PR30711: Fix incorrect profiling of 'long long' in FoldingSet, then use it to
authorRichard Smith <richard-llvm@metafoo.co.uk>
Sun, 16 Oct 2016 17:49:09 +0000 (17:49 +0000)
committerRichard Smith <richard-llvm@metafoo.co.uk>
Sun, 16 Oct 2016 17:49:09 +0000 (17:49 +0000)
fix TBAA violation in profiling of pointers.

llvm-svn: 284336

llvm/lib/Support/FoldingSet.cpp
llvm/unittests/ADT/FoldingSet.cpp

index a27d317..c9bca7f 100644 (file)
@@ -54,8 +54,9 @@ void FoldingSetNodeID::AddPointer(const void *Ptr) {
   // depend on the host. It doesn't matter, however, because hashing on
   // pointer values is inherently unstable. Nothing should depend on the
   // ordering of nodes in the folding set.
-  Bits.append(reinterpret_cast<unsigned *>(&Ptr),
-              reinterpret_cast<unsigned *>(&Ptr+1));
+  static_assert(sizeof(uintptr_t) <= sizeof(unsigned long long),
+                "unexpected pointer size");
+  AddInteger(reinterpret_cast<uintptr_t>(Ptr));
 }
 void FoldingSetNodeID::AddInteger(signed I) {
   Bits.push_back(I);
@@ -80,8 +81,7 @@ void FoldingSetNodeID::AddInteger(long long I) {
 }
 void FoldingSetNodeID::AddInteger(unsigned long long I) {
   AddInteger(unsigned(I));
-  if ((uint64_t)(unsigned)I != I)
-    Bits.push_back(unsigned(I >> 32));
+  AddInteger(unsigned(I >> 32));
 }
 
 void FoldingSetNodeID::AddString(StringRef String) {
index 927ef31..6964638 100644 (file)
@@ -35,6 +35,27 @@ TEST(FoldingSetTest, UnalignedStringTest) {
   EXPECT_EQ(a.ComputeHash(), b.ComputeHash());
 }
 
+TEST(FoldingSetTest, LongLongComparison) {
+  struct LongLongContainer : FoldingSetNode {
+    unsigned long long A, B;
+    LongLongContainer(unsigned long long A, unsigned long long B)
+        : A(A), B(B) {}
+    void Profile(FoldingSetNodeID &ID) const {
+      ID.AddInteger(A);
+      ID.AddInteger(B);
+    }
+  };
+
+  LongLongContainer C1((1ULL << 32) + 1, 1ULL);
+  LongLongContainer C2(1ULL, (1ULL << 32) + 1);
+
+  FoldingSet<LongLongContainer> Set;
+
+  EXPECT_EQ(&C1, Set.GetOrInsertNode(&C1));
+  EXPECT_EQ(&C2, Set.GetOrInsertNode(&C2));
+  EXPECT_EQ(2U, Set.size());
+}
+
 struct TrivialPair : public FoldingSetNode {
   unsigned Key = 0;
   unsigned Value = 0;