Split the XPVHV body into two variants "normal" and "with aux"

Default to the smaller body, and switch to the larger body if we need to
allocate a C<struct xpvhv_aux> (eg need an iterator).

This restores the previous small size optimisation for hashes used as
objects.

1 files changed, 8 insertions, 1 deletions

diff --git a/hv.h b/hv.h
index 285a004a5f..c7aeb7de57 100644
--- a/hv.h
+++ b/hv.h
@@ -137,6 +137,13 @@ struct xpvhv {
     union _xmgu	xmg_u;
     STRLEN      xhv_keys;       /* total keys, including placeholders */
     STRLEN      xhv_max;        /* subscript of last element of xhv_array */
+};
+
+struct xpvhv_with_aux {
+    HV         *xmg_stash;      /* class package */
+    union _xmgu xmg_u;
+    STRLEN      xhv_keys;       /* total keys, including placeholders */
+    STRLEN      xhv_max;        /* subscript of last element of xhv_array */
     struct xpvhv_aux xhv_aux;
 };
 
@@ -264,7 +271,7 @@ See L</hv_fill>.
 #define HvMAX(hv)	((XPVHV*)  SvANY(hv))->xhv_max
 /* This quite intentionally does no flag checking first. That's your
    responsibility.  */
-#define HvAUX(hv)       (&(((XPVHV*) SvANY(hv))->xhv_aux))
+#define HvAUX(hv)       (&(((struct xpvhv_with_aux*)  SvANY(hv))->xhv_aux))
 #define HvRITER(hv)	(*Perl_hv_riter_p(aTHX_ MUTABLE_HV(hv)))
 #define HvEITER(hv)	(*Perl_hv_eiter_p(aTHX_ MUTABLE_HV(hv)))
 #define HvRITER_set(hv,r)	Perl_hv_riter_set(aTHX_ MUTABLE_HV(hv), r)