Merge pull request #1083 from geoffw0/newdelete-perf2

jbj · web-flow · commit 9758164dd606 · 2019-03-12T16:08:46.000+01:00
CPP: Fix NewDelete.qll performance.
diff --git a/cpp/ql/src/Critical/NewDelete.qll b/cpp/ql/src/Critical/NewDelete.qll
@@ -80,6 +80,7 @@ private predicate allocReaches0(Expr e, Expr alloc, string kind) {
   ) or exists(Variable v |
     // alloc via a global
     allocReachesVariable(v, alloc, kind) and
+    strictcount(VariableAccess va | va.getTarget() = v) <= 50 and // avoid very expensive cases 
     e.(VariableAccess).getTarget() = v
   )
 }

Original file line number	Diff line number	Diff line change
`@@ -80,6 +80,7 @@ private predicate allocReaches0(Expr e, Expr alloc, string kind) {`
`80`	`80`	`) or exists(Variable v \|`
`81`	`81`	`// alloc via a global`
`82`	`82`	`allocReachesVariable(v, alloc, kind) and`
	`83`	`+ strictcount(VariableAccess va \| va.getTarget() = v) <= 50 and // avoid very expensive cases`
`83`	`84`	`e.(VariableAccess).getTarget() = v`
`84`	`85`	`)`
`85`	`86`	`}`