| Message ID | oregc8w2by.fsf@livre.home |
|---|---|
| State | New |
| Headers | show |
On Sat, Feb 20, 2016 at 3:19 AM, Alexandre Oliva <aoliva@redhat.com> wrote: > Keith Seitz reported we were missing debug information for cdtors. > E.g., we emit a specification for the unified ctor and dtor, but then, > if we emit one of the in-charge and not-in-charge versions as an alias > to the other, from the debug info PoV it's as if one of them didn't > exist. If we emit declone them, emitting the unified cdtor and the > others are trampolines to it, it's as if we had an extra cdtor, because > there's no info that the others are just trampolines. > > This patch implements some improvements in this regard: > > - when we emit a symbol as an alias (or weakref) to another, we now emit > a DW_TAG_imported_decl definition for it, naming the alias target's > DIE in a DW_AT_import attribute. > > - when we emit decloned cdtor trampolines, or other kinds of thunks, we > now annotate their DIEs with DW_AT_trampoline, referencing the > target's DIE. > > I realize this is a bit late for GCC 6, but I figured I'd post it right > now, so that I can work on any required changes while it's still fresh > in my mind. Now, if someone agrees it is safe enough even for 6, I > surely wouldn't mind that either ;-) > > This was regstrapped on x86_64-linux-gnu and i686-linux-gnu, and I > checked for any regressions in the GDB test results too, for good > measure (there were none) > > Ok to install, now or later? I think this breaks early-debug assumptions in creating new decl DIEs rather than just annotating old ones. So assemble_aliases is the wrong spot to do this. Richard. > > support aliases and trampolines in dwarf2 > > for gcc/ChangeLog > > * debug.h (struct gcc_debug_hooks): Add aliased_decl and > trampoline_decl. > * dwarf2out.c (dwarf2out_aliased_decl): New. > (dwarf2out_trampoline_decl): New. > (dwarf2_debug_hooks): Add them. > (dwarf2_name): Skip leading '*' returned by langhook. > (dwarf2_lineno_debug_hooks): Add dummies. > * debug.c (do_nothing_debug_hooks): Likewise. > * dbxout.c (dbx_debug_hooks, xcoff_debug_hooks): Likewise. > * sdbout.c (sdb_debug_hooks): Likewise. > * vmsdbgout.c (vmsdbg_debug_hooks): Likewise. > * cgraph.h (cgraph_node::is_lang_trampoline): Declare. > * cgraphunit.c: Include demangle.h. > (cgraph_node::expand_thunk): Call function_decl debug_hook > after assembly expansion. Do not mark thunk as ignored in > gimple expansion. > (cxx_cdtor_trampoline_p): New. > (cgraph_node::is_lang_trampoline): New. > (cgraph_node::assemble_thunks_and_aliases): Call the new > debug_hooks. > (symbol_table::output_weakrefs): Likewise. > * varpool.c (varpool_node::assemble_aliases): Likewise. > > for gcc/cp/ChangeLog > > * method.c (make_alias_for): Copy DECL_IGNORED_P. > > for gcc/testsuite/ChangeLog > > * g++.dg/debug/dwarf2/cdtor-1.C: Adjust linkage_name count. > * g++.dg/debug/dwarf2/cdtor-2.C: New. > * g++.dg/debug/dwarf2/cdtor-3.C: New. > * g++.dg/debug/dwarf2/covariant-1.C: New. > * gcc.dg/debug/dwarf2/attr-alias-1.c: New. > * gcc.dg/debug/dwarf2/attr-alias-2.c: New. > * gcc.dg/debug/dwarf2/attr-weakref-1.c: New. > * gcc.dg/debug/dwarf2/attr-weakref-2.c: New. > --- > gcc/cgraph.h | 4 + > gcc/cgraphunit.c | 134 +++++++++++++++++++- > gcc/cp/method.c | 1 > gcc/dbxout.c | 4 + > gcc/debug.c | 2 > gcc/debug.h | 8 + > gcc/dwarf2out.c | 100 +++++++++++++++ > gcc/sdbout.c | 2 > gcc/testsuite/g++.dg/debug/dwarf2/cdtor-1.C | 2 > gcc/testsuite/g++.dg/debug/dwarf2/cdtor-2.C | 13 ++ > gcc/testsuite/g++.dg/debug/dwarf2/cdtor-3.C | 17 +++ > gcc/testsuite/g++.dg/debug/dwarf2/covariant-1.C | 24 ++++ > gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-1.c | 10 + > gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-2.c | 10 + > gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-1.c | 10 + > gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-2.c | 10 + > gcc/varpool.c | 8 + > gcc/vmsdbgout.c | 2 > 18 files changed, 349 insertions(+), 12 deletions(-) > create mode 100644 gcc/testsuite/g++.dg/debug/dwarf2/cdtor-2.C > create mode 100644 gcc/testsuite/g++.dg/debug/dwarf2/cdtor-3.C > create mode 100644 gcc/testsuite/g++.dg/debug/dwarf2/covariant-1.C > create mode 100644 gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-1.c > create mode 100644 gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-2.c > create mode 100644 gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-1.c > create mode 100644 gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-2.c > > diff --git a/gcc/cgraph.h b/gcc/cgraph.h > index fc7bb22..4d8bf05 100644 > --- a/gcc/cgraph.h > +++ b/gcc/cgraph.h > @@ -1117,6 +1117,10 @@ public: > external means. */ > inline void mark_force_output (void); > > + /* Return true when function is a language-defined trampoline, e.g., > + C++ ctor and dtor "thunks" that just call the unified cdtor. */ > + bool is_lang_trampoline (void); > + > /* Return true when function can be marked local. */ > bool local_p (void); > > diff --git a/gcc/cgraphunit.c b/gcc/cgraphunit.c > index 0a745f0..b399d61 100644 > --- a/gcc/cgraphunit.c > +++ b/gcc/cgraphunit.c > @@ -203,6 +203,7 @@ along with GCC; see the file COPYING3. If not see > #include "dbgcnt.h" > #include "tree-chkp.h" > #include "lto-section-names.h" > +#include "demangle.h" > > /* Queue of cgraph nodes scheduled to be added into cgraph. This is a > secondary queue used during optimization to accommodate passes that > @@ -1635,6 +1636,12 @@ cgraph_node::expand_thunk (bool output_asm_thunks, bool force_gimple_thunk) > assemble_end_function (thunk_fndecl, fnname); > insn_locations_finalize (); > init_insn_lengths (); > + > + timevar_push (TV_SYMOUT); > + if (!DECL_IGNORED_P (thunk_fndecl)) > + (*debug_hooks->function_decl) (thunk_fndecl); > + timevar_pop (TV_SYMOUT); > + > free_after_compilation (cfun); > TREE_ASM_WRITTEN (thunk_fndecl) = 1; > thunk.thunk_p = false; > @@ -1676,7 +1683,6 @@ cgraph_node::expand_thunk (bool output_asm_thunks, bool force_gimple_thunk) > resolve_unique_section (thunk_fndecl, 0, > flag_function_sections); > > - DECL_IGNORED_P (thunk_fndecl) = 