Tune pseudovector allocation assuming Qnil == 0

* alloc.c (allocate_pseudovector): Use memset for both
Lisp_Objects and regular slots.  Add zerolen arg.
* lisp.h (allocate_pseudovector): Adjust prototype.
(ALLOCATE_PSEUDOVECTOR): Adjust user.
(ALLOCATE_ZEROED_PSEUDOVECTOR): New macro.
(allocate_hash_table, allocate_window, allocate_frame)
(allocate_process, allocate_terminal): Remove prototypes.
* fns.c (allocate_hash_table): Now static here.
* frame.c (allocate_frame):
* process.c (allocate_process):
* terminal.c (allocate_terminal):
* window.c (allocate_window): Now static here.
Use ALLOCATE_ZEROED_PSEUDOVECTOR.  Add comment.

9 files changed, 89 insertions, 74 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index ae634f318f0..63da5cbd972 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,20 @@
+2015-01-16  Dmitry Antipov  <dmantipov@yandex.ru>
+
+        Tune pseudovector allocation assuming Qnil == 0.
+        * alloc.c (allocate_pseudovector): Use memset for both
+        Lisp_Objects and regular slots.  Add zerolen arg.
+        * lisp.h (allocate_pseudovector): Adjust prototype.
+        (ALLOCATE_PSEUDOVECTOR): Adjust user.
+        (ALLOCATE_ZEROED_PSEUDOVECTOR): New macro.
+        (allocate_hash_table, allocate_window, allocate_frame)
+        (allocate_process, allocate_terminal): Remove prototypes.
+        * fns.c (allocate_hash_table): Now static here.
+        * frame.c (allocate_frame):
+        * process.c (allocate_process):
+        * terminal.c (allocate_terminal):
+        * window.c (allocate_window): Now static here.
+        Use ALLOCATE_ZEROED_PSEUDOVECTOR.  Add comment.
+
 2015-01-16  Paul Eggert  <eggert@cs.ucla.edu>
 
         Give up on -Wsuggest-attribute=const
diff --git a/src/alloc.c b/src/alloc.c
index 7c937332407..22a15b4ac59 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -3163,19 +3163,19 @@ allocate_vector (EMACS_INT len)
 /* Allocate other vector-like structures.  */
 
 struct Lisp_Vector *
-allocate_pseudovector (int memlen, int lisplen, enum pvec_type tag)
+allocate_pseudovector (int memlen, int lisplen,
+                       int zerolen, enum pvec_type tag)
 {
   struct Lisp_Vector *v = allocate_vectorlike (memlen);
-  int i;
 
   /* Catch bogus values.  */
   eassert (tag <= PVEC_FONT);
   eassert (memlen - lisplen <= (1 << PSEUDOVECTOR_REST_BITS) - 1);
   eassert (lisplen <= (1 << PSEUDOVECTOR_SIZE_BITS) - 1);
 
-  /* Only the first lisplen slots will be traced normally by the GC.  */
-  for (i = 0; i < lisplen; ++i)
-    v->contents[i] = Qnil;
+  /* Only the first lisplen slots will be traced normally by the GC.
+     But since Qnil == 0, we can memset Lisp_Object slots as well.  */
+  memset (v->contents, 0, zerolen * word_size);
 
   XSETPVECTYPESIZE (v, tag, lisplen, memlen - lisplen);
   return v;
@@ -3194,60 +3194,6 @@ allocate_buffer (void)
   return b;
 }
 
