llvm/unittests/Support/EndianTest.cpp

   1 //===- unittests/Support/EndianTest.cpp - Endian.h 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-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "llvm/Support/Endian.h"
  10 #include "llvm/Support/DataTypes.h"
  11 #include "gtest/gtest.h"
  12 #include <cstdlib>
  13 #include <ctime>
  14 using namespace llvm;
  15 using namespace support;
  16
  17 #undef max
  18
  19 namespace {
  20
  21 TEST(Endian, Read) {
  22   // These are 5 bytes so we can be sure at least one of the reads is unaligned.
  23   unsigned char bigval[] = {0x00, 0x01, 0x02, 0x03, 0x04};
  24   unsigned char littleval[] = {0x00, 0x04, 0x03, 0x02, 0x01};
  25   int32_t BigAsHost = 0x00010203;
  26   EXPECT_EQ(BigAsHost,
  27             (endian::read<int32_t, llvm::endianness::big, unaligned>(bigval)));
  28   int32_t LittleAsHost = 0x02030400;
  29   EXPECT_EQ(
  30       LittleAsHost,
  31       (endian::read<int32_t, llvm::endianness::little, unaligned>(littleval)));
  32
  33   EXPECT_EQ(
  34       (endian::read<int32_t, llvm::endianness::big, unaligned>(bigval + 1)),
  35       (endian::read<int32_t, llvm::endianness::little, unaligned>(littleval +
  36                                                                   1)));
  37 }
  38
  39 TEST(Endian, WriteNext) {
  40   unsigned char bigval[] = {0x00, 0x00}, *p = bigval;
  41   endian::writeNext<int16_t, llvm::endianness::big>(p, short(0xaabb));
  42   EXPECT_EQ(bigval[0], 0xaa);
  43   EXPECT_EQ(bigval[1], 0xbb);
  44   EXPECT_EQ(p, bigval + 2);
  45
  46   char littleval[8] = {}, *q = littleval;
  47   endian::writeNext<uint32_t, llvm::endianness::little>(q, 0x44556677);
  48   EXPECT_EQ(littleval[0], 0x77);
  49   EXPECT_EQ(littleval[1], 0x66);
  50   EXPECT_EQ(littleval[2], 0x55);
  51   EXPECT_EQ(littleval[3], 0x44);
  52   EXPECT_EQ(q, littleval + 4);
  53
  54   endian::writeNext<uint32_t>(q, 0x11223344, llvm::endianness::little);
  55   EXPECT_EQ(littleval[4], 0x44);
  56   EXPECT_EQ(littleval[5], 0x33);
  57   EXPECT_EQ(littleval[6], 0x22);
  58   EXPECT_EQ(littleval[7], 0x11);
  59   EXPECT_EQ(q, littleval + 8);
  60 }
  61
  62 TEST(Endian, ReadBitAligned) {
  63   // Simple test to make sure we properly pull out the 0x0 word.
  64   unsigned char littleval[] = {0x3f, 0x00, 0x00, 0x00, 0xc0, 0xff, 0xff, 0xff};
  65   unsigned char bigval[] = {0x00, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xff, 0xc0};
  66   EXPECT_EQ(
  67       (endian::readAtBitAlignment<int, llvm::endianness::little, unaligned>(
  68           &littleval[0], 6)),
  69       0x0);
  70   EXPECT_EQ((endian::readAtBitAlignment<int, llvm::endianness::big, unaligned>(
  71                 &bigval[0], 6)),
  72             0x0);
  73   // Test to make sure that signed right shift of 0xf0000000 is masked
  74   // properly.
  75   unsigned char littleval2[] = {0x00, 0x00, 0x00, 0xf0, 0x00, 0x00, 0x00, 0x00};
  76   unsigned char bigval2[] = {0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
  77   EXPECT_EQ(
  78       (endian::readAtBitAlignment<int, llvm::endianness::little, unaligned>(
  79           &littleval2[0], 4)),
  80       0x0f000000);
  81   EXPECT_EQ((endian::readAtBitAlignment<int, llvm::endianness::big, unaligned>(
  82                 &bigval2[0], 4)),
  83             0x0f000000);
  84   // Test to make sure left shift of start bit doesn't overflow.
