Major rehacking and cleanup of sp_pcontext.

This finishes (almost) WL#2002: Implement stored procedure GOTO.
Only the syntax issue for free labels remains ("label L;" vs "L:").


include/mysqld_error.h:
  New error code for GOTO in SP handler.
mysql-test/r/sp-error.result:
  New error test cases for GOTO.
mysql-test/r/sp.result:
  New test cases for GOTO.
  Also removed some things that made it impossible to run the test in
  an external (debugged) mysqld.
mysql-test/t/sp-error.test:
  New error test cases for GOTO.
mysql-test/t/sp.test:
  New test cases for GOTO.
  Also removed some things that made it impossible to run the test in
  an external (debugged) mysqld.
sql/share/czech/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/danish/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/dutch/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/english/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/estonian/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/french/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/german/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/greek/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/hungarian/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/italian/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/japanese/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/korean/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/norwegian-ny/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/norwegian/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/polish/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/portuguese/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/romanian/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/russian/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/serbian/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/slovak/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/spanish/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/swedish/errmsg.txt:
  New error message for GOTO in SP handler.
sql/share/ukrainian/errmsg.txt:
  New error message for GOTO in SP handler.
sql/sp_head.cc:
  Code cleanup (renaming of pcontext methods), support goto, and fixed bug
  in jump shortcutting in the optimizer (detect infinite loops).
sql/sp_head.h:
  Code cleanup (renaming of pcontext methods), support goto, and fixed bug
  in jump shortcutting in the optimizer (detect infinite loops).
sql/sp_pcontext.cc:
  Major rehack and cleanup:
  - We now push and pop a chain of contexts during parsing (instead of having
    a single one).
  - Makes error detection for GOTO easier and enables some optmizations and
    debugger support.
  - Makes it a little trickier to keep track on variable and cursor indexes instead.
  - Renamed things to get a more consistent naming scheme too.
sql/sp_pcontext.h:
  Major rehack and cleanup:
  - We now push and pop a chain of contexts during parsing (instead of having
    a single one).
  - Makes error detection for GOTO easier and enables some optmizations and
    debugger support.
  - Makes it a little trickier to keep track on variable and cursor indexes instead.
  - Renamed things to get a more consistent naming scheme too.
sql/sql_yacc.yy:
  Changes to reflect the rework and renamings in sp_pcontext, and fixed
  some GOTO error checking.

28 files changed, 337 insertions, 353 deletions

diff --git a/sql/share/czech/errmsg.txt b/sql/share/czech/errmsg.txt
index 264bc38117a..9d1c429d5b6 100644
--- a/sql/share/czech/errmsg.txt
+++ b/sql/share/czech/errmsg.txt
@@ -369,3 +369,4 @@ character-set=latin2
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/danish/errmsg.txt b/sql/share/danish/errmsg.txt
index c0f915e0b53..b2d2fdf4d77 100644
--- a/sql/share/danish/errmsg.txt
+++ b/sql/share/danish/errmsg.txt
@@ -363,3 +363,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/dutch/errmsg.txt b/sql/share/dutch/errmsg.txt
index 9bfca16ad54..85c0443869f 100644
--- a/sql/share/dutch/errmsg.txt
+++ b/sql/share/dutch/errmsg.txt
@@ -371,3 +371,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/english/errmsg.txt b/sql/share/english/errmsg.txt
index c159e6b49c7..641f267d67e 100644
--- a/sql/share/english/errmsg.txt
+++ b/sql/share/english/errmsg.txt
@@ -360,3 +360,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/estonian/errmsg.txt b/sql/share/estonian/errmsg.txt
index 4c679a2967a..e64c0c17e74 100644
--- a/sql/share/estonian/errmsg.txt
+++ b/sql/share/estonian/errmsg.txt
@@ -365,3 +365,4 @@ character-set=latin7
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/french/errmsg.txt b/sql/share/french/errmsg.txt
index 2f8cccbc6fb..f3443457346 100644
--- a/sql/share/french/errmsg.txt
+++ b/sql/share/french/errmsg.txt
@@ -360,3 +360,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/german/errmsg.txt b/sql/share/german/errmsg.txt
index dc18cfa9b34..498a230faed 100644
--- a/sql/share/german/errmsg.txt
+++ b/sql/share/german/errmsg.txt
@@ -372,3 +372,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/greek/errmsg.txt b/sql/share/greek/errmsg.txt
index b8cbe9b5a75..2827517ba9a 100644
--- a/sql/share/greek/errmsg.txt
+++ b/sql/share/greek/errmsg.txt
@@ -360,3 +360,4 @@ character-set=greek
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/hungarian/errmsg.txt b/sql/share/hungarian/errmsg.txt
index b7cc9fe34d7..fab0b156322 100644
--- a/sql/share/hungarian/errmsg.txt
+++ b/sql/share/hungarian/errmsg.txt
@@ -362,3 +362,4 @@ character-set=latin2
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/italian/errmsg.txt b/sql/share/italian/errmsg.txt
index 0c9576cab47..24634514a23 100644
--- a/sql/share/italian/errmsg.txt
+++ b/sql/share/italian/errmsg.txt
@@ -360,3 +360,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/japanese/errmsg.txt b/sql/share/japanese/errmsg.txt
index d5ef9f22a56..68f2857aeca 100644
--- a/sql/share/japanese/errmsg.txt
+++ b/sql/share/japanese/errmsg.txt
@@ -362,3 +362,4 @@ character-set=ujis
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/korean/errmsg.txt b/sql/share/korean/errmsg.txt
index 4f03bedc717..70267c82364 100644
--- a/sql/share/korean/errmsg.txt
+++ b/sql/share/korean/errmsg.txt
@@ -360,3 +360,4 @@ character-set=euckr
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/norwegian-ny/errmsg.txt b/sql/share/norwegian-ny/errmsg.txt
index 821453e6119..1d84a3a5e5a 100644
--- a/sql/share/norwegian-ny/errmsg.txt
+++ b/sql/share/norwegian-ny/errmsg.txt
@@ -362,3 +362,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/norwegian/errmsg.txt b/sql/share/norwegian/errmsg.txt
index 5a60042b19e..be881d54473 100644
--- a/sql/share/norwegian/errmsg.txt
+++ b/sql/share/norwegian/errmsg.txt
@@ -362,3 +362,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/polish/errmsg.txt b/sql/share/polish/errmsg.txt
index 2f9f5b4bbce..8a576b5bf82 100644
--- a/sql/share/polish/errmsg.txt
+++ b/sql/share/polish/errmsg.txt
@@ -364,3 +364,4 @@ character-set=latin2
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/portuguese/errmsg.txt b/sql/share/portuguese/errmsg.txt
index 2a32c80138b..6794db726cc 100644
--- a/sql/share/portuguese/errmsg.txt
+++ b/sql/share/portuguese/errmsg.txt
@@ -361,3 +361,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/romanian/errmsg.txt b/sql/share/romanian/errmsg.txt
index 211a0072934..9eaa4860b64 100644
--- a/sql/share/romanian/errmsg.txt
+++ b/sql/share/romanian/errmsg.txt
@@ -364,3 +364,4 @@ character-set=latin2
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/russian/errmsg.txt b/sql/share/russian/errmsg.txt
index 907cece485f..eec85d611fc 100644
--- a/sql/share/russian/errmsg.txt
+++ b/sql/share/russian/errmsg.txt
@@ -362,3 +362,4 @@ character-set=koi8r
 "ïÂÎÏ×ÌÑÅÍÙÊ view ÎÅ ÓÏÄÅÒÖÉÔ ËÌÀÞÁ ÉÓÐÏÌØÚÏ×ÁÎÎÏÊ × ÎÅÍ ÔÁÂÌÉÃ(Ù)"
 "View '%-.64s.%-.64s' ÓÓÙÌÁÅÔÓÑ ÎÁ ÎÅÓÕÝÅÓÔ×ÕÀÝÉÅ ÔÁÂÌÉÃÙ ÉÌÉ ÓÌÏÌÂÃÙ"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/serbian/errmsg.txt b/sql/share/serbian/errmsg.txt
index 5b74999a3cd..4039268f446 100644
--- a/sql/share/serbian/errmsg.txt
+++ b/sql/share/serbian/errmsg.txt
@@ -366,3 +366,4 @@ character-set=cp1250
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/slovak/errmsg.txt b/sql/share/slovak/errmsg.txt
index 5d7fce940e2..9be5ce01d6a 100644
--- a/sql/share/slovak/errmsg.txt
+++ b/sql/share/slovak/errmsg.txt
@@ -368,3 +368,4 @@ character-set=latin2
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/spanish/errmsg.txt b/sql/share/spanish/errmsg.txt
index 570da612be9..dc15f8b8d5e 100644
--- a/sql/share/spanish/errmsg.txt
+++ b/sql/share/spanish/errmsg.txt
@@ -362,3 +362,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/swedish/errmsg.txt b/sql/share/swedish/errmsg.txt
index 4e97393b0b1..ee5436c3b80 100644
--- a/sql/share/swedish/errmsg.txt
+++ b/sql/share/swedish/errmsg.txt
@@ -360,3 +360,4 @@ character-set=latin1
 "View being updated does not have complete key of underlying table in it"
 "View '%-.64s.%-.64s' references invalid table(s) or column(s)"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/share/ukrainian/errmsg.txt b/sql/share/ukrainian/errmsg.txt
index a043b6eb651..cb1d99e2fec 100644
--- a/sql/share/ukrainian/errmsg.txt
+++ b/sql/share/ukrainian/errmsg.txt
@@ -365,3 +365,4 @@ character-set=koi8u
 "View, ÝÏ ÏÎÏ×ÌÀÅÔØÓÑ, ΊͦÓÔÉÔØ ÐÏ×ÎÏÇÏ ËÌÀÞÁ ÔÁÂÌÉæ(Ø), ÝÏ ×ÉËÏÒ¦ÓÔÁÎÁ × ÎØÀÏÍÕ"
 "View '%-.64s.%-.64s' ÐÏÓÉÌÁ¤ÔÓÑ ÎÁ ÎŦÓÎÕÀÞ¦ ÔÁÂÌÉæ ÁÂÏ ÓÔÏ×Âæ"
 "Can't drop a %s from within another stored routine"
+"GOTO is not allowed in a stored procedure handler"
diff --git a/sql/sp_head.cc b/sql/sp_head.cc
index 5a58c32d2da..fd95767b7cd 100644
--- a/sql/sp_head.cc
+++ b/sql/sp_head.cc
@@ -257,7 +257,7 @@ sp_head::operator delete(void *ptr, size_t size)
 