-struct Lisp_Hash_Table *
-allocate_hash_table (void)
-{
-  return ALLOCATE_PSEUDOVECTOR (struct Lisp_Hash_Table, count, PVEC_HASH_TABLE);
-}
-
-struct window *
-allocate_window (void)
-{
-  struct window *w;
-
-  w = ALLOCATE_PSEUDOVECTOR (struct window, current_matrix, PVEC_WINDOW);
-  /* Users assumes that non-Lisp data is zeroed.  */
-  memset (&w->current_matrix, 0,
-          sizeof (*w) - offsetof (struct window, current_matrix));
-  return w;
-}
-
-struct terminal *
-allocate_terminal (void)
-{
-  struct terminal *t;
-
-  t = ALLOCATE_PSEUDOVECTOR (struct terminal, next_terminal, PVEC_TERMINAL);
-  /* Users assumes that non-Lisp data is zeroed.  */
-  memset (&t->next_terminal, 0,
-          sizeof (*t) - offsetof (struct terminal, next_terminal));
-  return t;
-}
-
-struct frame *
-allocate_frame (void)
-{
-  struct frame *f;
-
-  f = ALLOCATE_PSEUDOVECTOR (struct frame, face_cache, PVEC_FRAME);
-  /* Users assumes that non-Lisp data is zeroed.  */
-  memset (&f->face_cache, 0,
-          sizeof (*f) - offsetof (struct frame, face_cache));
-  return f;
-}
-
-struct Lisp_Process *
-allocate_process (void)
-{
-  struct Lisp_Process *p;
-
-  p = ALLOCATE_PSEUDOVECTOR (struct Lisp_Process, pid, PVEC_PROCESS);
-  /* Users assumes that non-Lisp data is zeroed.  */
-  memset (&p->pid, 0,
-          sizeof (*p) - offsetof (struct Lisp_Process, pid));
-  return p;
-}
-
 DEFUN ("make-vector", Fmake_vector, Smake_vector, 2, 2, 0,
        doc: /* Return a newly created vector of length LENGTH, with each element being INIT.
 See also the function `vector'.  */)
diff --git a/src/fns.c b/src/fns.c
index 91cd5132546..ca3d98b23dd 100644
--- a/src/fns.c
+++ b/src/fns.c
@@ -3814,6 +3814,15 @@ hashfn_user_defined (struct hash_table_test *ht, Lisp_Object key)
   return hashfn_eq (ht, hash);
 }
 
+/* Allocate basically initialized hash table.  */
+
+static struct Lisp_Hash_Table *
+allocate_hash_table (void)
+{
+  return ALLOCATE_PSEUDOVECTOR (struct Lisp_Hash_Table,
+                                count, PVEC_HASH_TABLE);
+}
+
 /* An upper bound on the size of a hash table index.  It must fit in
    ptrdiff_t and be a valid Emacs fixnum.  */
 #define INDEX_SIZE_BOUND \
diff --git a/src/font.c b/src/font.c
index a68c3c707c8..074e86687a1 100644
--- a/src/font.c
+++ b/src/font.c
@@ -156,7 +156,7 @@ font_make_spec (void)
   struct font_spec *spec
     = ((struct font_spec *)
        allocate_pseudovector (VECSIZE (struct font_spec),
-                              FONT_SPEC_MAX, PVEC_FONT));
+                              FONT_SPEC_MAX, FONT_SPEC_MAX, PVEC_FONT));
   XSETFONT (font_spec, spec);
   return font_spec;
 }
@@ -168,7 +168,7 @@ font_make_entity (void)
   struct font_entity *entity
     = ((struct font_entity *)
        allocate_pseudovector (VECSIZE (struct font_entity),
-                              FONT_ENTITY_MAX, PVEC_FONT));
+                              FONT_ENTITY_MAX, FONT_ENTITY_MAX, PVEC_FONT));
   XSETFONT (font_entity, entity);
   return font_entity;
 }
@@ -181,7 +181,8 @@ font_make_object (int size, Lisp_Object entity, int pixelsize)
 {
   Lisp_Object font_object;
   struct font *font
-    = (struct font *) allocate_pseudovector (size, FONT_OBJECT_MAX, PVEC_FONT);
+    = (struct font *) allocate_pseudovector (size, FONT_OBJECT_MAX,
+                                             FONT_OBJECT_MAX, PVEC_FONT);
   int i;
 
   /* GC can happen before the driver is set up,
diff --git a/src/frame.c b/src/frame.c
index ec580f37c5b..2ce5a623853 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -570,6 +570,13 @@ adjust_frame_size (struct frame *f, int new_width, int new_height, int inhibit,
   run_window_configuration_change_hook (f);
 }
 