  85   EXPECT_EQ(
  86       (endian::readAtBitAlignment<int, llvm::endianness::little, unaligned>(
  87           &littleval2[0], 1)),
  88       0x78000000);
  89   EXPECT_EQ((endian::readAtBitAlignment<int, llvm::endianness::big, unaligned>(
  90                 &bigval2[0], 1)),
  91             0x78000000);
  92   // Test to make sure 64-bit int doesn't overflow.
  93   unsigned char littleval3[] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf0,
  94                                 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
  95   unsigned char bigval3[] = {0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  96                              0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
  97   EXPECT_EQ(
  98       (endian::readAtBitAlignment<int64_t, llvm::endianness::little, unaligned>(
  99           &littleval3[0], 4)),
 100       0x0f00000000000000);
 101   EXPECT_EQ(
 102       (endian::readAtBitAlignment<int64_t, llvm::endianness::big, unaligned>(
 103           &bigval3[0], 4)),
 104       0x0f00000000000000);
 105 }
 106
 107 TEST(Endian, WriteBitAligned) {
 108   // This test ensures that signed right shift of 0xffffaa is masked
 109   // properly.
 110   unsigned char bigval[8] = {0x00};
 111   endian::writeAtBitAlignment<int32_t, llvm::endianness::big, unaligned>(
 112       bigval, (int)0xffffaaaa, 4);
 113   EXPECT_EQ(bigval[0], 0xff);
 114   EXPECT_EQ(bigval[1], 0xfa);
 115   EXPECT_EQ(bigval[2], 0xaa);
 116   EXPECT_EQ(bigval[3], 0xa0);
 117   EXPECT_EQ(bigval[4], 0x00);
 118   EXPECT_EQ(bigval[5], 0x00);
 119   EXPECT_EQ(bigval[6], 0x00);
 120   EXPECT_EQ(bigval[7], 0x0f);
 121
 122   unsigned char littleval[8] = {0x00};
 123   endian::writeAtBitAlignment<int32_t, llvm::endianness::little, unaligned>(
 124       littleval, (int)0xffffaaaa, 4);
 125   EXPECT_EQ(littleval[0], 0xa0);
 126   EXPECT_EQ(littleval[1], 0xaa);
 127   EXPECT_EQ(littleval[2], 0xfa);
 128   EXPECT_EQ(littleval[3], 0xff);
 129   EXPECT_EQ(littleval[4], 0x0f);
 130   EXPECT_EQ(littleval[5], 0x00);
 131   EXPECT_EQ(littleval[6], 0x00);
 132   EXPECT_EQ(littleval[7], 0x00);
 133
 134   // This test makes sure 1<<31 doesn't overflow.
 135   // Test to make sure left shift of start bit doesn't overflow.
 136   unsigned char bigval2[8] = {0x00};
 137   endian::writeAtBitAlignment<int32_t, llvm::endianness::big, unaligned>(
 138       bigval2, (int)0xffffffff, 1);
 139   EXPECT_EQ(bigval2[0], 0xff);
 140   EXPECT_EQ(bigval2[1], 0xff);
 141   EXPECT_EQ(bigval2[2], 0xff);
 142   EXPECT_EQ(bigval2[3], 0xfe);
 143   EXPECT_EQ(bigval2[4], 0x00);
 144   EXPECT_EQ(bigval2[5], 0x00);
 145   EXPECT_EQ(bigval2[6], 0x00);
 146   EXPECT_EQ(bigval2[7], 0x01);
 147
 148   unsigned char littleval2[8] = {0x00};
 149   endian::writeAtBitAlignment<int32_t, llvm::endianness::little, unaligned>(
 150       littleval2, (int)0xffffffff, 1);
 151   EXPECT_EQ(littleval2[0], 0xfe);
 152   EXPECT_EQ(littleval2[1], 0xff);
 153   EXPECT_EQ(littleval2[2], 0xff);
 154   EXPECT_EQ(littleval2[3], 0xff);
 155   EXPECT_EQ(littleval2[4], 0x01);
 156   EXPECT_EQ(littleval2[5], 0x00);
 157   EXPECT_EQ(littleval2[6], 0x00);
 158   EXPECT_EQ(littleval2[7], 0x00);
 159
 160   // Test to make sure 64-bit int doesn't overflow.
