rename ReDoSUtil to NfaUtils, and rename the "performance" folder to "regexp"

python/ql/lib/semmle/python/security/BadTagFilterQuery.qll

@@ -2,7 +2,7 @@
  * Provides precicates for reasoning about bad tag filter vulnerabilities.
  */
 
-import performance.RegexpMatching
+import regexp.RegexpMatching
 
 /**
  * Holds if the regexp `root` should be tested against `str`.

python/ql/lib/semmle/python/security/regexp/ExponentialBackTracking.qll

@@ -62,7 +62,7 @@
  *     a suffix `x` (possible empty) that is most likely __not__ accepted.
  */
 
-import ReDoSUtil
+import NfaUtils
 
 /**
  * Holds if state `s` might be inside a backtracking repetition.

python/ql/lib/semmle/python/security/regexp/NfaUtils.qll

@@ -1,18 +1,13 @@
 /**
- * Provides classes for working with regular expressions that can
- * perform backtracking in superlinear/exponential time.
+ * Provides classes and predicates for constructing an NFA from
+ * a regular expression, and various utilities for reasoning about
+ * the resulting NFA.
  *
- * This module contains a number of utility predicates for compiling a regular expression into a NFA and reasoning about this NFA.
- *
- * The `ReDoSConfiguration` contains a `isReDoSCandidate` predicate that is used to
- * to determine which states the prefix/suffix search should happen on.
- * There is only meant to exist one `ReDoSConfiguration` at a time.
- *
- * The predicate `hasReDoSResult` outputs a de-duplicated set of
- * states that will cause backtracking (a rejecting suffix exists).
+ * These utilities are used both by the ReDoS queries and by
+ * other queries that benefit from reasoning about NFAs.
  */
 
-import ReDoSUtilSpecific
+import NfaUtilsSpecific
 
 /**
  * Gets the char after `c` (from a simplified ASCII table).

python/ql/lib/semmle/python/security/regexp/NfaUtilsSpecific.qll

@@ -1,5 +1,5 @@
 /**
- * Provides Python-specific definitions for use in the ReDoSUtil module.
+ * Provides Python-specific definitions for use in the NfaUtils module.
  */
 
 import python

python/ql/lib/semmle/python/security/regexp/RegexpMatching.qll

@@ -3,7 +3,7 @@
  * and for testing which capture groups are filled when a particular regexp matches a string.
  */
 
-import ReDoSUtil
+import NfaUtils
 
 /** A root term */
 class RootTerm extends RegExpTerm {

python/ql/lib/semmle/python/security/regexp/SuperlinearBackTracking.qll

@@ -3,7 +3,7 @@
  * perform backtracking in superlinear time.
  */
 
-import ReDoSUtil
+import NfaUtils
 
 /*
  * This module implements the analysis described in the paper:

python/ql/src/Security/CWE-730/PolynomialReDoS.ql

@@ -13,7 +13,7 @@
  */
 
 import python
-import semmle.python.security.performance.SuperlinearBackTracking
+import semmle.python.security.regexp.SuperlinearBackTracking
 import semmle.python.security.dataflow.PolynomialReDoSQuery
 import DataFlow::PathGraph
 

python/ql/src/Security/CWE-730/ReDoS.ql

@@ -14,7 +14,7 @@
  */
 
 import python
-import semmle.python.security.performance.ExponentialBackTracking
+import semmle.python.security.regexp.ExponentialBackTracking
 
 from RegExpTerm t, string pump, State s, string prefixMsg
 where

python/ql/test/query-tests/Security/CWE-730-PolynomialReDoS/PolynomialBackTracking.ql

@@ -1,5 +1,5 @@
 import python
-import semmle.python.security.performance.SuperlinearBackTracking
+import semmle.python.security.regexp.SuperlinearBackTracking
 
 from PolynomialBackTrackingTerm t
 select t.getRegex(), t, t.getReason()