[no subject]

[Gavin D. Smith]

branch: master
commit ff2b5d22ee2807e4f88d38d0ebc2ea41f496c98e
Author: Gavin Smith <gavinsmith0123@gmail.com>
AuthorDate: Thu Apr 13 11:44:13 2023 +0100

    * tp/Texinfo/XS/parsetexi/tree.c (spare_element, new_element)
    (destroy_element, reset_obstacks): Reuse storage from
    destroy_element, which is called a lot from abort_empty_line.
    * tp/Texinfo/XS/parsetexi/end_line.c (end_line): Disable
    check for infinite loop when closing commands.
---
 ChangeLog                          |  8 ++++++++
 tp/Texinfo/XS/parsetexi/end_line.c |  3 ++-
 tp/Texinfo/XS/parsetexi/tree.c     | 25 ++++++++++++++++++++++---
 3 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index d4b1ebf024..ef33a58083 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2023-04-13  Gavin Smith <gavinsmith0123@gmail.com>
+
+       * tp/Texinfo/XS/parsetexi/tree.c (spare_element, new_element)
+       (destroy_element, reset_obstacks): Reuse storage from
+       destroy_element, which is called a lot from abort_empty_line.
+       * tp/Texinfo/XS/parsetexi/end_line.c (end_line): Disable
+       check for infinite loop when closing commands.
+
 2023-04-12  Gavin Smith <gavinsmith0123@gmail.com>
 
        * tp/Texinfo/XS/parsetexi/tree_types.h (ELEMENT):
diff --git a/tp/Texinfo/XS/parsetexi/end_line.c 
b/tp/Texinfo/XS/parsetexi/end_line.c
index d40721c508..5ecef0d4bc 100644
--- a/tp/Texinfo/XS/parsetexi/end_line.c
+++ b/tp/Texinfo/XS/parsetexi/end_line.c
@@ -2016,7 +2016,8 @@ end_line (ELEMENT *current)
             }
         }
 
-      if (current == current_old)
+      /* Check is disabled as new_element can reuse storage. */
+      if (0 && current == current_old)
         fatal ("infinite loop when closing commands");
 
       current = end_line (current);
diff --git a/tp/Texinfo/XS/parsetexi/tree.c b/tp/Texinfo/XS/parsetexi/tree.c
index 2766409388..9aefea3d24 100644
--- a/tp/Texinfo/XS/parsetexi/tree.c
+++ b/tp/Texinfo/XS/parsetexi/tree.c
@@ -33,12 +33,19 @@ alloc_and_zero (size_t size)
   return calloc (1, size);
 }
 
+/* Used with destroy_element to reuse storage, e.g. from
+   abort_empty_line.  Reduces memory use slightly (about 5% from testing)
+   for large manuals. */
+static ELEMENT *spare_element;
+
 #define obstack_chunk_alloc alloc_and_zero
 #define obstack_chunk_free free
 
 void
 reset_obstacks (void)
 {
+  spare_element = 0;
+
   if (obs_element_first)
     obstack_free (&obs_element, obs_element_first);
 
@@ -54,10 +61,20 @@ static ELEMENT *alloc_element (void)
 ELEMENT *
 new_element (enum element_type type)
 {
-  ELEMENT *e = alloc_element ();
+  ELEMENT *e;
 
-  /* alloc_element zeroes *e.  We assume null pointers have bit representation
-     of all zeroes. */
+  if (spare_element)
+    {
+      e = spare_element;
+      spare_element = 0;
+      memset (e, 0, sizeof (ELEMENT));
+    }
+  else
+    {
+      e = alloc_element ();
+      /* alloc_element zeroes *e.  We assume null pointers have bit
+         representation of all zeroes. */
+    }
 
   e->type = type;
 
@@ -131,6 +148,8 @@ destroy_element (ELEMENT *e)
   destroy_associated_info (&e->extra_info);
   destroy_associated_info (&e->info_info);
 
+  spare_element = e;
+
   /* freed in reset_obstacks */
   /* free (e); */
 }