public inbox for gcc-cvs@sourceware.org
help / color / mirror / Atom feed
* [gcc r14-9374] c++/modules: member alias tmpl partial inst [PR103994]
@ 2024-03-07 21:39 Patrick Palka
0 siblings, 0 replies; only message in thread
From: Patrick Palka @ 2024-03-07 21:39 UTC (permalink / raw)
To: gcc-cvs
https://gcc.gnu.org/g:f5c1224708a0cf9cc2770c44bbbe7d0c883942be
commit r14-9374-gf5c1224708a0cf9cc2770c44bbbe7d0c883942be
Author: Patrick Palka <ppalka@redhat.com>
Date: Thu Mar 7 16:39:20 2024 -0500
c++/modules: member alias tmpl partial inst [PR103994]
Alias templates are weird in that their specializations can appear in
both decl_specializations and type_specializations. They're always in
the decl table, and additionally appear in the type table only at parse
time via finish_template_type. There seems to be no good reason for
them to appear in both tables, and the code paths end up stepping over
each other in particular for a partial instantiation such as
A<B>::key_arg<T> in the below modules testcase: the type code path
(lookup_template_class) wants to set TI_TEMPLATE to the most general
template whereas the decl code path (tsubst_template_decl called during
instantiation of A<B>) already set TI_TEMPLATE to the partially
instantiated TEMPLATE_DECL. This TI_TEMPLATE change ends up confusing
modules which decides to stream the logically equivalent TYPE_DECL and
TEMPLATE_DECL for this partial instantiation separately.
This patch fixes this by making lookup_template_class dispatch to
instantiate_alias_template early for alias template specializations.
In turn we now add such specializations only to the decl table. This
admits some nice simplification in the modules code which otherwise has
to cope with such specializations appearing in both tables.
PR c++/103994
gcc/cp/ChangeLog:
* cp-tree.h (add_mergeable_specialization): Remove second
parameter.
* module.cc (depset::disc_bits::DB_ALIAS_TMPL_INST_BIT): Remove.
(depset::disc_bits::DB_ALIAS_SPEC_BIT): Remove.
(depset::is_alias_tmpl_inst): Remove.
(depset::is_alias): Remove.
(merge_kind::MK_tmpl_alias_mask): Remove.
(merge_kind::MK_alias_spec): Remove.
(merge_kind_name): Remove entries for alias specializations.
(trees_out::core_vals) <case TEMPLATE_DECL>: Adjust after
removing is_alias_tmpl_inst.
(trees_in::decl_value): Adjust add_mergeable_specialization
calls.
(trees_out::get_merge_kind) <case depset::EK_SPECIALIZATION>:
Use MK_decl_spec for alias template specializations.
(trees_out::key_mergeable): Simplify after MK_tmpl_alias_mask
removal.
(depset::hash::make_dependency): Adjust after removing
DB_ALIAS_TMPL_INST_BIT.
(specialization_add): Don't allow alias templates when !decl_p.
(depset::hash::add_specializations): Remove now-dead code
accomodating alias template specializations in the type table.
* pt.cc (lookup_template_class): Dispatch early to
instantiate_alias_template for alias templates. Simplify
accordingly.
(add_mergeable_specialization): Remove alias_p parameter and
simplify accordingly.
gcc/testsuite/ChangeLog:
* g++.dg/modules/pr99425-1_b.H: s/alias/decl in dump scan.
* g++.dg/modules/tpl-alias-1_a.H: Likewise.
* g++.dg/modules/tpl-alias-2_a.H: New test.
* g++.dg/modules/tpl-alias-2_b.C: New test.