 sp_head::sp_head()
   :Item_arena((bool)FALSE), m_returns_cs(NULL), m_has_return(FALSE),
-   m_simple_case(FALSE), m_multi_results(FALSE)
+   m_simple_case(FALSE), m_multi_results(FALSE), m_in_handler(FALSE)
 {
   DBUG_ENTER("sp_head::sp_head");
 
@@ -272,7 +272,7 @@ sp_head::init(LEX *lex)
 {
   DBUG_ENTER("sp_head::init");
 
-  lex->spcont= m_pcont= new sp_pcontext();
+  lex->spcont= m_pcont= new sp_pcontext(NULL);
   my_init_dynamic_array(&m_instr, sizeof(sp_instr *), 16, 8);
   m_param_begin= m_param_end= m_returns_begin= m_returns_end= m_body_begin= 0;
   m_qname.str= m_db.str= m_name.str= m_params.str= m_retstr.str=
@@ -514,10 +514,10 @@ sp_head::execute_function(THD *thd, Item **argp, uint argcount, Item **resp)
 {
   DBUG_ENTER("sp_head::execute_function");
   DBUG_PRINT("info", ("function %s", m_name.str));
-  uint csize = m_pcont->max_framesize();
-  uint params = m_pcont->params();
-  uint hmax = m_pcont->handlers();
-  uint cmax = m_pcont->cursors();
+  uint csize = m_pcont->max_pvars();
+  uint params = m_pcont->current_pvars();
+  uint hmax = m_pcont->max_handlers();
+  uint cmax = m_pcont->max_cursors();
   sp_rcontext *octx = thd->spcont;
   sp_rcontext *nctx = NULL;
   uint i;
@@ -594,10 +594,10 @@ sp_head::execute_procedure(THD *thd, List<Item> *args)
   DBUG_ENTER("sp_head::execute_procedure");
   DBUG_PRINT("info", ("procedure %s", m_name.str));
   int ret= 0;
-  uint csize = m_pcont->max_framesize();
-  uint params = m_pcont->params();
-  uint hmax = m_pcont->handlers();
-  uint cmax = m_pcont->cursors();
+  uint csize = m_pcont->max_pvars();
+  uint params = m_pcont->current_pvars();
+  uint hmax = m_pcont->max_handlers();
+  uint cmax = m_pcont->max_cursors();
   sp_rcontext *octx = thd->spcont;
   sp_rcontext *nctx = NULL;
   my_bool tmp_octx = FALSE;	// True if we have allocated a temporary octx
@@ -851,12 +851,18 @@ sp_head::backpatch(sp_label_t *lab)
 	(bp->lab->type == SP_LAB_REF &&
 	 my_strcasecmp(system_charset_info, bp->lab->name, lab->name) == 0))
     {
-      sp_scope_t sdiff;
+      if (bp->lab->type != SP_LAB_REF)
+	bp->instr->backpatch(dest, lab->ctx);
+      else
+      {
+	sp_label_t *dstlab= bp->lab->ctx->find_label(lab->name);
 
-      if (bp->lab->type == SP_LAB_REF)
-	bp->lab= lab;
-      m_pcont->diff_scopes(0, &sdiff);
-      bp->instr->backpatch(dest, sdiff.hndlrs, sdiff.curs);
+	if (dstlab)
+	{
+	  bp->lab= lab;
+	  bp->instr->backpatch(dest, dstlab->ctx);
+	}
+      }
     }
   }
 }
@@ -1236,7 +1242,7 @@ sp_instr_jump::print(String *str)
 uint
 sp_instr_jump::opt_mark(sp_head *sp)
 {
-  m_dest= opt_shortcut_jump(sp);
+  m_dest= opt_shortcut_jump(sp, this);
   if (m_dest != m_ip+1)		/* Jumping to following instruction? */
     marked= 1;
   m_optdest= sp->get_instr(m_dest);
@@ -1244,15 +1250,18 @@ sp_instr_jump::opt_mark(sp_head *sp)
 }
 
 uint
-sp_instr_jump::opt_shortcut_jump(sp_head *sp)
+sp_instr_jump::opt_shortcut_jump(sp_head *sp, sp_instr *start)
 {
   uint dest= m_dest;
   sp_instr *i;
 
   while ((i= sp->get_instr(dest)))
   {
-    uint ndest= i->opt_shortcut_jump(sp);
+    uint ndest;
 
+    if (start == i)
+      break;
+    ndest= i->opt_shortcut_jump(sp, start);
     if (ndest == dest)
       break;
     dest= ndest;
@@ -1320,7 +1329,7 @@ sp_instr_jump_if::opt_mark(sp_head *sp)
   marked= 1;
   if ((i= sp->get_instr(m_dest)))
   {
-    m_dest= i->opt_shortcut_jump(sp);
+    m_dest= i->opt_shortcut_jump(sp, this);
     m_optdest= sp->get_instr(m_dest);
   }
   sp->opt_mark(m_dest);
@@ -1377,7 +1386,7 @@ sp_instr_jump_if_not::opt_mark(sp_head *sp)
   marked= 1;
   if ((i= sp->get_instr(m_dest)))
   {
-    m_dest= i->opt_shortcut_jump(sp);
+    m_dest= i->opt_shortcut_jump(sp, this);
     m_optdest= sp->get_instr(m_dest);
   }
   sp->opt_mark(m_dest);
@@ -1460,7 +1469,7 @@ sp_instr_hpush_jump::opt_mark(sp_head *sp)
   marked= 1;
   if ((i= sp->get_instr(m_dest)))
   {
-    m_dest= i->opt_shortcut_jump(sp);
+    m_dest= i->opt_shortcut_jump(sp, this);
     m_optdest= sp->get_instr(m_dest);
   }
   sp->opt_mark(m_dest);
@@ -1487,6 +1496,13 @@ sp_instr_hpop::print(String *str)
   str->qs_append(m_count);
 }
 