1; > bitmap_obstack_initialize (NULL); > > if (thunk.virtual_offset_p) > @@ -1889,6 +1895,92 @@ cgraph_node::expand_thunk (bool output_asm_thunks, bool force_gimple_thunk) > return true; > } > > +/* Return true if DECL is a cdtor trampoline for unified cdtor > + TARGET. */ > + > +static bool > +cxx_cdtor_trampoline_p (tree decl, tree target) > +{ > + if (DECL_ABSTRACT_ORIGIN (decl)) > + return false; > + > + if (!DECL_CXX_CONSTRUCTOR_P (decl) && !DECL_CXX_DESTRUCTOR_P (decl)) > + return false; > + > + if (DECL_CXX_CONSTRUCTOR_P (decl) != DECL_CXX_CONSTRUCTOR_P (target)) > + return false; > + > + if (DECL_CXX_DESTRUCTOR_P (decl) != DECL_CXX_DESTRUCTOR_P (target)) > + return false; > + > + gcc_assert (DECL_ASSEMBLER_NAME_SET_P (decl)); > + gcc_assert (DECL_ASSEMBLER_NAME_SET_P (target)); > + > + const char *dname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); > + const char *tname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (target)); > + > + unsigned int i = strlen (dname); > + if (i != strlen (tname)) > + return false; > + > + gcc_assert (i); > + > + /* C1 and C2 ctors may be trampolines to C4; D0, D1 and D2 dtors may > + be trampolines to D4. Check their mangled names, so that the > + test will work even during LTO compilations, when the cdtor > + clones retrofitted into trampolines might not be right after the > + unified one in the DECL_CHAIN, and we don't have C++-specific > + data structures or lang hooks to check that the cdtors are of > + different kinds and belong to the same class. > + > + Alas, just checking that the assembler name has e.g. C2 vs C4 as > + the only difference could find false positives, e.g., if there > + are cdtors with the same signature (aside from the THIS pointer) > + in classes whose names contain C2 and C4, say _ZN2C2C1Ev AKA > + C2::C2() and _ZN2C4C1Ev AKA C4::C4(). > + > + So, after checking that we found viable distinguishing characters > + at the expected place, we check that the cdtors are of different > + kinds using the demangler. Yuck. */ > + bool found = false; > + while (i--) > + if (dname[i] != tname[i]) > + { > + if (!found > + && tname[i] == '4' && i && tname[i-1] == dname[i-1] > + && (((dname[i-1] == 'C' || dname[i-1] == 'D') > + && (dname[i] == '1' || dname[i] == '2')) > + || (dname[i-1] == 'D' && dname[i] == '0'))) > + found = true; > + else > + return false; > + } > + > + if (DECL_CXX_CONSTRUCTOR_P (decl)) > + return is_gnu_v3_mangled_ctor (tname) == gnu_v3_unified_ctor > + && is_gnu_v3_mangled_ctor (dname) != gnu_v3_unified_ctor; > + else if (DECL_CXX_DESTRUCTOR_P (decl)) > + return is_gnu_v3_mangled_dtor (tname) == gnu_v3_unified_dtor > + && is_gnu_v3_mangled_dtor (dname) != gnu_v3_unified_dtor; > + else > + gcc_unreachable (); > +} > + > +/* Return true when function is as a language-defined trampoline, > + e.g., C++ ctor and dtor "thunks" that just call the unified > + cdtor. */ > + > +bool > +cgraph_node::is_lang_trampoline (void) > +{ > + if (!callees || callees->next_callee) > + return false; > + > + tree target = callees->callee->decl; > + > + return (cxx_cdtor_trampoline_p (decl, target)); > +} > + > /* Assemble thunks and aliases associated to node. */ > > void > @@ -1906,9 +1998,17 @@ cgraph_node::assemble_thunks_and_aliases (void) > e = e->next_caller; > thunk->expand_thunk (true, false); > thunk->assemble_thunks_and_aliases (); > + if (!DECL_IGNORED_P (thunk->decl) && !DECL_IGNORED_P (decl)) > + (*debug_hooks->trampoline_decl) (thunk->decl, decl); > } > else > - e = e->next_caller; > + { > + if (e->caller->is_lang_trampoline () > + && !DECL_IGNORED_P (e->caller->decl) && !DECL_IGNORED_P (decl)) > + (*debug_hooks->trampoline_decl) (e->caller->decl, decl); > + > + e = e->next_caller; > + } > > FOR_EACH_ALIAS (this, ref) > { > @@ -1922,6 +2022,8 @@ cgraph_node::assemble_thunks_and_aliases (void) > TREE_ASM_WRITTEN (decl) = 1; > do_assemble_alias (alias->decl, > DECL_ASSEMBLER_NAME (decl)); > + if (!DECL_IGNORED_P (alias->decl) && !DECL_IGNORED_P (decl)) > + (*debug_hooks->aliased_decl) (alias->decl, decl); > alias->assemble_thunks_and_aliases (); > TREE_ASM_WRITTEN (decl) = saved_written; > } > @@ -2341,7 +2443,7 @@ symbol_table::output_weakrefs (void) > || !TREE_ASM_WRITTEN (cnode->instrumented_version->decl)) > && node->weakref) > { > - tree target; > + tree target, target_decl; > > /* Weakrefs are special by not requiring target definition in current > compilation unit. It is thus bit hard to work out what we want to > @@ -2349,17 +2451,33 @@ symbol_table::output_weakrefs (void) > When alias target is defined, we need to fetch it from symtab reference, > otherwise it is pointed to by alias_target. */ > if (node->alias_target) > - target = (DECL_P (node->alias_target) > - ? DECL_ASSEMBLER_NAME (node->alias_target) > - : node->alias_target); > + { > + if (DECL_P (node->alias_target)) > + { > + target_decl = node->alias_target; > + target = DECL_ASSEMBLER_NAME (target_decl); > + } > + else > + { > + target_decl = NULL_TREE; > + target = node->alias_target; > + } > + } > else if (node->analyzed) > - target = DECL_ASSEMBLER_NAME (node->get_alias_target ()->decl); > + { > + target_decl = node->get_alias_target ()->decl; > + target = DECL_ASSEMBLER_NAME (target_decl); > + } > else > { > gcc_unreachable (); > - target = get_alias_symbol (node->decl); > + target_decl = node->decl; > + target = get_alias_symbol (target_decl); > } > do_assemble_alias (node->decl, target); > + if (target_decl && !DECL_IGNORED_P (node->decl) > + && !DECL_IGNORED_P (target_decl)) > + (*debug_hooks->aliased_decl) (node->decl, target_decl); > } > } > > diff --git a/gcc/cp/method.c b/gcc/cp/method.c > index e358ebd..24872d1 100644 > --- a/gcc/cp/method.c > +++ b/gcc/cp/method.c > @@ -219,6 +219,7 @@ make_alias_for (tree target, tree newid) > } > DECL_EXTERNAL (alias) = 0; > DECL_ARTIFICIAL (alias) = 1; > + DECL_IGNORED_P (alias) = DECL_IGNORED_P (target); > DECL_TEMPLATE_INSTANTIATED (alias) = 0; > if (TREE_CODE (alias) == FUNCTION_DECL) > { > diff --git a/gcc/dbxout.c b/gcc/dbxout.c > index 25a03ef..8da8eb0 100644 > --- a/gcc/dbxout.c > +++ b/gcc/dbxout.c > @@ -372,6 +372,8 @@ const struct