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Skip no-common-vars optimisation for aliases
[perl5.git] / scope.h
diff --git a/scope.h b/scope.h
index 73b94cb..cad02cd 100644 (file)
--- a/scope.h
+++ b/scope.h
 /*    scope.h
  *
- *    Copyright (C) 1993, 1994, 1996, 1997, 1998, 1999,
- *    2000, 2001, 2002, 2004, 2005 by Larry Wall and others
+ *    Copyright (C) 1993, 1994, 1996, 1997, 1998, 1999, 2000, 2001,
+ *    2002, 2004, 2005, 2006, 2007, 2008 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.
  *
  */
 
-#define SAVEt_ITEM             0
-#define SAVEt_SV               1
-#define SAVEt_AV               2
-#define SAVEt_HV               3
-#define SAVEt_INT              4
-#define SAVEt_LONG             5
-#define SAVEt_I32              6
-#define SAVEt_IV               7
-#define SAVEt_SPTR             8
-#define SAVEt_APTR             9
-#define SAVEt_HPTR             10
-#define SAVEt_PPTR             11
-#define SAVEt_NSTAB            12
-#define SAVEt_SVREF            13
-#define SAVEt_GP               14
-#define SAVEt_FREESV           15
-#define SAVEt_FREEOP           16
-#define SAVEt_FREEPV           17
-#define SAVEt_CLEARSV          18
-#define SAVEt_DELETE           19
-#define SAVEt_DESTRUCTOR       20
-#define SAVEt_REGCONTEXT       21
-#define SAVEt_STACK_POS                22
-#define SAVEt_I16              23
-#define SAVEt_AELEM            24
-#define SAVEt_HELEM            25
-#define SAVEt_OP               26
-#define SAVEt_HINTS            27
-#define SAVEt_ALLOC            28
-#define SAVEt_GENERIC_SVREF    29
-#define SAVEt_DESTRUCTOR_X     30
-#define SAVEt_VPTR             31
-#define SAVEt_I8               32
-#define SAVEt_COMPPAD          33
-#define SAVEt_GENERIC_PVREF    34
-#define SAVEt_PADSV            35
-#define SAVEt_MORTALIZESV      36
-#define SAVEt_SHARED_PVREF     37
-#define SAVEt_BOOL             38
-#define SAVEt_SET_SVFLAGS      39
-#define SAVEt_SAVESWITCHSTACK  40
+/* *** these are ordered by number of of auto-popped args */
+
+/* zero args */
+
+#define SAVEt_ALLOC            0
+#define SAVEt_CLEARPADRANGE    1
+#define SAVEt_CLEARSV          2
+#define SAVEt_REGCONTEXT       3
+
+#define SAVEt_ARG0_MAX         3
+
+/* one arg */
+
+#define SAVEt_GP_ALIASED_SV    4
+#define SAVEt_BOOL             5
+#define SAVEt_COMPILE_WARNINGS 6
+#define SAVEt_COMPPAD          7
+#define SAVEt_FREECOPHH                8
+#define SAVEt_FREEOP           9
+#define SAVEt_FREEPV           10
+#define SAVEt_FREESV           11
+#define SAVEt_I16              12
+#define SAVEt_I32_SMALL                13
+#define SAVEt_I8               14
+#define SAVEt_INT_SMALL                15
+#define SAVEt_MORTALIZESV      16
+#define SAVEt_NSTAB            17
+#define SAVEt_OP               18
+#define SAVEt_PARSER           19
+#define SAVEt_STACK_POS                20
+#define SAVEt_READONLY_OFF     21
+
+#define SAVEt_ARG1_MAX         21
+
+/* two args */
+
+#define SAVEt_APTR             22
+#define SAVEt_AV               23
+#define SAVEt_DESTRUCTOR       24
+#define SAVEt_DESTRUCTOR_X     25
+#define SAVEt_GENERIC_PVREF    26
+#define SAVEt_GENERIC_SVREF    27
+#define SAVEt_GP               28
+#define SAVEt_GVSV             29
+#define SAVEt_HINTS            30
+#define SAVEt_HPTR             31
+#define SAVEt_HV               32
+#define SAVEt_I32              33
+#define SAVEt_INT              34
+#define SAVEt_ITEM             35
+#define SAVEt_IV               36
+#define SAVEt_LONG             37
+#define SAVEt_PPTR             38
+#define SAVEt_SAVESWITCHSTACK  39
+#define SAVEt_SHARED_PVREF     40
+#define SAVEt_SPTR             41
+#define SAVEt_STRLEN           42
+#define SAVEt_SV               43
+#define SAVEt_SVREF            44
+#define SAVEt_VPTR             45
+#define SAVEt_ADELETE          46
+
+#define SAVEt_ARG2_MAX         46
+
+/* three args */
+
+#define SAVEt_DELETE           47
+#define SAVEt_HELEM            48
+#define SAVEt_PADSV_AND_MORTALIZE 49
+#define SAVEt_SET_SVFLAGS      50
+#define SAVEt_GVSLOT           51
+#define SAVEt_AELEM            52
+
+#define SAVEf_SETMAGIC         1
+#define SAVEf_KEEPOLDELEM      2
+
+#define SAVE_TIGHT_SHIFT       6
+#define SAVE_MASK              0x3F
+
+#define save_aelem(av,idx,sptr)        save_aelem_flags(av,idx,sptr,SAVEf_SETMAGIC)
+#define save_helem(hv,key,sptr)        save_helem_flags(hv,key,sptr,SAVEf_SETMAGIC)
 