+void
+sp_instr_hpop::backpatch(uint dest, sp_pcontext *dst_ctx)
+{
+  m_count= m_ctx->diff_handlers(dst_ctx);
+}
+
+
 //
 // sp_instr_hreturn
 //
@@ -1551,6 +1567,12 @@ sp_instr_cpop::print(String *str)
   str->qs_append(m_count);
 }
 
+void
+sp_instr_cpop::backpatch(uint dest, sp_pcontext *dst_ctx)
+{
+  m_count= m_ctx->diff_cursors(dst_ctx);
+}
+
 //
 // sp_instr_copen
 //
diff --git a/sql/sp_head.h b/sql/sp_head.h
index 9c29297180d..c0881661ad1 100644
--- a/sql/sp_head.h
+++ b/sql/sp_head.h
@@ -86,6 +86,7 @@ public:
   my_bool m_has_return;		// For FUNCTIONs only
   my_bool m_simple_case;	// TRUE if parsing simple case, FALSE otherwise
   my_bool m_multi_results;	// TRUE if a procedure with SELECT(s)
+  my_bool m_in_handler;		// TRUE if parser in a handler body
   uint m_old_cmq;		// Old CLIENT_MULTI_QUERIES value
   st_sp_chistics *m_chistics;
   ulong m_sql_mode;		// For SHOW CREATE
@@ -262,10 +263,11 @@ public:
   uint marked;
   Item *free_list;              // My Items
   uint m_ip;			// My index
+  sp_pcontext *m_ctx;		// My parse context
 
   // Should give each a name or type code for debugging purposes?
-  sp_instr(uint ip)
-    :Sql_alloc(), marked(0), free_list(0), m_ip(ip)
+  sp_instr(uint ip, sp_pcontext *ctx)
+    :Sql_alloc(), marked(0), free_list(0), m_ip(ip), m_ctx(ctx)
   {}
 
   virtual ~sp_instr()
@@ -279,7 +281,7 @@ public:
 
   virtual void print(String *str) = 0;
 
-  virtual void backpatch(uint dest, uint hpop, uint cpop)
+  virtual void backpatch(uint dest, sp_pcontext *dst_ctx)
   {}
 
   virtual uint opt_mark(sp_head *sp)
@@ -288,7 +290,7 @@ public:
     return m_ip+1;
   }
 
-  virtual uint opt_shortcut_jump(sp_head *sp)
+  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
   {
     return m_ip;
   }
@@ -311,8 +313,8 @@ class sp_instr_stmt : public sp_instr
 
 public:
 
-  sp_instr_stmt(uint ip)
-    : sp_instr(ip), m_lex(NULL)
+  sp_instr_stmt(uint ip, sp_pcontext *ctx)
+    : sp_instr(ip, ctx), m_lex(NULL)
   {}
 
   virtual ~sp_instr_stmt();
@@ -353,8 +355,10 @@ public:
 
   TABLE_LIST *tables;
 
-  sp_instr_set(uint ip, uint offset, Item *val, enum enum_field_types type)
-    : sp_instr(ip), tables(NULL), m_offset(offset), m_value(val), m_type(type)
+  sp_instr_set(uint ip, sp_pcontext *ctx,
+	       uint offset, Item *val, enum enum_field_types type)
+    : sp_instr(ip, ctx),
+      tables(NULL), m_offset(offset), m_value(val), m_type(type)
   {}
 
   virtual ~sp_instr_set()
@@ -382,12 +386,12 @@ public:
 
   uint m_dest;			// Where we will go
 
-  sp_instr_jump(uint ip)
-    : sp_instr(ip), m_dest(0), m_optdest(0)
+  sp_instr_jump(uint ip, sp_pcontext *ctx)
+    : sp_instr(ip, ctx), m_dest(0), m_optdest(0)
   {}
 
-  sp_instr_jump(uint ip, uint dest)
-    : sp_instr(ip), m_dest(dest), m_optdest(0)
+  sp_instr_jump(uint ip, sp_pcontext *ctx, uint dest)
+    : sp_instr(ip, ctx), m_dest(dest), m_optdest(0)
   {}
 
   virtual ~sp_instr_jump()
@@ -399,11 +403,11 @@ public:
 
   virtual uint opt_mark(sp_head *sp);
 
-  virtual uint opt_shortcut_jump(sp_head *sp);
+  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start);
 
   virtual void opt_move(uint dst, List<sp_instr> *ibp);
 
-  virtual void backpatch(uint dest, uint hpop, uint cpop)
+  virtual void backpatch(uint dest, sp_pcontext *dst_ctx)
   {
     if (m_dest == 0)		// Don't reset
       m_dest= dest;
@@ -425,12 +429,12 @@ public:
 
   TABLE_LIST *tables;
 
-  sp_instr_jump_if(uint ip, Item *i)
-    : sp_instr_jump(ip), tables(NULL), m_expr(i)
+  sp_instr_jump_if(uint ip, sp_pcontext *ctx, Item *i)
+    : sp_instr_jump(ip, ctx), tables(NULL), m_expr(i)
   {}
 
-  sp_instr_jump_if(uint ip, Item *i, uint dest)
-    : sp_instr_jump(ip, dest), tables(NULL), m_expr(i)
+  sp_instr_jump_if(uint ip, sp_pcontext *ctx, Item *i, uint dest)
+    : sp_instr_jump(ip, ctx, dest), tables(NULL), m_expr(i)
   {}
 
   virtual ~sp_instr_jump_if()
@@ -442,7 +446,7 @@ public:
 
   virtual uint opt_mark(sp_head *sp);
 
-  virtual uint opt_shortcut_jump(sp_head *sp)
+  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
   {
     return m_ip;
   }
@@ -463,12 +467,12 @@ public:
 
   TABLE_LIST *tables;
 
-  sp_instr_jump_if_not(uint ip, Item *i)
-    : sp_instr_jump(ip), tables(NULL), m_expr(i)
+  sp_instr_jump_if_not(uint ip, sp_pcontext *ctx, Item *i)
+    : sp_instr_jump(ip, ctx), tables(NULL), m_expr(i)
   {}
 
-  sp_instr_jump_if_not(uint ip, Item *i, uint dest)
-    : sp_instr_jump(ip, dest), tables(NULL), m_expr(i)
+  sp_instr_jump_if_not(uint ip, sp_pcontext *ctx, Item *i, uint dest)
+    : sp_instr_jump(ip, ctx, dest), tables(NULL), m_expr(i)
   {}
 
   virtual ~sp_instr_jump_if_not()
@@ -480,7 +484,7 @@ public:
 
   virtual uint opt_mark(sp_head *sp);
 
-  virtual uint opt_shortcut_jump(sp_head *sp)
+  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
   {
     return m_ip;
   }
@@ -501,8 +505,9 @@ public:
 
   TABLE_LIST *tables;
 
-  sp_instr_freturn(uint ip, Item *val, enum enum_field_types type)
-    : sp_instr(ip), tables(NULL), m_value(val), m_type(type)
+  sp_instr_freturn(uint ip, sp_pcontext *ctx,
+		   Item *val, enum enum_field_types type)
+    : sp_instr(ip, ctx), tables(NULL), m_value(val), m_type(type)
   {}
 
   virtual ~sp_instr_freturn()
@@ -533,8 +538,8 @@ class sp_instr_hpush_jump : public sp_instr_jump
 
 public:
 
-  sp_instr_hpush_jump(uint ip, int htype, uint fp)
-    : sp_instr_jump(ip), m_type(htype), m_frame(fp)
+  sp_instr_hpush_jump(uint ip, sp_pcontext *ctx, int htype, uint fp)
+    : sp_instr_jump(ip, ctx), m_type(htype), m_frame(fp)
   {
     m_handler= ip+1;
     m_cond.empty();
@@ -551,7 +556,7 @@ public:
 
   virtual uint opt_mark(sp_head *sp);
 
-  virtual uint opt_shortcut_jump(sp_head *sp)
+  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
   {
     return m_ip;
   }
@@ -578,8 +583,8 @@ class sp_instr_hpop : public sp_instr
 
 public:
 
