Re: [PATCH] c++: improve a couple of TMPL_ARGS_* accessor macros
On Thu, 12 May 2022, Jason Merrill wrote:
> On 5/12/22 14:14, Patrick Palka wrote:
> > On Thu, 12 May 2022, Patrick Palka wrote:
> >
> > > After r13-332-g88459c3965e2a2, it looks like we can safely remove the
> > > NULL test from TMPL_ARGS_HAVE_MULTIPLE_LEVELS, which simplifies its
> > > semantics.
> > >
> > > And TMPL_ARGS_LEVEL should verify the level argument is sane in the
> > > one-dimensional vector case. This change uncovered a couple of latent
> > > bugs: in try_class_unification, we weren't correctly copying
> > > multidimensional targs, and in unify_pack_expansion it seems an
> > > inequality test needs to be reversed (not sure about this latter fix,
> > > the test was added in r8-6178-g2625472ffa519e FWIW).
> > >
> > > Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
> > > trunk? Also tested on cmcstl2 and range-v3.
> > >
> > > gcc/cp/ChangeLog:
> > >
> > > * cp-tree.h (TMPL_ARGS_HAVE_MULTIPLE_LEVELS): Remove NULL test.
> > > (TMPL_ARGS_LEVEL): Assert LEVEL is 1 when
> > > TMPL_ARGS_HAVE_MULTIPLE_LEVELS is false.
> > > * pt.cc (try_class_unification): Correctly copy multidimensional
> > > targs.
> > > (unify_pack_expansion): Fix level comparison.
> > > ---
> > > gcc/cp/cp-tree.h | 5 +++--
> > > gcc/cp/pt.cc | 12 ++--
> > > 2 files changed, 9 insertions(+), 8 deletions(-)
> > >
> > > diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
> > > index b6961a796af..f681d32ac93 100644
> > > --- a/gcc/cp/cp-tree.h
> > > +++ b/gcc/cp/cp-tree.h
> > > @@ -3766,7 +3766,7 @@ struct GTY(()) lang_decl {
> > > /* Nonzero if the template arguments is actually a vector of vectors,
> > > rather than just a vector. */
> > > #define TMPL_ARGS_HAVE_MULTIPLE_LEVELS(NODE) \
> > > - (NODE && TREE_VEC_LENGTH (NODE) && TREE_VEC_ELT (NODE, 0) \
> > > + (TREE_VEC_LENGTH (NODE) && TREE_VEC_ELT (NODE, 0) \
> > > && TREE_CODE (TREE_VEC_ELT (NODE, 0)) == TREE_VEC)
> > > /* The depth of a template argument vector. When called directly by
> > > @@ -3783,7 +3783,8 @@ struct GTY(()) lang_decl {
> > > args is level 1, not level 0. */
> > > #define TMPL_ARGS_LEVEL(ARGS, LEVEL)\
> > > (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (ARGS)\
> > > - ? TREE_VEC_ELT (ARGS, (LEVEL) - 1) : (ARGS))
> > > + ? TREE_VEC_ELT (ARGS, (LEVEL) - 1)\
> > > + : (gcc_checking_assert (LEVEL == 1), (ARGS)))
> > > /* Set the LEVELth level of the template ARGS to VAL. This macro does
> > > not work with single-level argument vectors. */
> > > diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
> > > index 2c7c5f8bb5d..75b21e5c88a 100644
> > > --- a/gcc/cp/pt.cc
> > > +++ b/gcc/cp/pt.cc
> > > @@ -23398,8 +23398,6 @@ static tree
> > > try_class_unification (tree tparms, tree targs, tree parm, tree arg,
> > > bool explain_p)
> > > {
> > > - tree copy_of_targs;
> > > -
> > > if (!CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
> > > return NULL_TREE;
> > > else if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
> > > @@ -23438,17 +23436,19 @@ try_class_unification (tree tparms, tree targs,
> > > tree parm, tree arg,
> > >because there are two ways to unify base classes of S<0, 1, 2>
> > >with S. If we kept the already deduced knowledge, we
> > >would reject the possibility I=1. */
> > > - copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
> > > + targs = copy_template_args (targs);
> > > + for (tree& targ : tree_vec_range (INNERMOST_TEMPLATE_ARGS (targs)))
> > > +targ = NULL_TREE;
> >
> > It occurred to me that we don't need to make a copy of (the TREE_VECs
> > for) the outer template arguments, so it might be better to use
> > copy_node manually instead of copy_template_args. But this redundant
> > copying shouldn't matter much if we make sure to ggc_free it afterwards.