 #ifndef SCOPE_SAVES_SIGNAL_MASK
 #define SCOPE_SAVES_SIGNAL_MASK 0
 #endif
 
-#define SSCHECK(need) if (PL_savestack_ix + (need) > PL_savestack_max) savestack_grow()
-#define SSGROW(need) if (PL_savestack_ix + (need) > PL_savestack_max) savestack_grow_cnt(need)
+/* the maximum number of entries that might be pushed using the SS_ADD*
+ * macros */
+#define SS_MAXPUSH 4
+
+#define SSCHECK(need) if (UNLIKELY(PL_savestack_ix + (I32)(need) + SS_MAXPUSH > PL_savestack_max)) savestack_grow()
+#define SSGROW(need) if (UNLIKELY(PL_savestack_ix + (I32)(need) + SS_MAXPUSH > PL_savestack_max)) savestack_grow_cnt(need + SS_MAXPUSH)
 #define SSPUSHINT(i) (PL_savestack[PL_savestack_ix++].any_i32 = (I32)(i))
 #define SSPUSHLONG(i) (PL_savestack[PL_savestack_ix++].any_long = (long)(i))
 #define SSPUSHBOOL(p) (PL_savestack[PL_savestack_ix++].any_bool = (p))
 #define SSPUSHIV(i) (PL_savestack[PL_savestack_ix++].any_iv = (IV)(i))
+#define SSPUSHUV(u) (PL_savestack[PL_savestack_ix++].any_uv = (UV)(u))
 #define SSPUSHPTR(p) (PL_savestack[PL_savestack_ix++].any_ptr = (void*)(p))
 #define SSPUSHDPTR(p) (PL_savestack[PL_savestack_ix++].any_dptr = (p))
 #define SSPUSHDXPTR(p) (PL_savestack[PL_savestack_ix++].any_dxptr = (p))
+
+/* SS_ADD*: newer, faster versions of the above. Don't mix the two sets of
+ * macros. These are fast because they save reduce accesses to the PL_
+ * vars and move the size check to the end. Doing the check last means
+ * that values in registers will have been pushed and no longer needed, so
+ * don't need saving around the call to grow. Also, tail-call elimination
+ * of the grow() can be done. These changes reduce the code of something
+ * like save_pushptrptr() to half its former size.
+ * Of course, doing the size check *after* pushing means we must always
+ * ensure there are SS_MAXPUSH free slots on the savestack
+ *
+ * These are for internal core use only and are subject to change */
+
+#define dSS_ADD \
+    I32 ix = PL_savestack_ix;     \
+    ANY *ssp = &PL_savestack[ix]
+
+#define SS_ADD_END(need) \
+    assert((need) <= SS_MAXPUSH);                               \
