gen.c

本工具提供一个词法分析器和语法分析器的集成开发环境

	if ( !GenCC ) gen1("zzEXIT(zztasp%d);\n", BlkLevel);
	if ( !GenCC ) gen("}\n");
	tabs--;
	gen("}\n");
}

static void
#ifdef __USE_PROTOS
BLOCK_Preamble( Junction *q )
#else
BLOCK_Preamble( q )
Junction *q;
#endif
{
	ActionNode *a;
	Junction *begin;

	BLOCK_Head();
	if ( GenCC ) genTokenPointers(q);
	if ( GenCC&&GenAST ) genASTPointers(q);
	if ( q->jtype == aPlusBlk ) gen("int zzcnt=1;\n");
	if ( q->parm != NULL && !q->predparm ) gen1("zzaPush(%s);\n", q->parm)
	else if ( !GenCC ) gen("zzMake0;\n");
	if ( !GenCC ) gen("{\n");
	if ( q->jtype == aLoopBegin ) begin = (Junction *) ((Junction *)q->p1);
	else begin = q;
	if ( has_guess_block_as_first_item(begin) )
	{
		gen("zzGUESS_BLOCK\n");
	}
	if ( q->jtype == aLoopBegin )
		a = findImmedAction( ((Junction *)q->p1)->p1 );	/* look at aLoopBlk */
	else
		a = findImmedAction( q->p1 );
	if ( a!=NULL && !a->is_predicate) {
		if (!a->noHoist) dumpAction(a->action, output, tabs, a->file, a->line, 1);
		a->done = 1;	/* remove action. We have already handled it */
	}
}

void
#ifdef __USE_PROTOS
genCombinedPredTreeContextOrig( Predicate *p )
#else
genCombinedPredTreeContextOrig( p )
Predicate *p;
#endif
{
	static set *ctx=NULL;		/* genExprSets() is destructive, make copy*/
	require(p!=NULL, "can't make context tree for NULL pred tree");

#ifdef DBG_PRED
	fprintf(stderr, "enter genCombinedPredTreeContextOrig(%s,0x%x) with sets:\n", p->expr, p);
	s_fprT(stderr, p->scontext[1]);
	fprintf(stderr, "\n");
#endif
	if ( p->down == NULL )
	{
/***	if ( p->k>1 && p->tcontext!=NULL ) ***/
		if ( p->tcontext!=NULL )
		{
			_gen("(");
			genExprTree(p->tcontext, 1);
			_gen(")");
		}
/***	else if ( p->k==1 && set_deg(p->scontext[1])>0 ) ***/
		else if ( set_deg(p->scontext[1])>0 )
		{
			if ( ctx==NULL ) ctx = (set *)calloc(CLL_k+1, sizeof(set));
			require(ctx!=NULL, "ctx cannot allocate");
			ctx[0]=empty;
			ctx[1]=set_dup(p->scontext[1]);
			_gen("(");
			genExprSets(&(ctx[0]), p->k);
			_gen(")");
			set_free(ctx[1]);
		}
		else if ( p->expr==PRED_AND_LIST || p->expr==PRED_OR_LIST ) {
			fatal_internal("pred tree is orphan OR or AND list");
		}
		else {
            if (! HoistPredicateContext) {
              _gen(" 1 /* no context: prc is off */ ");
            } else {
              fatal_internal("pred tree context is empty");
            };
		}
		return;
	}

/* MR10 - make AND just like OR */

	if ( p->expr == PRED_AND_LIST )
	{
        Predicate *list = p->down;
        for (; list!=NULL; list=list->right)
        {
     	     genCombinedPredTreeContextOrig(list);
       		 if ( list->right!=NULL ) _gen("|| /* MR10 was wrong */ ");
        };
		return;
	}

	if ( p->expr == PRED_OR_LIST )
	{
        Predicate *list = p->down;
        for (; list!=NULL; list=list->right)
        {
           genCombinedPredTreeContextOrig(list);
           if ( list->right!=NULL ) _gen("||");
        };
        return;
     };

	fatal("pred tree is really wacked");
}

/* [genCombinedPredTreeContext] */

void
#ifdef __USE_PROTOS
genCombinedPredTreeContext( Predicate *p )
#else
genCombinedPredTreeContext( p )
Predicate *p;
#endif
{
  Tree  *t;
  int   predDepth=0;

  if (0 && ! MR_usingPredNames && ! MRhoisting) {
    genCombinedPredTreeContextOrig(p);
  } else {
/* MR13 */    MR_pred_depth(p,&predDepth);
/* MR13 */    if (predDepth == 1) {
/* MR13 */
/* MR13 */      set   scontext[2];
/* MR13 */      scontext[0]=empty;
/* MR13 */      scontext[1]=MR_compute_pred_set(p);
/* MR13 */      if (set_nil(scontext[1])) {
/* MR13 */        _gen(" 1 /* MR12 no context (-prc off) */ ");
/* MR13 */      } else {
/* MR13 */        _gen("(");
/* MR13 */        genExprSets(&scontext[0], 1);
/* MR13 */        set_free(scontext[1]);
/* MR13 */        _gen(")");
/* MR13 */      };