-  sp_instr_hpop(uint ip, uint count)
-    : sp_instr(ip), m_count(count)
+  sp_instr_hpop(uint ip, sp_pcontext *ctx, uint count)
+    : sp_instr(ip, ctx), m_count(count)
   {}
 
   virtual ~sp_instr_hpop()
@@ -589,13 +594,7 @@ public:
 
   virtual void print(String *str);
 
-  virtual void backpatch(uint dest, uint hpop, uint cpop)
-  {
-    if (hpop > m_count)
-      m_count= 0;
-    else
-      m_count-= hpop;
-  }
+  virtual void backpatch(uint dest, sp_pcontext *dst_ctx);
 
   virtual uint opt_mark(sp_head *sp)
   {
@@ -618,8 +617,8 @@ class sp_instr_hreturn : public sp_instr
 
 public:
 
-  sp_instr_hreturn(uint ip, uint fp)
-    : sp_instr(ip), m_frame(fp)
+  sp_instr_hreturn(uint ip, sp_pcontext *ctx, uint fp)
+    : sp_instr(ip, ctx), m_frame(fp)
   {}
 
   virtual ~sp_instr_hreturn()
@@ -649,8 +648,8 @@ class sp_instr_cpush : public sp_instr
 
 public:
 
-  sp_instr_cpush(uint ip, LEX *lex)
-    : sp_instr(ip), m_lex(lex)
+  sp_instr_cpush(uint ip, sp_pcontext *ctx, LEX *lex)
+    : sp_instr(ip, ctx), m_lex(lex)
   {}
 
   virtual ~sp_instr_cpush();
@@ -673,8 +672,8 @@ class sp_instr_cpop : public sp_instr
 
 public:
 
-  sp_instr_cpop(uint ip, uint count)
-    : sp_instr(ip), m_count(count)
+  sp_instr_cpop(uint ip, sp_pcontext *ctx, uint count)
+    : sp_instr(ip, ctx), m_count(count)
   {}
 
   virtual ~sp_instr_cpop()
@@ -684,13 +683,7 @@ public:
 
   virtual void print(String *str);
 
-  virtual void backpatch(uint dest, uint hpop, uint cpop)
-  {
-    if (cpop > m_count)
-      m_count= 0;
-    else
-      m_count-= cpop;
-  }
+  virtual void backpatch(uint dest, sp_pcontext *dst_ctx);
 
   virtual uint opt_mark(sp_head *sp)
   {
@@ -713,8 +706,8 @@ class sp_instr_copen : public sp_instr_stmt
 
 public:
 
-  sp_instr_copen(uint ip, uint c)
-    : sp_instr_stmt(ip), m_cursor(c)
+  sp_instr_copen(uint ip, sp_pcontext *ctx, uint c)
+    : sp_instr_stmt(ip, ctx), m_cursor(c)
   {}
 
   virtual ~sp_instr_copen()
@@ -738,8 +731,8 @@ class sp_instr_cclose : public sp_instr
 
 public:
 
-  sp_instr_cclose(uint ip, uint c)
-    : sp_instr(ip), m_cursor(c)
+  sp_instr_cclose(uint ip, sp_pcontext *ctx, uint c)
+    : sp_instr(ip, ctx), m_cursor(c)
   {}
 
   virtual ~sp_instr_cclose()
@@ -763,8 +756,8 @@ class sp_instr_cfetch : public sp_instr
 
 public:
 
-  sp_instr_cfetch(uint ip, uint c)
-    : sp_instr(ip), m_cursor(c)
+  sp_instr_cfetch(uint ip, sp_pcontext *ctx, uint c)
+    : sp_instr(ip, ctx), m_cursor(c)
   {
     m_varlist.empty();
   }
@@ -796,8 +789,8 @@ class sp_instr_error : public sp_instr
 
 public:
 
-  sp_instr_error(uint ip, int errcode)
-    : sp_instr(ip), m_errcode(errcode)
+  sp_instr_error(uint ip, sp_pcontext *ctx, int errcode)
+    : sp_instr(ip, ctx), m_errcode(errcode)
   {}
 
   virtual ~sp_instr_error()
diff --git a/sql/sp_pcontext.cc b/sql/sp_pcontext.cc
index 6f999531e58..c83259c3926 100644
--- a/sql/sp_pcontext.cc
+++ b/sql/sp_pcontext.cc
@@ -26,79 +26,98 @@
 #include "sp_pcontext.h"
 #include "sp_head.h"
 
-sp_pcontext::sp_pcontext()
-  : Sql_alloc(), m_params(0), m_framesize(0), m_handlers(0), m_cursmax(0),
-    m_hndlrlev(0)
+sp_pcontext::sp_pcontext(sp_pcontext *prev)
+  : Sql_alloc(), m_psubsize(0), m_csubsize(0), m_hsubsize(0),
+    m_parent(prev), m_handlers(0)
 {
   VOID(my_init_dynamic_array(&m_pvar, sizeof(sp_pvar_t *), 16, 8));
   VOID(my_init_dynamic_array(&m_cond, sizeof(sp_cond_type_t *), 16, 8));
   VOID(my_init_dynamic_array(&m_cursor, sizeof(LEX_STRING), 16, 8));
-  VOID(my_init_dynamic_array(&m_scopes, sizeof(sp_scope_t), 16, 8));
-  VOID(my_init_dynamic_array(&m_glabel, sizeof(sp_label_t *), 16, 8));
   m_label.empty();
+  m_children.empty();
+  if (!prev)
+    m_poffset= m_coffset= 0;
+  else
+  {
+    m_poffset= prev->current_pvars();
+    m_coffset= prev->current_cursors();
+  }
 }
 
 void
 sp_pcontext::destroy()
 {
+  List_iterator_fast<sp_pcontext> li(m_children);
+  sp_pcontext *child;
+
+  while ((child= li++))
+    child->destroy();
+
+  m_children.empty();
+  m_label.empty();
   delete_dynamic(&m_pvar);
   delete_dynamic(&m_cond);
   delete_dynamic(&m_cursor);
-  delete_dynamic(&m_scopes);
-  delete_dynamic(&m_glabel);
-  m_label.empty();
 }
 
-void
-sp_pcontext::push_scope()
+sp_pcontext *
+sp_pcontext::push_context()
 {
-  sp_scope_t s;
-
-  s.vars= m_pvar.elements;
-  s.conds= m_cond.elements;
-  s.hndlrs= m_hndlrlev;
-  s.curs= m_cursor.elements;
-  s.glab= m_glabel.elements;
-  insert_dynamic(&m_scopes, (gptr)&s);
+  sp_pcontext *child= new sp_pcontext(this);
+
+  if (child)
+    m_children.push_back(child);
+  return child;
 }
 
-void
-sp_pcontext::pop_scope(sp_scope_t *sp)
+sp_pcontext *
+sp_pcontext::pop_context()
 {
-  byte *p= pop_dynamic(&m_scopes);
-
-  if (sp && p)
-    memcpy(sp, p, sizeof(sp_scope_t));
+  uint submax= max_pvars();
+
+  if (submax > m_parent->m_psubsize)
+    m_parent->m_psubsize= submax;
+  submax= max_handlers();
+  if (submax > m_parent->m_hsubsize)
+    m_parent->m_hsubsize= submax;
+  submax= max_cursors();
+  if (submax > m_parent->m_csubsize)
+    m_parent->m_csubsize= submax;
+  return m_parent;
 }
 
-void
-sp_pcontext::diff_scopes(uint sold, sp_scope_t *diffs)
+uint
+sp_pcontext::diff_handlers(sp_pcontext *ctx)
 {
-  uint snew= m_scopes.elements;
-  sp_scope_t scope;
+  uint n= 0;
+  sp_pcontext *pctx= this;
 