+    ix += (need);                                               \
+    PL_savestack_ix = ix;                                       \
+    assert(ix <= PL_savestack_max);                             \
+    if (UNLIKELY((ix + SS_MAXPUSH) > PL_savestack_max)) savestack_grow(); \
+    assert(PL_savestack_ix + SS_MAXPUSH <= PL_savestack_max);
+
+#define SS_ADD_INT(i)   ((ssp++)->any_i32 = (I32)(i))
+#define SS_ADD_LONG(i)  ((ssp++)->any_long = (long)(i))
+#define SS_ADD_BOOL(p)  ((ssp++)->any_bool = (p))
+#define SS_ADD_IV(i)    ((ssp++)->any_iv = (IV)(i))
+#define SS_ADD_UV(u)    ((ssp++)->any_uv = (UV)(u))
+#define SS_ADD_PTR(p)   ((ssp++)->any_ptr = (void*)(p))
+#define SS_ADD_DPTR(p)  ((ssp++)->any_dptr = (p))
+#define SS_ADD_DXPTR(p) ((ssp++)->any_dxptr = (p))
+
 #define SSPOPINT (PL_savestack[--PL_savestack_ix].any_i32)
 #define SSPOPLONG (PL_savestack[--PL_savestack_ix].any_long)
 #define SSPOPBOOL (PL_savestack[--PL_savestack_ix].any_bool)
 #define SSPOPIV (PL_savestack[--PL_savestack_ix].any_iv)
+#define SSPOPUV (PL_savestack[--PL_savestack_ix].any_uv)
 #define SSPOPPTR (PL_savestack[--PL_savestack_ix].any_ptr)
 #define SSPOPDPTR (PL_savestack[--PL_savestack_ix].any_dptr)
 #define SSPOPDXPTR (PL_savestack[--PL_savestack_ix].any_dxptr)
 
+
 /*
 =head1 Callback Functions
 
@@ -88,10 +169,25 @@ Opening bracket on a callback.  See C<LEAVE> and L<perlcall>.
 =for apidoc Ams||LEAVE
 Closing bracket on a callback.  See C<ENTER> and L<perlcall>.
 
+=over
+
+=item ENTER_with_name(name)
+
+Same as C<ENTER>, but when debugging is enabled it also associates the
+given literal string with the new scope.
+
+=item LEAVE_with_name(name)
+
+Same as C<LEAVE>, but when debugging is enabled it first checks that the
+scope has the given name. Name must be a literal string.
+
+=back
+
 =cut
 */
 
-#define SAVETMPS save_int((int*)&PL_tmps_floor), PL_tmps_floor = PL_tmps_ix
+#define SAVETMPS Perl_save_strlen(aTHX_ (STRLEN *)&PL_tmps_floor), \
+                PL_tmps_floor = PL_tmps_ix
 #define FREETMPS if (PL_tmps_ix > PL_tmps_floor) free_tmps()
 
