init.c

花了很长时间找了这么多c语言的编译器

	sp->extflag = TRUE;
	q->val.sp = sp;
	q->offset = val;
	sptr = &(*sptr)->link;
	q->mode = ispc ? dd_pcname : dd_dataname;
}
int makestorage(long val)
{
	struct decldata *q = *sptr = xalloc(sizeof(struct decldata));
	q->val.i = val;
	sptr = &(*sptr)->link;
	q->mode = dd_storage;
}
int agflush(int size, long val)
/*
 * flush a bit field when it is full
 */
{
	struct decldata *q = *sptr = xalloc(sizeof(struct decldata));
	q->val.i = val;
	sptr = &(*sptr)->link;
	switch (size) {
		case 1:
			q->mode = dd_byte;
			return 1;
		case 2:
			q->mode = dd_word;
			return 2;
		case 4:
			q->mode = dd_long;
			return 4;
		default:
			q->mode = dd_byte;
			return 0;
	}
}
/* Aggregate bits */
int agbits(int size, long value)
/*
 * ombine bit declarations into a bit field
 */
{
	long rv = 0;
	if (cursize != -1 && (size != cursize || bits == -1 || (bits != -1 &&startbit==0))) {
		rv = agflush(cursize,totbits);
		cursize = -1;
		totbits = 0;
	}
	if (bits != -1) {
		totbits |= (value & bittab[bits-1]) << startbit;
		cursize = size;
	}
	else {
		if (size != -1)
			rv+= agflush(size,value);
		cursize = -1;
		totbits = 0;
	}
	startbit = -1;
	return(rv);
}
/* Basic type subroutines */
int initfloat(void)
{
	struct decldata *q = *sptr = xalloc(sizeof(struct decldata));
	q->val.f = floatexpr();
	sptr = &(*sptr)->link;
	q->mode = dd_float;
			allocated = TRUE;
			return(4);
}
int initlongdouble(void)
{
	struct decldata *q = *sptr = xalloc(sizeof(struct decldata));
	q->val.f = floatexpr();
	sptr = &(*sptr)->link;
	q->mode = dd_ldouble;
			allocated = TRUE;
			return(stdldoublesize);
}
int initdouble(void)
{
	struct decldata *q = *sptr = xalloc(sizeof(struct decldata));
			allocated = TRUE;
	q->val.f = floatexpr();
	sptr = &(*sptr)->link;
	q->mode = dd_double;
			return(8);
}
int initchar(void)
{       
			long t;
			int rv;
			allocated = TRUE;
			rv = agbits(1,t = intexpr(0));
			if (t < SCHAR_MIN || t > SCHAR_MAX)
				generror(ERR_CONSTTOOLARGE,0,0);
			return rv;
}
int initshort(void)
{   
			long t;
			int rv;
			allocated = TRUE;
			rv = agbits(2,t = intexpr(0));
			if (t < SHRT_MIN || t > SHRT_MAX)
				generror(ERR_CONSTTOOLARGE,0,0);
			return rv;
}
int inituchar(void)
{       
			long t;
			int rv;
			allocated = TRUE;
			rv = agbits(1,t = intexpr(0));
			if (t < 0 || t > UCHAR_MAX)
				generror(ERR_CONSTTOOLARGE,0,0);
			return rv;
}
int initushort(void)
{   
			long t;
			int rv;
			allocated = TRUE;
			rv = agbits(2,t = intexpr(0));
			if (t < 0 || t > USHRT_MAX)
				generror(ERR_CONSTTOOLARGE,0,0);
			return rv;
}
int initlong(void)
{       
			long t;
			int rv;
			allocated = TRUE;
			rv = agbits(4,t = intexpr(0));
			if (t < LONG_MIN || t > LONG_MAX)
				generror(ERR_CONSTTOOLARGE,0,0);
			return rv;
}
int initulong(void)
{   
			long t;
			int rv;
			allocated = TRUE;
			rv = agbits(4,t = intexpr(0));
			if (t < 0 || t > ULONG_MAX)
				generror(ERR_CONSTTOOLARGE,0,0);
			return rv;
}
void getreflvalue(ENODE **node, TYP **tp,int pointer)
/*
 * create a node tree for pointer and references that are going in as data
 */
{
	SYM *sp;
	ENODE *pnode=0;
	sp = 0;
	while (lastst == star) {
		getsym();
		getreflvalue(&pnode,tp,pointer);
		if ((*tp)->type == bt_pointer) {
