From d4aeb8050a1d0fe47c53a73361c8b0b8ac310f46 Mon Sep 17 00:00:00 2001 From: Ted Kremenek Date: Mon, 2 Jul 2012 20:21:52 +0000 Subject: [PATCH] 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. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159578 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Analysis/LiveVariables.cpp | 5 +++++ lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp | 6 ++++++ lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp | 4 ++++ 3 files changed, 15 insertions(+) diff --git a/lib/Analysis/LiveVariables.cpp b/lib/Analysis/LiveVariables.cpp index ff6607d51a..6e10ac1092 100644 --- a/lib/Analysis/LiveVariables.cpp +++ b/lib/Analysis/LiveVariables.cpp @@ -486,6 +486,11 @@ LiveVariables::computeLiveness(AnalysisDeclContext &AC, if (!cfg) return 0; + // The analysis currently has scalability issues for very large CFGs. + // Bail out if it looks too large. + if (cfg->getNumBlockIDs() > 300000) + return 0; + LiveVariablesImpl *LV = new LiveVariablesImpl(AC, killAtAssign); // Construct the dataflow worklist. Enqueue the exit block as the diff --git a/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp b/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp index 3761f9c10a..44b4e31f03 100644 --- a/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp +++ b/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(D)) return false; + // It is possible that the live variables analysis cannot be + // run. If so, bail out. + if (!CalleeADC->getAnalysis()) + return false; + return true; } diff --git a/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp b/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp index 05fb0155f1..520a975bda 100644 --- a/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp +++ b/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()) + return; + ExprEngine Eng(*Mgr, ObjCGCEnabled, VisitedCallees, &FunctionSummaries); // Set the graph auditor. -- 2.40.0