 #ifdef DEBUGGING
@@ -105,89 +201,103 @@ Closing bracket on a callback.  See C<ENTER> and L<perlcall>.
        DEBUG_SCOPE("LEAVE")                                    \
        pop_scope();                                            \
     } STMT_END
+#define ENTER_with_name(name)                                          \
+    STMT_START {                                                       \
+       push_scope();                                                   \
+       if (PL_scopestack_name)                                         \
+           PL_scopestack_name[PL_scopestack_ix-1] = name;              \
+       DEBUG_SCOPE("ENTER \"" name "\"")                               \
+    } STMT_END
+#define LEAVE_with_name(name)                                          \
+    STMT_START {                                                       \
+       DEBUG_SCOPE("LEAVE \"" name "\"")                               \
+       if (PL_scopestack_name) {                                       \
+           assert(((char*)PL_scopestack_name[PL_scopestack_ix-1]       \
+                       == (char*)name)                                 \
+                   || strEQ(PL_scopestack_name[PL_scopestack_ix-1], name));        \
+       }                                                               \
+       pop_scope();                                                    \
+    } STMT_END
 #else
 #define ENTER push_scope()
 #define LEAVE pop_scope()
+#define ENTER_with_name(name) ENTER
+#define LEAVE_with_name(name) LEAVE
 #endif
-#define LEAVE_SCOPE(old) if (PL_savestack_ix > old) leave_scope(old)
+#define LEAVE_SCOPE(old) STMT_START { \
+       if (PL_savestack_ix > old) leave_scope(old); \
+    } STMT_END
 
-/*
- * Not using SOFT_CAST on SAVESPTR, SAVEGENERICSV and SAVEFREESV
- * because these are used for several kinds of pointer values
- */
-#define SAVEI8(i)      save_I8(SOFT_CAST(I8*)&(i))
-#define SAVEI16(i)     save_I16(SOFT_CAST(I16*)&(i))
-#define SAVEI32(i)     save_I32(SOFT_CAST(I32*)&(i))
-#define SAVEINT(i)     save_int(SOFT_CAST(int*)&(i))
-#define SAVEIV(i)      save_iv(SOFT_CAST(IV*)&(i))
-#define SAVELONG(l)    save_long(SOFT_CAST(long*)&(l))
-#define SAVEBOOL(b)    save_bool(SOFT_CAST(bool*)&(b))
+#define SAVEI8(i)      save_I8((I8*)&(i))
+#define SAVEI16(i)     save_I16((I16*)&(i))
+#define SAVEI32(i)     save_I32((I32*)&(i))
+#define SAVEINT(i)     save_int((int*)&(i))
+#define SAVEIV(i)      save_iv((IV*)&(i))
+#define SAVELONG(l)    save_long((long*)&(l))
+#define SAVEBOOL(b)    save_bool(&(b))
 #define SAVESPTR(s)    save_sptr((SV**)&(s))
-#define SAVEPPTR(s)    save_pptr(SOFT_CAST(char**)&(s))
+#define SAVEPPTR(s)    save_pptr((char**)&(s))
 #define SAVEVPTR(s)    save_vptr((void*)&(s))
-#define SAVEPADSV(s)   save_padsv(s)
-#define SAVEFREESV(s)  save_freesv((SV*)(s))
-#define SAVEMORTALIZESV(s)     save_mortalizesv((SV*)(s))
-#define SAVEFREEOP(o)  save_freeop(SOFT_CAST(OP*)(o))
-#define SAVEFREEPV(p)  save_freepv(SOFT_CAST(char*)(p))
-#define SAVECLEARSV(sv)        save_clearsv(SOFT_CAST(SV**)&(sv))
+#define SAVEPADSVANDMORTALIZE(s)       save_padsv_and_mortalize(s)
+#define SAVEFREESV(s)  save_freesv(MUTABLE_SV(s))
+#define SAVEMORTALIZESV(s)     save_mortalizesv(MUTABLE_SV(s))
+#define SAVEFREEOP(o)  save_freeop((OP*)(o))
+#define SAVEFREEPV(p)  save_freepv((char*)(p))
+#define SAVECLEARSV(sv)        save_clearsv((SV**)&(sv))
 #define SAVEGENERICSV(s)       save_generic_svref((SV**)&(s))
 #define SAVEGENERICPV(s)       save_generic_pvref((char**)&(s))
 #define SAVESHAREDPV(s)                save_shared_pvref((char**)&(s))
 #define SAVESETSVFLAGS(sv,mask,val)    save_set_svflags(sv,mask,val)
+#define SAVEFREECOPHH(h)       save_pushptr((void *)(h), SAVEt_FREECOPHH)
 #define SAVEDELETE(h,k,l) \
-         save_delete(SOFT_CAST(HV*)(h), SOFT_CAST(char*)(k), (I32)(l))
+         save_delete(MUTABLE_HV(h), (char*)(k), (I32)(l))
+#define SAVEHDELETE(h,s) \
+         save_hdelete(MUTABLE_HV(h), (s))
+#define SAVEADELETE(a,k) \
+         save_adelete(MUTABLE_AV(a), (SSize_t)(k))
 #define SAVEDESTRUCTOR(f,p) \
-         save_destructor((DESTRUCTORFUNC_NOCONTEXT_t)(f), SOFT_CAST(void*)(p))
+         save_destructor((DESTRUCTORFUNC_NOCONTEXT_t)(f), (void*)(p))
 
