Add wormhole.[ch]

right/src/wormhole.c

@@ -0,0 +1,17 @@
+#include "wormhole.h"
+
+wormhole_t *Wormhole NO_INIT_GCC;
+
+void* getSP(void)
+{
+    void *sp;
+//    __asm__ __volatile__ ("mov %0, sp" : "=r"(sp));
+    __asm__ __volatile__ ("mrs %0, msp" : "=r"(sp));
+    return sp;
+}
+
+void __attribute__ ((__section__ (".init3"), __naked__)) move_sp(void) {
+    void* SP = getSP();
+//    SP -= sizeof(wormhole_t);
+    Wormhole = (wormhole_t*)(SP + 1);
+}