[analyzer] Run remove dead bindings right before leaving a function.

This is needed to ensure that we always report issues in the correct
function. For example, leaks are identified when we call remove dead
bindings. In order to make sure we report a callee's leak in the callee,
we have to run the operation in the callee's context.

This change required quite a bit of infrastructure work since:
 - We used to only run remove dead bindings before a given statement;
here we need to run it after the last statement in the function. For
this, we added additional Program Point and special mode in the
SymbolReaper to remove all symbols in context lower than the current
one.
 - The call exit operation turned into a sequence of nodes, which are
now guarded by CallExitBegin and CallExitEnd nodes for clarity and
convenience.

(Sorry for the long diff.)

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@155244 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 7 deletions

diff --git a/lib/StaticAnalyzer/Core/PathDiagnostic.cpp b/lib/StaticAnalyzer/Core/PathDiagnostic.cpp
index 01dd965ac5..a1e662f129 100644
--- a/lib/StaticAnalyzer/Core/PathDiagnostic.cpp
+++ b/lib/StaticAnalyzer/Core/PathDiagnostic.cpp
@@ -510,9 +510,9 @@ static PathDiagnosticLocation getLastStmtLoc(const ExplodedNode *N,
 
 PathDiagnosticCallPiece *
 PathDiagnosticCallPiece::construct(const ExplodedNode *N,
-                                   const CallExit &CE,
+                                   const CallExitEnd &CE,
                                    const SourceManager &SM) {
-  const Decl *caller = CE.getLocationContext()->getParent()->getDecl();
+  const Decl *caller = CE.getLocationContext()->getDecl();
   PathDiagnosticLocation pos = getLastStmtLoc(N, SM);
   return new PathDiagnosticCallPiece(caller, pos);
 }
@@ -667,16 +667,13 @@ StackHintGenerator::~StackHintGenerator() {}
 
 std::string StackHintGeneratorForSymbol::getMessage(const ExplodedNode *N){
   ProgramPoint P = N->getLocation();
-  const CallExit *CExit = dyn_cast<CallExit>(&P);
-  assert(CExit && "Stack Hints should be constructed at CallExit points.");
+  const CallExitEnd *CExit = dyn_cast<CallExitEnd>(&P);
+  assert(CExit && "Stack Hints should be constructed at CallExitEnd points.");
 
   const CallExpr *CE = dyn_cast_or_null<CallExpr>(CExit->getStmt());
   if (!CE)
     return "";
 
-  // Get the successor node to make sure the return statement is evaluated and
-  // CE is set to the result value.
-  N = *N->succ_begin();
   if (!N)
     return getMessageForSymbolNotFound();