[SandboxIR] Implement NoCFIValue (#109046)

This patch implements sandboxir::NoCFIValue mirroring llvm::NoCFIValue.

Author: vporpo

llvm/include/llvm/SandboxIR/SandboxIR.h

@@ -133,6 +133,7 @@ class GlobalObject;
 class GlobalIFunc;
 class GlobalVariable;
 class GlobalAlias;
+class NoCFIValue;
 class Context;
 class Function;
 class Instruction;
@@ -340,6 +341,7 @@ class Value {
   friend class GlobalIFunc;           // For `Val`.
   friend class GlobalVariable;        // For `Val`.
   friend class GlobalAlias;           // For `Val`.
+  friend class NoCFIValue;            // For `Val`.
 
   /// All values point to the context.
   Context &Ctx;
@@ -1564,6 +1566,43 @@ class GlobalAlias final
   }
 };
 
+class NoCFIValue final : public Constant {
+  NoCFIValue(llvm::NoCFIValue *C, Context &Ctx)
+      : Constant(ClassID::NoCFIValue, C, Ctx) {}
+  friend class Context; // For constructor.
+
+  Use getOperandUseInternal(unsigned OpIdx, bool Verify) const final {
+    return getOperandUseDefault(OpIdx, Verify);
+  }
+
+public:
+  /// Return a NoCFIValue for the specified function.
+  static NoCFIValue *get(GlobalValue *GV);
+
+  GlobalValue *getGlobalValue() const;
+
+  /// NoCFIValue is always a pointer.
+  PointerType *getType() const;
+  /// For isa/dyn_cast.
+  static bool classof(const sandboxir::Value *From) {
+    return From->getSubclassID() == ClassID::NoCFIValue;
+  }
+
+  unsigned getUseOperandNo(const Use &Use) const final {
+    return getUseOperandNoDefault(Use);
+  }
+
+#ifndef NDEBUG
+  void verify() const override {
+    assert(isa<llvm::NoCFIValue>(Val) && "Expected a NoCFIValue!");
+  }
+  void dumpOS(raw_ostream &OS) const override {
+    dumpCommonPrefix(OS);
+    dumpCommonSuffix(OS);
+  }
+#endif
+};
+
 class BlockAddress final : public Constant {
   BlockAddress(llvm::BlockAddress *C, Context &Ctx)
       : Constant(ClassID::BlockAddress, C, Ctx) {}

llvm/include/llvm/SandboxIR/SandboxIRValues.def

@@ -38,6 +38,7 @@ DEF_CONST(GlobalVariable, GlobalVariable)
 DEF_CONST(GlobalIFunc, GlobalIFunc)
 DEF_CONST(GlobalAlias, GlobalAlias)
 DEF_CONST(BlockAddress, BlockAddress)
+DEF_CONST(NoCFIValue, NoCFIValue)
 DEF_CONST(DSOLocalEquivalent, DSOLocalEquivalent)
 DEF_CONST(ConstantTokenNone, ConstantTokenNone)
 

llvm/lib/SandboxIR/SandboxIR.cpp

@@ -2626,6 +2626,20 @@ void GlobalValue::setVisibility(VisibilityTypes V) {
   cast<llvm::GlobalValue>(Val)->setVisibility(V);
 }
 
+NoCFIValue *NoCFIValue::get(GlobalValue *GV) {
+  auto *LLVMC = llvm::NoCFIValue::get(cast<llvm::GlobalValue>(GV->Val));
+  return cast<NoCFIValue>(GV->getContext().getOrCreateConstant(LLVMC));
+}
+
+GlobalValue *NoCFIValue::getGlobalValue() const {
+  auto *LLVMC = cast<llvm::NoCFIValue>(Val)->getGlobalValue();
+  return cast<GlobalValue>(Ctx.getOrCreateConstant(LLVMC));
+}
+
+PointerType *NoCFIValue::getType() const {
+  return cast<PointerType>(Ctx.getType(cast<llvm::NoCFIValue>(Val)->getType()));
+}
+
 BlockAddress *BlockAddress::get(Function *F, BasicBlock *BB) {
   auto *LLVMC = llvm::BlockAddress::get(cast<llvm::Function>(F->Val),
                                         cast<llvm::BasicBlock>(BB->Val));
@@ -2832,6 +2846,10 @@ Value *Context::getOrCreateValueInternal(llvm::Value *LLVMV, llvm::User *U) {
       It->second = std::unique_ptr<GlobalAlias>(
           new GlobalAlias(cast<llvm::GlobalAlias>(C), *this));
       break;
+    case llvm::Value::NoCFIValueVal:
+      It->second = std::unique_ptr<NoCFIValue>(
+          new NoCFIValue(cast<llvm::NoCFIValue>(C), *this));
+      break;
     default:
       It->second = std::unique_ptr<Constant>(new Constant(C, *this));
       break;

llvm/unittests/SandboxIR/SandboxIRTest.cpp

@@ -1117,6 +1117,31 @@ define void @foo() {
             Ctx.getValue(LLVMAlias0->getAliaseeObject()));
 }
 
+TEST_F(SandboxIRTest, NoCFIValue) {
+  parseIR(C, R"IR(
+define void @foo() {
+  call void no_cfi @foo()
+  ret void
+}
+)IR");
+  Function &LLVMF = *M->getFunction("foo");
+  sandboxir::Context Ctx(C);
+
+  auto &F = *Ctx.createFunction(&LLVMF);
+  auto *BB = &*F.begin();
+  auto It = BB->begin();
+  auto *Call = cast<sandboxir::CallInst>(&*It++);
+  // Check classof(), creation.
+  auto *NoCFI = cast<sandboxir::NoCFIValue>(Call->getCalledOperand());
+  // Check get().
+  auto *NewNoCFI = sandboxir::NoCFIValue::get(&F);
+  EXPECT_EQ(NewNoCFI, NoCFI);
+  // Check getGlobalValue().
+  EXPECT_EQ(NoCFI->getGlobalValue(), &F);
+  // Check getType().
+  EXPECT_EQ(NoCFI->getType(), F.getType());
+}
+
 TEST_F(SandboxIRTest, BlockAddress) {
   parseIR(C, R"IR(
 define void @foo(ptr %ptr) {