aboutsummaryrefslogtreecommitdiff
path: root/lib/Analysis/UninitializedValues.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'lib/Analysis/UninitializedValues.cpp')
-rw-r--r--lib/Analysis/UninitializedValues.cpp19
1 files changed, 9 insertions, 10 deletions
diff --git a/lib/Analysis/UninitializedValues.cpp b/lib/Analysis/UninitializedValues.cpp
index d5c697aa1c..2116e505d5 100644
--- a/lib/Analysis/UninitializedValues.cpp
+++ b/lib/Analysis/UninitializedValues.cpp
@@ -58,13 +58,15 @@ class VISIBILITY_HIDDEN TransferFuncs
UninitializedValues::ValTy V;
UninitializedValues::AnalysisDataTy& AD;
public:
- TransferFuncs(UninitializedValues::AnalysisDataTy& ad) : AD(ad) {
- V.resetValues(AD);
- }
+ TransferFuncs(UninitializedValues::AnalysisDataTy& ad) : AD(ad) {}
UninitializedValues::ValTy& getVal() { return V; }
CFG& getCFG() { return AD.getCFG(); }
+ void SetTopValue(UninitializedValues::ValTy& X) {
+ X.resetValues(AD);
+ }
+
bool VisitDeclRefExpr(DeclRefExpr* DR);
bool VisitBinaryOperator(BinaryOperator* B);
bool VisitUnaryOperator(UnaryOperator* U);
@@ -76,7 +78,7 @@ public:
bool Visit(Stmt *S);
bool BlockStmt_VisitExpr(Expr* E);
- void VisitTerminator(Stmt* T) { Visit(T); }
+ void VisitTerminator(Stmt* T) { }
BlockVarDecl* FindBlockVarDecl(Stmt* S);
};
@@ -216,12 +218,9 @@ bool TransferFuncs::BlockStmt_VisitExpr(Expr* E) {
// In our transfer functions we take the approach that any
// combination of unintialized values, e.g. Unitialized + ___ = Unitialized.
//
-// Merges take the opposite approach.
-//
-// In the merge of dataflow values we prefer unsoundness, and
-// prefer false negatives to false positives. At merges, if a value for a
-// tracked Decl is EVER initialized in any of the predecessors we treat it as
-// initialized at the confluence point.
+// Merges take the same approach, preferring soundness. At a confluence point,
+// if any predecessor has a variable marked uninitialized, the value is
+// uninitialized at the confluence point.
//===----------------------------------------------------------------------===//
namespace {