 #define SAVEDESTRUCTOR_X(f,p) \
-         save_destructor_x((DESTRUCTORFUNC_t)(f), SOFT_CAST(void*)(p))
+         save_destructor_x((DESTRUCTORFUNC_t)(f), (void*)(p))
 
 #define SAVESTACK_POS() \
-    STMT_START {                               \
-       SSCHECK(2);                             \
-       SSPUSHINT(PL_stack_sp - PL_stack_base); \
-       SSPUSHINT(SAVEt_STACK_POS);             \
+    STMT_START {                                  \
+        dSS_ADD;                                   \
+        SS_ADD_INT(PL_stack_sp - PL_stack_base);   \
+        SS_ADD_UV(SAVEt_STACK_POS);                \
+        SS_ADD_END(2);                             \
     } STMT_END
 
 #define SAVEOP()       save_op()
 
-#define SAVEHINTS() \
-    STMT_START {                                       \
-       SSCHECK(3);                                     \
-       if (PL_hints & HINT_LOCALIZE_HH) {              \
-           SSPUSHPTR(GvHV(PL_hintgv));                 \
-           GvHV(PL_hintgv) = newHVhv(GvHV(PL_hintgv)); \
-       }                                               \
-       SSPUSHINT(PL_hints);                            \
-       SSPUSHINT(SAVEt_HINTS);                         \
-    } STMT_END
+#define SAVEHINTS()    save_hints()
 
-#define SAVECOMPPAD() \
-    STMT_START {                                               \
-       SSCHECK(2);                                             \
-       SSPUSHPTR((SV*)PL_comppad);                             \
-       SSPUSHINT(SAVEt_COMPPAD);                               \
-    } STMT_END
+#define SAVECOMPPAD() save_pushptr(MUTABLE_SV(PL_comppad), SAVEt_COMPPAD)
 
 #define SAVESWITCHSTACK(f,t) \
     STMT_START {                                       \
-       SSCHECK(3);                                     \
-       SSPUSHPTR((SV*)(f));                            \
-       SSPUSHPTR((SV*)(t));                            \
-       SSPUSHINT(SAVEt_SAVESWITCHSTACK);               \
+       save_pushptrptr(MUTABLE_SV(f), MUTABLE_SV(t), SAVEt_SAVESWITCHSTACK); \
        SWITCHSTACK((f),(t));                           \
        PL_curstackinfo->si_stack = (t);                \
     } STMT_END
 
