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#include <stdio.h>
#include <lightning.h>
static jit_state_t *_jit;
typedef int (*pifi)(int); /* Pointer to Int Function of Int */
int main(int argc, char *argv[])
{
pifi fib;
jit_node_t *label;
jit_node_t *call;
jit_node_t *in; /* offset of the argument */
jit_node_t *ref; /* to patch the forward reference */
jit_node_t *zero; /* to patch the forward reference */
init_jit(argv[0]);
_jit = jit_new_state();
label = jit_label();
jit_prolog ();
in = jit_arg ();
jit_getarg (JIT_R0, in); /* R0 = n */
zero = jit_beqi (JIT_R0, 0);
jit_movr (JIT_V0, JIT_R0); /* V0 = R0 */
jit_movi (JIT_R0, 1);
ref = jit_blei (JIT_V0, 2);
jit_subi (JIT_V1, JIT_V0, 1); /* V1 = n-1 */
jit_subi (JIT_V2, JIT_V0, 2); /* V2 = n-2 */
jit_prepare();
jit_pushargr(JIT_V1);
call = jit_finishi(NULL);
jit_patch_at(call, label);
jit_retval(JIT_V1); /* V1 = fib(n-1) */
jit_prepare();
jit_pushargr(JIT_V2);
call = jit_finishi(NULL);
jit_patch_at(call, label);
jit_retval(JIT_R0); /* R0 = fib(n-2) */
jit_addr(JIT_R0, JIT_R0, JIT_V1); /* R0 = R0 + V1 */
jit_patch(ref); /* patch jump */
jit_patch(zero); /* patch jump */
jit_retr(JIT_R0);
/* call the generated code, passing 32 as an argument */
fib = jit_emit();
jit_clear_state();
printf("fib(%d) = %d\n", 32, fib(32));
jit_destroy_state();
finish_jit();
return 0;
}
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