gcc_debug_hooks dbx_debug_hooks = > debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ > debug_nothing_tree, /* deferred_inline_function */ > debug_nothing_tree, /* outlining_inline_function */ > + debug_nothing_tree_tree, /* aliased_decl */ > + debug_nothing_tree_tree, /* trampoline_decl */ > debug_nothing_rtx_code_label, /* label */ > dbxout_handle_pch, /* handle_pch */ > debug_nothing_rtx_insn, /* var_location */ > @@ -412,6 +414,8 @@ const struct gcc_debug_hooks xcoff_debug_hooks = > debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ > debug_nothing_tree, /* deferred_inline_function */ > debug_nothing_tree, /* outlining_inline_function */ > + debug_nothing_tree_tree, /* aliased_decl */ > + debug_nothing_tree_tree, /* trampoline_decl */ > debug_nothing_rtx_code_label, /* label */ > dbxout_handle_pch, /* handle_pch */ > debug_nothing_rtx_insn, /* var_location */ > diff --git a/gcc/debug.c b/gcc/debug.c > index 9c2caae..c9495c9a 100644 > --- a/gcc/debug.c > +++ b/gcc/debug.c > @@ -50,6 +50,8 @@ const struct gcc_debug_hooks do_nothing_debug_hooks = > debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ > debug_nothing_tree, /* deferred_inline_function */ > debug_nothing_tree, /* outlining_inline_function */ > + debug_nothing_tree_tree, /* aliased_decl */ > + debug_nothing_tree_tree, /* trampoline_decl */ > debug_nothing_rtx_code_label, /* label */ > debug_nothing_int, /* handle_pch */ > debug_nothing_rtx_insn, /* var_location */ > diff --git a/gcc/debug.h b/gcc/debug.h > index 6711f8b..cb6218f 100644 > --- a/gcc/debug.h > +++ b/gcc/debug.h > @@ -155,6 +155,14 @@ struct gcc_debug_hooks > the inline before it gets mangled by optimization. */ > void (* outlining_inline_function) (tree decl); > > + /* ALIAS is a declaration whose symbol was defined as an alias to > + DECL's symbol. Called right after outputting the alias > + definition. */ > + void (* aliased_decl) (tree alias, tree decl); > + > + /* TRAMPOLINE is a function defined as a trampoline to DECL. */ > + void (* trampoline_decl) (tree trampoline, tree decl); > + > /* Called from final_scan_insn for any CODE_LABEL insn whose > LABEL_NAME is non-null. */ > void (* label) (rtx_code_label *); > diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c > index d8ca1b7..cba37f9 100644 > --- a/gcc/dwarf2out.c > +++ b/gcc/dwarf2out.c > @@ -2506,6 +2506,8 @@ static void dwarf2out_begin_function (tree); > static void dwarf2out_end_function (unsigned int); > static void dwarf2out_register_main_translation_unit (tree unit); > static void dwarf2out_set_name (tree, tree); > +static void dwarf2out_aliased_decl (tree, tree); > +static void dwarf2out_trampoline_decl (tree, tree); > > /* The debug hooks structure. */ > > @@ -2545,6 +2547,8 @@ const struct gcc_debug_hooks dwarf2_debug_hooks = > emitting the abstract description of inline functions until > something tries to reference them. */ > dwarf2out_abstract_function, /* outlining_inline_function */ > + dwarf2out_aliased_decl, /* aliased_decl */ > + dwarf2out_trampoline_decl, /* trampoline_decl */ > debug_nothing_rtx_code_label, /* label */ > debug_nothing_int, /* handle_pch */ > dwarf2out_var_location, > @@ -2583,6 +2587,8 @@ const struct gcc_debug_hooks dwarf2_lineno_debug_hooks = > debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ > debug_nothing_tree, /* deferred_inline_function */ > debug_nothing_tree, /* outlining_inline_function */ > + debug_nothing_tree_tree, /* aliased_decl */ > + debug_nothing_tree_tree, /* trampoline_decl */ > debug_nothing_rtx_code_label, /* label */ > debug_nothing_int, /* handle_pch */ > debug_nothing_rtx_insn, /* var_location */ > @@ -9755,7 +9761,10 @@ dwarf2_name (tree decl, int scope) > { > if (DECL_NAMELESS (decl)) > return NULL; > - return lang_hooks.dwarf_name (decl, scope ? 1 : 0); > + const char *name = lang_hooks.dwarf_name (decl, scope ? 1 : 0); > + if (name && name[0] == '*') > + name++; > + return name; > } > > /* Add a new entry to .debug_pubnames if appropriate. */ > @@ -23797,6 +23806,95 @@ dwarf2out_imported_module_or_decl (tree decl, tree name, tree context, > dwarf2out_imported_module_or_decl_1 (decl, name, context, scope_die); > } > > +/* Output debug info indicating that ALIAS is an alias to DECL. */ > + > +static void > +dwarf2out_aliased_decl (tree alias, tree decl) > +{ > + if (debug_info_level <= DINFO_LEVEL_TERSE) > + return; > + > + if (!(dwarf_version >= 3 || !dwarf_strict)) > + return; > + > + if (DECL_IGNORED_P (decl) || DECL_IGNORED_P (alias)) > + return; > + > + dw_die_ref decl_die = lookup_decl_die (decl); > + > + if (!decl_die) > + return; > + > + dw_die_ref old_alias_die = lookup_decl_die (alias); > + > + if (old_alias_die && TREE_CODE (alias) == FUNCTION_DECL) > + /* FIXME: we have a specification and probably a definition that > + turned into an alias. Location information of the aliased > + definition is most certainly not suitable for this alias. */ > + return; > + > + dw_die_ref alias_die = new_die (DW_TAG_imported_declaration, > + comp_unit_die (), NULL_TREE); > + > + add_AT_die_ref (alias_die, DW_AT_import, decl_die); > + > + /* ??? It would be nice if we could just link back to the symbol > + declaration, but DW_AT_specification is not a welcome attribute > + for a DW_TAG_imported_declaration. */ > + if (0 && old_alias_die) > + { > + add_AT_die_ref (alias_die, DW_AT_specification, old_alias_die); > + return; > + } > + > + equate_decl_number_to_die (alias, alias_die); > + > + if (TREE_PUBLIC (alias)) > + add_AT_flag (alias_die, DW_AT_external, 1); > + > + { > + bool save_artificial = DECL_ARTIFICIAL (alias); > + /* Temporarily set DECL_ARTIFICIAL so that we don't emit src coords > + attributes. */ > + DECL_ARTIFICIAL (alias) = true; > + add_name_and_src_coords_attributes (alias_die, alias); > + DECL_ARTIFICIAL (alias) = save_artificial; > + } > + > + add_pubname (alias, alias_die); > + if (DECL_ARTIFICIAL (alias)) > + add_AT_flag (alias_die, DW_AT_artificial, 1); > + add_accessibility_attribute (alias_die, alias); > +} > + > +/* Output debug info indicating that TRAMPOLINE is a trampoline to > + DECL. */ > + > +static void > +dwarf2out_trampoline_decl (tree trampoline, tree decl) > +{ > + if (debug_info_level <= DINFO_LEVEL_TERSE) > + return; > + > + if (!