131 lines · cpp
1//===- llvm/unittest/ADT/PointerIntPairTest.cpp - Unit tests --------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "llvm/ADT/PointerIntPair.h"10#include "gtest/gtest.h"11#include <limits>12using namespace llvm;13 14namespace {15 16TEST(PointerIntPairTest, GetSet) {17 struct S {18 int i;19 };20 S s;21 22 PointerIntPair<S *, 2> Pair(&s, 1U);23 EXPECT_EQ(&s, Pair.getPointer());24 EXPECT_EQ(1U, Pair.getInt());25 26 Pair.setInt(2);27 EXPECT_EQ(&s, Pair.getPointer());28 EXPECT_EQ(2U, Pair.getInt());29 30 Pair.setPointer(nullptr);31 EXPECT_EQ(nullptr, Pair.getPointer());32 EXPECT_EQ(2U, Pair.getInt());33 34 Pair.setPointerAndInt(&s, 3U);35 EXPECT_EQ(&s, Pair.getPointer());36 EXPECT_EQ(3U, Pair.getInt());37 38 // Make sure that we can perform all of our operations on enum classes.39 //40 // The concern is that enum classes are only explicitly convertible to41 // integers. This means that if we assume in PointerIntPair this, a42 // compilation error will result. This group of tests exercises the enum class43 // code to make sure that we do not run into such issues in the future.44 enum class E : unsigned {45 Case1,46 Case2,47 Case3,48 };49 PointerIntPair<S *, 2, E> Pair2(&s, E::Case1);50 EXPECT_EQ(&s, Pair2.getPointer());51 EXPECT_EQ(E::Case1, Pair2.getInt());52 53 Pair2.setInt(E::Case2);54 EXPECT_EQ(&s, Pair2.getPointer());55 EXPECT_EQ(E::Case2, Pair2.getInt());56 57 Pair2.setPointer(nullptr);58 EXPECT_EQ(nullptr, Pair2.getPointer());59 EXPECT_EQ(E::Case2, Pair2.getInt());60 61 Pair2.setPointerAndInt(&s, E::Case3);62 EXPECT_EQ(&s, Pair2.getPointer());63 EXPECT_EQ(E::Case3, Pair2.getInt());64 65 auto [Pointer2, Int2] = Pair2;66 EXPECT_EQ(Pair2.getPointer(), Pointer2);67 EXPECT_EQ(Pair2.getInt(), Int2);68 69 static_assert(std::is_trivially_copyable_v<PointerIntPair<S *, 2, E>>,70 "trivially copyable");71}72 73TEST(PointerIntPairTest, DefaultInitialize) {74 PointerIntPair<float *, 2> Pair;75 EXPECT_EQ(nullptr, Pair.getPointer());76 EXPECT_EQ(0U, Pair.getInt());77}78 79// In real code this would be a word-sized integer limited to 31 bits.80struct Fixnum31 {81 uintptr_t Value;82};83struct FixnumPointerTraits {84 static inline void *getAsVoidPointer(Fixnum31 Num) {85 return reinterpret_cast<void *>(Num.Value << NumLowBitsAvailable);86 }87 static inline Fixnum31 getFromVoidPointer(void *P) {88 // In real code this would assert that the value is in range.89 return {reinterpret_cast<uintptr_t>(P) >> NumLowBitsAvailable};90 }91 static constexpr int NumLowBitsAvailable =92 std::numeric_limits<uintptr_t>::digits - 31;93};94TEST(PointerIntPairTest, ManyUnusedBits) {95 96 PointerIntPair<Fixnum31, 1, bool, FixnumPointerTraits> pair;97 EXPECT_EQ((uintptr_t)0, pair.getPointer().Value);98 EXPECT_FALSE(pair.getInt());99 100 pair.setPointerAndInt({ 0x7FFFFFFF }, true );101 EXPECT_EQ((uintptr_t)0x7FFFFFFF, pair.getPointer().Value);102 EXPECT_TRUE(pair.getInt());103 104 EXPECT_EQ(FixnumPointerTraits::NumLowBitsAvailable - 1,105 (int)PointerLikeTypeTraits<decltype(pair)>::NumLowBitsAvailable);106 107 static_assert(std::is_trivially_copyable_v<108 PointerIntPair<Fixnum31, 1, bool, FixnumPointerTraits>>,109 "trivially copyable");110}111 112TEST(PointerIntPairTest, TypePunning) {113 int I = 0;114 int *IntPtr = &I;115 116 int **IntPtrBegin = &IntPtr;117 int **IntPtrEnd = IntPtrBegin + 1;118 119 PointerIntPair<int *, 1> Pair;120 int **PairAddr = Pair.getAddrOfPointer();121 122 while (IntPtrBegin != IntPtrEnd) {123 *PairAddr = *IntPtrBegin;124 ++PairAddr;125 ++IntPtrBegin;126 }127 EXPECT_EQ(Pair.getPointer(), IntPtr);128}129 130} // end anonymous namespace131