Add tacle jfdctint experiment results

targets/syscalls.c

@@ -4,32 +4,43 @@
 extern char _end; /* provided by linker script */
 static char *heap_ptr = &_end;
 
+// Required for Newlib's malloc/calloc/realloc.
+// Although AOT/Interp use wasm_runtime_malloc instead,
+// it's still necessary for snprintf/vsnprintf.
 void *sbrk(int incr) {
   char *prev = heap_ptr;
   heap_ptr += incr;
   return prev;
 }
 
-int write(int fd, const char *buf, int len) { return len; }
-
+// Required to exist for AOT/Interp, but don't need to be implemented.
+// We don't have files/consoles/serial ports/whatever.
 int read(int fd, char *buf, int len) { return 0; }
+int write(int fd, const char *buf, int len) { return len; }
 int close(int fd) { return -1; }
 int fstat(int fd, struct stat *st) {
   st->st_mode = S_IFCHR;
   return 0;
 }
 int isatty(int fd) { return 1; }
+
+// Required to exist for C/AOT/Interp
 int lseek(int fd, int offset, int whence) { return 0; }
+
+// Required to exist for AOT/Interp.
+// We don't have processes, so those can be stubs.
 void _exit(int status) {
   while (1)
     ;
 }
-void exit(int status) {
-  while (1)
-    ;
-}
 int kill(int pid, int sig) {
   errno = EINVAL;
   return -1;
 }
 int getpid(void) { return 1; }
+
+// Not required? Why do I have this?
+// void exit(int status) {
+//   while (1)
+//     ;
+// }