Reviewed-by: Jason Merrill <jason@redhat.com>
Diff:
---
gcc/cp/cp-tree.h | 3 +-
gcc/cp/module.cc | 86 ++++++----------------------
gcc/cp/pt.cc | 84 +++++++++++----------------
gcc/testsuite/g++.dg/modules/pr99425-1_b.H | 2 +-
gcc/testsuite/g++.dg/modules/tpl-alias-1_a.H | 2 +-
gcc/testsuite/g++.dg/modules/tpl-alias-2_a.H | 15 +++++
gcc/testsuite/g++.dg/modules/tpl-alias-2_b.C | 9 +++
7 files changed, 77 insertions(+), 124 deletions(-)
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index 4469d965ef0..14895bc6585 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -7642,8 +7642,7 @@ extern void walk_specializations (bool,
void *);
extern tree match_mergeable_specialization (bool is_decl, spec_entry *);
extern unsigned get_mergeable_specialization_flags (tree tmpl, tree spec);
-extern void add_mergeable_specialization (bool is_decl, bool is_alias,
- spec_entry *,
+extern void add_mergeable_specialization (bool is_decl, spec_entry *,
tree outer, unsigned);
extern tree add_to_template_args (tree, tree);
extern tree add_outermost_template_args (tree, tree);
diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc
index d52db76f59f..53104753737 100644
--- a/gcc/cp/module.cc
+++ b/gcc/cp/module.cc
@@ -2305,11 +2305,7 @@ private:
DB_HIDDEN_BIT, /* A hidden binding. */
/* The following bits are not independent, but enumerating them is
awkward. */
- DB_ALIAS_TMPL_INST_BIT, /* An alias template instantiation. */
- DB_ALIAS_SPEC_BIT, /* Specialization of an alias template
- (in both spec tables). */
- DB_TYPE_SPEC_BIT, /* Specialization in the type table.
- */
+ DB_TYPE_SPEC_BIT, /* Specialization in the type table. */
DB_FRIEND_SPEC_BIT, /* An instantiated template friend. */
};
@@ -2400,14 +2396,6 @@ public:
{
return get_flag_bit<DB_UNREACHED_BIT> ();
}
- bool is_alias_tmpl_inst () const
- {
- return get_flag_bit<DB_ALIAS_TMPL_INST_BIT> ();
- }
- bool is_alias () const
- {
- return get_flag_bit<DB_ALIAS_SPEC_BIT> ();
- }
bool is_hidden () const
{
return get_flag_bit<DB_HIDDEN_BIT> ();
@@ -2781,13 +2769,11 @@ enum merge_kind
MK_template_mask = 0x10, /* A template specialization. */
MK_tmpl_decl_mask = 0x4, /* In decl table. */
- MK_tmpl_alias_mask = 0x2, /* Also in type table */
MK_tmpl_tmpl_mask = 0x1, /* We want TEMPLATE_DECL. */
MK_type_spec = MK_template_mask,
MK_decl_spec = MK_template_mask | MK_tmpl_decl_mask,
- MK_alias_spec = MK_decl_spec | MK_tmpl_alias_mask,
MK_hwm = 0x20
};
@@ -2805,7 +2791,7 @@ static char const *const merge_kind_name[MK_hwm] =
NULL, NULL,
"decl spec", "decl tmpl spec", /* 20,21 decl (template). */
- "alias spec", "alias tmpl spec", /* 22,23 alias (template). */
+ NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
};
@@ -6350,8 +6336,7 @@ trees_out::core_vals (tree t)
gcc_checking_assert
(TREE_VISITED (((lang_tree_node *)t)->template_decl.arguments));
gcc_checking_assert
- (TREE_VISITED (((lang_tree_node *)t)->template_decl.result)
- || dep_hash->find_dependency (t)->is_alias_tmpl_inst ());
+ (TREE_VISITED (((lang_tree_node *)t)->template_decl.result));
if (DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P (t))
WT (DECL_CHAIN (t));
break;
@@ -8270,16 +8255,13 @@ trees_in::decl_value ()
{
bool is_type = TREE_CODE (inner) == TYPE_DECL;
