1 files changed, 50 insertions, 0 deletions
diff --git a/llvm/unittests/Analysis/MemoryBuiltinsTest.cpp b/llvm/unittests/Analysis/MemoryBuiltinsTest.cpp
new file mode 100644
index 00000000000..898ebeece4f
--- /dev/null
+++ b/llvm/unittests/Analysis/MemoryBuiltinsTest.cpp
@@ -0,0 +1,50 @@
+//===- MemoryBuiltinsTest.cpp - Tests for utilities in MemoryBuiltins.h ---===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/MemoryBuiltins.h"
+#include "llvm/IR/Attributes.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+
+namespace {
+// allocsize should not imply that a function is a traditional allocation
+// function (e.g. that can be optimized out/...); it just tells us how many
+// bytes exist at the pointer handed back by the function.
+TEST(AllocSize, AllocationBuiltinsTest) {
+  LLVMContext Context;
+  Module M("", Context);
+  IntegerType *ArgTy = Type::getInt32Ty(Context);
+
+  Function *AllocSizeFn = Function::Create(
+      FunctionType::get(Type::getInt8PtrTy(Context), {ArgTy}, false),
+      GlobalValue::ExternalLinkage, "F", &M);
+
+  AllocSizeFn->addFnAttr(Attribute::getWithAllocSizeArgs(Context, 1, None));
+
+  // 100 is arbitrary.
+  std::unique_ptr<CallInst> Caller(
+      CallInst::Create(AllocSizeFn, {ConstantInt::get(ArgTy, 100)}));
+
+  const TargetLibraryInfo *TLI = nullptr;
+  EXPECT_FALSE(isNoAliasFn(Caller.get(), TLI));
+  EXPECT_FALSE(isMallocLikeFn(Caller.get(), TLI));
+  EXPECT_FALSE(isCallocLikeFn(Caller.get(), TLI));
+  EXPECT_FALSE(isAllocLikeFn(Caller.get(), TLI));
+
+  // FIXME: We might be able to treat allocsize functions as general allocation
+  // functions. For the moment, being conservative seems better (and we'd have
+  // to plumb stuff around `isNoAliasFn`).
+  EXPECT_FALSE(isAllocationFn(Caller.get(), TLI));
+}
+}