limex: implement variable shift NFA engines

Replaces the old LimEx NFA engines, which were specialised for model
size and number of shifts, with a new set of engines that can handle a
variable number of shifts.

src/nfa/limex_internal.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, Intel Corporation
+ * Copyright (c) 2015-2016, Intel Corporation
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -68,6 +68,9 @@
     The value of NFA.stateSize gives the total state size in bytes (the sum of
     all the above).
 
+    Number of shifts should be always greater or equal to 1
+    Number of shifts 0 means that no appropriate NFA engine was found.
+
 */
 
 #ifndef LIMEX_INTERNAL_H
@@ -77,7 +80,8 @@
 #include "repeat_internal.h"
 
 // Constants
-#define MAX_MAX_SHIFT 8      /**< largest maxshift used by a LimEx NFA */
+#define MAX_SHIFT_COUNT 8   /**< largest number of shifts used by a LimEx NFA */
+#define MAX_SHIFT_AMOUNT 16 /**< largest shift amount used by a LimEx NFA */
 
 #define LIMEX_FLAG_COMPRESS_STATE  1 /**< pack state into stream state */
 #define LIMEX_FLAG_COMPRESS_MASKED 2 /**< use reach mask-based compression */
@@ -168,8 +172,10 @@ struct LimExNFA##size { /* MUST align with LimExNFABase */                  \
     u_##size compressMask; /**< switch off before compress */               \
     u_##size exceptionMask;                                                 \
     u_##size repeatCyclicMask;                                              \
-    u_##size shift[MAX_MAX_SHIFT];                                          \
     u_##size zombieMask; /**< zombie if in any of the set states */         \
+    u_##size shift[MAX_SHIFT_COUNT];                                        \
+    u32 shiftCount; /**< number of shift masks used */                      \
+    u8 shiftAmount[MAX_SHIFT_COUNT]; /**< shift amount for each mask */     \
 };
 
 CREATE_NFA_LIMEX(32)