spec.spec = is_type ? type : inner;
- add_mergeable_specialization (!is_type, false,
- &spec, decl, spec_flags);
+ add_mergeable_specialization (!is_type, &spec, decl, spec_flags);
}
else if (mk & MK_template_mask)
{
bool is_type = !(mk & MK_tmpl_decl_mask);
spec.spec = is_type ? type : mk & MK_tmpl_tmpl_mask ? inner : decl;
- add_mergeable_specialization (!is_type,
- !is_type && mk & MK_tmpl_alias_mask,
- &spec, decl, spec_flags);
+ add_mergeable_specialization (!is_type, &spec, decl, spec_flags);
}
if (NAMESPACE_SCOPE_P (decl)
@@ -8356,7 +8338,7 @@ trees_in::decl_value ()
if (!e)
{
spec.spec = inner;
- add_mergeable_specialization (true, false, &spec, decl, spec_flags);
+ add_mergeable_specialization (true, &spec, decl, spec_flags);
}
else if (e != existing)
set_overrun ();
@@ -10514,8 +10496,6 @@ trees_out::get_merge_kind (tree decl, depset *dep)
mk = MK_friend_spec;
else if (dep->is_type_spec ())
mk = MK_type_spec;
- else if (dep->is_alias ())
- mk = MK_alias_spec;
else
mk = MK_decl_spec;
@@ -10626,11 +10606,6 @@ trees_out::key_mergeable (int tag, merge_kind mk, tree decl, tree inner,
gcc_assert (existing);
if (mk & MK_tmpl_decl_mask)
{
- if (mk & MK_tmpl_alias_mask)
- /* It should be in both tables. */
- gcc_checking_assert
- (same_type_p (match_mergeable_specialization (false, entry),
- TREE_TYPE (existing)));
if (mk & MK_tmpl_tmpl_mask)
existing = DECL_TI_TEMPLATE (existing);
}
@@ -12716,17 +12691,12 @@ depset::hash::make_dependency (tree decl, entity_kind ek)
bindings. */
*slot = dep = make_entity (decl, ek, has_def);
- if (TREE_CODE (decl) == TEMPLATE_DECL)
- {
- if (DECL_ALIAS_TEMPLATE_P (decl) && DECL_TEMPLATE_INFO (decl))
- dep->set_flag_bit<DB_ALIAS_TMPL_INST_BIT> ();
- else if (CHECKING_P)
- /* The template_result should otherwise not be in the
- table, or be an empty redirect (created above). */
- if (auto *eslot = entity_slot (DECL_TEMPLATE_RESULT (decl), false))
- gcc_checking_assert ((*eslot)->get_entity_kind () == EK_REDIRECT
- && !(*eslot)->deps.length ());
- }
+ if (CHECKING_P && TREE_CODE (decl) == TEMPLATE_DECL)
+ /* The template_result should otherwise not be in the
+ table, or be an empty redirect (created above). */
+ if (auto *eslot = entity_slot (DECL_TEMPLATE_RESULT (decl), false))
+ gcc_checking_assert ((*eslot)->get_entity_kind () == EK_REDIRECT
+ && !(*eslot)->deps.length ());
if (ek != EK_USING)
{
@@ -13114,16 +13084,10 @@ specialization_add (bool decl_p, spec_entry *entry, void *data_)
heuristic. We don't attempt to replicate that algorithm, but
observe its behaviour and reproduce it upon read back. */
- gcc_checking_assert (DECL_ALIAS_TEMPLATE_P (entry->tmpl)
- || TREE_CODE (entry->spec) == ENUMERAL_TYPE
+ gcc_checking_assert (TREE_CODE (entry->spec) == ENUMERAL_TYPE
|| DECL_CLASS_TEMPLATE_P (entry->tmpl));
- /* Only alias templates can appear in both tables (and
- if they're in the type table they must also be in the decl
- table). */
- gcc_checking_assert
- (!match_mergeable_specialization (true, entry)
- == !DECL_ALIAS_TEMPLATE_P (entry->tmpl));
+ gcc_checking_assert (!match_mergeable_specialization (true, entry));
}
else if (VAR_OR_FUNCTION_DECL_P (entry->spec))
gcc_checking_assert (!DECL_LOCAL_DECL_P (entry->spec));