			*tp = (*tp)->btp;
			pnode = makenode(en_l_ref,pnode,0);
		}
		else {
			generror(ERR_DEREF,0,0);
		}
		*node = pnode;
		return;
	}
	if (lastst == and && pointer) {
		getsym();
		getreflvalue(&pnode,tp,pointer);
		if (!((*tp)->type == bt_ifunc) && !((*tp)->type == bt_func) && !(*tp)->val_flag) {
			TYP *tp1 = maketype(bt_pointer,4);
			tp1->btp = *tp;
			*tp = tp1;
			if (pnode)
				pnode = pnode->v.p[0];
		}
		*node = pnode;
		return;
	}
	if (lastst != id) {
		long temp;
		getsym();
		temp = intexpr(tp);
		(*node) = makenode(en_icon,(char *)temp,0);
		return;
	}
	if ((sp = search(lastid,&gsyms)) == 0) {
		gensymerror(ERR_UNDEFINED,lastid);
		return;
	}
	pnode = makenode(en_nacon,(char *)sp->name,0);
	if (pointer && !sp->tp->val_flag)
		pnode = makenode(en_l_ref,pnode,0);
	*tp = sp->tp;
	getsym();
	while (TRUE) {
		long temp;
		switch(lastst) {
	    case openbr:    /* build a subscript reference */
				getsym();
				temp = intexpr(0);
      	if( (*tp)->type != bt_pointer )
        	generrorexp(ERR_NOPOINTER,0,skm_closebr);
	      else {
  	      (*tp) = (*tp)->btp;
					pnode = makenode(en_add,pnode,makenode(en_icon,(char *)(temp*(*tp)->size),0));
				}
      	needpuncexp(closebr,skm_closebr);
      	break;
      case pointsto:
        if( (*tp)->type != bt_pointer ) {
        	generror(ERR_NOPOINTER,0,0);
					while (lastst == pointsto || lastst == dot) {
						getsym();
						getsym();
					}
					break;
				}
        else {
  	      (*tp) = (*tp)->btp;
					pnode = makenode(en_l_ref,pnode,0);
				}
/*
 *      fall through to dot operation
 */
      case dot:
        getsym();       /* past -> or . */
	      if( lastst != id )
  	      generror(ERR_IDEXPECT,0,0);
    	  else    {
      	  sp = search(lastid,&(*tp)->lst);
        	if( sp == 0 ) {
						(*tp) = &stdmatch;
	          gensymerror(ERR_UNDEFINED,lastid);
						getsym();
						while (lastst == pointsto || lastst == dot) {
							getsym();
							getsym();
						}
					}
  	      else    {
						pnode = makenode(en_add,pnode,makenode(en_icon,(char *)sp->value.i,0));
    	      (*tp) = sp->tp;
      	    getsym();       /* past id */
        	}
        	break;

				}
			case plus:
				getsym();
				pnode = makenode(en_add,pnode,makenode(en_icon,(char *)intexpr(0),0));
				break;
			case minus:
				getsym();
				pnode = makenode(en_add,pnode,makenode(en_icon,(char *)(-intexpr(0)),0));
				break;
			default:
				*node =pnode;
				return;
		}
	}
}
int checkrefeval(ENODE *node)
/*
 * see if a reference node can be evaluated at compile time
 */
{
	switch(node->nodetype) {
		case en_add:
			return(checkrefeval(node->v.p[0]) || checkrefeval(node->v.p[1]));
		case en_l_ref:
			return 1;
		case en_nacon:
		case en_icon:
		case en_lcon:
		case en_lucon:
		case en_iucon:
			return 0;
		default:
			return 1;
	}
}
int refeval(ENODE *one, ENODE **two)
/*
 * compile time evaluation of references and pointers */
{
	while (1) {
		switch (one->nodetype) {
			case en_add:
				return(refeval(one->v.p[0],two) + refeval(one->v.p[1],two));
			case en_icon:
			case en_lcon:
			case en_lucon:
			case en_iucon:
				return(one->v.i);
			case en_nacon:
				*two = one;
				return 0;
			default:
				return 0;
		}
	}
}
#ifdef CPLUSPLUS
