diff --git a/crypto/bn/bn_gf2m.c b/crypto/bn/bn_gf2m.c
index 287adf305a08850fa2b01c4f2e1cb2678d4fdfcb..0fc4460da8006e59118aba3134ed6b1d1801bfcd 100644
--- a/crypto/bn/bn_gf2m.c
+++ b/crypto/bn/bn_gf2m.c
@@ -22,30 +22,32 @@
  */
 # define MAX_ITERATIONS 50
 
-static const BN_ULONG SQR_tb[16] = { 0, 1, 4, 5, 16, 17, 20, 21,
-    64, 65, 68, 69, 80, 81, 84, 85
-};
+# define SQR_nibble(w)   ((((w) & 8) << 3) \
+                       |  (((w) & 4) << 2) \
+                       |  (((w) & 2) << 1) \
+                       |   ((w) & 1))
+
 
 /* Platform-specific macros to accelerate squaring. */
 # if defined(SIXTY_FOUR_BIT) || defined(SIXTY_FOUR_BIT_LONG)
 #  define SQR1(w) \
-    SQR_tb[(w) >> 60 & 0xF] << 56 | SQR_tb[(w) >> 56 & 0xF] << 48 | \
-    SQR_tb[(w) >> 52 & 0xF] << 40 | SQR_tb[(w) >> 48 & 0xF] << 32 | \
-    SQR_tb[(w) >> 44 & 0xF] << 24 | SQR_tb[(w) >> 40 & 0xF] << 16 | \
-    SQR_tb[(w) >> 36 & 0xF] <<  8 | SQR_tb[(w) >> 32 & 0xF]
+    SQR_nibble((w) >> 60) << 56 | SQR_nibble((w) >> 56) << 48 | \
+    SQR_nibble((w) >> 52) << 40 | SQR_nibble((w) >> 48) << 32 | \
+    SQR_nibble((w) >> 44) << 24 | SQR_nibble((w) >> 40) << 16 | \
+    SQR_nibble((w) >> 36) <<  8 | SQR_nibble((w) >> 32)
 #  define SQR0(w) \
-    SQR_tb[(w) >> 28 & 0xF] << 56 | SQR_tb[(w) >> 24 & 0xF] << 48 | \
-    SQR_tb[(w) >> 20 & 0xF] << 40 | SQR_tb[(w) >> 16 & 0xF] << 32 | \
-    SQR_tb[(w) >> 12 & 0xF] << 24 | SQR_tb[(w) >>  8 & 0xF] << 16 | \
-    SQR_tb[(w) >>  4 & 0xF] <<  8 | SQR_tb[(w)       & 0xF]
+    SQR_nibble((w) >> 28) << 56 | SQR_nibble((w) >> 24) << 48 | \
+    SQR_nibble((w) >> 20) << 40 | SQR_nibble((w) >> 16) << 32 | \
+    SQR_nibble((w) >> 12) << 24 | SQR_nibble((w) >>  8) << 16 | \
+    SQR_nibble((w) >>  4) <<  8 | SQR_nibble((w)      )
 # endif
 # ifdef THIRTY_TWO_BIT
 #  define SQR1(w) \
-    SQR_tb[(w) >> 28 & 0xF] << 24 | SQR_tb[(w) >> 24 & 0xF] << 16 | \
-    SQR_tb[(w) >> 20 & 0xF] <<  8 | SQR_tb[(w) >> 16 & 0xF]
+    SQR_nibble((w) >> 28) << 24 | SQR_nibble((w) >> 24) << 16 | \
+    SQR_nibble((w) >> 20) <<  8 | SQR_nibble((w) >> 16)
 #  define SQR0(w) \
-    SQR_tb[(w) >> 12 & 0xF] << 24 | SQR_tb[(w) >>  8 & 0xF] << 16 | \
-    SQR_tb[(w) >>  4 & 0xF] <<  8 | SQR_tb[(w)       & 0xF]
+    SQR_nibble((w) >> 12) << 24 | SQR_nibble((w) >>  8) << 16 | \
+    SQR_nibble((w) >>  4) <<  8 | SQR_nibble((w)      )
 # endif
 
 # if !defined(OPENSSL_BN_ASM_GF2m)