src_type = LCTF_TYPE_TO_INDEX(src_fp, src_type); - - if (LCTF_TYPE_ISPARENT (dst_fp, dst_type) && dst_fp->ctf_parent) - dst_fp = dst_fp->ctf_parent; - - dst_type = LCTF_TYPE_TO_INDEX(dst_fp, dst_type); - - if (dst_fp->ctf_link_type_mapping == NULL) - { - ctf_hash_fun f = ctf_hash_type_key; - ctf_hash_eq_fun e = ctf_hash_eq_type_key; - - if ((dst_fp->ctf_link_type_mapping = ctf_dynhash_create (f, e, free, - NULL)) == NULL) - return; - } - - ctf_link_type_key_t *key; - key = calloc (1, sizeof (struct ctf_link_type_key)); - if (!key) - return; - - key->cltk_fp = src_fp; - key->cltk_idx = src_type; - - /* No OOM checking needed, because if this doesn't work the worst we'll do is - add a few more duplicate types (which will probably run out of memory - anyway). */ - ctf_dynhash_insert (dst_fp->ctf_link_type_mapping, key, - (void *) (uintptr_t) dst_type); -} - -/* Look up a type mapping: return 0 if none. The DST_FP is modified to point to - the parent if need be. The ID returned is from the dst_fp's perspective. */ -ctf_id_t -ctf_type_mapping (ctf_dict_t *src_fp, ctf_id_t src_type, ctf_dict_t **dst_fp) -{ - ctf_link_type_key_t key; - ctf_dict_t *target_fp = *dst_fp; - ctf_id_t dst_type = 0; - - if (LCTF_TYPE_ISPARENT (src_fp, src_type) && src_fp->ctf_parent) - src_fp = src_fp->ctf_parent; - - src_type = LCTF_TYPE_TO_INDEX(src_fp, src_type); - key.cltk_fp = src_fp; - key.cltk_idx = src_type; - - if (target_fp->ctf_link_type_mapping) - dst_type = (uintptr_t) ctf_dynhash_lookup (target_fp->ctf_link_type_mapping, - &key); - - if (dst_type != 0) - { - dst_type = LCTF_INDEX_TO_TYPE (target_fp, dst_type, - target_fp->ctf_parent != NULL); - *dst_fp = target_fp; - return dst_type; - } - - if (target_fp->ctf_parent) - target_fp = target_fp->ctf_parent; - else - return 0; - - if (target_fp->ctf_link_type_mapping) - dst_type = (uintptr_t) ctf_dynhash_lookup (target_fp->ctf_link_type_mapping, - &key); - - if (dst_type) - dst_type = LCTF_INDEX_TO_TYPE (target_fp, dst_type, - target_fp->ctf_parent != NULL); - - *dst_fp = target_fp; - return dst_type; -} - -/* Linker machinery. - - CTF linking consists of adding CTF archives full of content to be merged into +/* CTF linking consists of adding CTF archives full of content to be merged into this one to the current file (which must be writable) by calling - ctf_link_add_ctf(). Once this is done, a call to ctf_link() will merge the - type tables together, generating new CTF files as needed, with this one as a - parent, to contain types from the inputs which conflict. - ctf_link_add_strtab() takes a callback which provides string/offset pairs to - be added to the external symbol table and deduplicated from all CTF string - tables in the output link; ctf_link_shuffle_syms() takes a callback which - provides symtab entries in ascending order, and shuffles the function and - data sections to match; and ctf_link_write() emits a CTF file (if there are - no conflicts requiring per-compilation-unit sub-CTF files) or CTF archives - (otherwise) and returns it, suitable for addition in the .ctf section of the - output. */ + ctf_link_add_ctf. Once this is done, a call to ctf_link will merge the type + tables together, generating new CTF files as needed, with this one as a + parent, to contain types from the inputs which conflict. ctf_link_add_strtab + takes a callback which provides string/offset pairs to be added to the + external symbol table and deduplicated from all CTF string tables in the + output link; ctf_link_shuffle_syms takes a callback which provides symtab + entries in ascending order, and shuffles the function and data sections to + match; and ctf_link_write emits a CTF file (if there are no conflicts + requiring per-compilation-unit sub-CTF files) or CTF archives (otherwise) and + returns it, suitable for addition in the .ctf section of the output. */ /* Return the name of the compilation unit this CTF