> > So here's v2 which additionally makes try_class_unification ggc_free
> > this copy of targs (bootstrap and regtest in progress):
> >
> > -- >8 --
> >
> > Subject: [PATCH] c++: improve a couple of TMPL_ARGS_* accessor macros
> >
> > After r13-332-g88459c3965e2a2, it looks like we can safely remove the
>
Re: [PATCH] c++: improve a couple of TMPL_ARGS_* accessor macros
On 5/12/22 14:14, Patrick Palka wrote:
On Thu, 12 May 2022, Patrick Palka wrote:
After r13-332-g88459c3965e2a2, it looks like we can safely remove the
NULL test from TMPL_ARGS_HAVE_MULTIPLE_LEVELS, which simplifies its
semantics.
And TMPL_ARGS_LEVEL should verify the level argument is sane in the
one-dimensional vector case. This change uncovered a couple of latent
bugs: in try_class_unification, we weren't correctly copying
multidimensional targs, and in unify_pack_expansion it seems an
inequality test needs to be reversed (not sure about this latter fix,
the test was added in r8-6178-g2625472ffa519e FWIW).
Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
trunk? Also tested on cmcstl2 and range-v3.
gcc/cp/ChangeLog:
* cp-tree.h (TMPL_ARGS_HAVE_MULTIPLE_LEVELS): Remove NULL test.
(TMPL_ARGS_LEVEL): Assert LEVEL is 1 when
TMPL_ARGS_HAVE_MULTIPLE_LEVELS is false.
* pt.cc (try_class_unification): Correctly copy multidimensional
targs.
(unify_pack_expansion): Fix level comparison.
---
gcc/cp/cp-tree.h | 5 +++--
gcc/cp/pt.cc | 12 ++--
2 files changed, 9 insertions(+), 8 deletions(-)
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index b6961a796af..f681d32ac93 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -3766,7 +3766,7 @@ struct GTY(()) lang_decl {
/* Nonzero if the template arguments is actually a vector of vectors,
rather than just a vector. */
#define TMPL_ARGS_HAVE_MULTIPLE_LEVELS(NODE) \
- (NODE && TREE_VEC_LENGTH (NODE) && TREE_VEC_ELT (NODE, 0) \
+ (TREE_VEC_LENGTH (NODE) && TREE_VEC_ELT (NODE, 0) \
&& TREE_CODE (TREE_VEC_ELT (NODE, 0)) == TREE_VEC)
/* The depth of a template argument vector. When called directly by
@@ -3783,7 +3783,8 @@ struct GTY(()) lang_decl {
args is level 1, not level 0. */
#define TMPL_ARGS_LEVEL(ARGS, LEVEL) \
(TMPL_ARGS_HAVE_MULTIPLE_LEVELS (ARGS) \
- ? TREE_VEC_ELT (ARGS, (LEVEL) - 1) : (ARGS))
+ ? TREE_VEC_ELT (ARGS, (LEVEL) - 1) \
+ : (gcc_checking_assert (LEVEL == 1), (ARGS)))
/* Set the LEVELth level of the template ARGS to VAL. This macro does
not work with single-level argument vectors. */
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index 2c7c5f8bb5d..75b21e5c88a 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -23398,8 +23398,6 @@ static tree
try_class_unification (tree tparms, tree targs, tree parm, tree arg,
bool explain_p)
{
- tree copy_of_targs;
-
if (!CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
return NULL_TREE;
else if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
@@ -23438,17 +23436,19 @@ try_class_unification (tree tparms, tree targs, tree
parm, tree arg,
because there are two ways to unify base classes of S<0, 1, 2>
with S. If we kept the already deduced knowledge, we
would reject the possibility I=1. */
- copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
+ targs = copy_template_args (targs);
+ for (tree& targ : tree_vec_range (INNERMOST_TEMPLATE_ARGS (targs)))
+targ = NULL_TREE;
It occurred to me that we don't need to make a copy of (the TREE_VECs
for) the outer template arguments, so it might be better to use
copy_node manually instead of copy_template_args. But this redundant
copying shouldn't matter much if we make sure to ggc_free it afterwards.