-  diffs->vars= diffs->conds= diffs->hndlrs= diffs->curs= diffs->glab= 0;
-  while (snew-- > sold)
+  while (pctx && pctx != ctx)
   {
-    get_dynamic(&m_scopes, (gptr)&scope, snew);
-    diffs->vars+= scope.vars;
-    diffs->conds+= scope.conds;
-    diffs->hndlrs+= scope.hndlrs;
-    diffs->curs+= scope.curs;
-    diffs->glab+= scope.glab;
+    n+= pctx->max_handlers();
+    pctx= pctx->parent_context();
   }
-  if (sold)
+  if (pctx)
+    return n;
+  return 0;			// Didn't find ctx
+}
+
+uint
+sp_pcontext::diff_cursors(sp_pcontext *ctx)
+{
+  uint n= 0;
+  sp_pcontext *pctx= this;
+
+  while (pctx && pctx != ctx)
   {
-    get_dynamic(&m_scopes, (gptr)&scope, sold-1);
-    diffs->vars-= scope.vars;
-    diffs->conds-= scope.conds;
-    diffs->hndlrs-= scope.hndlrs;
-    diffs->curs-= scope.curs;
-    diffs->glab-= scope.glab;
+    n+= pctx->max_cursors();
+    pctx= pctx->parent_context();
   }
+  if (pctx)
+    return n;
+  return 0;			// Didn't find ctx
 }
 
-
 /* This does a linear search (from newer to older variables, in case
 ** we have shadowed names).
 ** It's possible to have a more efficient allocation and search method,
@@ -109,20 +128,9 @@ sp_pcontext::diff_scopes(uint sold, sp_scope_t *diffs)
 sp_pvar_t *
 sp_pcontext::find_pvar(LEX_STRING *name, my_bool scoped)
 {
-  uint i = m_pvar.elements;
-  uint limit;
-
-  if (! scoped || m_scopes.elements == 0)
-    limit= 0;
-  else
-  {
-    sp_scope_t s;
+  uint i= m_pvar.elements;
 
-    get_dynamic(&m_scopes, (gptr)&s, m_scopes.elements-1);
-    limit= s.vars;
-  }
-      
-  while (i-- > limit)
+  while (i--)
   {
     sp_pvar_t *p;
 
@@ -134,6 +142,8 @@ sp_pcontext::find_pvar(LEX_STRING *name, my_bool scoped)
       return p;
     }
   }
+  if (!scoped && m_parent)
+    return m_parent->find_pvar(name, scoped);
   return NULL;
 }
 
@@ -145,13 +155,13 @@ sp_pcontext::push_pvar(LEX_STRING *name, enum enum_field_types type,
 
   if (p)
   {
-    if (m_pvar.elements == m_framesize)
-      m_framesize += 1;
+    if (m_pvar.elements == m_psubsize)
+      m_psubsize+= 1;
     p->name.str= name->str;
     p->name.length= name->length;
     p->type= type;
     p->mode= mode;
-    p->offset= m_pvar.elements;
+    p->offset= current_pvars();
     p->isset= (mode == sp_param_out ? FALSE : TRUE);
     p->dflt= NULL;
     insert_dynamic(&m_pvar, (gptr)&p);
@@ -168,7 +178,7 @@ sp_pcontext::push_label(char *name, uint ip)
     lab->name= name;
     lab->ip= ip;
     lab->type= SP_LAB_GOTO;
-    lab->scopes= 0;
+    lab->ctx= this;
     m_label.push_front(lab);
   }
   return lab;
@@ -184,6 +194,8 @@ sp_pcontext::find_label(char *name)
     if (my_strcasecmp(system_charset_info, name, lab->name) == 0)
       return lab;
 
+  if (m_parent)
+    return m_parent->find_label(name);
   return NULL;
 }
 
@@ -207,20 +219,9 @@ sp_pcontext::push_cond(LEX_STRING *name, sp_cond_type_t *val)
 sp_cond_type_t *
 sp_pcontext::find_cond(LEX_STRING *name, my_bool scoped)
 {
-  uint i = m_cond.elements;
-  uint limit;
+  uint i= m_cond.elements;
 
-  if (! scoped || m_scopes.elements == 0)
-    limit= 0;
-  else
-  {
-    sp_scope_t s;
-
-    get_dynamic(&m_scopes, (gptr)&s, m_scopes.elements-1);
-    limit= s.conds;
-  }
-      
-  while (i-- > limit)
+  while (i--)
   {
     sp_cond_t *p;
 
@@ -232,6 +233,8 @@ sp_pcontext::find_cond(LEX_STRING *name, my_bool scoped)
       return p->val;
     }
   }
+  if (!scoped && m_parent)
+    return m_parent->find_cond(name, scoped);
   return NULL;
 }
 
@@ -240,11 +243,11 @@ sp_pcontext::push_cursor(LEX_STRING *name)
 {
   LEX_STRING n;
 
+  if (m_cursor.elements == m_csubsize)
+    m_csubsize+= 1;
   n.str= name->str;
   n.length= name->length;
   insert_dynamic(&m_cursor, (gptr)&n);
-  if (m_cursor.elements > m_cursmax)
-    m_cursmax= m_cursor.elements;
 }
 
 /*
@@ -253,20 +256,9 @@ sp_pcontext::push_cursor(LEX_STRING *name)
 my_bool
 sp_pcontext::find_cursor(LEX_STRING *name, uint *poff, my_bool scoped)
 {
-  uint i = m_cursor.elements;
-  uint limit;
+  uint i= m_cursor.elements;
 
-  if (! scoped || m_scopes.elements == 0)
-    limit= 0;
-  else
-  {
-    sp_scope_t s;
-
-    get_dynamic(&m_scopes, (gptr)&s, m_scopes.elements-1);
-    limit= s.curs;
-  }
-      
-  while (i-- > limit)
+  while (i--)
   {
     LEX_STRING n;
 
@@ -279,43 +271,7 @@ sp_pcontext::find_cursor(LEX_STRING *name, uint *poff, my_bool scoped)
       return TRUE;
     }
   }
+  if (!scoped && m_parent)
+    return m_parent->find_cursor(name, poff, scoped);
   return FALSE;
 }
-
-sp_label_t *
-sp_pcontext::push_glabel(char *name, uint ip)
-{
-  sp_label_t *lab = (sp_label_t *)sql_alloc(sizeof(sp_label_t));
-
-  if (lab)
-  {
-    lab->name= name;
-    lab->ip= ip;
-    lab->type= SP_LAB_GOTO;
-    lab->scopes= 0;
-    insert_dynamic(&m_glabel, (gptr)&lab);
-  }
-  return lab;
-}
-
-sp_label_t *
-sp_pcontext::find_glabel(char *name)
-{
-  uint i= m_glabel.elements;
-
-  while (i--)
-  {
-    sp_label_t *lab;
-
-    get_dynamic(&m_glabel, (gptr)&lab, i);
-    if (my_strcasecmp(system_charset_info, name, lab->name) == 0)
-      return lab;
-  }
-  return NULL;
-}
-
-void
-sp_pcontext::pop_glabel(uint count)
-{
-  (void)pop_dynamic(&m_glabel);  
-}
diff --git a/sql/sp_pcontext.h b/sql/sp_pcontext.h
index e3bdc41779a..6db62614aa5 100644
--- a/sql/sp_pcontext.h
+++ b/sql/sp_pcontext.h
@@ -50,7 +50,7 @@ typedef struct sp_label
   char *name;
   uint ip;			// Instruction index
   int type;			// begin/iter or ref/free 
-  uint scopes;			// No. of scopes at label
+  struct sp_pcontext *ctx;	// The label's context
 } sp_label_t;
 
 typedef struct sp_cond_type
@@ -66,11 +66,6 @@ typedef struct sp_cond
   sp_cond_type_t *val;
 } sp_cond_t;
 
-typedef struct sp_scope
-{
-  uint vars, conds, hndlrs, curs, glab;
-} sp_scope_t;
-
 class sp_pcontext : public Sql_alloc
 {
   sp_pcontext(const sp_pcontext &); /* Prevent use of these */
@@ -78,28 +73,30 @@ class sp_pcontext : public Sql_alloc
 
  public:
 
-  sp_pcontext();
+  sp_pcontext(sp_pcontext *prev);
 
   // Free memory
   void
   destroy();
 
-  // For error checking of duplicate things
-  void
-  push_scope();
+  sp_pcontext *
+  push_context();
 
-  void
-  pop_scope(sp_scope_t *sp = 0);
+  // Returns the previous context, not the one we pop
+  sp_pcontext *
+  pop_context();
 
-  uint
-  scopes()
+  sp_pcontext *
+  parent_context()
   {
-    return m_scopes.elements;
+    return m_parent;
   }
 