+/* Allocate basically initialized frame.  */
+
+static struct frame *
+allocate_frame (void)
+{
+  return ALLOCATE_ZEROED_PSEUDOVECTOR (struct frame, face_cache, PVEC_FRAME);
+}
 
 struct frame *
 make_frame (bool mini_p)
diff --git a/src/lisp.h b/src/lisp.h
index 51556fcc91c..fd0a0342cf8 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -3780,16 +3780,25 @@ make_uninit_sub_char_table (int depth, int min_char)
   return v;
 }
 
-extern struct Lisp_Vector *allocate_pseudovector (int, int, enum pvec_type);
-#define ALLOCATE_PSEUDOVECTOR(typ,field,tag)                            \
-  ((typ*)                                                               \
-   allocate_pseudovector                                                \
-       (VECSIZE (typ), PSEUDOVECSIZE (typ, field), tag))
-extern struct Lisp_Hash_Table *allocate_hash_table (void);
-extern struct window *allocate_window (void);
-extern struct frame *allocate_frame (void);
-extern struct Lisp_Process *allocate_process (void);
-extern struct terminal *allocate_terminal (void);
+extern struct Lisp_Vector *allocate_pseudovector (int, int, int,
+                                                  enum pvec_type);
+
+/* Allocate partially initialized pseudovector where all Lisp_Object
+   slots are set to Qnil but the rest (if any) is left uninitialized.  */
+
+#define ALLOCATE_PSEUDOVECTOR(type, field, tag)                        \
+  ((type *) allocate_pseudovector (VECSIZE (type),                     \
+                                   PSEUDOVECSIZE (type, field),        \
+                                   PSEUDOVECSIZE (type, field), tag))
+
+/* Allocate fully initialized pseudovector where all Lisp_Object
+   slots are set to Qnil and the rest (if any) is zeroed.  */
+
+#define ALLOCATE_ZEROED_PSEUDOVECTOR(type, field, tag)                 \
+  ((type *) allocate_pseudovector (VECSIZE (type),                     \
+                                   PSEUDOVECSIZE (type, field),        \
+                                   VECSIZE (type), tag))
+
 extern bool gc_in_progress;
 extern bool abort_on_gc;
 extern Lisp_Object make_float (double);
diff --git a/src/process.c b/src/process.c
index 77c94f29211..30380548210 100644
--- a/src/process.c
+++ b/src/process.c
@@ -687,7 +687,15 @@ allocate_pty (char pty_name[PTY_NAME_SIZE])
 #endif /* HAVE_PTYS */
   return -1;
 }
-
+
+/* Allocate basically initialized process.  */
+
+static struct Lisp_Process *
+allocate_process (void)
+{
+  return ALLOCATE_ZEROED_PSEUDOVECTOR (struct Lisp_Process, pid, PVEC_PROCESS);
+}
+
 static Lisp_Object
 make_process (Lisp_Object name)
 {
diff --git a/src/terminal.c b/src/terminal.c
index 92befd28543..b48d0623e12 100644
--- a/src/terminal.c
+++ b/src/terminal.c
@@ -254,6 +254,15 @@ get_named_terminal (const char *name)
   return NULL;
 }
 
+/* Allocate basically initialized terminal.  */
+
+static struct terminal *
+allocate_terminal (void)
+{
+  return ALLOCATE_ZEROED_PSEUDOVECTOR
+    (struct terminal, next_terminal, PVEC_TERMINAL);
+}
+
 /* Create a new terminal object of TYPE and add it to the terminal list.  RIF
    may be NULL if this terminal type doesn't support window-based redisplay.  */
 
diff --git a/src/window.c b/src/window.c
index e5ddef5fa40..53a235f8446 100644
--- a/src/window.c
+++ b/src/window.c
@@ -3642,7 +3642,16 @@ temp_output_buffer_show (register Lisp_Object buf)
       }
     }
 }
-
+
+/* Allocate basically initialized window.  */
+
+static struct window *
+allocate_window (void)
+{
+  return ALLOCATE_ZEROED_PSEUDOVECTOR
+    (struct window, current_matrix, PVEC_WINDOW);
+}
+
 /* Make new window, have it replace WINDOW in window-tree, and make
    WINDOW its only vertical child (HORFLAG 1 means make WINDOW its only
    horizontal child).   */