c++: Introduce append_ctor_to_tree_vector

On Mon, Jan 20, 2025 at 05:14:33PM -0500, Jason Merrill wrote:
> > --- gcc/cp/call.cc.jj       2025-01-15 18:24:36.135503866 +0100
> > +++ gcc/cp/call.cc  2025-01-17 14:42:38.201643385 +0100
> > @@ -4258,11 +4258,30 @@ add_list_candidates (tree fns, tree firs
> >     /* Expand the CONSTRUCTOR into a new argument vec.  */
>
> Maybe we could factor out a function called something like
> append_ctor_to_tree_vector from the common code between this and
> make_tree_vector_from_ctor?
>
> But this is OK as is if you don't want to pursue that.

I had the previous patch already tested and wanted to avoid delaying
the large initializer speedup re-reversion any further, so I've committed
the patch as is.

Here is an incremental patch to factor that out.

2025-01-22  Jakub Jelinek  <jakub@redhat.com>

gcc/c-family/
	* c-common.h (append_ctor_to_tree_vector): Declare.
	* c-common.cc (append_ctor_to_tree_vector): New function.
	(make_tree_vector_from_ctor): Use it.
gcc/cp/
	* call.cc (add_list_candidates): Use append_ctor_to_tree_vector.

3 files changed, 25 insertions, 34 deletions

diff --git a/gcc/c-family/c-common.cc b/gcc/c-family/c-common.cc
index 91d9072..c193eb2c 100644
--- a/gcc/c-family/c-common.cc
+++ b/gcc/c-family/c-common.cc
@@ -9010,33 +9010,42 @@ make_tree_vector_from_list (tree list)
   return ret;
 }
 
-/* Get a new tree vector of the values of a CONSTRUCTOR.  */
+/* Append to a tree vector V the values of a CONSTRUCTOR CTOR
+   and return the new possibly reallocated vector.  */
 
 vec<tree, va_gc> *
-make_tree_vector_from_ctor (tree ctor)
+append_ctor_to_tree_vector (vec<tree, va_gc> *v, tree ctor)
 {
-  vec<tree,va_gc> *ret = make_tree_vector ();
-  unsigned nelts = CONSTRUCTOR_NELTS (ctor);
-  vec_safe_reserve (ret, CONSTRUCTOR_NELTS (ctor));
+  unsigned nelts = vec_safe_length (v) + CONSTRUCTOR_NELTS (ctor);
+  vec_safe_reserve (v, CONSTRUCTOR_NELTS (ctor));
   for (unsigned i = 0; i < CONSTRUCTOR_NELTS (ctor); ++i)
     if (TREE_CODE (CONSTRUCTOR_ELT (ctor, i)->value) == RAW_DATA_CST)
       {
 	tree raw_data = CONSTRUCTOR_ELT (ctor, i)->value;
 	nelts += RAW_DATA_LENGTH (raw_data) - 1;
-	vec_safe_reserve (ret, nelts - ret->length ());
+	vec_safe_reserve (v, nelts - v->length ());
 	if (TYPE_PRECISION (TREE_TYPE (raw_data)) > CHAR_BIT
 	    || TYPE_UNSIGNED (TREE_TYPE (raw_data)))
 	  for (unsigned j = 0; j < (unsigned) RAW_DATA_LENGTH (raw_data); ++j)
-	    ret->quick_push (build_int_cst (TREE_TYPE (raw_data),
-					    RAW_DATA_UCHAR_ELT (raw_data, j)));
+	    v->quick_push (build_int_cst (TREE_TYPE (raw_data),
+					  RAW_DATA_UCHAR_ELT (raw_data, j)));
 	else
 	  for (unsigned j = 0; j < (unsigned) RAW_DATA_LENGTH (raw_data); ++j)
-	    ret->quick_push (build_int_cst (TREE_TYPE (raw_data),
-					    RAW_DATA_SCHAR_ELT (raw_data, j)));
+	    v->quick_push (build_int_cst (TREE_TYPE (raw_data),
+					  RAW_DATA_SCHAR_ELT (raw_data, j)));
       }
     else
-      ret->quick_push (CONSTRUCTOR_ELT (ctor, i)->value);
-  return ret;
+      v->quick_push (CONSTRUCTOR_ELT (ctor, i)->value);
+  return v;
+}
+
+/* Get a new tree vector of the values of a CONSTRUCTOR.  */
+
+vec<tree, va_gc> *
+make_tree_vector_from_ctor (tree ctor)
+{
+  vec<tree,va_gc> *ret = make_tree_vector ();
+  return append_ctor_to_tree_vector (ret, ctor);
 }
 
 /* Get a new tree vector which is a copy of an existing one.  */
diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h
index 94b1d2d..c5eb11d 100644
--- a/gcc/c-family/c-common.h
+++ b/gcc/c-family/c-common.h
@@ -1190,6 +1190,8 @@ extern vec<tree, va_gc> *make_tree_vector (void);
 extern void release_tree_vector (vec<tree, va_gc> *);
 extern vec<tree, va_gc> *make_tree_vector_single (tree);
 extern vec<tree, va_gc> *make_tree_vector_from_list (tree);
+extern vec<tree, va_gc> *append_ctor_to_tree_vector (vec<tree, va_gc> *,
+						     tree);
 extern vec<tree, va_gc> *make_tree_vector_from_ctor (tree);
 extern vec<tree, va_gc> *make_tree_vector_copy (const vec<tree, va_gc> *);
 
diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc
index 80015df..469af83 100644
--- a/gcc/cp/call.cc
+++ b/gcc/cp/call.cc
@@ -4258,30 +4258,10 @@ add_list_candidates (tree fns, tree first_arg,
 
   /* Expand the CONSTRUCTOR into a new argument vec.  */
   vec<tree, va_gc> *new_args;
-  unsigned nelts = nart + CONSTRUCTOR_NELTS (init_list);
-  vec_alloc (new_args, nelts);
+  vec_alloc (new_args, nart + CONSTRUCTOR_NELTS (init_list));
   for (unsigned i = 0; i < nart; ++i)
     new_args->quick_push ((*args)[i]);
-  for (unsigned i = 0; i < CONSTRUCTOR_NELTS (init_list); ++i)
-    if (TREE_CODE (CONSTRUCTOR_ELT (init_list, i)->value) == RAW_DATA_CST)
-      {
-	tree raw_data = CONSTRUCTOR_ELT (init_list, i)->value;
-	nelts += RAW_DATA_LENGTH (raw_data) - 1;
-	vec_safe_reserve (new_args, nelts - new_args->length ());
-	if (TYPE_PRECISION (TREE_TYPE (raw_data)) > CHAR_BIT
-	    || TYPE_UNSIGNED (TREE_TYPE (raw_data)))
-	  for (unsigned j = 0; j < (unsigned) RAW_DATA_LENGTH (raw_data); ++j)
-	    new_args->quick_push (build_int_cst (TREE_TYPE (raw_data),
-						 RAW_DATA_UCHAR_ELT (raw_data,
-								     j)));
-	else
-	  for (unsigned j = 0; j < (unsigned) RAW_DATA_LENGTH (raw_data); ++j)
-	    new_args->quick_push (build_int_cst (TREE_TYPE (raw_data),
-						 RAW_DATA_SCHAR_ELT (raw_data,
-								     j)));
-      }
-    else
-      new_args->quick_push (CONSTRUCTOR_ELT (init_list, i)->value);
+  new_args = append_ctor_to_tree_vector (new_args, init_list);
 
   /* We aren't looking for list-ctors anymore.  */
   flags &= ~LOOKUP_LIST_ONLY;