(dwarf_version >= 3 || !dwarf_strict)) > + return; > + > + if (DECL_IGNORED_P (decl) || DECL_IGNORED_P (trampoline)) > + return; > + > + dw_die_ref decl_die = lookup_decl_die (decl); > + > + if (!decl_die) > + return; > + > + dw_die_ref trampoline_die = lookup_decl_die (trampoline); > + > + if (!trampoline_die) > + return; > + > + add_AT_die_ref (trampoline_die, DW_AT_trampoline, decl_die); > +} > + > /* Output debug information for namelists. */ > > static dw_die_ref > diff --git a/gcc/sdbout.c b/gcc/sdbout.c > index dc52716..df26ad8 100644 > --- a/gcc/sdbout.c > +++ b/gcc/sdbout.c > @@ -301,6 +301,8 @@ const struct gcc_debug_hooks sdb_debug_hooks = > debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ > debug_nothing_tree, /* deferred_inline_function */ > debug_nothing_tree, /* outlining_inline_function */ > + debug_nothing_tree_tree, /* aliased_decl */ > + debug_nothing_tree_tree, /* trampoline_decl */ > sdbout_label, /* label */ > debug_nothing_int, /* handle_pch */ > debug_nothing_rtx_insn, /* var_location */ > diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-1.C b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-1.C > index c0d3d22..71efae8 100644 > --- a/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-1.C > +++ b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-1.C > @@ -14,4 +14,4 @@ main() > K k; > } > > -// { dg-final {scan-assembler-times " DW_AT_\[MIPS_\]*linkage_name" 4 } } > +// { dg-final {scan-assembler-times " DW_AT_\[MIPS_\]*linkage_name" 6 } } > diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-2.C b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-2.C > new file mode 100644 > index 0000000..0737e43 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-2.C > @@ -0,0 +1,13 @@ > +// { dg-options "-gdwarf-2 -dA" } > +/* { dg-require-alias "" } */ > +// { dg-do compile } > + > +struct foo { > + foo (); > + ~foo (); > +}; > + > +foo::foo () {} > +foo::~foo () {} > + > +// { dg-final { scan-assembler-times " DW_AT_import" 2 } } > diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-3.C b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-3.C > new file mode 100644 > index 0000000..d500e82 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-3.C > @@ -0,0 +1,17 @@ > +// { dg-options "-gdwarf-2 -fdeclone-ctor-dtor -dA" } > +// { dg-do compile } > + > +struct bar { > + bar (); > + ~bar (); > +}; > + > +struct foo : virtual bar { > + foo (); > + ~foo (); > +}; > + > +foo::foo () {} > +foo::~foo () {} > + > +// { dg-final { scan-assembler-times " DW_AT_trampoline" 4 } } > diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/covariant-1.C b/gcc/testsuite/g++.dg/debug/dwarf2/covariant-1.C > new file mode 100644 > index 0000000..1f4326a > --- /dev/null > +++ b/gcc/testsuite/g++.dg/debug/dwarf2/covariant-1.C > @@ -0,0 +1,24 @@ > +// { dg-options "-gdwarf-2 -dA" } > +/* { dg-require-alias "" } */ > +// { dg-do compile } > + > +class A { > +public: > + virtual A* getThis(); > +}; > + > +class B { > + int a; > +public: > + virtual B* getThis(); > +}; > + > +class AB : public A, public B { > +public: > + virtual AB* getThis(); > +}; > + > +AB* AB::getThis() { return this; } > + > +// { dg-final { scan-assembler-times " DW_AT_import" 2 } } > +// { dg-final { scan-assembler-times " DW_AT_trampoline" 1 } } > diff --git a/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-1.c b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-1.c > new file mode 100644 > index 0000000..9968856 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-1.c > @@ -0,0 +1,10 @@ > +/* { dg-do compile } */ > +/* { dg-require-alias "" } */ > +/* { dg-options "-gdwarf-2 -dA" } */ > + > +static int f1 (void) { return 0; } > +extern int g1 (void) __attribute__((__alias__("f1"))); > + > +int f () { return g1 (); } > + > +// { dg-final { scan-assembler-times " DW_AT_import" 1 } } > diff --git a/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-2.c b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-2.c > new file mode 100644 > index 0000000..27201d4 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-2.c > @@ -0,0 +1,10 @@ > +/* { dg-do compile } */ > +/* { dg-require-alias "" } */ > +/* { dg-options "-gdwarf-2 -dA" } */ > + > +static int i1 = 0; > +extern int i2 __attribute__((__alias__("i1"))); > + > +int f () { return i2; } > + > +// { dg-final { scan-assembler-times " DW_AT_import" 1 } } > diff --git a/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-1.c b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-1.c > new file mode 100644 > index 0000000..b53bd05 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-1.c > @@ -0,0 +1,10 @@ > +/* { dg-do compile } */ > +/* { dg-require-weak "" } */ > +/* { dg-options "-gdwarf-2 -dA" } */ > + > +int f1 (void) { return 0; } > +static int g1 (void) __attribute__((__weakref__("f1"))); > + > +int f () { return g1 (); } > + > +// { dg-final { scan-assembler-times " DW_AT_import" 1 } } > diff --git a/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-2.c b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-2.c > new file mode 100644 > index 0000000..6020202 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-2.c > @@ -0,0 +1,10 @@ > +/* { dg-do compile } */ > +/* { dg-require-weak "" } */ > +/* { dg-options "-gdwarf-2 -dA" } */ > + > +int i1 = 0; > +static int i2 __attribute__((__weakref__("i1"))); > + > +int f () { return i2; } > + > +// { dg-final { scan-assembler-times " DW_AT_import" 1 } } > diff --git a/gcc/varpool.c b/gcc/varpool.c > index cbbdda4..878aaee 100644 > --- a/gcc/varpool.c > +++ b/gcc/varpool.c > @@ -538,8 +538,12 @@ varpool_node::assemble_aliases (void) > { > varpool_node *alias = dyn_cast <varpool_node *> (ref->referring); > if (!alias->transparent_alias) > - do_assemble_alias (alias->decl, > - DECL_ASSEMBLER_NAME (decl)); > + { > + do_assemble_alias (alias->decl, > + DECL_ASSEMBLER_NAME (decl)); > + if (!DECL_IGNORED_P (alias->decl) && !DECL_IGNORED_P (decl)) > + (*debug_hooks->aliased_decl) (alias->decl, decl); > + } > alias->assemble_aliases (); > } > } > diff --git a/gcc/vmsdbgout.c b/gcc/vmsdbgout.c > index 7c6d64d..fc87828 100644 > --- a/gcc/vmsdbgout.c > +++ b/gcc/vmsdbgout.c > @@ -198,6 +198,8 @@ const struct gcc_debug_hooks vmsdbg_debug_hooks > debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ > debug_nothing_tree, /* deferred_inline_function */ > vmsdbgout_abstract_function, > + debug_nothing_tree_tree, /* aliased_decl */ > + debug_nothing_tree_tree, /* trampoline_decl */ > debug_nothing_rtx_code_label, /* label */ > debug_nothing_int, /* handle_pch */ > debug_nothing_rtx_insn, /* var_location */ > > > -- > Alexandre Oliva, freedom fighter http://FSFLA.org/~lxoliva/ > You must be the change you wish to see in the world. -- Gandhi > Be Free! -- http://FSFLA.org/ FSF Latin America board member > Free Software Evangelist|Red Hat Brasil GNU Toolchain Engineer