-  // Sets '*diffs' to the differences between current scope index snew and sold
-  void
-  diff_scopes(uint sold, sp_scope_t *diffs);
+  uint
+  diff_handlers(sp_pcontext *ctx);
+
+  uint
+  diff_cursors(sp_pcontext *ctx);
 
 
   //
@@ -107,28 +104,27 @@ class sp_pcontext : public Sql_alloc
   //
 
   inline uint
-  max_framesize()
+  max_pvars()
   {
-    return m_framesize;
+    return m_psubsize + m_pvar.elements;
   }
 
   inline uint
-  current_framesize()
+  current_pvars()
   {
-    return m_pvar.elements;
+    return m_poffset + m_pvar.elements;
   }
 
   inline uint
-  params()
+  context_pvars()
   {
-    return m_params;
+    return m_pvar.elements;
   }
 
-  // Set the number of parameters to the current esize
-  inline void
-  set_params()
+  inline uint
+  pvar_context2index(uint i)
   {
-    m_params= m_pvar.elements;
+    return m_poffset + i;
   }
 
   inline void
@@ -199,7 +195,11 @@ class sp_pcontext : public Sql_alloc
   inline sp_label_t *
   last_label()
   {
-    return m_label.head();
+    sp_label_t *lab= m_label.head();
+
+    if (!lab && m_parent)
+      lab= m_parent->last_label();
+    return lab;
   }
 
   inline sp_label_t *
@@ -236,23 +236,17 @@ class sp_pcontext : public Sql_alloc
   }
 
   inline uint
-  handlers()
+  max_handlers()
   {
-    return m_handlers;
+    return m_hsubsize + m_handlers;
   }
 
   inline void
-  push_handlers(uint count)
+  push_handlers(uint n)
   {
-    m_hndlrlev+= count;
+    m_handlers+= n;
   }
 
-  inline void
-  pop_handlers(uint count)
-  {
-    m_hndlrlev-= count;
-  }
-  
   //
   // Cursors
   //
@@ -263,48 +257,41 @@ class sp_pcontext : public Sql_alloc
   my_bool
   find_cursor(LEX_STRING *name, uint *poff, my_bool scoped=0);
 
-  inline void
-  pop_cursor(uint num)
+  inline uint
+  max_cursors()
   {
-    while (num--)
-      pop_dynamic(&m_cursor);
+    return m_csubsize + m_cursor.elements;
   }
 
   inline uint
-  cursors()
+  current_cursors()
   {
-    return m_cursmax;
+    return m_coffset + m_cursor.elements;
   }
 
-  //
-  // GOTO labels
-  //
-
-  sp_label_t *
-  push_glabel(char *name, uint ip);
+protected:
 
-  sp_label_t *
-  find_glabel(char *name);
-
-  void
-  pop_glabel(uint count);
+  // The maximum sub context's framesizes
+  uint m_psubsize;		
+  uint m_csubsize;
+  uint m_hsubsize;
 
 private:
 
-  uint m_params;		// The number of parameters
-  uint m_framesize;		// The maximum framesize
-  uint m_handlers;		// The total number of handlers
-  uint m_cursmax;		// The maximum number of cursors
-  uint m_hndlrlev;		// Current number of active handlers
+  sp_pcontext *m_parent;	// Parent context
+
+  uint m_poffset;		// Variable offset for this context
+  uint m_coffset;		// Cursor offset for this context
+  uint m_handlers;		// No. of handlers in this context
 
   DYNAMIC_ARRAY m_pvar;		// Parameters/variables
   DYNAMIC_ARRAY m_cond;		// Conditions
   DYNAMIC_ARRAY m_cursor;	// Cursors
-  DYNAMIC_ARRAY m_scopes;	// For error checking
-  DYNAMIC_ARRAY m_glabel;	// Goto labels
 
   List<sp_label_t> m_label;	// The label list
 
+  List<sp_pcontext> m_children;	// Children contexts, used for destruction
+
 }; // class sp_pcontext : public Sql_alloc
 
 
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index a01abd9141b..1b15bc9a516 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -1169,7 +1169,6 @@ create:
 	    LEX *lex= Lex;
 
 	    lex->sphead->m_param_end= lex->tok_start;
-	    lex->spcont->set_params();
 	    bzero((char *)&lex->sp_chistics, sizeof(st_sp_chistics));
 	  }
 	  sp_c_chistics
@@ -1258,7 +1257,6 @@ create_function_tail:
 	  {
 	    LEX *lex= Lex;
 
-	    lex->spcont->set_params();
 	    lex->sphead->m_param_end= lex->tok_start;
 	  }
 	  RETURNS_SYM
@@ -1470,25 +1468,28 @@ sp_decl:
 	  DECLARE_SYM sp_decl_idents type sp_opt_default
 	  {
 	    LEX *lex= Lex;
-	    uint max= lex->spcont->current_framesize();
+	    sp_pcontext *ctx= lex->spcont;
+	    uint max= ctx->context_pvars();
 	    enum enum_field_types type= (enum enum_field_types)$3;
 	    Item *it= $4;
 
 	    for (uint i = max-$2 ; i < max ; i++)
 	    {
-	      lex->spcont->set_type(i, type);
+	      ctx->set_type(i, type);
 	      if (! it)
-	        lex->spcont->set_isset(i, FALSE);
+	        ctx->set_isset(i, FALSE);
 	      else
 	      {
 	        sp_instr_set *in= new sp_instr_set(lex->sphead->instructions(),
-	                                           i, it, type);
+	                                           ctx,
+						   ctx->pvar_context2index(i),
+						   it, type);
 
 		in->tables= lex->query_tables;
 		lex->query_tables= 0;
 	        lex->sphead->add_instr(in);
-	        lex->spcont->set_isset(i, TRUE);
-		lex->spcont->set_default(i, it);
+	        ctx->set_isset(i, TRUE);
+		ctx->set_default(i, it);
 	      }
 	    }
 	    $$.vars= $2;
@@ -1514,30 +1515,33 @@ sp_decl:
 	    sp_head *sp= lex->sphead;
 	    sp_pcontext *ctx= lex->spcont;
 	    sp_instr_hpush_jump *i=
-              new sp_instr_hpush_jump(sp->instructions(), $2,
-	                              ctx->current_framesize());
+              new sp_instr_hpush_jump(sp->instructions(), ctx, $2,
+	                              ctx->current_pvars());
 
 	    sp->add_instr(i);
 	    sp->push_backpatch(i, ctx->push_label((char *)"", 0));
 	    ctx->add_handler();
+	    sp->m_in_handler= TRUE;
 	  }
 	  sp_hcond_list sp_proc_stmt
 	  {
 	    LEX *lex= Lex;
 	    sp_head *sp= lex->sphead;
+	    sp_pcontext *ctx= lex->spcont;
 	    sp_label_t *hlab= lex->spcont->pop_label(); /* After this hdlr */
 
 	    if ($2 == SP_HANDLER_CONTINUE)
-	      sp->add_instr(new sp_instr_hreturn(sp->instructions(),
-	                                         lex->spcont->current_framesize()));
+	      sp->add_instr(new sp_instr_hreturn(sp->instructions(), ctx,
+	                                         ctx->current_pvars()));
 	    else
 	    {  /* EXIT or UNDO handler, just jump to the end of the block */
-	      sp_instr_jump *i= new sp_instr_jump(sp->instructions());
+	      sp_instr_jump *i= new sp_instr_jump(sp->instructions(), ctx);
 
 	      sp->add_instr(i);
 	      sp->push_backpatch(i, lex->spcont->last_label()); /* Block end */
 	    }
 	    lex->sphead->backpatch(hlab);
+	    sp->m_in_handler= FALSE;
 	    $$.vars= $$.conds= $$.curs= 0;
 	    $$.hndlrs= $6;
 	  }
@@ -1545,19 +1549,19 @@ sp_decl:
 	  {
 	    LEX *lex= Lex;
 	    sp_head *sp= lex->sphead;
-	    sp_pcontext *spc= lex->spcont;
+	    sp_pcontext *ctx= lex->spcont;
 	    uint offp;
 	    sp_instr_cpush *i;
 
