組譯器(2)

攥寫簡易的組譯器

#include

<
stdio.h
>

#include 
<
stdlib.h
>

#include 
<
string.h
>

typedef char* string;
typedef struct _Pair {
string key;
void *value;
} Pair;
string h2b[] = {
"0000", "0001", "0010", "0011",
"0100", "0101", "0110", "0111", 
"1000", "1001", "1010", "1011",
"1100", "1101", "1110", "1111"};
void hex2binary(string hex, string binary) {
for (int i=0; hex[i] != '\0'; i++) {
char h = hex[i] - '0';
if (h 
>
 10) h = hex[i] - 'A' + 10;
sprintf(
&
binary[4*i], "%s", h2b[h]);
}
}
void decimal2binary(int d, string binary) {
char hex[100];
sprintf(hex, "%04x", d);
hex2binary(hex, binary); 
}
Pair dMap[] = {
{"", "000"}, {"M", "001"}, {"D", "010"}, {"MD", "011"},
{"A","100"}, {"AM","101"}, {"AD","110"}, {"AMD","111"}
};
Pair cMap[] = {
{"0", "0101010"}, {"1", "0111111"}, {"-1", "0111010"},
{"D", "0001100"}, {"A", "0110000"}, {"!D", "0001101"},
{"!A", "0110001"}, {"-D", "0001111"}, {"-A", "0110011"},
{"D+1", "0011111"}, {"A+1", "0110111"}, {"D-1", "0001110"},
{"A-1", "0110010"}, {"D+A", "0000010"}, {"D-A", "0010011"},
{"A-D", "0000111"}, {"D
&
A", "0000000"}, {"D|A", "0010101"},
{"M", "1110000"}, {"!M", "1110001"}, {"-M", "1110011"},
{"M+1", "1110111"}, {"M-1", "1110010"}, {"D+M", "1000010"},
{"D-M", "1010011"}, {"M-D", "1000111"}, {"D
&
M", "1000000"},
{"D|M", "1010101"}
};
Pair jMap[] = {
{"", "000"}, {"JGT", "001"}, {"JEQ", "010"}, {"JGE", "011"},
{"JLT", "100"}, {"JNE", "101"}, {"JLE", "110"}, {"JMP", "111"}
};
#define arraySize(array) (sizeof(array)/sizeof(array[0]))
int find(string key, Pair map[], int len) {
for (int i=0; i
<
len; i++) {
if (strcmp(map[i].key, key)==0)
return i;
}
return -1;
}
string lookup(string key, Pair map[], int len) {
int i = find(key, map, len);
if (i==-1) return NULL;
return map[i].value;
}
void code2binary(string code, string binary) {
if (code[0]=='@') { // A 指令： ＠number
int number;
sscanf(code, "@%d", 
&
number);
decimal2binary(number, binary); 
}else if (code[1]==';'){ //j 指令 : @number1
int number1;
sscanf(code, ";%d", 
&
number1);
decimal2binary(number1, binary); 
}else { // C 指令： d = comp
char d[10], comp[100], j[10];
sscanf(code, "%[^=]=%s=%[^=]=", d, comp, j);
string dcode = lookup(d, dMap, arraySize(dMap));
string ccode = lookup(comp, cMap, arraySize(cMap));
string jcode = lookup(j, jMap, arraySize(jMap));
sprintf(binary, "111%s%s%s", ccode, dcode, jcode);
}
}
void assemble(string fname) {
char infile[100], line[100], binary[17];
sprintf(infile, "%s.asm", fname);
FILE *fp = fopen(infile, "r");
while (fgets(line, sizeof(line), fp)) {
char code[100];
sscanf(line, "%[^/\n\r]", code);
if (strlen(code)==0) continue;
code2binary(code, binary);
printf("%s\n", binary);
}
fclose(fp);
}
// run: ./asm Add 
>
 Add.hack
int main(int argc, char *argv[]) {
assemble(argv[1]);
}