Hi, Richard, Thanks for the feedback. I'm afraid I can't quite figure out what you're getting at. Please see below. On Feb 22, 2016, Richard Biener <richard.guenther@gmail.com> wrote: > I think this breaks early-debug assumptions in creating new decl DIEs > rather than just annotating old ones. Can you elaborate on it, or point at where these assumptions you allude to are documented? I'm afraid I can't even tell whether the problem you allude to has to do with users of the debug hooks interface or the dwarf2out implementation thereof. Sure enough, we haven't created DIEs for user-introduced or C++ cdtor aliases before, so there are no DIEs for us to annotate, and there are no other uses of the debug hooks interface related with them, that could possibly interfere with them. Conversely, alias decls for which we *have* created DIEs are ones that cgraph turned into aliases; we do NOT want to pretend they're the same function, and ideally we'd emit separate debug information for them, but we can't retroactively figure out blocks, line numbers, variable locations and whatnot for the unrelated function that happened to optimize to the same executable code. The best we can do for such aliases ATM is to leave them alone; that's unchanged. > So assemble_aliases is the wrong spot to do this. Here, you seem to be talking about *users* of the debug hooks interface. But then, I'd argue that the fact that debug info for aliases in dwarf2out is implemented as DIEs is an internal implementation detail, so why should assumptions made by the user side of the interface matter?
On Wed, Feb 24, 2016 at 5:07 AM, Alexandre Oliva <aoliva@redhat.com> wrote: > Hi, Richard, > > Thanks for the feedback. I'm afraid I can't quite figure out what > you're getting at. Please see below. > > On Feb 22, 2016, Richard Biener <richard.guenther@gmail.com> wrote: > >> I think this breaks early-debug assumptions in creating new decl DIEs >> rather than just annotating old ones. > > Can you elaborate on it, or point at where these assumptions you allude > to are documented? I'm afraid I can't even tell whether the problem you > allude to has to do with users of the debug hooks interface or the > dwarf2out implementation thereof. > > Sure enough, we haven't created DIEs for user-introduced or C++ cdtor > aliases before, so there are no DIEs for us to annotate, and there are > no other uses of the debug hooks interface related with them, that could > possibly interfere with them. > > Conversely, alias decls for which we *have* created DIEs are ones that > cgraph turned into aliases; we do NOT want to pretend they're the same > function, and ideally we'd emit separate debug information for them, but > we can't retroactively figure out blocks, line numbers, variable > locations and whatnot for the unrelated function that happened to > optimize to the same executable code. The best we can do for such > aliases ATM is to leave them alone; that's unchanged. > >> So assemble_aliases is the wrong spot to do this. > > Here, you seem to be talking about *users* of the debug hooks interface. > But then, I'd argue that the fact that debug info for aliases in > dwarf2out is implemented as DIEs is an internal implementation detail, > so why should assumptions made by the user side of the interface matter? early-debug means that when dwarf2out_early_finish runs we have created all type and decl DIEs. From thereon only things like location expressions should be added to existing DIEs. So I was chiming in to see whether the added DIEs may cause any issue when going forward with dropping frontends after dwarf2out_early_finish. The function_decl call in expand_thunk looks dangerous, the new hooks are self-contained enough that those late DIEs should (hopefully) cause no issues (they can be seen as annotating an exiting DIE). Richard. > -- > Alexandre Oliva, freedom fighter http://FSFLA.org/~lxoliva/ > You must be the change you wish to see in the world. -- Gandhi > Be Free! -- http://FSFLA.org/ FSF Latin America board member > Free Software Evangelist|Red Hat Brasil GNU Toolchain Engineer
diff --git a/gcc/cgraph.h b/gcc/cgraph.h index fc7bb22..4d8bf05 100644 --- a/gcc/cgraph.h +++ b/gcc/cgraph.h @@ -1117,6 +1117,10 @@ public: external means. */ inline void mark_force_output (void); + /* Return true when function is a language-defined trampoline, e.g., + C++ ctor and dtor "thunks" that just call the unified cdtor. */ + bool is_lang_trampoline (void); + /* Return true when function can be marked local. */ bool local_p (void); diff --git a/gcc/cgraphunit.c b/gcc/cgraphunit.c index 0a745f0..b399d61 100644 --- a/gcc/cgraphunit.c +++ b/gcc/cgraphunit.c @@ -203,6 +203,7 @@ along with GCC; see the file COPYING3. If not see #include "dbgcnt.h" #include "tree-chkp.h" #include "lto-section-names.h" +#include "demangle.h" /* Queue of cgraph nodes scheduled to be added into cgraph. This is a secondary queue used during optimization to accommodate passes that @@ -1635,6 +1636,12 @@ cgraph_node::expand_thunk (bool output_asm_thunks, bool force_gimple_thunk) assemble_end_function (thunk_fndecl, fnname); insn_locations_finalize (); init_insn_lengths (); + + timevar_push (TV_SYMOUT); + if (!DECL_IGNORED_P (thunk_fndecl)) + (*debug_hooks->function_decl) (thunk_fndecl); + timevar_pop (TV_SYMOUT); + free_after_compilation (cfun); TREE_ASM_WRITTEN (thunk_fndecl) = 1; thunk.thunk_p = false; @@ -1676,7 +1683,6 @@ cgraph_node::expand_thunk (bool output_asm_thunks, bool force_gimple_thunk) resolve_unique_section (thunk_fndecl, 0, flag_function_sections); - DECL_IGNORED_P (thunk_fndecl) = 1; bitmap_obstack_initialize (NULL); if (thunk.virtual_offset_p) @@ -1889,6 +1895,92 @@ cgraph_node::expand_thunk (bool output_asm_thunks, bool force_gimple_thunk) return true; } +/* Return true if DECL is a cdtor trampoline for unified cdtor + TARGET. */ + +static bool +cxx_cdtor_trampoline_p (tree decl, tree target) +{ + if (DECL_ABSTRACT_ORIGIN (decl)) + return false; + + if (!DECL_CXX_CONSTRUCTOR_P (decl) && !DECL_CXX_DESTRUCTOR_P (decl)) + return false; + + if (DECL_CXX_CONSTRUCTOR_P (decl) != DECL_CXX_CONSTRUCTOR_P (target)) + return false; + + if (DECL_CXX_DESTRUCTOR_P (decl) != DECL_CXX_DESTRUCTOR_P (target)) + return false; + + gcc_assert (DECL_ASSEMBLER_NAME_SET_P (decl)); + gcc_assert (DECL_ASSEMBLER_NAME_SET_P (target)); + + const char *dname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); + const char *tname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (target)); + + unsigned int i = strlen (dname); + if (i != strlen (tname)) + return false; + + gcc_assert (i); + + /* C1 and C2 ctors may be trampolines to C4; D0, D1 and D2 dtors may + be trampolines to D4. Check their mangled names, so that the + test will work even during LTO compilations, when the cdtor + clones retrofitted into trampolines might not be right after the + unified one in the DECL_CHAIN, and we don't have C++-specific + data structures or lang hooks to check that the cdtors are of + different kinds and belong to the same class. + + Alas, just checking that the assembler name has e.g. C2 vs C4 as + the only difference could find false positives, e.g., if there + are cdtors with the same signature (aside from the THIS pointer) + in classes whose names contain C2 and C4, say _ZN2C2C1Ev AKA + C2::C2() and _ZN2C4C1Ev AKA C4::C4(). + + So, after checking that we found viable distinguishing characters + at the expected place, we check that the cdtors are of different + kinds using the demangler. Yuck. */ + bool found = false; + while (i--) + if (dname[i] != tname[i]) + { + if (!found + && tname[i] == '4' && i && tname[i-1] == dname[i-1] + && (((dname[i-1] == 'C' || dname[i-1] == 'D') + && (dname[i] == '1' || dname[i] == '2')) + || (dname[i-1] == 'D' && dname[i] == '0'))) + found = true; + else + return false; + } + + if (DECL_CXX_CONSTRUCTOR_P (decl)) + return is_gnu_v3_mangled_ctor (tname) == gnu_v3_unified_ctor + && is_gnu_v3_mangled_ctor (dname) != gnu_v3_unified_ctor; + else if (DECL_CXX_DESTRUCTOR_P (decl)) + return is_gnu_v3_mangled_dtor (tname) == gnu_v3_unified_dtor + && is_gnu_v3_mangled_dtor (dname) != gnu_v3_unified_dtor; + else + gcc_unreachable (); +} + +/* Return true when function is as a language-defined trampoline, + e.g., C++ ctor and dtor "thunks" that just call the unified + cdtor. */ + +bool +cgraph_node::is_lang_trampoline (void) +{ + if (!callees || callees->next_callee) + return false; + + tree target = callees->callee->decl; + + return (cxx_cdtor_trampoline_p (decl, target)); +} + /* Assemble thunks and aliases associated to node. */ void @@ -1906,9 +1998,17 @@ cgraph_node::assemble_thunks_and_aliases (void) e = e->next_caller; thunk->expand_thunk (true, false); thunk->assemble_thunks_and_aliases (); + if (!DECL_IGNORED_P (thunk->decl) && !DECL_IGNORED_P (decl)) + (*debug_hooks->trampoline_decl) (thunk->decl, decl); } else - e = e->next_caller; + { + if (e->caller->is_lang_trampoline () + && !DECL_IGNORED_P (e->caller->decl) && !DECL_IGNORED_P (decl)) + (*debug_hooks->trampoline_decl) (e->caller->decl, decl); + + e = e->next_caller; + } FOR_EACH_ALIAS (this, ref) { @@ -1922,6 +2022,8 @@ cgraph_node::assemble_thunks_and_aliases (void) TREE_ASM_WRITTEN (decl) = 1; do_assemble_alias (alias->decl, DECL_ASSEMBLER_NAME (decl)); + if (!DECL_IGNORED_P (alias->decl) && !DECL_IGNORED_P (decl)) + (*debug_hooks->aliased_decl) (alias->decl, decl); alias->assemble_thunks_and_aliases (); TREE_ASM_WRITTEN (decl) = saved_written; } @@ -2341,7 +2443,7 @@ symbol_table::output_weakrefs (void) || !TREE_ASM_WRITTEN (cnode->instrumented_version->decl)) && node->weakref) { - tree target; + tree target, target_decl; /* Weakrefs are special by not requiring target definition in current compilation unit. It is thus bit hard to work out what we want to @@ -2349,17 +2451,33 @@ symbol_table::output_weakrefs (void) When alias target is defined, we need to fetch it from symtab reference, otherwise it is pointed to by alias_target. */ if (node->alias_target) - target = (DECL_P (node->alias_target) - ? DECL_ASSEMBLER_NAME (node->alias_target) - : node->alias_target); + { + if (DECL_P (node->alias_target)) + { + target_decl = node->alias_target; + target = DECL_ASSEMBLER_NAME (target_decl); + } + else + { + target_decl = NULL_TREE; + target = node->alias_target; + } + } else if (node->analyzed) - target = DECL_ASSEMBLER_NAME (node->get_alias_target ()->decl); + { + target_decl = node->get_alias_target ()->decl; + target = DECL_ASSEMBLER_NAME (target_decl); + } else { gcc_unreachable (); - target = get_alias_symbol (node->decl); + target_decl = node->decl; + target = get_alias_symbol (target_decl); } do_assemble_alias (node->decl, target); + if (target_decl && !DECL_IGNORED_P (node->decl) + && !DECL_IGNORED_P (target_decl)) + (*debug_hooks->aliased_decl) (node->decl, target_decl); } } diff --git a/gcc/cp/method.c b/gcc/cp/method.c index e358ebd..24872d1 100644 --- a/gcc/cp/method.c +++ b/gcc/cp/method.c @@ -219,6 +219,7 @@ make_alias_for (tree target, tree newid) } DECL_EXTERNAL (alias) = 0; DECL_ARTIFICIAL (alias) = 1; + DECL_IGNORED_P (alias) = DECL_IGNORED_P (target); DECL_TEMPLATE_INSTANTIATED (alias) = 0; if (TREE_CODE (alias) == FUNCTION_DECL) { diff --git a/gcc/dbxout.c b/gcc/dbxout.c index 25a03ef..8da8eb0 100644 --- a/gcc/dbxout.c +++ b/gcc/dbxout.c @@ -372,6 +372,8 @@ const struct gcc_debug_hooks