dct-test: perform emms before gettime().

This fixes the hypothetical case of a gettime implementation using floats
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/dct-test.c

@@ -351,10 +351,10 @@ static int dct_error(const struct algo *dct, int test, int is_idct, int speed, c
             memcpy(block, block1, sizeof(block));
             dct->func(block);
         }
+        mmx_emms();
         it1 += NB_ITS_SPEED;
         ti1 = gettime() - ti;
     } while (ti1 < 1000000);
-    mmx_emms();
 
     printf("%s %s: %0.1f kdct/s\n", is_idct ? "IDCT" : "DCT", dct->name,
            (double) it1 * 1000.0 / (double) ti1);
@@ -512,10 +512,10 @@ static void idct248_error(const char *name,
                 block[i] = block1[i];
             idct248_put(img_dest, 8, block);
         }
+        mmx_emms();
         it1 += NB_ITS_SPEED;
         ti1 = gettime() - ti;
     } while (ti1 < 1000000);
-    mmx_emms();
 
     printf("%s %s: %0.1f kdct/s\n", 1 ? "IDCT248" : "DCT248", name,
            (double) it1 * 1000.0 / (double) ti1);