codegen.c

一个C语言的编译器

#include <stdlib.h>
#include "globals.h"
#include "parse.h"
#include "symtab.h"

static int label_num = 0;
TreeNode * Fun;

void insert()
{
    fprintf(inter_code,"\tWRITE\tproc\tnear\n");
}
void write()
{
    fprintf(inter_code,"\tWRITE\tproc\tnear\n");
    fprintf(inter_code,"\tMOV\tCX , 10000\n");
	fprintf(inter_code,"\tCMP\tBX , CX\n");
	fprintf(inter_code,"\tJL\tw_label1\n");
	fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
    fprintf(inter_code,"\tMOV\tCX , 1000\n");
    fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
	fprintf(inter_code,"\tMOV\tCX , 100\n");
    fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
	fprintf(inter_code,"\tMOV\tCX , 10\n");
    fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
	fprintf(inter_code,"\tMOV\tCX , 1\n");
    fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
    fprintf(inter_code,"\tJMP\tw_label5\n");
	fprintf(inter_code,"w_label1:\n");
	//----------------------------------------------------
	fprintf(inter_code,"\tMOV\tCX , 1000\n");
	fprintf(inter_code,"\tCMP\tBX , CX\n");
	fprintf(inter_code,"\tJL\tw_label2\n");
	fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
    fprintf(inter_code,"\tMOV\tCX , 100\n");
    fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
	fprintf(inter_code,"\tMOV\tCX , 10\n");
    fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
	fprintf(inter_code,"\tMOV\tCX , 1\n");
    fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
     fprintf(inter_code,"\tJMP\tw_label5\n");
	fprintf(inter_code,"w_label2:\n");
	//----------------------------------------------------
	fprintf(inter_code,"\tMOV\tCX , 100\n");
	fprintf(inter_code,"\tCMP\tBX , CX\n");
	fprintf(inter_code,"\tJL\tw_label3\n");
	fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
	fprintf(inter_code,"\tMOV\tCX , 10\n");
    fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
	fprintf(inter_code,"\tMOV\tCX , 1\n");
    fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
     fprintf(inter_code,"\tJMP\tw_label5\n");
	fprintf(inter_code,"w_label3:\n");
	//----------------------------------------------------
	fprintf(inter_code,"\tMOV\tCX , 10\n");
	fprintf(inter_code,"\tCMP\tBX , CX\n");
	fprintf(inter_code,"\tJL\tw_label4\n");
	fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
	fprintf(inter_code,"\tMOV\tCX , 1\n");
    fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
    fprintf(inter_code,"\tJMP\tw_label5\n");
	fprintf(inter_code,"w_label4:\n");
	//----------------------------------------------------
	fprintf(inter_code,"\tMOV\tCX , 1\n");
	fprintf(inter_code,"\tCALL\tWRITE_SUB\n");
    fprintf(inter_code,"w_label5:\n");
    fprintf(inter_code,"\tRET\n");
	fprintf(inter_code,"\tWRITE\tendp\n\n");
}

void write_sub()
{
	fprintf(inter_code,"\tWRITE_SUB\tproc\tnear\n");
	fprintf(inter_code,"\tMOV\tAX , BX\n");
	fprintf(inter_code,"\tMOV\tDX , 0\n");
	fprintf(inter_code,"\tDIV\tCX\n");
	fprintf(inter_code,"\tMOV\tBX , DX\n");
	fprintf(inter_code,"\tMOV\tDL , AL\n");
	fprintf(inter_code,"\tADD\tDL , '0'\n");
	fprintf(inter_code,"\tMOV\tAH , 02h\n");
	fprintf(inter_code,"\tINT\t21h\n");
	fprintf(inter_code,"\tRET\n");
	fprintf(inter_code,"\tWRITE_SUB\tendp\n\n");
}

void GenLabel(char lab[LABEL_SIZE])      //生成标号的函数
{
	static int i=1;
	char temp[LABEL_SIZE];
	strcpy(lab,"L");
	_itoa(i,temp,10);
	strcat(lab,temp);
	i++;
}

void StackSegment(void)                  //堆栈段
{
	fprintf(inter_code,";*******************************************************\n");
	fprintf(inter_code,"Stack_seg\tsegment\n");
	fprintf(inter_code,"\tdw\t200h dup(?)\n");
	fprintf(inter_code,"Stack_seg_top\tlabel\tword\n");
	fprintf(inter_code,"Stack_seg\tends\n");
}
void DataSegmentBegin(void)              //数据段
{
    fprintf(inter_code,";*******************************************************\n");
	fprintf(inter_code,"Data_seg\tsegment\n");
}

void DataSegmentEnd(void)
{
	fprintf(inter_code,"Data_seg\tends\n");
	fprintf(inter_code,";*******************************************************\n");
}

