[AbstractCallSite] Handle Indirect Calls Properly

Author: Camsyn

llvm/include/llvm/IR/AbstractCallSite.h

@@ -137,7 +137,7 @@ class AbstractCallSite {
 
   /// Return true if @p U is the use that defines the callee of this ACS.
   bool isCallee(const Use *U) const {
-    if (isDirectCall())
+    if (!isCallbackCall())
       return CB->isCallee(U);
 
     assert(!CI.ParameterEncoding.empty() &&
@@ -154,7 +154,7 @@ class AbstractCallSite {
 
   /// Return the number of parameters of the callee.
   unsigned getNumArgOperands() const {
-    if (isDirectCall())
+    if (!isCallbackCall())
       return CB->arg_size();
     // Subtract 1 for the callee encoding.
     return CI.ParameterEncoding.size() - 1;
@@ -169,7 +169,7 @@ class AbstractCallSite {
   /// Return the operand index of the underlying instruction associated with
   /// the function parameter number @p ArgNo or -1 if there is none.
   int getCallArgOperandNo(unsigned ArgNo) const {
-    if (isDirectCall())
+    if (!isCallbackCall())
       return ArgNo;
     // Add 1 for the callee encoding.
     return CI.ParameterEncoding[ArgNo + 1];
@@ -183,7 +183,7 @@ class AbstractCallSite {
   /// Return the operand of the underlying instruction associated with the
   /// function parameter number @p ArgNo or nullptr if there is none.
   Value *getCallArgOperand(unsigned ArgNo) const {
-    if (isDirectCall())
+    if (!isCallbackCall())
       return CB->getArgOperand(ArgNo);
     // Add 1 for the callee encoding.
     return CI.ParameterEncoding[ArgNo + 1] >= 0
@@ -210,7 +210,7 @@ class AbstractCallSite {
 
   /// Return the pointer to function that is being called.
   Value *getCalledOperand() const {
-    if (isDirectCall())
+    if (!isCallbackCall())
       return CB->getCalledOperand();
     return CB->getArgOperand(getCallArgOperandNoForCallee());
   }

llvm/unittests/IR/AbstractCallSiteTest.cpp

@@ -53,3 +53,56 @@ TEST(AbstractCallSite, CallbackCall) {
   EXPECT_TRUE(ACS.isCallee(CallbackUse));
   EXPECT_EQ(ACS.getCalledFunction(), Callback);
 }
+
+TEST(AbstractCallSite, DirectCall) {
+  LLVMContext C;
+
+  const char *IR = "declare void @bar()\n"
+                   "define void @foo() {\n"
+                   "  call void @bar()\n"
+                   "  ret void\n"
+                   "}\n";
+
+  std::unique_ptr<Module> M = parseIR(C, IR);
+  ASSERT_TRUE(M);
+
+  Function *Callee = M->getFunction("bar");
+  ASSERT_NE(Callee, nullptr);
+
+  const Use *DirectCallUse = Callee->getSingleUndroppableUse();
+  ASSERT_NE(DirectCallUse, nullptr);
+
+  AbstractCallSite ACS(DirectCallUse);
+  EXPECT_TRUE(ACS);
+  EXPECT_TRUE(ACS.isDirectCall());
+  EXPECT_TRUE(ACS.isCallee(DirectCallUse));
+  EXPECT_EQ(ACS.getCalledFunction(), Callee);
+}
+
+TEST(AbstractCallSite, IndirectCall) {
+  LLVMContext C;
+
+  const char *IR = "define void @foo(ptr %0) {\n"
+                   "  call void %0()\n"
+                   "  ret void\n"
+                   "}\n";
+
+  std::unique_ptr<Module> M = parseIR(C, IR);
+  ASSERT_TRUE(M);
+
+  Function *Fun = M->getFunction("foo");
+  ASSERT_NE(Fun, nullptr);
+
+  Argument *ArgAsCallee = Fun->getArg(0);
+  ASSERT_NE(ArgAsCallee, nullptr);
+
+  const Use *IndCallUse = ArgAsCallee->getSingleUndroppableUse();
+  ASSERT_NE(IndCallUse, nullptr);
+
+  AbstractCallSite ACS(IndCallUse);
+  EXPECT_TRUE(ACS);
+  EXPECT_TRUE(ACS.isIndirectCall());
+  EXPECT_TRUE(ACS.isCallee(IndCallUse));
+  EXPECT_EQ(ACS.getCalledFunction(), nullptr);
+  EXPECT_EQ(ACS.getCalledOperand(), ArgAsCallee);
+}