So here's v2 which additionally makes try_class_unification ggc_free
this copy of targs (bootstrap and regtest in progress):
-- >8 --
Subject: [PATCH] c++: improve a couple of TMPL_ARGS_* accessor macros
After r13-332-g88459c3965e2a2, it looks like we can safely remove the
NULL test from TMPL_ARGS_HAVE_MULTIPLE_LEVELS, which should make its
uses easier to reason about.
because we should have given up before trying to check that?
And TMPL_ARGS_LEVEL should verify the level argument is valid in the
one-dimensional vector case. This change uncovered a couple of latent
issues: in try_class_unification, we weren't correctly copying
multidimensional targs, and in unify_pack_expansion it seems an
inequality test needs to be reversed. This patch fixes both these
issues, and in passing makes the former function ggc_free the copy of
targs.
OK.
gcc/cp/ChangeLog:
* cp-tree.h (TMPL_ARGS_HAVE_MULTIPLE_LEVELS): Remove NULL test.
(TMPL_ARGS_LEVEL): Assert LEVEL is 1 when
TMPL_ARGS_HAVE_MULTIPLE_LEVELS is false.
* pt.cc (try_class_unification): Correctly copy multidimensional
targs. Free the copy of targs.
(unify_pack_expansion): Fix level comparison.
---
gcc/cp/cp-tree.h | 5 +++--
gcc/cp/pt.cc | 28 ++--
2 files changed, 17 insertions(+), 16 deletions(-)
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index b6961a796af..c28a3311dde 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@
Re: [PATCH] c++: improve a couple of TMPL_ARGS_* accessor macros
On Thu, 12 May 2022, Patrick Palka wrote:
> After r13-332-g88459c3965e2a2, it looks like we can safely remove the
> NULL test from TMPL_ARGS_HAVE_MULTIPLE_LEVELS, which simplifies its
> semantics.
>
> And TMPL_ARGS_LEVEL should verify the level argument is sane in the
> one-dimensional vector case. This change uncovered a couple of latent
> bugs: in try_class_unification, we weren't correctly copying
> multidimensional targs, and in unify_pack_expansion it seems an
> inequality test needs to be reversed (not sure about this latter fix,
> the test was added in r8-6178-g2625472ffa519e FWIW).
>
> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
> trunk? Also tested on cmcstl2 and range-v3.
>
> gcc/cp/ChangeLog:
>
> * cp-tree.h (TMPL_ARGS_HAVE_MULTIPLE_LEVELS): Remove NULL test.
> (TMPL_ARGS_LEVEL): Assert LEVEL is 1 when
> TMPL_ARGS_HAVE_MULTIPLE_LEVELS is false.
> * pt.cc (try_class_unification): Correctly copy multidimensional
> targs.
> (unify_pack_expansion): Fix level comparison.
