[analyzer] Overhaul how the static analyzer expects CFGs by forcing CFGs to be linearized only when used by the static analyzer. This required a rewrite of LiveVariables, and exposed a ton of subtle bugs.

The motivation of this large change is to drastically simplify the logic in ExprEngine going forward.

Some fallout is that the output of some BugReporterVisitors is not as accurate as before; those will
need to be fixed over time.  There is also some possible performance regression as RemoveDeadBindings
will be called frequently; this can also be improved over time.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@136419 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 0 insertions, 23 deletions

diff --git a/lib/StaticAnalyzer/Core/Environment.cpp b/lib/StaticAnalyzer/Core/Environment.cpp
index 4a2d33d8d3..92c4a4c581 100644
--- a/lib/StaticAnalyzer/Core/Environment.cpp
+++ b/lib/StaticAnalyzer/Core/Environment.cpp
@@ -158,8 +158,6 @@ EnvironmentManager::removeDeadBindings(Environment Env,
                                        const GRState *ST,
                               SmallVectorImpl<const MemRegion*> &DRoots) {
 
-  CFG &C = *SymReaper.getLocationContext()->getCFG();
-
   // We construct a new Environment object entirely, as this is cheaper than
   // individually removing all the subexpression bindings (which will greatly
   // outnumber block-level expression bindings).
@@ -172,7 +170,6 @@ EnvironmentManager::removeDeadBindings(Environment Env,
        I != E; ++I) {
 
     const Stmt *BlkExpr = I.getKey();
-    
     // For recorded locations (used when evaluating loads and stores), we
     // consider them live only when their associated normal expression is
     // also live.
@@ -182,28 +179,8 @@ EnvironmentManager::removeDeadBindings(Environment Env,
       deferredLocations.push_back(std::make_pair(BlkExpr, I.getData()));
       continue;
     }
-    
     const SVal &X = I.getData();
 
-    // Block-level expressions in callers are assumed always live.
-    if (isBlockExprInCallers(BlkExpr, SymReaper.getLocationContext())) {
-      NewEnv.ExprBindings = F.add(NewEnv.ExprBindings, BlkExpr, X);
-
-      if (isa<loc::MemRegionVal>(X)) {
-        const MemRegion* R = cast<loc::MemRegionVal>(X).getRegion();
-        DRoots.push_back(R);
-      }
-
-      // Mark all symbols in the block expr's value live.
-      MarkLiveCallback cb(SymReaper);
-      ST->scanReachableSymbols(X, cb);
-      continue;
-    }
-
-    // Not a block-level expression?
-    if (!C.isBlkExpr(BlkExpr))
-      continue;
-
     if (SymReaper.isLive(BlkExpr)) {
       // Copy the binding to the new map.
       NewEnv.ExprBindings = F.add(NewEnv.ExprBindings, BlkExpr, X);