scratch/hash-table-perf f3e985a16ba 14/37: Don't print or read the hash table size parameter

[Mattias Engdegård]

branch: scratch/hash-table-perf
commit f3e985a16ba52d6d12ba01ffa6cb3ca2b00dd240
Author: Mattias Engdegård <mattiase@acm.org>
Commit: Mattias Engdegård <mattiase@acm.org>

    Don't print or read the hash table size parameter
    
    It's not a meaningful part of the external representation.
    This allows for faster printing and reading, smaller
    external representation, and less memory consumption.
    
    * src/print.c (print_object): Omit size.
    * src/lread.c (hash_table_from_plist): Take size from the data.
---
 src/lread.c | 17 +++++++++--------
 src/print.c |  7 ++-----
 2 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/src/lread.c b/src/lread.c
index 255b6e914d9..a7ee0cb739c 100644
--- a/src/lread.c
+++ b/src/lread.c
@@ -3426,7 +3426,6 @@ hash_table_from_plist (Lisp_Object plist)
       }                                                        \
   } while (0)
 
-  ADDPARAM (size);
   ADDPARAM (test);
   ADDPARAM (weakness);
   ADDPARAM (rehash_size);
@@ -3434,23 +3433,25 @@ hash_table_from_plist (Lisp_Object plist)
   ADDPARAM (purecopy);
 
   Lisp_Object data = plist_get (plist, Qdata);
+  if (!(NILP (data) || CONSP (data)))
+    error ("Hash table data is not a list");
+  ptrdiff_t data_len = list_length (data);
+  if (data_len & 1)
+    error ("Hash table data length is odd");
+  *par++ = QCsize;
+  *par++ = make_fixnum (data_len / 2);
 
   /* Now use params to make a new hash table and fill it.  */
   Lisp_Object ht = Fmake_hash_table (par - params, params);
 
-  Lisp_Object last = data;
-  FOR_EACH_TAIL_SAFE (data)
+  while (!NILP (data))
     {
       Lisp_Object key = XCAR (data);
       data = XCDR (data);
-      if (!CONSP (data))
-       break;
       Lisp_Object val = XCAR (data);
-      last = XCDR (data);
       Fputhash (key, val, ht);
+      data = XCDR (data);
     }
-  if (!NILP (last))
-    error ("Hash table data is not a list of even length");
 
   return ht;
 }
diff --git a/src/print.c b/src/print.c
index 2da64c1d329..3c7e496bb51 100644
--- a/src/print.c
+++ b/src/print.c
@@ -2574,11 +2574,8 @@ print_object (Lisp_Object obj, Lisp_Object printcharfun, 
bool escapeflag)
          {
            struct Lisp_Hash_Table *h = XHASH_TABLE (obj);
            /* Implement a readable output, e.g.:
-              #s(hash-table size 2 test equal data (k1 v1 k2 v2)) */
-           /* Always print the size.  */
-           int len = sprintf (buf, "#s(hash-table size %"pD"d",
-                              HASH_TABLE_SIZE (h));
-           strout (buf, len, len, printcharfun);
+              #s(hash-table test equal data (k1 v1 k2 v2)) */
+           print_c_string ("#s(hash-table", printcharfun);
 
            if (!BASE_EQ (h->test.name, Qeql))
              {