> ---
> gcc/cp/cp-tree.h | 5 +++--
> gcc/cp/pt.cc | 12 ++--
> 2 files changed, 9 insertions(+), 8 deletions(-)
>
> diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
> index b6961a796af..f681d32ac93 100644
> --- a/gcc/cp/cp-tree.h
> +++ b/gcc/cp/cp-tree.h
> @@ -3766,7 +3766,7 @@ struct GTY(()) lang_decl {
> /* Nonzero if the template arguments is actually a vector of vectors,
> rather than just a vector. */
> #define TMPL_ARGS_HAVE_MULTIPLE_LEVELS(NODE) \
> - (NODE && TREE_VEC_LENGTH (NODE) && TREE_VEC_ELT (NODE, 0) \
> + (TREE_VEC_LENGTH (NODE) && TREE_VEC_ELT (NODE, 0) \
> && TREE_CODE (TREE_VEC_ELT (NODE, 0)) == TREE_VEC)
>
> /* The depth of a template argument vector. When called directly by
> @@ -3783,7 +3783,8 @@ struct GTY(()) lang_decl {
> args is level 1, not level 0. */
> #define TMPL_ARGS_LEVEL(ARGS, LEVEL) \
>(TMPL_ARGS_HAVE_MULTIPLE_LEVELS (ARGS) \
> - ? TREE_VEC_ELT (ARGS, (LEVEL) - 1) : (ARGS))
> + ? TREE_VEC_ELT (ARGS, (LEVEL) - 1)\
> + : (gcc_checking_assert (LEVEL == 1), (ARGS)))
>
> /* Set the LEVELth level of the template ARGS to VAL. This macro does
> not work with single-level argument vectors. */
> diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
> index 2c7c5f8bb5d..75b21e5c88a 100644
> --- a/gcc/cp/pt.cc
> +++ b/gcc/cp/pt.cc
> @@ -23398,8 +23398,6 @@ static tree
> try_class_unification (tree tparms, tree targs, tree parm, tree arg,
> bool explain_p)
> {
> - tree copy_of_targs;
> -
>if (!CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
> return NULL_TREE;
>else if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
> @@ -23438,17 +23436,19 @@ try_class_unification (tree tparms, tree targs,
> tree parm, tree arg,
> because there are two ways to unify base classes of S<0, 1, 2>
> with S. If we kept the already deduced knowledge, we
> would reject the possibility I=1. */
> - copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
> + targs = copy_template_args (targs);
> + for (tree& targ : tree_vec_range (INNERMOST_TEMPLATE_ARGS (targs)))
> +targ = NULL_TREE;
It occurred to me that we don't need to make a copy of (the TREE_VECs
for) the outer template arguments, so it might be better to use
copy_node manually instead of copy_template_args. But this redundant
copying shouldn't matter much if we make sure to ggc_free it afterwards.
So here's v2 which additionally makes try_class_unification ggc_free
this copy of targs (bootstrap and regtest in progress):
-- >8 --
Subject: [PATCH] c++: improve a couple of TMPL_ARGS_* accessor macros
After r13-332-g88459c3965e2a2, it looks like we can safely remove the
NULL test from TMPL_ARGS_HAVE_MULTIPLE_LEVELS, which should make its
uses easier to reason about.
And TMPL_ARGS_LEVEL should verify the level argument is valid in the
one-dimensional vector case. This change uncovered a couple of latent
issues: in try_class_unification, we weren't correctly copying
multidimensional targs, and in unify_pack_expansion it seems an
inequality test needs to be reversed. This patch fixes both these
issues, and in passing makes the former function ggc_free the copy of
targs.
gcc/cp/ChangeLog:
* cp-tree.h (TMPL_ARGS_HAVE_MULTIPLE_LEVELS): Remove NULL test.
(TMPL_ARGS_LEVEL): Assert LEVEL is 1 when
TMPL_ARGS_HAVE_MULTIPLE_LEVELS is false.
* pt.cc (try_class_unification): Correctly copy multidimensional
targs. Free the copy of targs.
(unify_pack_expansion): Fix level comparison.
---
gcc/cp/cp-tree.h | 5 +++--
gcc/cp/pt.cc | 28 ++
[PATCH] c++: improve a couple of TMPL_ARGS_* accessor macros
After r13-332-g88459c3965e2a2, it looks like we can safely remove the
NULL test from TMPL_ARGS_HAVE_MULTIPLE_LEVELS, which simplifies its
semantics.
