From c30081c1f955a9fea2da8988bab96191e3d2171e Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Thu, 7 Jul 2022 08:40:26 +0930 Subject: [PATCH] gas: utility notes memory alloc functions Makes it a little easier to use the notes obstack for persistent storage. * as.h (gas_mul_overflow): Define. * symbols.h (notes_alloc, notes_calloc, notes_memdup), (notes_strdup, notes_concat, notes_free): Declare. * symbols.c (notes_alloc, notes_calloc, notes_memdup), (notes_strdup, notes_concat, notes_free): New functions. (save_symbol_name): Use notes_strdup. (symbol_create, local_symbol_make, local_symbol_convert), (symbol_clone, decode_local_label_name): Use notes_alloc. --- gas/as.h | 8 +++++ gas/symbols.c | 85 +++++++++++++++++++++++++++++++++++++++++++++------ gas/symbols.h | 7 +++++ 3 files changed, 90 insertions(+), 10 deletions(-) diff --git a/gas/as.h b/gas/as.h index 4fac7d21a32..0ee3873bd1a 100644 --- a/gas/as.h +++ b/gas/as.h @@ -122,6 +122,14 @@ void *mempcpy(void *, const void *, size_t); #define xfree free +#if GCC_VERSION >= 7000 +#define gas_mul_overflow(a, b, res) __builtin_mul_overflow (a, b, res) +#else +/* Assumes unsigned values. Careful! Args evaluated multiple times. */ +#define gas_mul_overflow(a, b, res) \ + ((*res) = (a), (*res) *= (b), (b) != 0 && (*res) / (b) != (a)) +#endif + #include "asintl.h" #define BAD_CASE(val) \ diff --git a/gas/symbols.c b/gas/symbols.c index e3fddee8c79..00ae49b91ed 100644 --- a/gas/symbols.c +++ b/gas/symbols.c @@ -242,6 +242,75 @@ struct xsymbol dot_symbol_x; #endif struct obstack notes; + +/* Utility functions to allocate and duplicate memory on the notes + obstack, each like the corresponding function without "notes_" + prefix. All of these exit on an allocation failure. */ + +void * +notes_alloc (size_t size) +{ + return obstack_alloc (¬es, size); +} + +void * +notes_calloc (size_t n, size_t size) +{ + size_t amt; + void *ret; + if (gas_mul_overflow (n, size, &amt)) + { + obstack_alloc_failed_handler (); + abort (); + } + ret = notes_alloc (amt); + memset (ret, 0, amt); + return ret; +} + +void * +notes_memdup (const void *src, size_t copy_size, size_t alloc_size) +{ + void *ret = obstack_alloc (¬es, alloc_size); + memcpy (ret, src, copy_size); + if (alloc_size > copy_size) + memset ((char *) ret + copy_size, 0, alloc_size - copy_size); + return ret; +} + +char * +notes_strdup (const char *str) +{ + size_t len = strlen (str) + 1; + return notes_memdup (str, len, len); +} + +char * +notes_concat (const char *first, ...) +{ + va_list args; + const char *str; + + va_start (args, first); + for (str = first; str; str = va_arg (args, const char *)) + { + size_t size = strlen (str); + obstack_grow (¬es, str, size); + } + va_end (args); + obstack_1grow (¬es, 0); + return obstack_finish (¬es); +} + +/* Use with caution! Frees PTR and all more recently allocated memory + on the notes obstack. */ + +void +notes_free (void *ptr) +{ + obstack_free (¬es, ptr); +} + #ifdef TE_PE /* The name of an external symbol which is used to make weak PE symbol names unique. */ @@ -274,13 +343,10 @@ symbol_new (const char *name, segT segment, fragS *frag, valueT valu) static const char * save_symbol_name (const char *name) { - size_t name_length; char *ret; gas_assert (name != NULL); - name_length = strlen (name) + 1; /* +1 for \0. */ - obstack_grow (¬es, name, name_length); - ret = (char *) obstack_finish (¬es); + ret = notes_strdup (name); #ifdef tc_canonicalize_symbol_name ret = tc_canonicalize_symbol_name (ret); @@ -343,7 +409,7 @@ symbol_create (const char *name, segT segment, fragS *frag, valueT valu) preserved_copy_of_name = save_symbol_name (name); size = sizeof (symbolS) + sizeof (struct xsymbol); - symbolP = (symbolS *) obstack_alloc (¬es, size); + symbolP = notes_alloc (size); /* symbol must be born in some fixed state. This seems as good as any. */ memset (symbolP, 0, size); @@ -377,7 +443,7 @@ local_symbol_make (const char *name, segT section, fragS *frag, valueT val) name_copy = save_symbol_name (name); - ret = (struct local_symbol *) obstack_alloc (¬es, sizeof *ret); + ret = notes_alloc (sizeof *ret); ret->flags = flags; ret->hash = 0; ret->name = name_copy; @@ -403,7 +469,7 @@ local_symbol_convert (void *sym) ++local_symbol_conversion_count; - xtra = (struct xsymbol *) obstack_alloc (¬es, sizeof (*xtra)); + xtra = notes_alloc (sizeof (*xtra)); memset (xtra, 0, sizeof (*xtra)); val = ent->lsy.value; ent->sy.x = xtra; @@ -717,8 +783,7 @@ symbol_clone (symbolS *orgsymP, int replace) orgsymP = local_symbol_convert (orgsymP); bsymorg = orgsymP->bsym; - newsymP = (symbolS *) obstack_alloc (¬es, (sizeof (symbolS) - + sizeof (struct xsymbol))); + newsymP = notes_alloc (sizeof (symbolS) + sizeof (struct xsymbol)); *newsymP = *orgsymP; newsymP->x = (struct xsymbol *) (newsymP + 1); *newsymP->x = *orgsymP->x; @@ -2104,7 +2169,7 @@ decode_local_label_name (char *s) instance_number = (10 * instance_number) + *p - '0'; message_format = _("\"%d\" (instance number %d of a %s label)"); - symbol_decode = (char *) obstack_alloc (¬es, strlen (message_format) + 30); + symbol_decode = notes_alloc (strlen (message_format) + 30); sprintf (symbol_decode, message_format, label_number, instance_number, type); return symbol_decode; diff --git a/gas/symbols.h b/gas/symbols.h index 19eb658ca68..240e08f8df6 100644 --- a/gas/symbols.h +++ b/gas/symbols.h @@ -35,6 +35,13 @@ extern int symbol_table_frozen; default. */ extern int symbols_case_sensitive; +extern void *notes_alloc (size_t); +extern void *notes_calloc (size_t, size_t); +extern void *notes_memdup (const void *, size_t, size_t); +extern char *notes_strdup (const char *); +extern char *notes_concat (const char *, ...); +extern void notes_free (void *); + char * symbol_relc_make_expr (expressionS *); char * symbol_relc_make_sym (symbolS *); char * symbol_relc_make_value (offsetT); -- 2.30.2