dbx_debug_hooks = debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ debug_nothing_tree, /* deferred_inline_function */ debug_nothing_tree, /* outlining_inline_function */ + debug_nothing_tree_tree, /* aliased_decl */ + debug_nothing_tree_tree, /* trampoline_decl */ debug_nothing_rtx_code_label, /* label */ dbxout_handle_pch, /* handle_pch */ debug_nothing_rtx_insn, /* var_location */ @@ -412,6 +414,8 @@ const struct gcc_debug_hooks xcoff_debug_hooks = debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ debug_nothing_tree, /* deferred_inline_function */ debug_nothing_tree, /* outlining_inline_function */ + debug_nothing_tree_tree, /* aliased_decl */ + debug_nothing_tree_tree, /* trampoline_decl */ debug_nothing_rtx_code_label, /* label */ dbxout_handle_pch, /* handle_pch */ debug_nothing_rtx_insn, /* var_location */ diff --git a/gcc/debug.c b/gcc/debug.c index 9c2caae..c9495c9a 100644 --- a/gcc/debug.c +++ b/gcc/debug.c @@ -50,6 +50,8 @@ const struct gcc_debug_hooks do_nothing_debug_hooks = debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ debug_nothing_tree, /* deferred_inline_function */ debug_nothing_tree, /* outlining_inline_function */ + debug_nothing_tree_tree, /* aliased_decl */ + debug_nothing_tree_tree, /* trampoline_decl */ debug_nothing_rtx_code_label, /* label */ debug_nothing_int, /* handle_pch */ debug_nothing_rtx_insn, /* var_location */ diff --git a/gcc/debug.h b/gcc/debug.h index 6711f8b..cb6218f 100644 --- a/gcc/debug.h +++ b/gcc/debug.h @@ -155,6 +155,14 @@ struct gcc_debug_hooks the inline before it gets mangled by optimization. */ void (* outlining_inline_function) (tree decl); + /* ALIAS is a declaration whose symbol was defined as an alias to + DECL's symbol. Called right after outputting the alias + definition. */ + void (* aliased_decl) (tree alias, tree decl); + + /* TRAMPOLINE is a function defined as a trampoline to DECL. */ + void (* trampoline_decl) (tree trampoline, tree decl); + /* Called from final_scan_insn for any CODE_LABEL insn whose LABEL_NAME is non-null. */ void (* label) (rtx_code_label *); diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c index d8ca1b7..cba37f9 100644 --- a/gcc/dwarf2out.c +++ b/gcc/dwarf2out.c @@ -2506,6 +2506,8 @@ static void dwarf2out_begin_function (tree); static void dwarf2out_end_function (unsigned int); static void dwarf2out_register_main_translation_unit (tree unit); static void dwarf2out_set_name (tree, tree); +static void dwarf2out_aliased_decl (tree, tree); +static void dwarf2out_trampoline_decl (tree, tree); /* The debug hooks structure. */ @@ -2545,6 +2547,8 @@ const struct gcc_debug_hooks dwarf2_debug_hooks = emitting the abstract description of inline functions until something tries to reference them. */ dwarf2out_abstract_function, /* outlining_inline_function */ + dwarf2out_aliased_decl, /* aliased_decl */ + dwarf2out_trampoline_decl, /* trampoline_decl */ debug_nothing_rtx_code_label, /* label */ debug_nothing_int, /* handle_pch */ dwarf2out_var_location, @@ -2583,6 +2587,8 @@ const struct gcc_debug_hooks dwarf2_lineno_debug_hooks = debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ debug_nothing_tree, /* deferred_inline_function */ debug_nothing_tree, /* outlining_inline_function */ + debug_nothing_tree_tree, /* aliased_decl */ + debug_nothing_tree_tree, /* trampoline_decl */ debug_nothing_rtx_code_label, /* label */ debug_nothing_int, /* handle_pch */ debug_nothing_rtx_insn, /* var_location */ @@ -9755,7 +9761,10 @@ dwarf2_name (tree decl, int scope) { if (DECL_NAMELESS (decl)) return NULL; - return lang_hooks.dwarf_name (decl, scope ? 1 : 0); + const char *name = lang_hooks.dwarf_name (decl, scope ? 1 : 0); + if (name && name[0] == '*') + name++; + return name; } /* Add a new entry to .debug_pubnames if appropriate. */ @@ -23797,6 +23806,95 @@ dwarf2out_imported_module_or_decl (tree decl, tree name, tree context, dwarf2out_imported_module_or_decl_1 (decl, name, context, scope_die); } +/* Output debug info indicating that ALIAS is an alias to DECL. */ + +static void +dwarf2out_aliased_decl (tree alias, tree decl) +{ + if (debug_info_level <= DINFO_LEVEL_TERSE) + return; + + if (!(dwarf_version >= 3 || !dwarf_strict)) + return; + + if (DECL_IGNORED_P (decl) || DECL_IGNORED_P (alias)) + return; + + dw_die_ref decl_die = lookup_decl_die (decl); + + if (!decl_die) + return; + + dw_die_ref old_alias_die = lookup_decl_die (alias); + + if (old_alias_die && TREE_CODE (alias) == FUNCTION_DECL) + /* FIXME: we have a specification and probably a definition that + turned into an alias. Location information of the aliased + definition is most certainly not suitable for this alias. */ + return; + + dw_die_ref alias_die = new_die (DW_TAG_imported_declaration, + comp_unit_die (), NULL_TREE); + + add_AT_die_ref (alias_die, DW_AT_import, decl_die); + + /* ??? It would be nice if we could just link back to the symbol + declaration, but DW_AT_specification is not a welcome attribute + for a DW_TAG_imported_declaration. */ + if (0 && old_alias_die) + { + add_AT_die_ref (alias_die, DW_AT_specification, old_alias_die); + return; + } + + equate_decl_number_to_die (alias, alias_die); + + if (TREE_PUBLIC (alias)) + add_AT_flag (alias_die, DW_AT_external, 1); + + { + bool save_artificial = DECL_ARTIFICIAL (alias); + /* Temporarily set DECL_ARTIFICIAL so that we don't emit src coords + attributes. */ + DECL_ARTIFICIAL (alias) = true; + add_name_and_src_coords_attributes (alias_die, alias); + DECL_ARTIFICIAL (alias) = save_artificial; + } + + add_pubname (alias, alias_die); + if (DECL_ARTIFICIAL (alias)) + add_AT_flag (alias_die, DW_AT_artificial, 1); + add_accessibility_attribute (alias_die, alias); +} + +/* Output debug info indicating that TRAMPOLINE is a trampoline to + DECL. */ + +static void +dwarf2out_trampoline_decl (tree trampoline, tree decl) +{ + if (debug_info_level <= DINFO_LEVEL_TERSE) + return; + + if (!