[StaticAnalyzer] LoopUnrolling fixes

1. The LoopUnrolling feature needs the LoopExit included in the CFG so added this
dependency via the config options
2. The LoopExit element can be encountered even if we haven't encountered the
block of the corresponding LoopStmt. So the asserts were not right.
3. If we are caching out the Node then we get a nullptr from generateNode which
case was not handled.


Differential Revision: https://reviews.llvm.org/D37103

1 files changed, 2 insertions, 9 deletions

diff --git a/clang/lib/StaticAnalyzer/Core/LoopUnrolling.cpp b/clang/lib/StaticAnalyzer/Core/LoopUnrolling.cpp
index d9a31ef3eb4..7db628aa077 100644
--- a/clang/lib/StaticAnalyzer/Core/LoopUnrolling.cpp
+++ b/clang/lib/StaticAnalyzer/Core/LoopUnrolling.cpp
@@ -13,15 +13,11 @@
 ///
 //===----------------------------------------------------------------------===//
 
-#include "clang/Analysis/CFGStmtMap.h"
 #include "clang/ASTMatchers/ASTMatchers.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
-#include "clang/AST/ParentMap.h"
-#include "clang/AST/StmtVisitor.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/LoopUnrolling.h"
-#include "llvm/ADT/Statistic.h"
 
 using namespace clang;
 using namespace ento;
@@ -72,11 +68,8 @@ static bool isLoopStmt(const Stmt *S) {
 
 ProgramStateRef processLoopEnd(const Stmt *LoopStmt, ProgramStateRef State) {
   auto LS = State->get<LoopStack>();
-  assert(!LS.isEmpty() && "Loop not added to the stack.");
-  assert(LoopStmt == LS.getHead().getLoopStmt() &&
-         "Loop is not on top of the stack.");
-
-  State = State->set<LoopStack>(LS.getTail());
+  if (!LS.isEmpty() && LS.getHead().getLoopStmt() == LoopStmt)
+    State = State->set<LoopStack>(LS.getTail());
   return State;
 }