void CodeSegmentBegin(void)              //代码段
{
	fprintf(inter_code,"Code_seg\tsegment\n");
	fprintf(inter_code,"\tassume\tCS:Code_seg, DS:Data_seg, SS:Stack_seg\n");
}

void CodeSegmentEnd(void)
{
	fprintf(inter_code,"Code_seg\tends\n");
	fprintf(inter_code,"\tend\tstart\n");
	fprintf(inter_code,";*******************************************************\n");
}
//--------------------------------------------------------------------------对不同的变量定义进行处理
void VarDec_ini(char *name, int value)
{
	ValEntry * pEntry = malloc(sizeof(ValEntry));
	Lookup_Var(pTable, pTable ->funEntry, name, pEntry);
	if(pEntry->type==Integer)
    {
		fprintf(inter_code,"%s\tdw\t",pEntry->name);
        fprintf(inter_code,"%d\t\n",value);
	}
	if(pEntry->type==Char)
    {
		int i=0;
		char j;
		fprintf(inter_code,"%s\tdb\t",pEntry->name);
		if(value-64)
        while(i<26)
		{
		  if(i==value-65)
		  {
			  j=(char)('A'+i);
              fprintf(inter_code,"'%c'\t\n",j);
		  }
		  i++;
		}
		i=0;
		if(value-96)
        while(i<26)
		{
		  if(i==value-97)
		  {
			  j=(char)('a'+i);
              fprintf(inter_code,"'%c'\t\n",j);
		  }
		  i++;
		}
	}
}

void VarDec(char *name)//local variable declaration without initial value
{
	ValEntry * pEntry = malloc(sizeof(ValEntry));
	Lookup_Var(pTable, pTable ->funEntry, name, pEntry);
	if(pEntry->type==Integer)
    {
		fprintf(inter_code,"%s\tdw\t",pEntry->name);
        fprintf(inter_code,"?\t\n");
	}
	if(pEntry->type==Char)
    {
		fprintf(inter_code,"%s\tdb\t",pEntry->name);
        fprintf(inter_code,"?\t\n");
	}
}

void ArrDec(char *name, int entitynum)
{
	  ValEntry * pEntry = malloc(sizeof(ValEntry));
	  Lookup_Var(pTable, pTable ->funEntry, name, pEntry);
      if(pEntry->type==Integer)
	  {
	    fprintf(inter_code,"%s\tdw\tdup(",pEntry->name);
		fprintf(inter_code,"%d)\n",entitynum);
	  }
	  if(pEntry->type==Char)
	  {
	    fprintf(inter_code,"%s\tdb\tdup(",pEntry->name);
		fprintf(inter_code,"%d)\n",entitynum);
	  }
}
//------------------------------------------------------------------------------------一些辅助函数
void ent(char *name, int para, int retvalue)
{
	if(!strcmp("main",name)){//main function
		fprintf(inter_code,"start:\n");
		fprintf(inter_code,"\t%s\tproc\tfar\n",name);
		fprintf(inter_code,"\tPUSH\tDS\n");     //DS压栈
		fprintf(inter_code,"\tSUB\tAX , AX\n"); //0压栈
		fprintf(inter_code,"\tPUSH\tAX\n");
		fprintf(inter_code,"\tMOV\tAX , Data_seg\n");
		fprintf(inter_code,"\tMOV\tDS , AX\n");
	}
	//其余函数的输出
	else fprintf(inter_code,"\t%s\tproc\tfar\n",name);//to code file
}

void compound_exit(void)
{
pTable = pTable->parent;
}

void leave(char *name)
{
	fprintf(inter_code,"\t%s\tendp\n",name);
}

void ixa_elem_size(char *name1,int n)
{
	fprintf(inter_code,"\tMOV\tSI , %d\n",n);
	fprintf(inter_code,"\tPOP\t%s[",name1);
    fprintf(inter_code,"SI]\n");
}

void ldl(char value)
{
	fprintf(inter_code,"\tMOV\tAX , %d\n",(int)value);
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void lda(char *name)
{
		fprintf(inter_code,"\tMOV\tAX , %s\n",name);
}

void ldc(int value)
{
	fprintf(inter_code,"\tMOV\tAX , %d\n",value);
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void ldd(int value)
{
	int i=0;
	char j;
	    if(value-64)
        while(i<26)
		{
		  if(i==value-65)
		  {
			  j=(char)('A'+i);
			  fprintf(inter_code,"\tMOV\tAX , '%c'\n",j);
		  }
		  i++;
		}
	  i=0;
		if(value-96)
        while(i<26)
		{
		  if(i==value-97)
		  {
			  j=(char)('a'+i);
              fprintf(inter_code,"\tMOV\tAX , '%c'\n",j);
		  }
		  i++;
		}
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void lod(char *name)
{
   fprintf(inter_code,"\tMOV\tAX , %s\n",name);
   fprintf(inter_code,"\tPUSH\tAX\n");
}

