From 741d7538b7540fea1086fe6ab962227d2cf7418e Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Sat, 2 Mar 2019 12:05:57 -0700 Subject: [PATCH] Remove minsym termination I was curious what used the terminating "null" minimal symbol; and after looking I could not find anything. This patch removes terminate_minimal_symbol_table and the extra minimal symbol that is allocated for it. gdb/ChangeLog 2019-03-15 Tom Tromey * symfile.c (reread_symbols): Update. * objfiles.c (objfile::objfile): Update. * minsyms.h (terminate_minimal_symbol_table): Don't declare. * minsyms.c (lookup_minimal_symbol_by_pc_section): Update comment. (minimal_symbol_reader::install): Update. (terminate_minimal_symbol_table): Remove. * jit.c (jit_object_close_impl): Update. --- gdb/ChangeLog | 11 +++++++++++ gdb/jit.c | 2 -- gdb/minsyms.c | 40 +++------------------------------------- gdb/minsyms.h | 7 ------- gdb/objfiles.c | 2 -- gdb/symfile.c | 1 - 6 files changed, 14 insertions(+), 49 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index ceedf536e5..e1adb08b3a 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,14 @@ +2019-03-15 Tom Tromey + + * symfile.c (reread_symbols): Update. + * objfiles.c (objfile::objfile): Update. + * minsyms.h (terminate_minimal_symbol_table): Don't declare. + * minsyms.c (lookup_minimal_symbol_by_pc_section): Update + comment. + (minimal_symbol_reader::install): Update. + (terminate_minimal_symbol_table): Remove. + * jit.c (jit_object_close_impl): Update. + 2019-03-15 Tom Tromey * minsyms.c (minimal_symbol_reader::record_full): Remove some diff --git a/gdb/jit.c b/gdb/jit.c index 81c4af40f9..1f87bf2538 100644 --- a/gdb/jit.c +++ b/gdb/jit.c @@ -805,8 +805,6 @@ jit_object_close_impl (struct gdb_symbol_callbacks *cb, OBJF_NOT_FILENAME); objfile->per_bfd->gdbarch = target_gdbarch (); - terminate_minimal_symbol_table (objfile); - j = NULL; for (i = obj->symtabs; i; i = j) { diff --git a/gdb/minsyms.c b/gdb/minsyms.c index bc6e536de8..efeaf2a019 100644 --- a/gdb/minsyms.c +++ b/gdb/minsyms.c @@ -735,11 +735,8 @@ lookup_minimal_symbol_by_pc_section (CORE_ADDR pc_in, struct obj_section *sectio { CORE_ADDR pc = pc_in; - /* If this objfile has a minimal symbol table, go search it using - a binary search. Note that a minimal symbol table always consists - of at least two symbols, a "real" symbol and the terminating - "null symbol". If there are no real symbols, then there is no - minimal symbol table at all. */ + /* If this objfile has a minimal symbol table, go search it + using a binary search. */ if (objfile->per_bfd->minimal_symbol_count > 0) { @@ -1363,7 +1360,7 @@ minimal_symbol_reader::install () compact out the duplicate entries. Once we have a final table, we will give back the excess space. */ - alloc_count = m_msym_count + m_objfile->per_bfd->minimal_symbol_count + 1; + alloc_count = m_msym_count + m_objfile->per_bfd->minimal_symbol_count; obstack_blank (&m_objfile->per_bfd->storage_obstack, alloc_count * sizeof (struct minimal_symbol)); msymbols = (struct minimal_symbol *) @@ -1406,16 +1403,6 @@ minimal_symbol_reader::install () msymbols = (struct minimal_symbol *) obstack_finish (&m_objfile->per_bfd->storage_obstack); - /* We also terminate the minimal symbol table with a "null symbol", - which is *not* included in the size of the table. This makes it - easier to find the end of the table when we are handed a pointer - to some symbol in the middle of it. Zero out the fields in the - "null symbol" allocated at the end of the array. Note that the - symbol count does *not* include this null symbol, which is why it - is indexed by mcount and not mcount-1. */ - - memset (&msymbols[mcount], 0, sizeof (struct minimal_symbol)); - /* Attach the minimal symbol table to the specified objfile. The strings themselves are also located in the storage_obstack of this objfile. */ @@ -1431,27 +1418,6 @@ minimal_symbol_reader::install () } } -/* See minsyms.h. */ - -void -terminate_minimal_symbol_table (struct objfile *objfile) -{ - if (! objfile->per_bfd->msymbols) - objfile->per_bfd->msymbols = XOBNEW (&objfile->per_bfd->storage_obstack, - minimal_symbol); - - { - struct minimal_symbol *m - = &objfile->per_bfd->msymbols[objfile->per_bfd->minimal_symbol_count]; - - memset (m, 0, sizeof (*m)); - /* Don't rely on these enumeration values being 0's. */ - MSYMBOL_TYPE (m) = mst_unknown; - MSYMBOL_SET_LANGUAGE (m, language_unknown, - &objfile->per_bfd->storage_obstack); - } -} - /* Check if PC is in a shared library trampoline code stub. Return minimal symbol for the trampoline entry or NULL if PC is not in a trampoline code stub. */ diff --git a/gdb/minsyms.h b/gdb/minsyms.h index 532436c16c..3e414f6ff7 100644 --- a/gdb/minsyms.h +++ b/gdb/minsyms.h @@ -148,13 +148,6 @@ class minimal_symbol_reader int m_msym_count; }; -/* Create the terminating entry of OBJFILE's minimal symbol table. - If OBJFILE->msymbols is zero, allocate a single entry from - OBJFILE->objfile_obstack; otherwise, just initialize - OBJFILE->msymbols[OBJFILE->minimal_symbol_count]. */ - -void terminate_minimal_symbol_table (struct objfile *objfile); - /* Return whether MSYMBOL is a function/method. If FUNC_ADDRESS_P is diff --git a/gdb/objfiles.c b/gdb/objfiles.c index 4091b42dbf..2468ca7a3f 100644 --- a/gdb/objfiles.c +++ b/gdb/objfiles.c @@ -411,8 +411,6 @@ objfile::objfile (bfd *abfd, const char *name, objfile_flags flags_) per_bfd = get_objfile_bfd_data (this, abfd); - terminate_minimal_symbol_table (this); - /* Add this file onto the tail of the linked list of other such files. */ if (object_files == NULL) diff --git a/gdb/symfile.c b/gdb/symfile.c index 2214f16b43..68ec491d35 100644 --- a/gdb/symfile.c +++ b/gdb/symfile.c @@ -2580,7 +2580,6 @@ reread_symbols (void) objfile_set_sym_fns (objfile, find_sym_fns (objfile->obfd)); build_objfile_section_table (objfile); - terminate_minimal_symbol_table (objfile); /* We use the same section offsets as from last time. I'm not sure whether that is always correct for shared libraries. */ -- 2.34.1