dict or its parent applies to, or a non-null string otherwise: prefer the parent. Used in debugging @@ -151,6 +51,19 @@ ctf_link_input_name (ctf_dict_t *fp) return "(unnamed)"; } +/* Return the cuname of a dict, or the string "unnamed-CU" if none. */ + +static const char * +ctf_unnamed_cuname (ctf_dict_t *fp) +{ + const char *cuname = ctf_cuname (fp); + + if (!cuname) + cuname = "unnamed-CU"; + + return cuname; +} + /* The linker inputs look like this. clin_fp is used for short-circuited CU-mapped links that can entirely avoid the first link phase in some situations in favour of just passing on the contained ctf_dict_t: it is @@ -279,6 +192,7 @@ ctf_link_add_ctf (ctf_dict_t *fp, ctf_archive_t *ctf, const char *name) /* Return a per-CU output CTF dictionary suitable for the given CU, creating and interning it if need be. */ +_libctf_nonnull_((1,2)) static ctf_dict_t * ctf_create_per_cu (ctf_dict_t *fp, const char *cu_name) { @@ -429,21 +343,6 @@ ctf_link_set_memb_name_changer (ctf_dict_t *fp, fp->ctf_link_memb_name_changer_arg = arg; } -typedef struct ctf_link_in_member_cb_arg -{ - /* The shared output dictionary. */ - ctf_dict_t *out_fp; - - /* The cuname of the input file, and an fp to each dictionary in that file - in turn. */ - const char *in_cuname; - ctf_dict_t *in_fp; - - /* If true, this is the CU-mapped portion of a deduplicating link: no child - dictionaries should be created. */ - int cu_mapped; -} ctf_link_in_member_cb_arg_t; - /* Set a function which is used to filter out unwanted variables from the link. */ int ctf_link_set_variable_filter (ctf_dict_t *fp, ctf_link_variable_filter_f *filter, @@ -479,23 +378,22 @@ check_variable (const char *name, ctf_dict_t *fp, ctf_id_t type, return 0; /* Already exists. */ } -/* Link one variable in. */ +/* Link one variable named NAME of type TYPE found in IN_FP into FP. */ static int -ctf_link_one_variable (const char *name, ctf_id_t type, void *arg_) +ctf_link_one_variable (ctf_dict_t *fp, ctf_dict_t *in_fp, const char *name, + ctf_id_t type, int cu_mapped) { - ctf_link_in_member_cb_arg_t *arg = (ctf_link_in_member_cb_arg_t *) arg_; ctf_dict_t *per_cu_out_fp; ctf_id_t dst_type = 0; - ctf_dict_t *insert_fp; ctf_dvdef_t *dvd; /* See if this variable is filtered out. */ - if (arg->out_fp->ctf_link_variable_filter) + if (fp->ctf_link_variable_filter) { - void *farg = arg->out_fp->ctf_link_variable_filter_arg; - if (arg->out_fp->ctf_link_variable_filter (arg->in_fp, name, type, farg)) + void *farg = fp->ctf_link_variable_filter_arg; + if (fp->ctf_link_variable_filter (in_fp, name, type, farg)) return 0; } @@ -503,25 +401,25 @@ ctf_link_one_variable (const char *name, ctf_id_t type, void *arg_) to that first: if it reports a duplicate, or if the type is in a child already, add straight to the child. */ - insert_fp = arg->out_fp; + if ((dst_type = ctf_dedup_type_mapping (fp, in_fp, type)) == CTF_ERR) + return -1; /* errno is set for us. */ - dst_type = ctf_type_mapping (arg->in_fp, type, &insert_fp); if (dst_type != 0) { - if (insert_fp == arg->out_fp) - { - if (check_variable (name, insert_fp, dst_type, &dvd)) - { - /* No variable here: we can add it. */ - if (ctf_add_variable (insert_fp, name, dst_type) < 0) - return (ctf_set_errno (arg->out_fp, ctf_errno (insert_fp))); - return 0; - } + if (!ctf_assert (fp, ctf_type_isparent (fp, dst_type))) + return -1; /* errno is set for us. */ - /* Already present? Nothing to do. */ - if (dvd && dvd->dvd_type == dst_type) - return 0; + if (check_variable (name, fp, dst_type, &dvd)) + { + /* No variable here: we can add it. */ + if (ctf_add_variable (fp, name, dst_type) < 0) + return -1; /* errno is set for us. */ + return 0; } + + /* Already present? Nothing to do. */ + if (dvd && dvd->dvd_type == dst_type) + return 0; } /* Can't add to the parent due to a name clash, or because it references a @@ -529,29 +427,29 @@ ctf_link_one_variable (const char *name, ctf_id_t type, void *arg_) be. If we can't do that, skip it. Don't add to a child if we're doing a CU-mapped link, since that has only one output. */ - if (arg->cu_mapped) + if (cu_mapped) { ctf_dprintf ("Variable %s in input file %s depends on a type %lx hidden " - "due to conflicts: skipped.