Bail out the LiveVariables analysis when the CFG is very large, as

we are encountering some scalability issues with memory usage.   The
appropriate long term fix is to make the analysis more scalable, but
this will at least prevent the analyzer swapping when
analyzing very large functions.

llvm-svn: 159578

2 files changed, 10 insertions, 0 deletions

diff --git a/clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp b/clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
index 3761f9c10a6..44b4e31f03c 100644
--- a/clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
+++ b/clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
@@ -11,6 +11,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "clang/Analysis/Analyses/LiveVariables.h"
 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/Calls.h"
@@ -244,6 +245,11 @@ bool ExprEngine::shouldInlineDecl(const Decl *D, ExplodedNode *Pred) {
   if (isa<CXXConstructorDecl>(D))
     return false;
 
+  // It is possible that the live variables analysis cannot be
+  // run.  If so, bail out.
+  if (!CalleeADC->getAnalysis<RelaxedLiveVariables>())
+    return false;
+
   return true;
 }
 
diff --git a/clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp b/clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
index 05fb0155f13..520a975bda5 100644
--- a/clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
+++ b/clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
@@ -523,6 +523,10 @@ void AnalysisConsumer::ActionExprEngine(Decl *D, bool ObjCGCEnabled,
   if (!Mgr->getCFG(D))
     return;
 
+  // See if the LiveVariables analysis scales.
+  if (!Mgr->getAnalysisDeclContext(D)->getAnalysis<RelaxedLiveVariables>())
+    return;
+
   ExprEngine Eng(*Mgr, ObjCGCEnabled, VisitedCallees, &FunctionSummaries);
 
   // Set the graph auditor.