add nfib example + correct measurement of execution time in DEBUG mode

interpreter/main.c

@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <stdbool.h>
 #include <string.h>
+#include <sys/time.h>
 
 #include "getline.h"
 
@@ -18,7 +19,7 @@ int main ( int argc, char *argv[] )
     init_desc();
     init_prim();
 
-    char* input = "..\\tests\\Braun.bsapl";
+    char* input = "..\\tests\\nfib.bsapl";
     
     if ( argc == 2 )
     {
@@ -62,11 +63,26 @@ int main ( int argc, char *argv[] )
 
     Code* expr = parseTerm(&exprstream);
     
+#ifdef DEBUG
+    struct timeval t1, t2;
+    gettimeofday(&t1, NULL);
+#endif
+    
     Thunk* res = exec(expr, stack_top_a, NULL, true);
     eval(res);
+    
+#ifdef DEBUG
+    gettimeofday(&t2, NULL);
+#endif    
+    
     print(res, true);
 
 #ifdef DEBUG
+    // compute and print the elapsed time in millisec
+    double elapsedTime = (t2.tv_sec - t1.tv_sec) * 1000.0;      // sec to ms
+    elapsedTime += (t2.tv_usec - t1.tv_usec) / 1000.0;   // us to ms
+    
+    printf("\n\nexecution time: %G ms\n", elapsedTime);
     print_stat();
 #endif
 }

interpreter/mem.c

@@ -16,7 +16,7 @@ Thunk* stack_a[STACK_SIZE_A];
 char* heap_start;
 
 void print_stat() {
-    printf("\n\nallocation:\n");
+    printf("\nallocation:\n");
     printf("desc: %d\n", desc_alloc);
     printf("code: %d\n", code_alloc);
     printf("heap: %d (%d thunks)\n", heap_alloc, nr_heap_alloc);

tests/nfib.exp

+[2692537]
\ No newline at end of file

tests/nfib.sapl

+main = example.Start
+example.Start = example.nfib 30
+example.nfib !n_0 = if (lt n_0 2) 1 (add 1 (add (example.nfib (sub n_0 1)) (example.nfib (sub n_0 2))))