Merge pull request #5386 from erik-krogh/cachePrepend

codeql-ci · web-flow · commit b37da7cc22c3 · 2021-03-16T05:49:24.000-07:00
Approved by asgerf
diff --git a/javascript/ql/src/semmle/javascript/dataflow/TypeTracking.qll b/javascript/ql/src/semmle/javascript/dataflow/TypeTracking.qll
@@ -9,6 +9,7 @@
 private import javascript
 private import internal.FlowSteps
 private import internal.StepSummary
+private import semmle.javascript.internal.CachedStages
 
 private newtype TTypeTracker = MkTypeTracker(Boolean hasCall, OptionalPropertyName prop)
 
@@ -51,7 +52,9 @@ class TypeTracker extends TTypeTracker {
   /** Gets the summary resulting from appending `step` to this type-tracking summary. */
   cached
   TypeTracker append(StepSummary step) {
-    step = LevelStep() and result = this
+    Stages::TypeTracking::ref() and
+    step = LevelStep() and
+    result = this
     or
     exists(string toProp | step = LoadStoreStep(prop, toProp) |
       result = MkTypeTracker(hasCall, toProp)
@@ -214,8 +217,11 @@ class TypeBackTracker extends TTypeBackTracker {
   TypeBackTracker() { this = MkTypeBackTracker(hasReturn, prop) }
 
   /** Gets the summary resulting from prepending `step` to this type-tracking summary. */
+  cached
   TypeBackTracker prepend(StepSummary step) {
-    step = LevelStep() and result = this
+    Stages::TypeTracking::ref() and
+    step = LevelStep() and
+    result = this
     or
     exists(string fromProp | step = LoadStoreStep(fromProp, prop) |
       result = MkTypeBackTracker(hasReturn, fromProp)
diff --git a/javascript/ql/src/semmle/javascript/internal/CachedStages.qll b/javascript/ql/src/semmle/javascript/internal/CachedStages.qll
@@ -181,6 +181,10 @@ module Stages {
       PreCallGraphStep::loadStep(_, _, _)
       or
       basicLoadStep(_, _, _)
+      or
+      exists(any(DataFlow::TypeTracker t).append(_))
+      or
+      exists(any(DataFlow::TypeBackTracker t).prepend(_))
     }
   }
 

Original file line number	Diff line number	Diff line change
`@@ -181,6 +181,10 @@ module Stages {`
`181`	`181`	`PreCallGraphStep::loadStep(_, _, _)`
`182`	`182`	`or`
`183`	`183`	`basicLoadStep(_, _, _)`
	`184`	`+ or`
	`185`	`+ exists(any(DataFlow::TypeTracker t).append(_))`
	`186`	`+ or`
	`187`	`+ exists(any(DataFlow::TypeBackTracker t).prepend(_))`
`184`	`188`	`}`
`185`	`189`	`}`
`186`	`190`