(dwarf_version >= 3 || !dwarf_strict)) + return; + + if (DECL_IGNORED_P (decl) || DECL_IGNORED_P (trampoline)) + return; + + dw_die_ref decl_die = lookup_decl_die (decl); + + if (!decl_die) + return; + + dw_die_ref trampoline_die = lookup_decl_die (trampoline); + + if (!trampoline_die) + return; + + add_AT_die_ref (trampoline_die, DW_AT_trampoline, decl_die); +} + /* Output debug information for namelists. */ static dw_die_ref diff --git a/gcc/sdbout.c b/gcc/sdbout.c index dc52716..df26ad8 100644 --- a/gcc/sdbout.c +++ b/gcc/sdbout.c @@ -301,6 +301,8 @@ const struct gcc_debug_hooks sdb_debug_hooks = debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ debug_nothing_tree, /* deferred_inline_function */ debug_nothing_tree, /* outlining_inline_function */ + debug_nothing_tree_tree, /* aliased_decl */ + debug_nothing_tree_tree, /* trampoline_decl */ sdbout_label, /* label */ debug_nothing_int, /* handle_pch */ debug_nothing_rtx_insn, /* var_location */ diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-1.C b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-1.C index c0d3d22..71efae8 100644 --- a/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-1.C +++ b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-1.C @@ -14,4 +14,4 @@ main() K k; } -// { dg-final {scan-assembler-times " DW_AT_\[MIPS_\]*linkage_name" 4 } } +// { dg-final {scan-assembler-times " DW_AT_\[MIPS_\]*linkage_name" 6 } } diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-2.C b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-2.C new file mode 100644 index 0000000..0737e43 --- /dev/null +++ b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-2.C @@ -0,0 +1,13 @@ +// { dg-options "-gdwarf-2 -dA" } +/* { dg-require-alias "" } */ +// { dg-do compile } + +struct foo { + foo (); + ~foo (); +}; + +foo::foo () {} +foo::~foo () {} + +// { dg-final { scan-assembler-times " DW_AT_import" 2 } } diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-3.C b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-3.C new file mode 100644 index 0000000..d500e82 --- /dev/null +++ b/gcc/testsuite/g++.dg/debug/dwarf2/cdtor-3.C @@ -0,0 +1,17 @@ +// { dg-options "-gdwarf-2 -fdeclone-ctor-dtor -dA" } +// { dg-do compile } + +struct bar { + bar (); + ~bar (); +}; + +struct foo : virtual bar { + foo (); + ~foo (); +}; + +foo::foo () {} +foo::~foo () {} + +// { dg-final { scan-assembler-times " DW_AT_trampoline" 4 } } diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/covariant-1.C b/gcc/testsuite/g++.dg/debug/dwarf2/covariant-1.C new file mode 100644 index 0000000..1f4326a --- /dev/null +++ b/gcc/testsuite/g++.dg/debug/dwarf2/covariant-1.C @@ -0,0 +1,24 @@ +// { dg-options "-gdwarf-2 -dA" } +/* { dg-require-alias "" } */ +// { dg-do compile } + +class A { +public: + virtual A* getThis(); +}; + +class B { + int a; +public: + virtual B* getThis(); +}; + +class AB : public A, public B { +public: + virtual AB* getThis(); +}; + +AB* AB::getThis() { return this; } + +// { dg-final { scan-assembler-times " DW_AT_import" 2 } } +// { dg-final { scan-assembler-times " DW_AT_trampoline" 1 } } diff --git a/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-1.c b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-1.c new file mode 100644 index 0000000..9968856 --- /dev/null +++ b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-1.c @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-require-alias "" } */ +/* { dg-options "-gdwarf-2 -dA" } */ + +static int f1 (void) { return 0; } +extern int g1 (void) __attribute__((__alias__("f1"))); + +int f () { return g1 (); } + +// { dg-final { scan-assembler-times " DW_AT_import" 1 } } diff --git a/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-2.c b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-2.c new file mode 100644 index 0000000..27201d4 --- /dev/null +++ b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-alias-2.c @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-require-alias "" } */ +/* { dg-options "-gdwarf-2 -dA" } */ + +static int i1 = 0; +extern int i2 __attribute__((__alias__("i1"))); + +int f () { return i2; } + +// { dg-final { scan-assembler-times " DW_AT_import" 1 } } diff --git a/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-1.c b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-1.c new file mode 100644 index 0000000..b53bd05 --- /dev/null +++ b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-1.c @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-require-weak "" } */ +/* { dg-options "-gdwarf-2 -dA" } */ + +int f1 (void) { return 0; } +static int g1 (void) __attribute__((__weakref__("f1"))); + +int f () { return g1 (); } + +// { dg-final { scan-assembler-times " DW_AT_import" 1 } } diff --git a/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-2.c b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-2.c new file mode 100644 index 0000000..6020202 --- /dev/null +++ b/gcc/testsuite/gcc.dg/debug/dwarf2/attr-weakref-2.c @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-require-weak "" } */ +/* { dg-options "-gdwarf-2 -dA" } */ + +int i1 = 0; +static int i2 __attribute__((__weakref__("i1"))); + +int f () { return i2; } + +// { dg-final { scan-assembler-times " DW_AT_import" 1 } } diff --git a/gcc/varpool.c b/gcc/varpool.c index cbbdda4..878aaee 100644 --- a/gcc/varpool.c +++ b/gcc/varpool.c @@ -538,8 +538,12 @@ varpool_node::assemble_aliases (void) { varpool_node *alias = dyn_cast <varpool_node *> (ref->referring); if (!alias->transparent_alias) - do_assemble_alias (alias->decl, - DECL_ASSEMBLER_NAME (decl)); + { + do_assemble_alias (alias->decl, + DECL_ASSEMBLER_NAME (decl)); + if (!DECL_IGNORED_P (alias->decl) && !DECL_IGNORED_P (decl)) + (*debug_hooks->aliased_decl) (alias->decl, decl); + } alias->assemble_aliases (); } } diff --git a/gcc/vmsdbgout.c b/gcc/vmsdbgout.c index 7c6d64d..fc87828 100644 --- a/gcc/vmsdbgout.c +++ b/gcc/vmsdbgout.c @@ -198,6 +198,8 @@ const struct gcc_debug_hooks vmsdbg_debug_hooks debug_nothing_tree_tree_tree_bool, /* imported_module_or_decl */ debug_nothing_tree, /* deferred_inline_function */ vmsdbgout_abstract_function, + debug_nothing_tree_tree, /* aliased_decl */ + debug_nothing_tree_tree, /* trampoline_decl */ debug_nothing_rtx_code_label, /* label */ debug_nothing_int, /* handle_pch */ debug_nothing_rtx_insn, /* var_location */