Add a depth field to formats

Instead of lengthening the struct, we can reuse SvCUR, which is cur-
rently unused.

4 files changed, 22 insertions, 8 deletions

diff --git a/cv.h b/cv.h
index e2644e1de1..a94d2481bd 100644
--- a/cv.h
+++ b/cv.h
@@ -61,13 +61,21 @@ See L<perlguts/Autoloading with XSUBs>.
     (CvFILE(sv) = CopFILE(cop), CvDYNFILE_off(sv))
 #endif
 #define CvFILEGV(sv)	(gv_fetchfile(CvFILE(sv)))
+PERL_STATIC_INLINE I32 *
+S_CvDEPTHp(const CV * const sv)
+{
+    return SvTYPE(sv) == SVt_PVCV
+	? &((XPVCV*)SvANY(sv))->xcv_depth
+	: &((XPVCV*)SvANY(sv))->xpv_cur_u.xpvcuru_fmdepth;
+}
 #if defined(__GNUC__) && !defined(PERL_GCC_BRACE_GROUPS_FORBIDDEN)
 #  define CvDEPTH(sv) (*({const CV *const _cvdepth = (const CV *)sv; \
-			  assert(SvTYPE(_cvdepth) == SVt_PVCV);	 \
-			  &((XPVCV*)SvANY(_cvdepth))->xcv_depth; \
+			  assert(SvTYPE(_cvdepth) == SVt_PVCV	      \
+			      || SvTYPE(_cvdepth) == SVt_PVFM);	       \
+			  S_CvDEPTHp(_cvdepth);				\
 			}))
 #else
-#  define CvDEPTH(sv)	((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_depth
+#  define CvDEPTH(sv)	*S_CvDEPTHp((const CV *)sv)
 #endif
 #define CvPADLIST(sv)	((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_padlist
 #define CvOUTSIDE(sv)	((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_outside
diff --git a/dump.c b/dump.c
index ca5d12584c..0c5cc75d81 100644
--- a/dump.c
+++ b/dump.c
@@ -1920,8 +1920,7 @@ Perl_do_sv_dump(pTHX_ I32 level, PerlIO *file, SV *sv, I32 nest, I32 maxnest, bo
 	}
  	do_gvgv_dump(level, file, "  GVGV::GV", CvGV(sv));
 	Perl_dump_indent(aTHX_ level, file, "  FILE = \"%s\"\n", CvFILE(sv));
-	if (type == SVt_PVCV)
-	    Perl_dump_indent(aTHX_ level, file, "  DEPTH = %"IVdf"\n", (IV)CvDEPTH(sv));
+	Perl_dump_indent(aTHX_ level, file, "  DEPTH = %"IVdf"\n", (IV)CvDEPTH(sv));
 	Perl_dump_indent(aTHX_ level, file, "  FLAGS = 0x%"UVxf"\n", (UV)CvFLAGS(sv));
 	Perl_dump_indent(aTHX_ level, file, "  OUTSIDE_SEQ = %"UVuf"\n", (UV)CvOUTSIDE_SEQ(sv));
 	Perl_dump_indent(aTHX_ level, file, "  PADLIST = 0x%"UVxf"\n", PTR2UV(CvPADLIST(sv)));
diff --git a/ext/B/B.xs b/ext/B/B.xs
index 9c9133b9ff..2c3d7f8b94 100644
--- a/ext/B/B.xs
+++ b/ext/B/B.xs
@@ -1449,7 +1449,6 @@ MODULE = B	PACKAGE = B::IV
 #define PVCV_stash_ix	sv_SVp | offsetof(struct xpvcv, xcv_stash) 
 #define PVCV_gv_ix	sv_SVp | offsetof(struct xpvcv, xcv_gv)
 #define PVCV_file_ix	sv_char_pp | offsetof(struct xpvcv, xcv_file)
-#define PVCV_depth_ix	sv_I32p | offsetof(struct xpvcv, xcv_depth)
 #define PVCV_padlist_ix	sv_SVp | offsetof(struct xpvcv, xcv_padlist)
 #define PVCV_outside_ix	sv_SVp | offsetof(struct xpvcv, xcv_outside)
 #define PVCV_outside_seq_ix sv_U32p | offsetof(struct xpvcv, xcv_outside_seq)
@@ -1505,7 +1504,6 @@ IVX(sv)
 	B::CV::STASH = PVCV_stash_ix
 	B::CV::GV = PVCV_gv_ix
 	B::CV::FILE = PVCV_file_ix
-	B::CV::DEPTH = PVCV_depth_ix
 	B::CV::PADLIST = PVCV_padlist_ix
 	B::CV::OUTSIDE = PVCV_outside_ix
 	B::CV::OUTSIDE_SEQ = PVCV_outside_seq_ix
@@ -1984,6 +1982,10 @@ CvSTART(cv)
 	PUSHs(make_op_object(aTHX_ CvISXSUB(cv) ? NULL
 			     : ix ? CvROOT(cv) : CvSTART(cv)));
 
+I32
+CvDEPTH(cv)
+        B::CV   cv
+
 void
 CvXSUB(cv)
 	B::CV	cv
diff --git a/sv.h b/sv.h
index b2385d0a6d..4c9bc55e92 100644
--- a/sv.h
+++ b/sv.h
@@ -415,9 +415,14 @@ perform the upgrade if necessary.  See C<svtype>.
 #define _XPV_HEAD							\
     HV*		xmg_stash;	/* class package */			\
     union _xmgu	xmg_u;							\
-    STRLEN	xpv_cur;	/* length of svu_pv as a C string */    \
+    union {								\
+	STRLEN	xpvcuru_cur;	/* length of svu_pv as a C string */    \
+	I32	xpvcuru_fmdepth;					\
+    }		xpv_cur_u;						\
     STRLEN	xpv_len 	/* allocated size */
 
+#define xpv_cur	xpv_cur_u.xpvcuru_cur
+
 union _xnvu {
     NV	    xnv_nv;		/* numeric value, if any */
     HV *    xgv_stash;