\n", name, arg->in_cuname, - type); + "due to conflicts: skipped.\n", name, + ctf_unnamed_cuname (in_fp), type); return 0; } - if ((per_cu_out_fp = ctf_create_per_cu (arg->out_fp, arg->in_cuname)) == NULL) - return -1; /* Errno is set for us. */ + if ((per_cu_out_fp = ctf_create_per_cu (fp, ctf_unnamed_cuname (in_fp))) == NULL) + return -1; /* errno is set for us. */ /* If the type was not found, check for it in the child too. */ if (dst_type == 0) { - insert_fp = per_cu_out_fp; - dst_type = ctf_type_mapping (arg->in_fp, type, &insert_fp); + if ((dst_type = ctf_dedup_type_mapping (per_cu_out_fp, + in_fp, type)) == CTF_ERR) + return -1; /* errno is set for us. */ if (dst_type == 0) { - ctf_err_warn (arg->out_fp, 1, 0, - _("type %lx for variable %s in input file %s " - "not found: skipped"), type, name, - arg->in_cuname); + ctf_err_warn (fp, 1, 0, _("type %lx for variable %s in input file %s " + "not found: skipped"), type, name, + ctf_unnamed_cuname (in_fp)); /* Do not terminate the link: just skip the variable. */ return 0; } @@ -559,21 +457,10 @@ ctf_link_one_variable (const char *name, ctf_id_t type, void *arg_) if (check_variable (name, per_cu_out_fp, dst_type, &dvd)) if (ctf_add_variable (per_cu_out_fp, name, dst_type) < 0) - return (ctf_set_errno (arg->out_fp, ctf_errno (per_cu_out_fp))); + return (ctf_set_errno (fp, ctf_errno (per_cu_out_fp))); return 0; } -/* Dump the unnecessary link type mapping after one input file is processed. */ -static void -empty_link_type_mapping (void *key _libctf_unused_, void *value, - void *arg _libctf_unused_) -{ - ctf_dict_t *fp = (ctf_dict_t *) value; - - if (fp->ctf_link_type_mapping) - ctf_dynhash_empty (fp->ctf_link_type_mapping); -} - /* Lazily open a CTF archive for linking, if not already open. Returns the number of files contained within the opened archive (0 for none), @@ -925,21 +812,24 @@ static int ctf_link_deduplicating_variables (ctf_dict_t *fp, ctf_dict_t **inputs, size_t ninputs, int cu_mapped) { - ctf_link_in_member_cb_arg_t arg; size_t i; - arg.cu_mapped = cu_mapped; - arg.out_fp = fp; - for (i = 0; i < ninputs; i++) { - arg.in_fp = inputs[i]; - if (ctf_cuname (inputs[i]) != NULL) - arg.in_cuname = ctf_cuname (inputs[i]); - else - arg.in_cuname = "unnamed-CU"; - if (ctf_variable_iter (arg.in_fp, ctf_link_one_variable, &arg) < 0) - return ctf_set_errno (fp, ctf_errno (arg.in_fp)); + ctf_next_t *it = NULL; + ctf_id_t type; + const char *name; + + while ((type = ctf_variable_next (inputs[i], &it, &name)) != CTF_ERR) + { + if (ctf_link_one_variable (fp, inputs[i], name, type, cu_mapped) < 0) + { + ctf_next_destroy (it); + return -1; /* errno is set for us. */ + } + } + if (ctf_errno (inputs[i]) != ECTF_NEXT_END) + return ctf_set_errno (fp, ctf_errno (inputs[i])); } return 0; } @@ -982,40 +872,35 @@ ctf_link_deduplicating_one_symtypetab (ctf_dict_t *fp, ctf_dict_t *input, ctf_next_t *it = NULL; const char *name; ctf_id_t type; - const char *in_file_name; - - if (ctf_cuname (input) != NULL) - in_file_name = ctf_cuname (input); - else - in_file_name = "unnamed-CU"; while ((type = ctf_symbol_next (input, &it, &name, functions)) != CTF_ERR) { ctf_id_t dst_type; ctf_dict_t *per_cu_out_fp; - ctf_dict_t *insert_fp = fp; int sym; /* Look in the parent first. */ - dst_type = ctf_type_mapping (input, type, &insert_fp); + if ((dst_type = ctf_dedup_type_mapping (fp, input, type)) == CTF_ERR) + return -1; /* errno is set for us. */ + if (dst_type != 0) { - if (insert_fp == fp) - { - sym = check_sym (fp, name, dst_type, functions); + if (!ctf_assert (fp, ctf_type_isparent (fp, dst_type))) + return -1; /* errno is set for us. */ - /* Already present: next symbol. */ - if (sym == 0) - continue; - /* Not present: add it. */ - else if (sym > 0) - { - if (ctf_add_funcobjt_sym (fp, functions, - name, dst_type) < 0) - return -1; /* errno is set for us. */ - continue; - } + sym = check_sym (fp, name, dst_type, functions); + + /* Already present: next symbol. */ + if (sym == 0) + continue; + /* Not present: add it. */ + else if (sym > 0) + { + if (ctf_add_funcobjt_sym (fp, functions, + name, dst_type) < 0) + return -1; /* errno is set for us. */ + continue; } } @@ -1028,24 +913,26 @@ ctf_link_deduplicating_one_symtypetab (ctf_dict_t *fp, ctf_dict_t *input, { ctf_dprintf ("Symbol %s in input file %s depends on a type %lx " "hidden due to conflicts: skipped.\n", name, - in_file_name, type); + ctf_unnamed_cuname (input), type); continue; } - if ((per_cu_out_fp = ctf_create_per_cu (fp, in_file_name)) == NULL) + if ((per_cu_out_fp = ctf_create_per_cu (fp, ctf_unnamed_cuname (input))) == NULL) return -1; /* errno is set for us. */ /* If the type was not found, check for it in the child too. */ if (dst_type == 0) { - insert_fp = per_cu_out_fp; - dst_type = ctf_type_mapping (input, type, &insert_fp); + if ((dst_type = ctf_dedup_type_mapping (per_cu_out_fp, + input, type)) == CTF_ERR) + return -1; /* errno is set for us. */ if (dst_type == 0) { ctf_err_warn (fp, 1, 0, _("type %lx for symbol %s in input file %s " - "not found: skipped"), type, name, in_file_name); + "not found: skipped"), type, name, + ctf_unnamed_cuname (input)); continue; } } @@ -1068,7 +955,7 @@ ctf_link_deduplicating_one_symtypetab (ctf_dict_t *fp, ctf_dict_t *input, ctf_err_warn (fp, 0, ECTF_DUPLICATE, _("symbol %s in input file %s found conflicting " "even when trying in per-CU dict."), name, - in_file_name); + ctf_unnamed_cuname (input)); return (ctf_set_errno (fp, ECTF_DUPLICATE)); } } @@ -1258,6 +1145,8 @@ ctf_link_deduplicating_per_cu (ctf_dict_t *fp) goto err_inputs_outputs; } + ctf_dedup_fini (out, outputs, noutputs); + /* For now, we omit symbol section linking for CU-mapped links, until it is clear how to unify the symbol table across such links. (Perhaps we should emit an unconditionally indexed symtab, like the compiler @@ -1420,6 +1309,8 @@ ctf_link_deduplicating (ctf_dict_t *fp) goto err_clean_outputs; } + ctf_dedup_fini (fp, outputs, noutputs); + /* Now close all the inputs, including per-CU intermediates. */ if (ctf_link_deduplicating_close_inputs (fp, NULL, inputs, ninputs) < 0) @@ -1452,12 +1343,9 @@ ctf_link_deduplicating (ctf_dict_t *fp) int ctf_link (ctf_dict_t *fp, int flags) { - ctf_link_in_member_cb_arg_t arg; ctf_next_t *i = NULL; int err; - memset (&arg, 0, sizeof (struct ctf_link_in_member_cb_arg)); - arg.out_fp = fp; fp->ctf_link_flags = flags; if (fp->ctf_link_inputs == NULL) @@ -1503,11 +1391,6 @@ ctf_link (ctf_dict_t *fp, int flags) ctf_link_deduplicating (fp); - /* Discard the now-unnecessary mapping table data from all the outputs. */ - if (fp->ctf_link_type_mapping) - ctf_dynhash_empty (fp->ctf_link_type_mapping); - ctf_dynhash_iter (fp->ctf_link_outputs, empty_link_type_mapping, NULL); - fp->ctf_flags &= ~LCTF_LINKING; if ((ctf_errno (fp) != 0) && (ctf_errno (fp) != ECTF_NOCTFDATA)) return -1; @@ -1537,8 +1420,8 @@ ctf_link_intern_extern_string (void *key _libctf_unused_, void *value, /* Repeatedly call ADD_STRING to acquire strings from the external string table, adding them to the atoms table for this CU and all subsidiary CUs. - If ctf_link() is also called, it must be called first if you want the new CTF - files ctf_link() can create to get their strings dedupped against the ELF + If ctf_link is also called, it must be called first if you want the new CTF + files ctf_link can create to get their strings dedupped against the ELF strtab properly. */ int ctf_link_add_strtab (ctf_dict_t *fp, ctf_link_strtab_string_f *add_string, |