+/* Need to do the cop warnings like this, rather than a "SAVEFREESHAREDPV",
+   because realloc() means that the value can actually change. Possibly
+   could have done savefreesharedpvREF, but this way actually seems cleaner,
+   as it simplifies the code that does the saves, and reduces the load on the
+   save stack.  */
+#define SAVECOMPILEWARNINGS() save_pushptr(PL_compiling.cop_warnings, SAVEt_COMPILE_WARNINGS)
+
+#define SAVEPARSER(p) save_pushptr((p), SAVEt_PARSER)
+
 #ifdef USE_ITHREADS
-#  define SAVECOPSTASH(c)      SAVEPPTR(CopSTASHPV(c))
-#  define SAVECOPSTASH_FREE(c) SAVESHAREDPV(CopSTASHPV(c))
+#  define SAVECOPSTASH_FREE(c) SAVEIV((c)->cop_stashoff)
 #  define SAVECOPFILE(c)       SAVEPPTR(CopFILE(c))
 #  define SAVECOPFILE_FREE(c)  SAVESHAREDPV(CopFILE(c))
 #else
-#  define SAVECOPSTASH(c)      SAVESPTR(CopSTASH(c))
-#  define SAVECOPSTASH_FREE(c) SAVECOPSTASH(c) /* XXX not refcounted */
+#  /* XXX not refcounted */
+#  define SAVECOPSTASH_FREE(c) SAVESPTR(CopSTASH(c))
 #  define SAVECOPFILE(c)       SAVESPTR(CopFILEGV(c))
 #  define SAVECOPFILE_FREE(c)  SAVEGENERICSV(CopFILEGV(c))
 #endif
@@ -199,8 +309,8 @@ Closing bracket on a callback.  See C<ENTER> and L<perlcall>.
  * pointer would get broken if the savestack is moved on reallocation.
  * SSNEWa() works like SSNEW(), but also aligns the data to the specified
  * number of bytes.  MEM_ALIGNBYTES is perhaps the most useful.  The
- * alignment will be preserved therough savestack reallocation *only* if
- * realloc returns data aligned to a size divisible by `align'!
+ * alignment will be preserved through savestack reallocation *only* if
+ * realloc returns data aligned to a size divisible by "align"!
  *
  * SSPTR() converts the index returned by SSNEW/SSNEWa() into a pointer.
  */
@@ -208,126 +318,31 @@ Closing bracket on a callback.  See C<ENTER> and L<perlcall>.
 #define SSNEW(size)             Perl_save_alloc(aTHX_ (size), 0)
 #define SSNEWt(n,t)             SSNEW((n)*sizeof(t))
 #define SSNEWa(size,align)     Perl_save_alloc(aTHX_ (size), \
-    (align - ((int)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align)
+    (I32)(align - ((size_t)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align)
 #define SSNEWat(n,t,align)     SSNEWa((n)*sizeof(t), align)
 
 #define SSPTR(off,type)         ((type)  ((char*)PL_savestack + off))
 #define SSPTRt(off,type)        ((type*) ((char*)PL_savestack + off))
 
-/* A jmpenv packages the state required to perform a proper non-local jump.
- * Note that there is a start_env initialized when perl starts, and top_env
- * points to this initially, so top_env should always be non-null.
- *
- * Existence of a non-null top_env->je_prev implies it is valid to call
- * longjmp() at that runlevel (we make sure start_env.je_prev is always
- * null to ensure this).
- *
- * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
- * establish a local jmpenv to handle exception traps.  Care must be taken
- * to restore the previous value of je_mustcatch before exiting the
- * stack frame iff JMPENV_PUSH was not called in that stack frame.
- * GSAR 97-03-27
- */
-
-struct jmpenv {
-    struct jmpenv *    je_prev;
-    Sigjmp_buf         je_buf;         /* only for use if !je_throw */
-    int                        je_ret;         /* last exception thrown */
-    bool               je_mustcatch;   /* need to call longjmp()? */
-};
-
-typedef struct jmpenv JMPENV;
-
-#ifdef OP_IN_REGISTER
-#define OP_REG_TO_MEM  PL_opsave = op
-#define OP_MEM_TO_REG  op = PL_opsave
-#else
-#define OP_REG_TO_MEM  NOOP
-#define OP_MEM_TO_REG  NOOP
-#endif
-
-/*
- * How to build the first jmpenv.
- *
- * top_env needs to be non-zero. It points to an area
- * in which longjmp() stuff is stored, as C callstack
- * info there at least is thread specific this has to
- * be per-thread. Otherwise a 'die' in a thread gives
- * that thread the C stack of last thread to do an eval {}!
- */
+#define save_freesv(op)                save_pushptr((void *)(op), SAVEt_FREESV)
+#define save_mortalizesv(op)   save_pushptr((void *)(op), SAVEt_MORTALIZESV)
 
