From f445b98611f4ae67e645d0a2b75dd5cfa76bf23a Mon Sep 17 00:00:00 2001 From: Christian Biesinger Date: Mon, 30 Sep 2019 16:47:37 -0500 Subject: [PATCH] Compute msymbol hash codes in parallel This is for the msymbol_hash and msymbol_demangled_hash hashtables in objfile_per_bfd_storage. This basically computes those hash codes together with the demangled symbol name in the background, before it inserts the symbols in the hash table. gdb/ChangeLog: 2019-09-30 Christian Biesinger * minsyms.c (add_minsym_to_hash_table): Use a previously computed hash code if possible. (add_minsym_to_demangled_hash_table): Likewise. (minimal_symbol_reader::install): Compute the hash codes for msymbol on the background thread. * symtab.h (struct minimal_symbol) : Add these fields. Change-Id: Ifaa3346e9998f05743bff9e2eaad3f83b954d071 --- gdb/minsyms.c | 40 +++++++++++++++++++++++++--------------- 1 file changed, 25 insertions(+), 15 deletions(-) diff --git a/gdb/minsyms.c b/gdb/minsyms.c index d2d8bf50596..be529235c80 100644 --- a/gdb/minsyms.c +++ b/gdb/minsyms.c @@ -141,12 +141,12 @@ msymbol_hash (const char *string) /* Add the minimal symbol SYM to an objfile's minsym hash table, TABLE. */ static void add_minsym_to_hash_table (struct minimal_symbol *sym, - struct minimal_symbol **table) + struct minimal_symbol **table, + unsigned int hash_value) { if (sym->hash_next == NULL) { - unsigned int hash - = msymbol_hash (MSYMBOL_LINKAGE_NAME (sym)) % MINIMAL_SYMBOL_HASH_SIZE; + unsigned int hash = hash_value % MINIMAL_SYMBOL_HASH_SIZE; sym->hash_next = table[hash]; table[hash] = sym; @@ -157,18 +157,16 @@ add_minsym_to_hash_table (struct minimal_symbol *sym, TABLE. */ static void add_minsym_to_demangled_hash_table (struct minimal_symbol *sym, - struct objfile *objfile) + struct objfile *objfile, + unsigned int hash_value) { if (sym->demangled_hash_next == NULL) { - unsigned int hash = search_name_hash (MSYMBOL_LANGUAGE (sym), - MSYMBOL_SEARCH_NAME (sym)); - objfile->per_bfd->demangled_hash_languages.set (MSYMBOL_LANGUAGE (sym)); struct minimal_symbol **table = objfile->per_bfd->msymbol_demangled_hash; - unsigned int hash_index = hash % MINIMAL_SYMBOL_HASH_SIZE; + unsigned int hash_index = hash_value % MINIMAL_SYMBOL_HASH_SIZE; sym->demangled_hash_next = table[hash_index]; table[hash_index] = sym; } @@ -1262,6 +1260,8 @@ struct computed_hash_values { size_t name_length; hashval_t mangled_name_hash; + unsigned int minsym_hash; + unsigned int minsym_demangled_hash; }; /* Build (or rebuild) the minimal symbol hash tables. This is necessary @@ -1269,23 +1269,28 @@ struct computed_hash_values thus causing the internal minimal_symbol pointers to become jumbled. */ static void -build_minimal_symbol_hash_tables (struct objfile *objfile) +build_minimal_symbol_hash_tables + (struct objfile *objfile, + const std::vector& hash_values) { int i; struct minimal_symbol *msym; /* (Re)insert the actual entries. */ - for ((i = objfile->per_bfd->minimal_symbol_count, + int mcount = objfile->per_bfd->minimal_symbol_count; + for ((i = 0, msym = objfile->per_bfd->msymbols.get ()); - i > 0; - i--, msym++) + i < mcount; + i++, msym++) { msym->hash_next = 0; - add_minsym_to_hash_table (msym, objfile->per_bfd->msymbol_hash); + add_minsym_to_hash_table (msym, objfile->per_bfd->msymbol_hash, + hash_values[i].minsym_hash); msym->demangled_hash_next = 0; if (MSYMBOL_SEARCH_NAME (msym) != MSYMBOL_LINKAGE_NAME (msym)) - add_minsym_to_demangled_hash_table (msym, objfile); + add_minsym_to_demangled_hash_table + (msym, objfile, hash_values[i].minsym_demangled_hash); } } @@ -1400,6 +1405,11 @@ minimal_symbol_reader::install () hash_values[idx].mangled_name_hash = fast_hash (msym->name, hash_values[idx].name_length); } + hash_values[idx].minsym_hash + = msymbol_hash (MSYMBOL_LINKAGE_NAME (msym)); + hash_values[idx].minsym_demangled_hash + = search_name_hash (MSYMBOL_LANGUAGE (msym), + MSYMBOL_SEARCH_NAME (msym)); } { /* To limit how long we hold the lock, we only acquire it here @@ -1421,7 +1431,7 @@ minimal_symbol_reader::install () } }); - build_minimal_symbol_hash_tables (m_objfile); + build_minimal_symbol_hash_tables (m_objfile, hash_values); } } -- 2.47.2