Add missing vtable anchor's.

The following description is from http://reviews.llvm.org/D15481:

ICmpInst, GetElementPtrInst and PHINode have no anchor functions. This causes the vtable and the type info (if RTTI is enabled in user code) to be emitted in multiple translation units.

Before 3.7, the destructors were the key functions for these nodes, but they have been removed.

There have been discussions about this here: http://lists.llvm.org/pipermail/llvm-dev/2015-August/089010.html and here: http://lists.llvm.org/pipermail/llvm-dev/2015-December/092921.html.

Patch by Visoiu Mistrih Francis

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255538 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/IR/Instructions.h b/include/llvm/IR/Instructions.h
index 805a95ea473e3abba033f2da8bf4ce5ad75e3056..d781c7af36d7e3dda810dc5e68034fdbcd55e0de 100644 (file)
--- a/include/llvm/IR/Instructions.h
+++ b/include/llvm/IR/Instructions.h
@@ -839,6 +839,8 @@ class GetElementPtrInst : public Instruction {
   Type *SourceElementType;
   Type *ResultElementType;
 
+  void anchor() override;
+
   GetElementPtrInst(const GetElementPtrInst &GEPI);
   void init(Value *Ptr, ArrayRef<Value *> IdxList, const Twine &NameStr);
 
@@ -1097,6 +1099,8 @@ DEFINE_TRANSPARENT_OPERAND_ACCESSORS(GetElementPtrInst, Value)
 /// must be identical types.
 /// \brief Represent an integer comparison operator.
 class ICmpInst: public CmpInst {
+  void anchor() override;
+
   void AssertOK() {
     assert(getPredicate() >= CmpInst::FIRST_ICMP_PREDICATE &&
            getPredicate() <= CmpInst::LAST_ICMP_PREDICATE &&
@@ -2426,6 +2430,8 @@ DEFINE_TRANSPARENT_OPERAND_ACCESSORS(InsertValueInst, Value)
 // scientist's overactive imagination.
 //
 class PHINode : public Instruction {
+  void anchor() override;
+
   void *operator new(size_t, unsigned) = delete;
   /// ReservedSpace - The number of operands actually allocated.  NumOperands is
   /// the number actually in use.

diff --git a/lib/IR/Instructions.cpp b/lib/IR/Instructions.cpp
index 5863456adfcd5b325f344f603852cd9b1cf06ca1..fb04aa528454fdddab18505d024a76dfd389726b 100644 (file)
--- a/lib/IR/Instructions.cpp
+++ b/lib/IR/Instructions.cpp
@@ -87,6 +87,8 @@ const char *SelectInst::areInvalidOperands(Value *Op0, Value *Op1, Value *Op2) {
 //                               PHINode Class
 //===----------------------------------------------------------------------===//
 
+void PHINode::anchor() {}
+
 PHINode::PHINode(const PHINode &PN)
     : Instruction(PN.getType(), Instruction::PHI, nullptr, PN.getNumOperands()),
       ReservedSpace(PN.getNumOperands()) {
@@ -1503,6 +1505,8 @@ FenceInst::FenceInst(LLVMContext &C, AtomicOrdering Ordering,
 //                       GetElementPtrInst Implementation
 //===----------------------------------------------------------------------===//
 
+void GetElementPtrInst::anchor() {}
+
 void GetElementPtrInst::init(Value *Ptr, ArrayRef<Value *> IdxList,
                              const Twine &Name) {
   assert(getNumOperands() == 1 + IdxList.size() &&
@@ -3389,6 +3393,8 @@ CmpInst::Predicate CmpInst::getInversePredicate(Predicate pred) {
   }
 }
 
+void ICmpInst::anchor() {}
+
 ICmpInst::Predicate ICmpInst::getSignedPredicate(Predicate pred) {
   switch (pred) {
     default: llvm_unreachable("Unknown icmp predicate!");