-#define JMPENV_BOOTSTRAP \
-    STMT_START {                               \
-       Zero(&PL_start_env, 1, JMPENV);         \
-       PL_start_env.je_ret = -1;               \
-       PL_start_env.je_mustcatch = TRUE;       \
-       PL_top_env = &PL_start_env;             \
+# define save_freeop(op)                    \
+STMT_START {                                 \
+      OP * const _o = (OP *)(op);             \
+      assert(!_o->op_savefree);               \
+      _o->op_savefree = 1;                     \
+      save_pushptr((void *)(_o), SAVEt_FREEOP); \
     } STMT_END
+#define save_freepv(pv)                save_pushptr((void *)(pv), SAVEt_FREEPV)
+#define save_op()              save_pushptr((void *)(PL_op), SAVEt_OP)
 
 /*
- *   PERL_FLEXIBLE_EXCEPTIONS
- * 
- * All the flexible exceptions code has been removed.
- * See the following threads for details:
+ * Local variables:
+ * c-indentation-style: bsd
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
  *
- *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-07/msg00378.html
- * 
- * Joshua's original patches (which weren't applied) and discussion:
- * 
- *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01396.html
- *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01489.html
- *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01491.html
- *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01608.html
- *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02144.html
- *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02998.html
- * 
- * Chip's reworked patch and discussion:
- * 
- *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg00520.html
- * 
- * The flaw in these patches (which went unnoticed at the time) was
- * that they moved some code that could potentially die() out of the
- * region protected by the setjmp()s.  This caused exceptions within
- * END blocks and such to not be handled by the correct setjmp().
- * 
- * The original patches that introduces flexible exceptions were:
- *
- *   http://public.activestate.com/cgi-bin/perlbrowse?patch=3386
- *   http://public.activestate.com/cgi-bin/perlbrowse?patch=5162
+ * ex: set ts=8 sts=4 sw=4 et:
  */
-
-#define dJMPENV                JMPENV cur_env
-
-#define JMPENV_PUSH(v) \
-    STMT_START {                                                       \
-       DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p\n",     \
-                        &cur_env, PL_top_env));                        \
-       cur_env.je_prev = PL_top_env;                                   \
-       OP_REG_TO_MEM;                                                  \
-       cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK);              \
-       OP_MEM_TO_REG;                                                  \
-       PL_top_env = &cur_env;                                          \
-       cur_env.je_mustcatch = FALSE;                                   \
-       (v) = cur_env.je_ret;                                           \
-    } STMT_END
-
-#define JMPENV_POP \
-    STMT_START {                                                       \
-       DEBUG_l(Perl_deb(aTHX_ "popping jumplevel was %p, now %p\n",    \
-                        PL_top_env, cur_env.je_prev));                 \
-       PL_top_env = cur_env.je_prev;                                   \
-    } STMT_END
-
-#define JMPENV_JUMP(v) \
-    STMT_START {                                               \
-       OP_REG_TO_MEM;                                          \
-       if (PL_top_env->je_prev)                                \
-           PerlProc_longjmp(PL_top_env->je_buf, (v));          \
-       if ((v) == 2)                                           \
-           PerlProc_exit(STATUS_NATIVE_EXPORT);                \
-       PerlIO_printf(PerlIO_stderr(), "panic: top_env\n");     \
-       PerlProc_exit(1);                                       \
-    } STMT_END
-
-#define CATCH_GET              (PL_top_env->je_mustcatch)
-#define CATCH_SET(v)           (PL_top_env->je_mustcatch = (v))