And TMPL_ARGS_LEVEL should verify the level argument is sane in the
one-dimensional vector case. This change uncovered a couple of latent
bugs: in try_class_unification, we weren't correctly copying
multidimensional targs, and in unify_pack_expansion it seems an
inequality test needs to be reversed (not sure about this latter fix,
the test was added in r8-6178-g2625472ffa519e FWIW).
Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
trunk? Also tested on cmcstl2 and range-v3.
gcc/cp/ChangeLog:
* cp-tree.h (TMPL_ARGS_HAVE_MULTIPLE_LEVELS): Remove NULL test.
(TMPL_ARGS_LEVEL): Assert LEVEL is 1 when
TMPL_ARGS_HAVE_MULTIPLE_LEVELS is false.
* pt.cc (try_class_unification): Correctly copy multidimensional
targs.
(unify_pack_expansion): Fix level comparison.
---
gcc/cp/cp-tree.h | 5 +++--
gcc/cp/pt.cc | 12 ++--
2 files changed, 9 insertions(+), 8 deletions(-)
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index b6961a796af..f681d32ac93 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -3766,7 +3766,7 @@ struct GTY(()) lang_decl {
/* Nonzero if the template arguments is actually a vector of vectors,
rather than just a vector. */
#define TMPL_ARGS_HAVE_MULTIPLE_LEVELS(NODE)\
- (NODE && TREE_VEC_LENGTH (NODE) && TREE_VEC_ELT (NODE, 0) \
+ (TREE_VEC_LENGTH (NODE) && TREE_VEC_ELT (NODE, 0) \
&& TREE_CODE (TREE_VEC_ELT (NODE, 0)) == TREE_VEC)
/* The depth of a template argument vector. When called directly by
@@ -3783,7 +3783,8 @@ struct GTY(()) lang_decl {
args is level 1, not level 0. */
#define TMPL_ARGS_LEVEL(ARGS, LEVEL) \
(TMPL_ARGS_HAVE_MULTIPLE_LEVELS (ARGS) \
- ? TREE_VEC_ELT (ARGS, (LEVEL) - 1) : (ARGS))
+ ? TREE_VEC_ELT (ARGS, (LEVEL) - 1) \
+ : (gcc_checking_assert (LEVEL == 1), (ARGS)))
/* Set the LEVELth level of the template ARGS to VAL. This macro does
not work with single-level argument vectors. */
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index 2c7c5f8bb5d..75b21e5c88a 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -23398,8 +23398,6 @@ static tree
try_class_unification (tree tparms, tree targs, tree parm, tree arg,
bool explain_p)
{
- tree copy_of_targs;
-
if (!CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
return NULL_TREE;
else if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
@@ -23438,17 +23436,19 @@ try_class_unification (tree tparms, tree targs, tree
parm, tree arg,
because there are two ways to unify base classes of S<0, 1, 2>
with S. If we kept the already deduced knowledge, we
would reject the possibility I=1. */
- copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
+ targs = copy_template_args (targs);
+ for (tree& targ : tree_vec_range (INNERMOST_TEMPLATE_ARGS (targs)))
+targ = NULL_TREE;
if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
{
- if (unify_bound_ttp_args (tparms, copy_of_targs, parm, arg, explain_p))
+ if (unify_bound_ttp_args (tparms, targs, parm, arg, explain_p))
return NULL_TREE;
return arg;
}
/* If unification failed, we're done. */
- if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
+ if (unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE, explain_p))
return NULL_TREE;
@@ -23649,7 +23649,7 @@ unify_pack_expansion (tree tparms, tree targs, tree
packed_parms,
/* Determine the index and level of this parameter pack. */
template_parm_level_and_index (parm_pack, , );
- if (level < levels)
+ if (level > levels)
continue;
/* Keep track of the parameter packs and their corresponding
--
2.36.1.63.gef9b086d95