-	    if (spc->find_cursor(&$2, &offp, TRUE))
+	    if (ctx->find_cursor(&$2, &offp, TRUE))
 	    {
 	      net_printf(YYTHD, ER_SP_DUP_CURS, $2.str);
 	      delete $5;
 	      YYABORT;
 	    }
-            i= new sp_instr_cpush(sp->instructions(), $5);
+            i= new sp_instr_cpush(sp->instructions(), ctx, $5);
 	    sp->add_instr(i);
-	    lex->spcont->push_cursor(&$2);
+	    ctx->push_cursor(&$2);
 	    $$.vars= $$.conds= $$.hndlrs= 0;
 	    $$.curs= 1;
 	  }
@@ -1748,7 +1752,8 @@ sp_proc_stmt:
 	      }
 	      else
 	      {
-		sp_instr_stmt *i=new sp_instr_stmt(lex->sphead->instructions());
+		sp_instr_stmt *i=new sp_instr_stmt(lex->sphead->instructions(),
+						   lex->spcont);
 
 		i->set_lex(lex);
 		lex->sphead->add_instr(i);
@@ -1776,6 +1781,7 @@ sp_proc_stmt:
 	        YYABORT;
 	      }
 	      i= new sp_instr_freturn(lex->sphead->instructions(),
+				      lex->spcont,
 		                      $2, lex->sphead->m_returns);
 	      lex->sphead->add_instr(i);
 	      lex->sphead->m_has_return= TRUE;
@@ -1794,8 +1800,9 @@ sp_proc_stmt:
 	       at the same frame level, so we then know that it's the
 	       top-most variable in the frame. */
 	    LEX *lex= Lex;
-	    uint offset= lex->spcont->current_framesize();
+	    uint offset= lex->spcont->current_pvars();
 	    sp_instr_set *i = new sp_instr_set(lex->sphead->instructions(),
+					       lex->spcont,
 	                                       offset, $2, MYSQL_TYPE_STRING);
 	    LEX_STRING dummy;
 
@@ -1839,19 +1846,17 @@ sp_proc_stmt:
 	    else
 	    {
 	      uint ip= sp->instructions();
-	      sp_scope_t sdiff;
 	      sp_instr_jump *i;
 	      sp_instr_hpop *ih;
 	      sp_instr_cpop *ic;
 
-	      ctx->diff_scopes(0, &sdiff);
-	      ih= new sp_instr_hpop(ip++, sdiff.hndlrs);
+	      ih= new sp_instr_hpop(ip++, ctx, 0);
 	      sp->push_backpatch(ih, lab);
 	      sp->add_instr(ih);
-	      ic= new sp_instr_cpop(ip++, sdiff.curs);
+	      ic= new sp_instr_cpop(ip++, ctx, 0);
 	      sp->push_backpatch(ic, lab);
 	      sp->add_instr(ic);
-	      i= new sp_instr_jump(ip);
+	      i= new sp_instr_jump(ip, ctx);
 	      sp->push_backpatch(i, lab);  /* Jumping forward */
               sp->add_instr(i);
 	    }
@@ -1872,14 +1877,15 @@ sp_proc_stmt:
 	    {
 	      sp_instr_jump *i;
 	      uint ip= sp->instructions();
-	      sp_scope_t sdiff;
-
-	      ctx->diff_scopes(lab->scopes, &sdiff);
-	      if (sdiff.hndlrs)
-	        sp->add_instr(new sp_instr_hpop(ip++, sdiff.hndlrs));
-	      if (sdiff.curs)
-	        sp->add_instr(new sp_instr_cpop(ip++, sdiff.curs));
-	      i= new sp_instr_jump(ip, lab->ip); /* Jump back */
+	      uint n;
+
+	      n= ctx->diff_handlers(lab->ctx);
+	      if (n)
+	        sp->add_instr(new sp_instr_hpop(ip++, ctx, n));
+	      n= ctx->diff_cursors(lab->ctx);
+	      if (n)
+	        sp->add_instr(new sp_instr_cpop(ip++, ctx, n));
+	      i= new sp_instr_jump(ip, ctx, lab->ip); /* Jump back */
               sp->add_instr(i);
 	    }
 	  }
@@ -1890,8 +1896,6 @@ sp_proc_stmt:
 	    sp_pcontext *ctx= lex->spcont;
 	    sp_label_t *lab= ctx->find_label($2.str);
 
-	    if (! lab)
-	      lab= ctx->find_glabel($2.str);
 	    if (lab)
 	    {
 	      net_printf(YYTHD, ER_SP_LABEL_REDEFINE, $2.str);
@@ -1899,9 +1903,9 @@ sp_proc_stmt:
 	    }
 	    else
 	    {
-	      lab= ctx->push_glabel($2.str, sp->instructions());
+	      lab= ctx->push_label($2.str, sp->instructions());
 	      lab->type= SP_LAB_GOTO;
-	      lab->scopes= ctx->scopes();
+	      lab->ctx= ctx;
               sp->backpatch(lab);
 	    }
 	  }
@@ -1911,48 +1915,52 @@ sp_proc_stmt:
 	    sp_head *sp= lex->sphead;
 	    sp_pcontext *ctx= lex->spcont;
 	    uint ip= lex->sphead->instructions();
-	    sp_label_t *lab= ctx->find_label($2.str);
-	    sp_scope_t sdiff;
+	    sp_label_t *lab;
 	    sp_instr_jump *i;
 	    sp_instr_hpop *ih;
 	    sp_instr_cpop *ic;
 
-	    if (! lab)
-	      lab= ctx->find_glabel($2.str);
-
+	    if (sp->m_in_handler)
+	    {
+	      send_error(lex->thd, ER_SP_GOTO_IN_HNDLR);
+	      YYABORT;
+	    }
+	    lab= ctx->find_label($2.str);
 	    if (! lab)
 	    {
 	      lab= (sp_label_t *)YYTHD->alloc(sizeof(sp_label_t));
 	      lab->name= $2.str;
 	      lab->ip= 0;
 	      lab->type= SP_LAB_REF;
-	      lab->scopes= 0;
+	      lab->ctx= ctx;
 
-	      ctx->diff_scopes(0, &sdiff);
-	      ih= new sp_instr_hpop(ip++, sdiff.hndlrs);
+	      ih= new sp_instr_hpop(ip++, ctx, 0);
 	      sp->push_backpatch(ih, lab);
 	      sp->add_instr(ih);
-	      ic= new sp_instr_cpop(ip++, sdiff.curs);
+	      ic= new sp_instr_cpop(ip++, ctx, 0);
 	      sp->add_instr(ic);
 	      sp->push_backpatch(ic, lab);
-	      i= new sp_instr_jump(ip);
+	      i= new sp_instr_jump(ip, ctx);
 	      sp->push_backpatch(i, lab);  /* Jumping forward */
 	      sp->add_instr(i);
 	    }
 	    else
 	    {
-	      ctx->diff_scopes(lab->scopes, &sdiff);
-	      if (sdiff.hndlrs)
+	      uint n;
+
+	      n= ctx->diff_handlers(lab->ctx);
+	      if (n)
 	      {
-	        ih= new sp_instr_hpop(ip++, sdiff.hndlrs);
+	        ih= new sp_instr_hpop(ip++, ctx, n);
 	        sp->add_instr(ih);
 	      }
-	      if (sdiff.curs)
+	      n= ctx->diff_cursors(lab->ctx);
+	      if (n)
 	      {
-	        ic= new sp_instr_cpop(ip++, sdiff.curs);
+	        ic= new sp_instr_cpop(ip++, ctx, n);
 	        sp->add_instr(ic);
 	      }
-	      i= new sp_instr_jump(ip, lab->ip); /* Jump back */
+	      i= new sp_instr_jump(ip, ctx, lab->ip); /* Jump back */
 	      sp->add_instr(i);
 	    }
 	  }
@@ -1968,7 +1976,7 @@ sp_proc_stmt:
 	      net_printf(YYTHD, ER_SP_CURSOR_MISMATCH, $2.str);
 	      YYABORT;
 	    }
-	    i= new sp_instr_copen(sp->instructions(), offset);
+	    i= new sp_instr_copen(sp->instructions(), lex->spcont, offset);
 	    sp->add_instr(i);
 	  }
 	| FETCH_SYM ident INTO
@@ -1983,7 +1991,7 @@ sp_proc_stmt:
 	      net_printf(YYTHD, ER_SP_CURSOR_MISMATCH, $2.str);
 	      YYABORT;
 	    }
-	    i= new sp_instr_cfetch(sp->instructions(), offset);
+	    i= new sp_instr_cfetch(sp->instructions(), lex->spcont, offset);
 	    sp->add_instr(i);
 	  }
 	  sp_fetch_list
@@ -2000,7 +2008,7 @@ sp_proc_stmt:
 	      net_printf(YYTHD, ER_SP_CURSOR_MISMATCH, $2.str);
 	      YYABORT;
 	    }
-	    i= new sp_instr_cclose(sp->instructions(), offset);
+	    i= new sp_instr_cclose(sp->instructions(), lex->spcont,  offset);
 	    sp->add_instr(i);
 	  }
 	;
@@ -2056,7 +2064,7 @@ sp_if:
 	    sp_head *sp= lex->sphead;
 	    sp_pcontext *ctx= lex->spcont;
 	    uint ip= sp->instructions();
-	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, $1);
+	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, ctx, $1);
 