    } else {
      t=MR_compute_pred_tree_context(p);
      if (t == NULL) {
        _gen(" 1 /* MR12 no context (-prc off) */ ");
      } else {
        _gen("(");
        genExprTree(t, 1);
        Tfree(t);   /* MR10 */
        _gen(")");
      };
    };
  };
}

/* [genPredTreeGate] */

void
#ifdef __USE_PROTOS
genPredTreeGate( Predicate *p, int in_and_expr )
#else
genPredTreeGate( p, in_and_expr )
Predicate *p;
int in_and_expr;
#endif
{
	if ( in_and_expr )
	{
		_gen("!(");
		genCombinedPredTreeContext(p);
		_gen(")||");
		if ( p->down!=NULL ) _gen("\n");
	}
	else
	{
		_gen("(");
		genCombinedPredTreeContext(p);
		_gen(")&&");
		if ( p->down!=NULL ) _gen("\n");
	}
}

#ifdef __USE_PROTOS
void genPredEntry(Predicate *p,int outer)
#else
void genPredEntry(p,outer)
  Predicate     *p;
  int           outer;
#endif
{
    int         inverted=0;
    Predicate   *q;
    int         localOuter=outer;
    int         needRP=0;

    if (p == NULL) return;

    if (p->predEntry != NULL && p->predEntry->predLiteral != NULL) {
      if (p->inverted != p->predEntry->pred->inverted) {
        _gen("! /* inverted pred */ (");
        needRP=1;
      } else {
        if (!localOuter) _gen("(");
        needRP=1;
      };
      dumpAction(p->predEntry->predLiteral,output,0,p->source->file,p->source->line,0);
      if (needRP) _gen(")");
      return;
    };

    inverted=p->inverted;

    if (inverted) {
      _gen(" ! /* inverted pred */ (");
      localOuter=1;
    };

    if (p->expr == PRED_OR_LIST) {
      if (!localOuter) _gen("(");
      for (q=p->down; q != NULL ; q=q->right) {
        genPredEntry(q,0);
        if (q->right != NULL) _gen(" || ");
      };
      if (!localOuter) _gen(")");
    } else if (p->expr == PRED_AND_LIST) {
      if (!localOuter) _gen("(");
      for (q=p->down; q != NULL ; q=q->right) {
        genPredEntry(q,0);
        if (q->right != NULL) _gen(" && ");
      };
      if (!localOuter) _gen(")");
    } else {
      if (!localOuter) _gen("(");
      require (p->source != NULL,"predEntry->source == NULL");
      require (p->source->inverted == 0,"dumpPredEntry p->source->inverted != 0");
      dumpAction(p->source->action,output,0,p->source->file,p->source->line,0);
      if (!localOuter) _gen(")");
    };

    if (inverted) {
        _gen(")");
    }
}

void
#ifdef __USE_PROTOS
dumpPredAction(ActionNode *anode,
                    char *s,FILE *output,int tabs,int file,int line,int final_newline)
#else
dumpPredAction(anode,
                    s,output,tabs,file,line,final_newline)

    ActionNode  *anode;
    char        *s;
    FILE        *output;
    int         tabs;
    int         file;
    int         line;
    int         final_newline;
#endif
{
    PredEntry   *predEntry=anode->predEntry;
    int         inverted=anode->inverted;
    Predicate   *workPred;

    if (predEntry == NULL) {

      /* inline predicate literal */

      require(inverted == 0,"dumpPredAction action->inverted");
  	  dumpAction(s,output,tabs,file,line,final_newline);

    } else {

      /* a reference to a predicate - possibly with an inverted source */

      if (predEntry->predLiteral != NULL) {
        if (inverted) _gen("! /* inverted pred */ (");
        dumpAction(predEntry->predLiteral,output,0,anode->file,anode->line,0);
        if (inverted) _gen(")");
      } else {
        workPred=predicate_dup(predEntry->pred);
        if (inverted) workPred->inverted=!workPred->inverted;
        genPredEntry(workPred,1);
        predicate_free(workPred);
      };
    };
}

/* [genPred] */

void
#ifdef __USE_PROTOS
genPred(Predicate *p, Node *j,int suppress_sva)
#else
genPred(p,j,suppress_sva)
    Predicate   *p;
    Node        *j;
    int         suppress_sva;
#endif
{
	if ( FoundException && !suppress_sva) {_gen("(_sva=(");}    /* MR11 suppress_sva */
	else {_gen("(");}
	if ( GenLineInfo && j->file != -1 ) _gen("\n");
    if (p->source != NULL && p->source->ampersandPred != NULL) {
      if (p->source->ampersandPred->k == 1) {

            set     ctx[2];

			ctx[0]=empty;
			ctx[1]=set_dup(p->source->ampersandPred->scontext[1]);

