unittests/Analysis/MemoryBuiltinsTest.cpp

   1 //===- MemoryBuiltinsTest.cpp - Tests for utilities in MemoryBuiltins.h ---===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "llvm/Analysis/MemoryBuiltins.h"
  11 #include "llvm/IR/Attributes.h"
  12 #include "llvm/IR/Constants.h"
  13 #include "llvm/IR/Function.h"
  14 #include "llvm/IR/LLVMContext.h"
  15 #include "llvm/IR/Module.h"
  16 #include "gtest/gtest.h"
  17
  18 using namespace llvm;
  19
  20 namespace {
  21 // allocsize should not imply that a function is a traditional allocation
  22 // function (e.g. that can be optimized out/...); it just tells us how many
  23 // bytes exist at the pointer handed back by the function.
  24 TEST(AllocSize, AllocationBuiltinsTest) {
  25   LLVMContext Context;
  26   Module M("", Context);
  27   IntegerType *ArgTy = Type::getInt32Ty(Context);
  28
  29   Function *AllocSizeFn = Function::Create(
  30       FunctionType::get(Type::getInt8PtrTy(Context), {ArgTy}, false),
  31       GlobalValue::ExternalLinkage, "F", &M);
  32
  33   AllocSizeFn->addFnAttr(Attribute::getWithAllocSizeArgs(Context, 1, None));
  34
  35   // 100 is arbitrary.
  36   std::unique_ptr<CallInst> Caller(
  37       CallInst::Create(AllocSizeFn, {ConstantInt::get(ArgTy, 100)}));
  38
  39   const TargetLibraryInfo *TLI = nullptr;
  40   EXPECT_FALSE(isNoAliasFn(Caller.get(), TLI));
  41   EXPECT_FALSE(isMallocLikeFn(Caller.get(), TLI));
  42   EXPECT_FALSE(isCallocLikeFn(Caller.get(), TLI));
  43   EXPECT_FALSE(isAllocLikeFn(Caller.get(), TLI));
  44
  45   // FIXME: We might be able to treat allocsize functions as general allocation
  46   // functions. For the moment, being conservative seems better (and we'd have
  47   // to plumb stuff around `isNoAliasFn`).
  48   EXPECT_FALSE(isAllocationFn(Caller.get(), TLI));
  49 }
  50 }