@@ -13179,7 +13143,6 @@ depset::hash::add_specializations (bool decl_p)
spec_entry *entry = data.pop ();
tree spec = entry->spec;
int use_tpl = 0;
- bool is_alias = false;
bool is_friend = false;
if (decl_p && DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P (entry->tmpl))
@@ -13187,13 +13150,7 @@ depset::hash::add_specializations (bool decl_p)
instantiation. */
is_friend = true;
- if (!decl_p && DECL_ALIAS_TEMPLATE_P (entry->tmpl))
- {
- spec = TYPE_NAME (spec);
- is_alias = true;
- }
-
- if (decl_p || is_alias)
+ if (decl_p)
{
if (tree ti = DECL_TEMPLATE_INFO (spec))
{
@@ -13278,20 +13235,9 @@ depset::hash::add_specializations (bool decl_p)
gcc_checking_assert (!TREE_VISITED (spec));
depset *dep = make_dependency (spec, depset::EK_SPECIALIZATION);
if (dep->is_special ())
- {
- /* An already located specialization, this must be the TYPE
- corresponding to an alias_decl we found in the decl
- table. */
- spec_entry *other = reinterpret_cast <spec_entry *> (dep->deps[0]);
- gcc_checking_assert (!decl_p && is_alias && !dep->is_type_spec ());
- gcc_checking_assert (other->tmpl == entry->tmpl
- && template_args_equal (other->args, entry->args)
- && TREE_TYPE (other->spec) == entry->spec);
- dep->set_flag_bit<DB_ALIAS_SPEC_BIT> ();
- }
+ gcc_unreachable ();
else
{
- gcc_checking_assert (decl_p || !is_alias);
if (dep->get_entity_kind () == depset::EK_REDIRECT)
dep = dep->deps[0];
else if (dep->get_entity_kind () == depset::EK_SPECIALIZATION)
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index 040ced45187..514e8029d03 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -10055,6 +10055,32 @@ lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
/* Now we should have enough arguments. */
gcc_assert (parm_depth == arg_depth);
+ if (DECL_ALIAS_TEMPLATE_P (gen_tmpl))
+ {
+ /* The user referred to a specialization of an alias
+ template represented by GEN_TMPL.
+
+ [temp.alias]/2 says:
+
+ When a template-id refers to the specialization of an
+ alias template, it is equivalent to the associated
+ type obtained by substitution of its
+ template-arguments for the template-parameters in the
+ type-id of the alias template. */
+
+ t = instantiate_alias_template (gen_tmpl, arglist, complain);
+ /* Note that the call above (by indirectly calling
+ register_specialization in tsubst_decl) registers the
+ TYPE_DECL representing the specialization of the alias
+ template. So next time someone substitutes ARGLIST for
+ the template parms into the alias template (GEN_TMPL),
+ she'll get that TYPE_DECL back. */
+
+ if (t == error_mark_node)
+ return error_mark_node;
+ return TREE_TYPE (t);
+ }
+
/* From here on, we're only interested in the most general
template. */
@@ -10120,7 +10146,6 @@ lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
lookup. This prevents redundant checks on previously
instantiated specializations. */
if (flag_concepts
- && !DECL_ALIAS_TEMPLATE_P (gen_tmpl)
&& !constraints_satisfied_p (gen_tmpl, arglist))
{
if (complain & tf_error)
@@ -10189,31 +10214,7 @@ lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
context = global_namespace;
/* Create the type. */
- if (DECL_ALIAS_TEMPLATE_P (gen_tmpl))
- {
- /* The user referred to a specialization of an alias
- template represented by GEN_TMPL.