			_gen("(");
			genExprSets(&(ctx[0]), p->k);
			_gen(") && ");
			set_free(ctx[1]);
      } else {
        _gen("( ");
        genExprTree(p->source->ampersandPred->tcontext,1);
		_gen(" ) && ");
      };
    };

    dumpPredAction((ActionNode *)p->source,
                p->expr, output, 0, -1 /*indicates no line info*/, j->line, 0);

	if ( FoundException && !suppress_sva)   /* MR11 suppress_sva */
         {_gen("),_sva)");}    /* MR10 - get red of "meant ==" messages */
	else {_gen(")");}
}

void
#ifdef __USE_PROTOS
MR_distinctORcontextOpt(Predicate *p,Node *j,int in_and_expr)
#else
MR_distinctORcontextOpt(p,j,in_and_expr)
    Predicate   *p;
    Node        *j;
    int         in_and_expr;
#endif
{
    Predicate   *q;

    _gen(" /* MR10 Distinct OR context optimization */ \n");

    if (in_and_expr) {
      gen("zzpf=0,\n");
      for (q=p->down; q != NULL; q=q->right) {
        gen("(  ");
        genCombinedPredTreeContext(q);
        _gen(" && (zzpf=1, ");
        genPred(q,j,0);
        _gen("  )) ||\n");
      };
      gen("!zzpf)");
    } else {
      require (0,
            "MR_distinctORcontextOpt: can't get here when using MR_predSimplify");
#if 0
**      for (q=p->down; q != NULL; q=q->right) {
**        gen("(  ");
**        genCombinedPredTreeContext(q);
**        _gen(" && ");
**        genPred(q,j);
**        if (q->right != NULL) {
**          _gen("  ) ||\n");
**        };
**      };
**      gen(")");
#endif
   };
}

void
#ifdef __USE_PROTOS
genPredTreeOrig( Predicate *p, Node *j, int in_and_expr )
#else
genPredTreeOrig( p, j, in_and_expr )
Predicate *p;
Node *j;
int in_and_expr;
#endif
{

/* MR10 */  int     allHaveContext=1;
/* MR10 */  int     noneHaveContext=1;

/* MR10 */  MR_predContextPresent(p,&allHaveContext,&noneHaveContext);

	if ( ! noneHaveContext )                  /* MR10 context guards ignored when -prc off */
	{
		_gen("(");
		genPredTreeGate(p, in_and_expr);
	}

	/* if leaf node, just gen predicate */

	if ( p->down==NULL )
	{
		genPred(p,j,0);
		if ( ! noneHaveContext ) _gen(")");   /* MR10 context guards ignored when -prc off */
		return;
	}

	/* if AND list, do both preds (only two possible) */
	if ( p->expr == PRED_AND_LIST )
	{
#if 0
**		_gen("(");
**		genPredTreeOrig(p->down, j, 1);
**		_gen("&&");
**		genPredTreeOrig(p->down->right, j, 1);
**		_gen(")");
**		if ( ! noneHaveContext ) _gen(")");    /* MR10 context guards ignored when -prc off */
**		return;
#endif
        /* MR11 - make it work with AND with more than two children - like OR */

		Predicate *list;
		_gen("(");
		list = p->down;
		for (; list!=NULL; list=list->right)
		{
			genPredTreeOrig(list, j, 1);
			if ( list->right!=NULL ) _gen("&&");
		}
		_gen(")");
		if ( ! noneHaveContext ) _gen(")");    /* MR10 context guards ignored when -prc off */
		return;
    };

	if ( p->expr == PRED_OR_LIST )
	{
		Predicate *list;
		_gen("(");
		list = p->down;
		for (; list!=NULL; list=list->right)
		{
			genPredTreeOrig(list, j, 0);
			if ( list->right!=NULL ) _gen("||");
		}
		_gen(")");
		if ( ! noneHaveContext ) _gen(")");    /* MR10 context guards ignored when -prc off */
		return;
	}

	fatal_internal("genPredTreeOrig: predicate tree is wacked");
}

#if 0
**   Predicate member dummyPredDepth is no longer used in MR10
**     but we might need it again in the future
**
**   if (MRhoisting) {
**     if ( !noneHaveContext &&
**          ! in_and_expr &&
**          p->source != NULL &&
**          p->source->dummyPredicateDepth > 0 &&
**          p->down == NULL) {
** 		_gen("(");
** 		genCombinedPredTreeContext(p);
** 		_gen("  )\n");
** 		return;
**     };
**   };
#endif

/* [genPredTree] */

/* in_and_expr

   what to do if the context is wrong
   what to do if the context is correct but the predicate is false

   remember: if the context is wrong it's the same as if the
             predicate is true as far as enabling an alternative

        Consider (AND p q r)

        if in an ... && ... expression then you don't want
        the entire predicate chain to fail just because the
        context for one component is wrong: so return true

        Consider (OR p q r)

        if in an ... || ... expression then you don't want
        the entire predicate chain to succeed just because
        the context for one component is correct when the
        corresponding test is false: so return false when
        the context is correct but the test is false.
*/

void
#ifdef __USE_PROTOS