Change the IV to a union.

[perl5.git] / av.h

diff --git a/av.h b/av.h
index bacf614..f8dffc9 100644 (file)
--- a/av.h
+++ b/av.h
@@ -1,6 +1,7 @@
 /*    av.h
  *
- *    Copyright (c) 1991-1999, Larry Wall
+ *    Copyright (C) 1991, 1992, 1993, 1995, 1996, 1997, 1998, 1999,
+ *    2000, 2001, 2002, 2005, by Larry Wall and others
  *
  *    You may distribute under the terms of either the GNU General Public
  *    License or the Artistic License, as specified in the README file.
@@ -8,44 +9,102 @@
  */
 
 struct xpvav {
-    char*      xav_array;      /* pointer to first array element */
-    SSize_t    xav_fill;       /* Index of last element present */
-    SSize_t    xav_max;        /* Number of elements for which array has space */
-    IV         xof_off;        /* ptr is incremented by offset */
     NV         xnv_nv;         /* numeric value, if any */
+    SSize_t    xav_fill;       /* Index of last element present */
+    SSize_t    xav_max;        /* max index for which array has space */
+    union {
+       IV      xivu_iv;        /* integer value or pv offset */
+       UV      xivu_uv;
+       void *  xivu_p1;
+    }          xiv_u;
     MAGIC*     xmg_magic;      /* magic for scalar array */
     HV*                xmg_stash;      /* class package */
-
-    SV**       xav_alloc;      /* pointer to malloced string */
     SV*                xav_arylen;
-    U8         xav_flags;
 };
 
-#define AVf_REAL 1     /* free old entries */
-#define AVf_REIFY 2    /* can become real */
-#define AVf_REUSED 4   /* got undeffed--don't turn old memory into SVs now */
+#if !defined(PERL_EXPERIMENTAL_LAYOUT)
+typedef struct xpvav xpvav_allocated;
+#else
+typedef struct {
+    SSize_t    xav_fill;       /* Index of last element present */
+    SSize_t    xav_max;        /* max index for which array has space */
+    union {
+       IV      xivu_iv;        /* integer value or pv offset */
+       UV      xivu_uv;
+       void *  xivu_p1;
+    }          xiv_u;
+    MAGIC*     xmg_magic;      /* magic for scalar array */
+    HV*                xmg_stash;      /* class package */
+    SV*                xav_arylen;
+} xpvav_allocated;
+#endif
+
+/* SV**        xav_alloc; */
+#define xav_alloc xiv_u.xivu_p1
+/* SV* xav_arylen; */
+
+/* AVf_REAL is set for all AVs whose xav_array contents are refcounted.
+ * Some things like "@_" and the scratchpad list do not set this, to
+ * indicate that they are cheating (for efficiency) by not refcounting
+ * the AV's contents.
+ * 
+ * AVf_REIFY is only meaningful on such "fake" AVs (i.e. where AVf_REAL
+ * is not set).  It indicates that the fake AV is capable of becoming
+ * real if the array needs to be modified in some way.  Functions that
+ * modify fake AVs check both flags to call av_reify() as appropriate.
+ *
+ * Note that the Perl stack and @DB::args have neither flag set. (Thus,
+ * items that go on the stack are never refcounted.)
+ *
+ * These internal details are subject to change any time.  AV
+ * manipulations external to perl should not care about any of this.
+ * GSAR 1999-09-10
+ */
+
+/*
+=head1 Handy Values
+
+=for apidoc AmU||Nullav
+Null AV pointer.
+
+=head1 Array Manipulation Functions
+
+=for apidoc Am|int|AvFILL|AV* av
+Same as C<av_len()>.  Deprecated, use C<av_len()> instead.
+
+=cut
+*/
 
 #define Nullav Null(AV*)
 
-#define AvARRAY(av)    ((SV**)((XPVAV*)  SvANY(av))->xav_array)
-#define AvALLOC(av)    ((XPVAV*)  SvANY(av))->xav_alloc
+#define AvARRAY(av)    ((av)->sv_u.svu_array)
+#define AvALLOC(av)    (*((SV***)&((XPVAV*)  SvANY(av))->xav_alloc))
 #define AvMAX(av)      ((XPVAV*)  SvANY(av))->xav_max
 #define AvFILLp(av)    ((XPVAV*)  SvANY(av))->xav_fill
-#define AvARYLEN(av)   ((XPVAV*)  SvANY(av))->xav_arylen
-#define AvFLAGS(av)    ((XPVAV*)  SvANY(av))->xav_flags
-
-#define AvREAL(av)     (AvFLAGS(av) & AVf_REAL)
-#define AvREAL_on(av)  (AvFLAGS(av) |= AVf_REAL)
-#define AvREAL_off(av) (AvFLAGS(av) &= ~AVf_REAL)
-#define AvREIFY(av)    (AvFLAGS(av) & AVf_REIFY)
-#define AvREIFY_on(av) (AvFLAGS(av) |= AVf_REIFY)
-#define AvREIFY_off(av)        (AvFLAGS(av) &= ~AVf_REIFY)
-#define AvREUSED(av)   (AvFLAGS(av) & AVf_REUSED)
-#define AvREUSED_on(av)        (AvFLAGS(av) |= AVf_REUSED)
-#define AvREUSED_off(av) (AvFLAGS(av) &= ~AVf_REUSED)
-
-#define AvREALISH(av)  (AvFLAGS(av) & (AVf_REAL|AVf_REIFY))
+#define AvARYLEN(av)   (*((SV**)&((XPVAV*)  SvANY(av))->xav_arylen))
+
+#define AvREAL(av)     (SvFLAGS(av) & SVpav_REAL)
+#define AvREAL_on(av)  (SvFLAGS(av) |= SVpav_REAL)
+#define AvREAL_off(av) (SvFLAGS(av) &= ~SVpav_REAL)
+#define AvREAL_only(av)        (AvREIFY_off(av), SvFLAGS(av) |= SVpav_REAL)
+#define AvREIFY(av)    (SvFLAGS(av) & SVpav_REIFY)
+#define AvREIFY_on(av) (SvFLAGS(av) |= SVpav_REIFY)
+#define AvREIFY_off(av)        (SvFLAGS(av) &= ~SVpav_REIFY)
+#define AvREIFY_only(av)       (AvREAL_off(av), SvFLAGS(av) |= SVpav_REIFY)
+
+#define AvREALISH(av)  (SvFLAGS(av) & (SVpav_REAL|SVpav_REIFY))
                                           
 #define AvFILL(av)     ((SvRMAGICAL((SV *) (av))) \
                          ? mg_size((SV *) av) : AvFILLp(av))
 
+#define NEGATIVE_INDICES_VAR "NEGATIVE_INDICES"
+
+/*
+ * Local variables:
+ * c-indentation-style: bsd
+ * c-basic-offset: 4
+ * indent-tabs-mode: t
+ * End:
+ *
+ * ex: set ts=8 sts=4 sw=4 noet:
+ */