Dual-life perlfaq

[perl5.git] / sv.h

diff --git a/sv.h b/sv.h
index 7f46675..5f58935 100644 (file)
--- a/sv.h
+++ b/sv.h
@@ -367,8 +367,21 @@ perform the upgrade if necessary.  See C<svtype>.
 
 /* PVHV */
 #define SVphv_SHAREKEYS 0x20000000  /* PVHV keys live on shared string table */
-/* PVNV, PVMG, presumably only inside pads */
-#define SVpad_NAME     0x40000000  /* This SV is a name in the PAD, so
+
+/* PVNV, PVMG only, and only used in pads. Should be safe to test on any scalar
+   SV, as the core is careful to avoid setting both.
+
+   SVf_POK, SVp_POK also set:
+   0x00004400   Normal
+   0x0000C400   Studied (SvSCREAM)
+   0x40004400   FBM compiled (SvVALID)
+   0x4000C400   pad name.
+
+   0x00008000   GV with GP
+   0x00008800   RV with PCS imported
+*/
+#define SVpad_NAME     (SVp_SCREAM|SVpbm_VALID)
+                                   /* This SV is a name in the PAD, so
                                       SVpad_TYPED, SVpad_OUR and SVpad_STATE
                                       apply */
 /* PVAV */
@@ -378,11 +391,10 @@ perform the upgrade if necessary.  See C<svtype>.
 /* This is only set true on a PVGV when it's playing "PVBM", but is tested for
    on any regular scalar (anything <= PVLV) */
 #define SVpbm_VALID    0x40000000
-/* ??? */
+/* Only used in toke.c on an SV stored in PL_lex_repl */
 #define SVrepl_EVAL    0x40000000  /* Replacement part of s///e */
 
 /* IV, PVIV, PVNV, PVMG, PVGV and (I assume) PVLV  */
-/* Presumably IVs aren't stored in pads */
 #define SVf_IVisUV     0x80000000  /* use XPVUV instead of XPVIV */
 /* PVAV */
 #define SVpav_REIFY    0x80000000  /* can become real */
@@ -407,8 +419,7 @@ union _xnvu {
        U32 xhigh;
     }      xpad_cop_seq;       /* used by pad.c for cop_sequence */
     struct {
-       U32 xbm_previous;       /* how many characters in string before rare? */
-       U8  xbm_flags;
+       I32 xbm_useful;
        U8  xbm_rare;           /* rarest character in string */
     }      xbm_s;              /* fields from PVBM */
 };
@@ -416,7 +427,6 @@ union _xnvu {
 union _xivu {
     IV     xivu_iv;            /* integer value */
     UV     xivu_uv;
-    I32            xivu_i32;           /* BmUSEFUL */
     HEK *   xivu_namehek;      /* xpvlv, xpvgv: GvNAME */
 };
 
@@ -1003,9 +1013,6 @@ the scalar's value cannot change unless written to.
            ((XPVMG*) SvANY(sv))->xmg_u.xmg_ourstash = st;      \
        } STMT_END
 
-#ifdef PERL_DEBUG_COW
-#else
-#endif
 #define SvRVx(sv) SvRV(sv)
 
 #ifdef PERL_DEBUG_COW
@@ -1280,42 +1287,38 @@ the scalar's value cannot change unless written to.
                 } STMT_END
 #endif
 
-#define PERL_FBM_TABLE_OFFSET 1        /* Number of bytes between EOS and table */
-
 /* SvPOKp not SvPOK in the assertion because the string can be tainted! eg
    perl -T -e '/$^X/'
 */
+
+#ifndef PERL_CORE
+#  define BmFLAGS(sv)          (SvTAIL(sv) ? FBMcf_TAIL : 0)
+#endif
+
 #if defined (DEBUGGING) && defined(__GNUC__) && !defined(PERL_GCC_BRACE_GROUPS_FORBIDDEN)
-#  define BmFLAGS(sv)                                                  \
-       (*({ SV *const _bmflags = MUTABLE_SV(sv);                       \
-               assert(SvTYPE(_bmflags) == SVt_PVGV);                   \
-               assert(SvVALID(_bmflags));                              \
-           &(((XPVGV*) SvANY(_bmflags))->xnv_u.xbm_s.xbm_flags);       \
-        }))
 #  define BmRARE(sv)                                                   \
        (*({ SV *const _bmrare = MUTABLE_SV(sv);                        \
-               assert(SvTYPE(_bmrare) == SVt_PVGV);                    \
+               assert(SvTYPE(_bmrare) == SVt_PVMG);                    \
                assert(SvVALID(_bmrare));                               \
-           &(((XPVGV*) SvANY(_bmrare))->xnv_u.xbm_s.xbm_rare);         \
+           &(((XPVMG*) SvANY(_bmrare))->xnv_u.xbm_s.xbm_rare);         \
         }))
 #  define BmUSEFUL(sv)                                                 \
        (*({ SV *const _bmuseful = MUTABLE_SV(sv);                      \
-           assert(SvTYPE(_bmuseful) == SVt_PVGV);                      \
+           assert(SvTYPE(_bmuseful) == SVt_PVMG);                      \
            assert(SvVALID(_bmuseful));                                 \
            assert(!SvIOK(_bmuseful));                                  \
-           &(((XPVGV*) SvANY(_bmuseful))->xiv_u.xivu_i32);             \
+           &(((XPVMG*) SvANY(_bmuseful))->xnv_u.xbm_s.xbm_useful);     \
         }))
 #  define BmPREVIOUS(sv)                                               \
     (*({ SV *const _bmprevious = MUTABLE_SV(sv);                       \
-               assert(SvTYPE(_bmprevious) == SVt_PVGV);                \
+               assert(SvTYPE(_bmprevious) == SVt_PVMG);                \
                assert(SvVALID(_bmprevious));                           \
-           &(((XPVGV*) SvANY(_bmprevious))->xnv_u.xbm_s.xbm_previous); \
+           &(((XPVMG*) SvANY(_bmprevious))->xiv_u.xivu_uv);            \
         }))
 #else
-#  define BmFLAGS(sv)          ((XPVGV*) SvANY(sv))->xnv_u.xbm_s.xbm_flags
-#  define BmRARE(sv)           ((XPVGV*) SvANY(sv))->xnv_u.xbm_s.xbm_rare
-#  define BmUSEFUL(sv)         ((XPVGV*) SvANY(sv))->xiv_u.xivu_i32
-#  define BmPREVIOUS(sv)       ((XPVGV*) SvANY(sv))->xnv_u.xbm_s.xbm_previous
+#  define BmRARE(sv)           ((XPVMG*) SvANY(sv))->xnv_u.xbm_s.xbm_rare
+#  define BmUSEFUL(sv)         ((XPVMG*) SvANY(sv))->xnv_u.xbm_s.xbm_useful
+#  define BmPREVIOUS(sv)       ((XPVMG*) SvANY(sv))->xiv_u.xivu_uv
 
 #endif