124 lines
2.7 KiB
Plaintext
124 lines
2.7 KiB
Plaintext
#include "sylib.h"
|
|
#include "sylib.h"
|
|
// Brainfuck Interpreter
|
|
// Reads program from stdin, interprets and outputs to stdout.
|
|
//
|
|
// Main optimization targets:
|
|
// jump table, inline variables, etc.
|
|
|
|
int program_length = 0;
|
|
int program[65536] = {};
|
|
int tape[65536] = {};
|
|
int input[65536] = {};
|
|
int input_length = 0;
|
|
int output[65536] = {};
|
|
int output_length = 0;
|
|
|
|
int get_bf_char() {
|
|
int get = getch();
|
|
while (get != 62 && get != 60 && get != 43 && get != 45 && get != 91 &&
|
|
get != 93 && get != 46 && get != 44 && get != 35) {
|
|
get = getch();
|
|
}
|
|
return get;
|
|
}
|
|
|
|
void read_program() {
|
|
int get = get_bf_char();
|
|
while (get != 35) {
|
|
program[program_length] = get;
|
|
get = get_bf_char();
|
|
program_length = program_length + 1;
|
|
}
|
|
|
|
// read input
|
|
// input starts with an `i`
|
|
int verify = getch();
|
|
if (verify != 105) {
|
|
return;
|
|
}
|
|
// and a length
|
|
input_length = getint();
|
|
// and a random char
|
|
getch();
|
|
int i = 0;
|
|
while (i < input_length) {
|
|
input[i] = getch();
|
|
i = i + 1;
|
|
}
|
|
}
|
|
|
|
void run_program() {
|
|
int ip = 0;
|
|
int read_head = 0;
|
|
int input_head = 0;
|
|
int return_address[512] = {};
|
|
int return_address_top = 0;
|
|
output_length = 0;
|
|
while (ip < program_length) {
|
|
int code = program[ip];
|
|
if (code == 62) {
|
|
read_head = read_head + 1;
|
|
} else if (code == 60) {
|
|
read_head = read_head - 1;
|
|
} else if (code == 43) {
|
|
tape[read_head] = tape[read_head] + 1;
|
|
} else if (code == 45) {
|
|
tape[read_head] = tape[read_head] - 1;
|
|
} else if (code == 91) {
|
|
int val = tape[read_head];
|
|
if (val != 0) {
|
|
return_address[return_address_top] = ip;
|
|
return_address_top = return_address_top + 1;
|
|
} else {
|
|
// find the matching ]
|
|
int loop = 1;
|
|
while (loop > 0) {
|
|
ip = ip + 1;
|
|
if (program[ip] == 93) {
|
|
loop = loop - 1;
|
|
}
|
|
if (program[ip] == 91) {
|
|
loop = loop + 1;
|
|
}
|
|
}
|
|
}
|
|
} else if (code == 93) {
|
|
int val = tape[read_head];
|
|
if (val == 0) {
|
|
return_address_top = return_address_top - 1;
|
|
} else {
|
|
ip = return_address[return_address_top - 1];
|
|
}
|
|
} else if (code == 46) {
|
|
output[output_length] = tape[read_head];
|
|
output_length = output_length + 1;
|
|
} else if (code == 44) {
|
|
if (input_head >= input_length) {
|
|
tape[read_head] = 0;
|
|
} else {
|
|
tape[read_head] = input[input_head];
|
|
input_head = input_head + 1;
|
|
}
|
|
}
|
|
ip = ip + 1;
|
|
}
|
|
}
|
|
|
|
void output_() {
|
|
int i = 0;
|
|
while (i < output_length) {
|
|
putch(output[i]);
|
|
i = i + 1;
|
|
}
|
|
}
|
|
|
|
int main() {
|
|
read_program();
|
|
starttime();
|
|
run_program();
|
|
stoptime();
|
|
output_();
|
|
return 0;
|
|
}
|