[analyzer] introduce getSVal(Stmt *) helper on ExplodedNode, make sure the helper is used consistently

In most cases using
`N->getState()->getSVal(E, N->getLocationContext())`
is ugly, verbose, and also opens up more surface area for bugs if an
inconsistent location context is used.

This patch introduces a helper on an exploded node, and ensures
consistent usage of either `ExplodedNode::getSVal` or
`CheckContext::getSVal` across the codebase.
As a result, a large number of redundant lines is removed.

Differential Revision: https://reviews.llvm.org/D42155

llvm-svn: 322753

1 files changed, 1 insertions, 2 deletions

diff --git a/clang/lib/StaticAnalyzer/Checkers/UndefinedAssignmentChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/UndefinedAssignmentChecker.cpp
index c3dcf1fac19..52b4ca7d770 100644
--- a/clang/lib/StaticAnalyzer/Checkers/UndefinedAssignmentChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/UndefinedAssignmentChecker.cpp
@@ -70,8 +70,7 @@ void UndefinedAssignmentChecker::checkBind(SVal location, SVal val,
 
     if (const BinaryOperator *B = dyn_cast<BinaryOperator>(StoreE)) {
       if (B->isCompoundAssignmentOp()) {
-        ProgramStateRef state = C.getState();
-        if (state->getSVal(B->getLHS(), C.getLocationContext()).isUndef()) {
+        if (C.getSVal(B->getLHS()).isUndef()) {
           str = "The left expression of the compound assignment is an "
                 "uninitialized value. The computed value will also be garbage";
           ex = B->getLHS();