 	    i->tables= lex->query_tables;
 	    lex->query_tables= 0;
@@ -2068,7 +2076,7 @@ sp_if:
 	    sp_head *sp= Lex->sphead;
 	    sp_pcontext *ctx= Lex->spcont;
 	    uint ip= sp->instructions();
-	    sp_instr_jump *i = new sp_instr_jump(ip);
+	    sp_instr_jump *i = new sp_instr_jump(ip, ctx);
 
 	    sp->add_instr(i);
 	    sp->backpatch(ctx->pop_label());
@@ -2098,7 +2106,7 @@ sp_case:
 	    sp_instr_jump_if_not *i;
 
 	    if (! sp->m_simple_case)
-	      i= new sp_instr_jump_if_not(ip, $1);
+	      i= new sp_instr_jump_if_not(ip, ctx, $1);
 	    else
 	    { /* Simple case: <caseval> = <whenval> */
 	      LEX_STRING ivar;
@@ -2106,10 +2114,10 @@ sp_case:
 	      ivar.str= (char *)"_tmp_";
 	      ivar.length= 5;
 	      Item *var= (Item*) new Item_splocal(ivar, 
-						  ctx->current_framesize()-1);
+						  ctx->current_pvars()-1);
 	      Item *expr= new Item_func_eq(var, $1);
 
-	      i= new sp_instr_jump_if_not(ip, expr);
+	      i= new sp_instr_jump_if_not(ip, ctx, expr);
               lex->variables_used= 1;
 	    }
 	    sp->push_backpatch(i, ctx->push_label((char *)"", 0));
@@ -2122,7 +2130,7 @@ sp_case:
 	    sp_head *sp= Lex->sphead;
 	    sp_pcontext *ctx= Lex->spcont;
 	    uint ip= sp->instructions();
-	    sp_instr_jump *i = new sp_instr_jump(ip);
+	    sp_instr_jump *i = new sp_instr_jump(ip, ctx);
 
 	    sp->add_instr(i);
 	    sp->backpatch(ctx->pop_label());
@@ -2141,7 +2149,8 @@ sp_whens:
 	  {
 	    sp_head *sp= Lex->sphead;
 	    uint ip= sp->instructions();
-	    sp_instr_error *i= new sp_instr_error(ip, ER_SP_CASE_NOT_FOUND);
+	    sp_instr_error *i= new sp_instr_error(ip, Lex->spcont,
+						  ER_SP_CASE_NOT_FOUND);
 
 	    sp->add_instr(i);
 	  }
@@ -2166,7 +2175,6 @@ sp_labeled_control:
 	      lab= lex->spcont->push_label($1.str,
 	                                   lex->sphead->instructions());
 	      lab->type= SP_LAB_ITER;
-	      lab->scopes= ctx->scopes();
 	    }
 	  }
 	  sp_unlabeled_control sp_opt_label
@@ -2204,32 +2212,24 @@ sp_unlabeled_control:
 	    sp_label_t *lab= lex->spcont->last_label();
 
 	    lab->type= SP_LAB_BEGIN;
-	    /* Scope duplicate checking */
-	    lex->spcont->push_scope();
+	    lex->spcont= lex->spcont->push_context();
 	  }
 	  sp_decls
-	  {
-	    Lex->spcont->push_handlers($3.hndlrs);
-	  }
 	  sp_proc_stmts
 	  END
 	  {
 	    LEX *lex= Lex;
 	    sp_head *sp= lex->sphead;
 	    sp_pcontext *ctx= lex->spcont;
-	    sp_scope_t scope;
 
   	    sp->backpatch(ctx->last_label());	/* We always have a label */
-	    ctx->pop_pvar($3.vars);
-	    ctx->pop_cond($3.conds);
-	    ctx->pop_handlers($3.hndlrs);
-	    ctx->pop_cursor($3.curs);
 	    if ($3.hndlrs)
-	      sp->add_instr(new sp_instr_hpop(sp->instructions(), $3.hndlrs));
+	      sp->add_instr(new sp_instr_hpop(sp->instructions(), ctx,
+					      $3.hndlrs));
 	    if ($3.curs)
-	      sp->add_instr(new sp_instr_cpop(sp->instructions(), $3.curs));
-	    ctx->pop_scope(&scope);
-	    ctx->pop_glabel(scope.glab);
+	      sp->add_instr(new sp_instr_cpop(sp->instructions(), ctx,
+					      $3.curs));
+	    lex->spcont= ctx->pop_context();
 	  }
 	| LOOP_SYM
 	  sp_proc_stmts END LOOP_SYM
@@ -2237,7 +2237,7 @@ sp_unlabeled_control:
 	    LEX *lex= Lex;
 	    uint ip= lex->sphead->instructions();
 	    sp_label_t *lab= lex->spcont->last_label();  /* Jumping back */
-	    sp_instr_jump *i = new sp_instr_jump(ip, lab->ip);
+	    sp_instr_jump *i = new sp_instr_jump(ip, lex->spcont, lab->ip);
 
 	    lex->sphead->add_instr(i);
 	  }
@@ -2246,7 +2246,8 @@ sp_unlabeled_control:
 	    LEX *lex= Lex;
 	    sp_head *sp= lex->sphead;
 	    uint ip= sp->instructions();
-	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, $2);
+	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, lex->spcont,
+							       $2);
 
 	    /* Jumping forward */
 	    sp->push_backpatch(i, lex->spcont->last_label());
@@ -2259,7 +2260,7 @@ sp_unlabeled_control:
 	    LEX *lex= Lex;
 	    uint ip= lex->sphead->instructions();
 	    sp_label_t *lab= lex->spcont->last_label();  /* Jumping back */
-	    sp_instr_jump *i = new sp_instr_jump(ip, lab->ip);
+	    sp_instr_jump *i = new sp_instr_jump(ip, lex->spcont, lab->ip);
 
 	    lex->sphead->add_instr(i);
 	  }
@@ -2268,7 +2269,8 @@ sp_unlabeled_control:
 	    LEX *lex= Lex;
 	    uint ip= lex->sphead->instructions();
 	    sp_label_t *lab= lex->spcont->last_label();  /* Jumping back */
-	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, $4, lab->ip);
+	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, lex->spcont,
+							       $4, lab->ip);
 
 	    i->tables= lex->query_tables;
 	    lex->query_tables= 0;
@@ -6786,11 +6788,12 @@ option_value:
 	    }
             else
 	    { /* An SP local variable */
+	      sp_pcontext *ctx= lex->spcont;
 	      sp_pvar_t *spv;
               sp_instr_set *i;
 	      Item *it;
 
-	      spv= lex->spcont->find_pvar(&$1.base_name);
+	      spv= ctx->find_pvar(&$1.base_name);
 
 	      if ($3)
 	        it= $3;
@@ -6798,7 +6801,7 @@ option_value:
 	        it= spv->dflt;
 	      else
 	        it= new Item_null();
-              i= new sp_instr_set(lex->sphead->instructions(),
+              i= new sp_instr_set(lex->sphead->instructions(), ctx,
 	                          spv->offset, it, spv->type);
 	      i->tables= lex->query_tables;
 	      lex->query_tables= 0;