int initref(TYP *tp)
/*
 * init for reference variables
 */
{
	SYM *sp;
	TYP *tp1;
	ENODE *node=0,*node1;
	int ofs;
	allocated = TRUE;
	getreflvalue(&node,&tp1,0);
	if (!node || !checktype(tp,tp1)) {
		genstorage(4);
		generror(ERR_REFLVALUE,0,0);
	}
	else {
		if (!checkrefeval(node)) {
			ofs = refeval(node,&node1);
			sp = search(node1->v.sp,&gsyms);
			makeref(FALSE,sp,ofs);
			sp->tp->uflags |= UF_USED;
		}
		else  {
			node1 = makenode(en_l_ref,makenode(en_nacon,locsp->name,0),0);
			node1 = makenode(en_assign,node1,node);
			cppinitinsert(node1);
			genstorage(4);
		}
	}
	endinit();
	return 4;
}
#endif
int initpointer(void)
{       SYM     *sp;
				ENODE *node=0,*node1;
				TYP *tp1;
				allocated = TRUE;
       	if(lastst == sconst) {
                makelabel();
                }
       	else if(lastst == lsconst) {
                makelabel();
                }
				else if (lastst == iconst || lastst == lconst || lastst == iuconst || lastst == luconst) {
								long temp;
								TYP *tp;
                agflush(4,temp = intexpr(&tp));
								if (temp && (tp->type != bt_pointer && tp->type != bt_ptrfunc))
									generror(ERR_NONPORT,0,0);
				}
				else {
					getreflvalue(&node,&tp1,1);
					if (!node || (tp1->type != bt_pointer && tp1->type != bt_func && tp1->type != bt_ifunc && !tp1->val_flag))
						gensymerror(ERR_NOINIT,locsp->name);
					else {
						if (!checkrefeval(node)) {
							int ofs = refeval(node,&node1);
							sp = search(node1->v.sp,&gsyms);
							if (sp->tp->type == bt_func || sp->tp->type == bt_ifunc) {
  	            makeref(TRUE,sp,ofs);
							}
							else
      	        makeref(FALSE,sp,ofs);
							sp->tp->uflags |= UF_USED;
						}
						else  {
							if (!prm_cplusplus) 
								gensymerror(ERR_NOINIT,locsp->name);
#ifdef CPLUSPLUS
							else {
								node1 = makenode(en_l_ref,makenode(en_nacon,locsp->name,0),0);
								node1 = makenode(en_assign,node1,node);
								cppinitinsert(node1);
							}
#endif
							makestorage(4);
						}
					 }
				}
        endinit();
        return 4;       /* pointers are 4 bytes long */
}
int initpointerfunc(void)
{       SYM     *sp;
				char *nm;
				allocated = TRUE;
        if(lastst == and)     /* address of a variable */
                getsym();
        if(lastst != id) {
								long temp;
								TYP *tp;
                agflush(4,temp = intexpr(&tp));
								if (temp && (tp->type != bt_pointer && tp->type != bt_ptrfunc))
									generror(ERR_NONPORT,0,0);
							endinit();
							return(4);
					 }
        else  {
#ifdef CPLUSPLUS
					if (prm_cplusplus)
						nm = cppmangle(lastid,locsp->tp);
					else
#endif
						nm = lastid;
					if( (sp = gsearch(nm)) == 0)
				 		gensymerror(ERR_UNDEFINED,nm);
        	else
          	getsym();
				}
        makeref(TRUE,sp,0);
				if (sp)
					sp->tp->uflags |= UF_USED;
        endinit();
        return 4;       /* pointers are 4 bytes long */
}
/* Finish init */
void endinit(void)
{       if( lastst != comma && lastst != semicolon && lastst != end) {
                expecttoken(end,0);
                while( lastst != comma && lastst != semicolon && lastst != end && lastst != eof)
                        getsym();
                }
}