Line data    Source code

       1             : /*
       2             :  * SPDX-License-Identifier: MPL-2.0
       3             :  *
       4             :  * This Source Code Form is subject to the terms of the Mozilla Public
       5             :  * License, v. 2.0.  If a copy of the MPL was not distributed with this
       6             :  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
       7             :  *
       8             :  * Copyright 2024 MonetDB Foundation;
       9             :  * Copyright August 2008 - 2023 MonetDB B.V.;
      10             :  * Copyright 1997 - July 2008 CWI.
      11             :  */
      12             : 
      13             : #include "monetdb_config.h"
      14             : #include "opt_garbageCollector.h"
      15             : #include "mal_interpreter.h"
      16             : #include "mal_builder.h"
      17             : #include "mal_function.h"
      18             : #include "opt_prelude.h"
      19             : 
      20             : /* The garbage collector is focused on removing temporary BATs only.
      21             :  * Leaving some garbage on the stack is an issue.
      22             :  *
      23             :  * The end-of-life of a BAT may lay within block bracket. This calls
      24             :  * for care, as the block may trigger a loop and then the BATs should
      25             :  * still be there.
      26             :  *
      27             :  * The life time of such BATs is forcefully terminated after the block exit.
      28             :  */
      29             : 
      30             : str
      31      554925 : OPTgarbageCollectorImplementation(Client cntxt, MalBlkPtr mb, MalStkPtr stk,
      32             :                                                                   InstrPtr pci)
      33             : {
      34      554925 :         int i, limit;
      35      554925 :         InstrPtr p;
      36      554925 :         int actions = 0;
      37      554925 :         str msg = MAL_SUCCEED;
      38             : 
      39      554925 :         (void) stk;
      40      554925 :         if (mb->inlineProp)
      41           0 :                 goto wrapup;
      42             : 
      43      554925 :         limit = mb->stop;
      44             : 
      45             : 
      46             :         // move SQL query definition to the front for event profiling tools
      47      554925 :         p = NULL;
      48    11672102 :         for (i = 0; i < limit; i++)
      49    11366950 :                 if (mb->stmt[i] && getModuleId(mb->stmt[i]) == querylogRef
      50      249760 :                         && getFunctionId(mb->stmt[i]) == defineRef) {
      51             :                         p = getInstrPtr(mb, i);
      52             :                         break;
      53             :                 }
      54             : 
      55      554925 :         if (p != NULL) {
      56      249808 :                 for (; i > 1; i--)
      57          35 :                         mb->stmt[i] = mb->stmt[i - 1];
      58      249773 :                 mb->stmt[1] = p;
      59      249773 :                 actions = 1;
      60             :         }
      61             :         // Actual garbage collection stuff, just mark them for re-assessment
      62      554925 :         p = NULL;
      63    12223966 :         for (i = 0; i < limit; i++) {
      64    12223966 :                 p = getInstrPtr(mb, i);
      65    12223966 :                 p->gc = false;
      66    12223966 :                 p->typeresolved = false;
      67             :                 /* Set the program counter to ease profiling */
      68    12223966 :                 p->pc = i;
      69    12223966 :                 if (p->token == ENDsymbol)
      70             :                         break;
      71             :         }
      72             : 
      73             :         //mnstr_printf(cntxt->fdout,"garbacollector limit %d ssize %d vtop %d vsize %d\n", limit, (int)(mb->ssize), mb->vtop, (int)(mb->vsize));
      74             :         /* A good MAL plan should end with an END instruction */
      75      554925 :         if (p && p->token != ENDsymbol) {
      76           0 :                 throw(MAL, "optimizer.garbagecollector",
      77             :                           SQLSTATE(42000) "Incorrect MAL plan encountered");
      78             :         }
      79             :         /* move sanity check to other optimizer */
      80      554925 :         getInstrPtr(mb, 0)->gc = true;
      81             : 
      82             :         /* leave a consistent scope admin behind */
      83      554925 :         setVariableScope(mb);
      84             :         /* Defense line against incorrect plans */
      85      554922 :         if (actions > 0) {
      86      249770 :                 if (!msg)
      87      249770 :                         msg = chkTypes(cntxt->usermodule, mb, FALSE);
      88      249757 :                 if (!msg)
      89      249757 :                         msg = chkFlow(mb);
      90      249768 :                 if (!msg)
      91      249768 :                         msg = chkDeclarations(mb);
      92             :         }
      93             :         /* keep all actions taken as a post block comment */
      94      305152 :   wrapup:
      95             :         /* keep actions taken as a fake argument */
      96      554923 :         (void) pushInt(mb, pci, actions);
      97      554923 :         return msg;
      98             : }