void pop(void)
{
	fprintf(inter_code,"\tPOP\tAX\n");
}

void ret(int r,char * name)
{

	  if(r)
	  {
          fprintf(inter_code,"\tPOP\tDX\n");
	  }	  
	  if(strcmp("main",name))
		  {
			fprintf(inter_code,"\tPOP\tCX\n");
			fprintf(inter_code,"\tPOP\tBX\n");
			fprintf(inter_code,"\tPOP\tAX\n");
		  }
	  fprintf(inter_code,"\tRET\n");
}

void stn(char *name)
{
	fprintf(inter_code,"\tPOP\t%s\n",name);
}
//------------------------------------------------------------算术运算(+,-,*,/(%),++,--,&,|,^,~,<<,>>)
void adi(void)  //对"+"进行翻译的函数
{
	fprintf(inter_code,"\tPOP\tBX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tADD\tAX , BX\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void subi(void) //对"-"进行翻译的函数
{
	fprintf(inter_code,"\tPOP\tBX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tSUB\tAX , BX\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void multi(void)  //对"*"进行翻译的函数
{
	fprintf(inter_code,"\tPOP\tBX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tIMUL\tBX\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void divi(void)  //对"/"进行翻译的函数
{
	fprintf(inter_code,"\tPOP\tBX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
    fprintf(inter_code,"\tCWD\n");
	fprintf(inter_code,"\tIDIV\tBX\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void modi(void)  //对"%"进行翻译的函数
{
	fprintf(inter_code,"\tPOP\tBX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
    fprintf(inter_code,"\tCWD\n");
	fprintf(inter_code,"\tIDIV\tBX\n");
	fprintf(inter_code,"\tPUSH\tDX\n");
}

void inci(void)  //对"++"进行翻译的函数
{ 
    fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tINC\tAX\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void deci(void)  //对"--"进行翻译的函数
{ 
    fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tDEC\tAX\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void b_andi(void)   //对"&"进行翻译的函数
{
	fprintf(inter_code,"\tPOP\tBX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tAND\tAX , BX\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void b_ori(void)   //对"|"进行翻译的函数
{
	fprintf(inter_code,"\tPOP\tBX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tOR\tAX , BX\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void b_xori(void) //对"^"进行翻译的函数
{
    fprintf(inter_code,"\tPOP\tBX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tXOR\tAX , BX\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void b_noti(void)   //对"~"进行翻译的函数
{
    fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tNOT\tAX\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void b_lefti(void) //对"<<"进行翻译的函数
{
    fprintf(inter_code,"\tPOP\tCX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tSHL\tAX , CL\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}

void b_righti(void) //对">>"进行翻译的函数
{
    fprintf(inter_code,"\tPOP\tCX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tSHR\tAX , CL\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
}
//---------------------------------------------------------------------------关系运算(==,>,<,>=,<=,!=)
void equi(void) //对"=="进行翻译的函数
{
	fprintf(inter_code,"\tPOP\tBX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tCMP\tAX , BX\n");
	fprintf(inter_code,"\tJE\tLabel%d\n",label_num);
	fprintf(inter_code,"\tMOV\tAX , 0\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
	fprintf(inter_code,"\tJMP\tLabel%d\n",label_num + 1);
	fprintf(inter_code,"Label%d:",label_num);
	fprintf(inter_code,"\tMOV\tAX , 1\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
	fprintf(inter_code,"Label%d:",label_num + 1);
	label_num += 2;
}

void greater(void)  //对">"进行翻译的函数
{
	fprintf(inter_code,"\tPOP\tBX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tCMP\tAX , BX\n");
	fprintf(inter_code,"\tJG\tLabel%d\n",label_num);
	fprintf(inter_code,"\tMOV\tAX , 0\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
	fprintf(inter_code,"\tJMP\tLabel%d\n",label_num+1);
	fprintf(inter_code,"Label%d:",label_num);
	fprintf(inter_code,"\tMOV\tAX , 1\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
	fprintf(inter_code,"Label%d:",label_num+1);
	label_num += 2;
}

void less(void)  //对"<"进行翻译的函数
{
	fprintf(inter_code,"\tPOP\tBX\n");
	fprintf(inter_code,"\tPOP\tAX\n");
	fprintf(inter_code,"\tCMP\tAX , BX\n");
	fprintf(inter_code,"\tJL\tLabel%d\n",label_num);
	fprintf(inter_code,"\tMOV\tAX , 0\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
	fprintf(inter_code,"\tJMP\tLabel%d\n",label_num+1);
	fprintf(inter_code,"Label%d:",label_num);
	fprintf(inter_code,"\tMOV\tAX , 1\n");
	fprintf(inter_code,"\tPUSH\tAX\n");
	fprintf(inter_code,"Label%d:",label_num+1);
	label_num += 2;
}