util.cpp

c的简化编译器

/****************************************************/
/* File: util.c                                     */
/* Main program for c- compiler                     */
/* Compiler Construction: Principles and Practice   */
/* Maker:Liukai                                     */
/****************************************************/

#include "globals.h"
#include "util.h"

/* Procedure printToken prints a token 
 * and its lexeme to the listing file
 */
void printToken( TokenType token, const char* tokenString )
{ switch (token)
  { case IF:
    case ELSE:
    case WHILE:
    case INT:
    case RETURN:
    case VOID:
      fprintf(listing,
         "reserved word: %s\n",tokenString);
      break;
    case ASSIGN: fprintf(listing,"=\n"); break;
    case EQ: fprintf(listing,"==\n"); break;
	case NEQ: fprintf(listing,"!=\n"); break;
	case LT: fprintf(listing,"<\n"); break;
	case PLUS: fprintf(listing,"+\n"); break;
	case MINUS: fprintf(listing,"-\n"); break;
    case TIMES: fprintf(listing,"*\n"); break;
    case OVER: fprintf(listing,"/\n"); break;
	case LPAREN: fprintf(listing,"(\n"); break;
    case RPAREN: fprintf(listing,")\n"); break;
    case SEMI: fprintf(listing,";\n"); break;
	case DOUHAO: fprintf(listing,",\n"); break;
	case ZLPAREN: fprintf(listing,"[\n"); break;
	case ZRPAREN: fprintf(listing,"]\n"); break;
	case DLPAREN: fprintf(listing,"{\n"); break;
	case DRPAREN: fprintf(listing,"}\n"); break;
	case MT: fprintf(listing,">\n"); break;
	case LET: fprintf(listing,"<=\n"); break;
	case MET: fprintf(listing,">=\n"); break;
    case ENDFILE: fprintf(listing,"EOF\n"); break;
    case NUM:
      fprintf(listing,
          "NUM, val= %s\n",tokenString);
      break;
    case ID:
      fprintf(listing,
          "ID, name= %s\n",tokenString);
      break;
    case ERROR:
      fprintf(listing,
          "ERROR: %s\n",tokenString);
      break;
    default: /* should never happen */
      fprintf(listing,"Unknown token: %d\n",token);
  }
}

/* Function newStmtNode creates a new statement
 * node for syntax tree construction
 */
TreeNode *newStmtNode(StmtKind Kind)
{
	TreeNode *t=(TreeNode *)malloc(sizeof(TreeNode));
	int i;
	if (t==NULL)
	{
		fprintf(listing,"out of memory error at line %d\n",lineno);
	}
	else
	{
		for (i=0;i<3 ;i++ )
		{
			t->child[i]=NULL;
		}
		t->sibling=NULL;
		t->nodeKind=StmtK;
		t->Kind.stmt=Kind;
		t->lineno=lineno;

	}
	return t;
}
/*TreeNode * newStmtNode(StmtKind Kind)
{ TreeNode * t = (TreeNode *) malloc(sizeof(TreeNode));
  int i;
  if (t==NULL)
    fprintf(listing,"Out of memory error at line %d\n",lineno);
  else {
    for (i=0;i<MAXCHILDREN;i++) t->child[i] = NULL;
    t->sibling = NULL;
    t->nodeKind = StmtK;
    t->Kind.stmt = Kind;
    t->lineno = lineno;
  }
  return t;
}*/

/* Function newExpNode creates a new expression 
 * node for syntax tree construction
 */
TreeNode *newExpNode(ExpKind Kind)
{
	TreeNode *t=(TreeNode *) malloc(sizeof(TreeNode));
	int i;
	if (t==NULL)
	{
		fprintf(listing,"out of memory error at line %d\n",lineno);
	}
	else
	{
		for (i=0;i<3 ;i++ )
		{
			t->child[i]=NULL;
		}
		t->sibling=NULL;
		t->nodeKind=ExpK;
		t->Kind.exp=Kind;
		t->lineno=lineno;
		t->type=Void;
		t->idtype1=VarK;
	
		t->is=no;
	}
	return t;
}
 /*
TreeNode * newExpNode(ExpKind Kind)
{ TreeNode * t = (TreeNode *) malloc(sizeof(TreeNode));
  int i;
  if (t==NULL)
    fprintf(listing,"Out of memory error at line %d\n",lineno);
  else {
    for (i=0;i<MAXCHILDREN;i++) t->child[i] = NULL;
    t->sibling = NULL;
    t->nodeKind = ExpK;
    t->Kind.exp = Kind;
    t->lineno = lineno;
    t->type = Void;
  }
  return t;
}*/

/* Function copyString allocates and makes a new
 * copy of an existing string
 */
char * copyString(char *s)
{
	int n;
	char *t;
	if (s==NULL)
	{
		return NULL;
	}
	n=strlen(s)+1;
	t=new char(n);
	if (t==NULL)
	{
		fprintf(listing,"out of memory error at line %d\n",lineno);
	}
	else strcpy(t,s);
	return t;
}
 /*
char * copyString(char * s)
{ int n;
  char * t;
  if (s==NULL) return NULL;
  n = strlen(s)+1;
  t = new char(n);
  if (t==NULL)
    fprintf(listing,"Out of memory error at line %d\n",lineno);
  else strcpy(t,s);
  return t;
}*/

/* Variable indentno is used by printTree to
 * store current number of spaces to indent
 */
static indentno = 0;

/* macros to increase/decrease indentation */
#define INDENT indentno+=2
#define UNINDENT indentno-=2

/* printSpaces indents by printing spaces */
static void printSpaces(void)
{ int i;
  for (i=0;i<indentno;i++)
    fprintf(listing," ");
}

/* procedure printTree prints a syntax tree to the 
 * listing file using indentation to indicate subtrees
 */
void printTree( TreeNode * tree )
{ int i;
  INDENT;
  while (tree != NULL) {
    printSpaces();
    if (tree->nodeKind==StmtK)
    { switch (tree->Kind.stmt) {
        case IfK:
          fprintf(listing,"If\n");
          break;
        case WhileK:
          fprintf(listing,"While\n");
          break;
        case AssignK:
          fprintf(listing,"Assign\n");
          break;
        case ReturnK:
          fprintf(listing,"Return\n");
          break;
		case CompoundK:
          fprintf(listing,"Compound\n");
          break;
        /*case VoidK:
			fprintf(listing,"Void\n");
			break;
		case IntK:
			fprintf(listing,"Int\n");
			break;*/
        default:
			fprintf(listing,"Unknown ExpNode Kind\n");
          break;
      }
    }
    else if (tree->nodeKind==ExpK)
    { switch (tree->Kind.exp) {
        case OpK:
          fprintf(listing,"Op: ");
          printToken(tree->attr.op,"\0");
          break;
        case ConstK:
          fprintf(listing,"Constno: %d\n",tree->attr.val);
          break;
        case IdK:
          fprintf(listing,"Id: %s\n",tree->attr.name);
          break;
        default:
          fprintf(listing,"Unknown ExpNode Kind\n");
          break;
      }
    }
    else fprintf(listing,"Unknown node Kind\n");
    for (i=0;i<3;i++)
         printTree(tree->child[i]);
    tree = tree->sibling;
  }
  UNINDENT;
}