-
- [temp.alias]/2 says:
-
- When a template-id refers to the specialization of an
- alias template, it is equivalent to the associated
- type obtained by substitution of its
- template-arguments for the template-parameters in the
- type-id of the alias template. */
-
- t = tsubst (TREE_TYPE (gen_tmpl), arglist, complain, in_decl);
- /* Note that the call above (by indirectly calling
- register_specialization in tsubst_decl) registers the
- TYPE_DECL representing the specialization of the alias
- template. So next time someone substitutes ARGLIST for
- the template parms into the alias template (GEN_TMPL),
- she'll get that TYPE_DECL back. */
-
- if (t == error_mark_node)
- return t;
- }
- else if (TREE_CODE (template_type) == ENUMERAL_TYPE)
+ if (TREE_CODE (template_type) == ENUMERAL_TYPE)
{
if (!is_dependent_type)
{
@@ -10301,8 +10302,7 @@ lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
}
}
- if (OVERLOAD_TYPE_P (t)
- && !DECL_ALIAS_TEMPLATE_P (gen_tmpl))
+ if (OVERLOAD_TYPE_P (t))
{
static const char *tags[] = {"abi_tag", "may_alias"};
@@ -10369,7 +10369,7 @@ lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
{
TREE_VEC_LENGTH (arglist)--;
++processing_template_decl;
- tree tinfo = TYPE_TEMPLATE_INFO_MAYBE_ALIAS (TREE_TYPE (gen_tmpl));
+ tree tinfo = TYPE_TEMPLATE_INFO (TREE_TYPE (gen_tmpl));
tree partial_inst_args =
tsubst (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo)),
arglist, complain, NULL_TREE);
@@ -10407,17 +10407,9 @@ lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
TEMPLATE_PARM_LEVEL. */
found = tsubst (gen_tmpl, arglist, tf_none, NULL_TREE);
TREE_VEC_LENGTH (arglist)++;
- /* FOUND is either a proper class type, or an alias
- template specialization. In the later case, it's a
- TYPE_DECL, resulting from the substituting of arguments
- for parameters in the TYPE_DECL of the alias template
- done earlier. So be careful while getting the template
- of FOUND. */
found = (TREE_CODE (found) == TEMPLATE_DECL
? found
- : (TREE_CODE (found) == TYPE_DECL
- ? DECL_TI_TEMPLATE (found)
- : CLASSTYPE_TI_TEMPLATE (found)));
+ : CLASSTYPE_TI_TEMPLATE (found));
if (DECL_CLASS_TEMPLATE_P (found)
&& CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (found)))
@@ -10447,8 +10439,7 @@ lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
DECL_TEMPLATE_INSTANTIATIONS (found));
if (TREE_CODE (template_type) == ENUMERAL_TYPE
- && !uses_template_parms (current_nonlambda_scope ())
- && !DECL_ALIAS_TEMPLATE_P (gen_tmpl))
+ && !uses_template_parms (current_nonlambda_scope ()))
/* Now that the type has been registered on the instantiations
list, we set up the enumerators. Because the enumeration
constants may involve the enumeration type itself, we make
@@ -31578,8 +31569,8 @@ get_mergeable_specialization_flags (tree tmpl, tree decl)
get_mergeable_specialization_flags. */
void
-add_mergeable_specialization (bool decl_p, bool alias_p, spec_entry *elt,
- tree decl, unsigned flags)
+add_mergeable_specialization (bool decl_p, spec_entry *elt, tree decl,
+ unsigned flags)
{
hashval_t hash = spec_hasher::hash (elt);
if (decl_p)
@@ -31590,15 +31581,8 @@ add_mergeable_specialization (bool decl_p, bool alias_p, spec_entry *elt,
