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             : 
      19             : /* The garbage collector is focused on removing temporary BATs only.
      20             :  * Leaving some garbage on the stack is an issue.
      21             :  *
      22             :  * The end-of-life of a BAT may lay within block bracket. This calls
      23             :  * for care, as the block may trigger a loop and then the BATs should
      24             :  * still be there.
      25             :  *
      26             :  * The life time of such BATs is forcefully terminated after the block exit.
      27             :  */
      28             : 
      29             : str
      30      569406 : OPTgarbageCollectorImplementation(Client cntxt, MalBlkPtr mb, MalStkPtr stk,
      31             :                                                                   InstrPtr pci)
      32             : {
      33      569406 :         int i, limit;
      34      569406 :         InstrPtr p;
      35      569406 :         int actions = 0;
      36      569406 :         str msg = MAL_SUCCEED;
      37             : 
      38      569406 :         (void) stk;
      39      569406 :         if (mb->inlineProp)
      40           0 :                 goto wrapup;
      41             : 
      42      569406 :         limit = mb->stop;
      43             : 
      44             : 
      45             :         // move SQL query definition to the front for event profiling tools
      46      569406 :         p = NULL;
      47    12538004 :         for (i = 0; i < limit; i++)
      48    12217978 :                 if (mb->stmt[i] && getModuleId(mb->stmt[i]) == querylogRef
      49      248926 :                         && getFunctionId(mb->stmt[i]) == defineRef) {
      50             :                         p = getInstrPtr(mb, i);
      51             :                         break;
      52             :                 }
      53             : 
      54      569406 :         if (p != NULL) {
      55      249510 :                 for (; i > 1; i--)
      56          35 :                         mb->stmt[i] = mb->stmt[i - 1];
      57      249475 :                 mb->stmt[1] = p;
      58      249475 :                 actions = 1;
      59             :         }
      60             :         // Actual garbage collection stuff, just mark them for re-assessment
      61      569406 :         p = NULL;
      62    17656146 :         for (i = 0; i < limit; i++) {
      63    17656681 :                 p = getInstrPtr(mb, i);
      64    17656681 :                 p->gc = false;
      65    17656681 :                 p->typeresolved = false;
      66             :                 /* Set the program counter to ease profiling */
      67    17656681 :                 p->pc = i;
      68    17656681 :                 if (p->token == ENDsymbol)
      69             :                         break;
      70             :         }
      71             : 
      72             :         //mnstr_printf(cntxt->fdout,"garbacollector limit %d ssize %d vtop %d vsize %d\n", limit, (int)(mb->ssize), mb->vtop, (int)(mb->vsize));
      73             :         /* A good MAL plan should end with an END instruction */
      74      569406 :         if (p && p->token != ENDsymbol) {
      75           0 :                 throw(MAL, "optimizer.garbagecollector",
      76             :                           SQLSTATE(42000) "Incorrect MAL plan encountered");
      77             :         }
      78             :         /* move sanity check to other optimizer */
      79      569406 :         getInstrPtr(mb, 0)->gc = true;
      80             : 
      81             :         /* leave a consistent scope admin behind */
      82      569406 :         setVariableScope(mb);
      83             :         /* Defense line against incorrect plans */
      84      569869 :         if (actions > 0) {
      85      249938 :                 if (!msg)
      86      249938 :                         msg = chkTypes(cntxt->usermodule, mb, FALSE);
      87      249966 :                 if (!msg)
      88      249720 :                         msg = chkFlow(mb);
      89      250005 :                 if (!msg)
      90      250005 :                         msg = chkDeclarations(mb);
      91             :         }
      92             :         /* keep all actions taken as a post block comment */
      93      319931 :   wrapup:
      94             :         /* keep actions taken as a fake argument */
      95      570332 :         (void) pushInt(mb, pci, actions);
      96      570332 :         return msg;
      97             : }