auto entry = ggc_alloc<spec_entry> ();
*entry = *elt;
*slot = entry;
-
- if (alias_p)
- {
- elt->spec = TREE_TYPE (elt->spec);
- gcc_checking_assert (elt->spec);
- }
}
-
- if (!decl_p || alias_p)
+ else
{
auto *slot = type_specializations->find_slot_with_hash (elt, hash, INSERT);
diff --git a/gcc/testsuite/g++.dg/modules/pr99425-1_b.H b/gcc/testsuite/g++.dg/modules/pr99425-1_b.H
index 53d28b4ef5e..e75b3129dd3 100644
--- a/gcc/testsuite/g++.dg/modules/pr99425-1_b.H
+++ b/gcc/testsuite/g++.dg/modules/pr99425-1_b.H
@@ -15,5 +15,5 @@ inline void widget (Cont parm)
ssize (parm);
}
-// { dg-final { scan-lang-dump {Read:-[0-9]*'s alias spec merge key \(new\) type_decl:'::make_signed_t'\n ... Read:-[0-9]*'s type spec merge key \(new\) type_decl:'::make_signed'\n Read:-[0-9]*'s named merge key \(matched\) template_decl:'::template ssize'} module } }
+// { dg-final { scan-lang-dump {Read:-[0-9]*'s decl spec merge key \(new\) type_decl:'::make_signed_t'\n ... Read:-[0-9]*'s type spec merge key \(new\) type_decl:'::make_signed'\n Read:-[0-9]*'s named merge key \(matched\) template_decl:'::template ssize'} module } }
diff --git a/gcc/testsuite/g++.dg/modules/tpl-alias-1_a.H b/gcc/testsuite/g++.dg/modules/tpl-alias-1_a.H
index 37002ee9ae1..14a25be586f 100644
--- a/gcc/testsuite/g++.dg/modules/tpl-alias-1_a.H
+++ b/gcc/testsuite/g++.dg/modules/tpl-alias-1_a.H
@@ -6,4 +6,4 @@
// { dg-final { scan-lang-dump {Writing decl tmpl spec:-[0-9]* template_decl:'::allocator_traits<::allocator<long int>>::template rebind_alloc<_Up>'} module } }
// { dg-final { scan-lang-dump {Writing decl tmpl spec:-[0-9]* type_decl:'::allocator_traits<::allocator<long int>>::template rebind_alloc<_Up>'} module } }
-// { dg-final { scan-lang-dump {Writing:-[0-9]*'s alias spec merge key \(specialization\) type_decl:'::allocator_traits<::allocator<long int>>::rebind_alloc<long int>'} module } }
+// { dg-final { scan-lang-dump {Writing:-[0-9]*'s decl spec merge key \(specialization\) type_decl:'::allocator_traits<::allocator<long int>>::rebind_alloc<long int>'} module } }
diff --git a/gcc/testsuite/g++.dg/modules/tpl-alias-2_a.H b/gcc/testsuite/g++.dg/modules/tpl-alias-2_a.H
new file mode 100644
index 00000000000..76917f778e0
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/tpl-alias-2_a.H
@@ -0,0 +1,15 @@
+// PR c++/103994
+// { dg-additional-options -fmodule-header }
+// { dg-module-cmi {} }
+
+template<class>
+struct A {
+ template<class> using key_arg = int;
+};
+
+struct B {
+ template<class T>
+ void f() {
+ using type = A<B>::key_arg<T>;
+ }
+};
diff --git a/gcc/testsuite/g++.dg/modules/tpl-alias-2_b.C b/gcc/testsuite/g++.dg/modules/tpl-alias-2_b.C
new file mode 100644
index 00000000000..44fa5f42757
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/tpl-alias-2_b.C
@@ -0,0 +1,9 @@
+// PR c++/103994
+// { dg-additional-options -fmodules-ts }
+
+import "tpl-alias-2_a.H";
+
+int main() {
+ B b;
+ b.f<int>();
+}
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2024-03-07 21:39 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-03-07 21:39 [gcc r14-9374] c++/modules: member alias tmpl partial inst [PR103994] Patrick Palka
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).