 161   unsigned char bigval64[16] = {0x00};
 162   endian::writeAtBitAlignment<int64_t, llvm::endianness::big, unaligned>(
 163       bigval64, (int64_t)0xffffffffffffffff, 1);
 164   EXPECT_EQ(bigval64[0], 0xff);
 165   EXPECT_EQ(bigval64[1], 0xff);
 166   EXPECT_EQ(bigval64[2], 0xff);
 167   EXPECT_EQ(bigval64[3], 0xff);
 168   EXPECT_EQ(bigval64[4], 0xff);
 169   EXPECT_EQ(bigval64[5], 0xff);
 170   EXPECT_EQ(bigval64[6], 0xff);
 171   EXPECT_EQ(bigval64[7], 0xfe);
 172   EXPECT_EQ(bigval64[8], 0x00);
 173   EXPECT_EQ(bigval64[9], 0x00);
 174   EXPECT_EQ(bigval64[10], 0x00);
 175   EXPECT_EQ(bigval64[11], 0x00);
 176   EXPECT_EQ(bigval64[12], 0x00);
 177   EXPECT_EQ(bigval64[13], 0x00);
 178   EXPECT_EQ(bigval64[14], 0x00);
 179   EXPECT_EQ(bigval64[15], 0x01);
 180
 181   unsigned char littleval64[16] = {0x00};
 182   endian::writeAtBitAlignment<int64_t, llvm::endianness::little, unaligned>(
 183       littleval64, (int64_t)0xffffffffffffffff, 1);
 184   EXPECT_EQ(littleval64[0], 0xfe);
 185   EXPECT_EQ(littleval64[1], 0xff);
 186   EXPECT_EQ(littleval64[2], 0xff);
 187   EXPECT_EQ(littleval64[3], 0xff);
 188   EXPECT_EQ(littleval64[4], 0xff);
 189   EXPECT_EQ(littleval64[5], 0xff);
 190   EXPECT_EQ(littleval64[6], 0xff);
 191   EXPECT_EQ(littleval64[7], 0xff);
 192   EXPECT_EQ(littleval64[8], 0x01);
 193   EXPECT_EQ(littleval64[9], 0x00);
 194   EXPECT_EQ(littleval64[10], 0x00);
 195   EXPECT_EQ(littleval64[11], 0x00);
 196   EXPECT_EQ(littleval64[12], 0x00);
 197   EXPECT_EQ(littleval64[13], 0x00);
 198   EXPECT_EQ(littleval64[14], 0x00);
 199   EXPECT_EQ(littleval64[15], 0x00);
 200 }
 201
 202 TEST(Endian, Write) {
 203   unsigned char data[5];
 204   endian::write<int32_t, llvm::endianness::big, unaligned>(data, -1362446643);
 205   EXPECT_EQ(data[0], 0xAE);
 206   EXPECT_EQ(data[1], 0xCA);
 207   EXPECT_EQ(data[2], 0xB6);
 208   EXPECT_EQ(data[3], 0xCD);
 209   endian::write<int32_t, llvm::endianness::big, unaligned>(data + 1,
 210                                                            -1362446643);
 211   EXPECT_EQ(data[1], 0xAE);
 212   EXPECT_EQ(data[2], 0xCA);
 213   EXPECT_EQ(data[3], 0xB6);
 214   EXPECT_EQ(data[4], 0xCD);
 215
 216   endian::write<int32_t, llvm::endianness::little, unaligned>(data,
 217                                                               -1362446643);
 218   EXPECT_EQ(data[0], 0xCD);
 219   EXPECT_EQ(data[1], 0xB6);
 220   EXPECT_EQ(data[2], 0xCA);
 221   EXPECT_EQ(data[3], 0xAE);
 222   endian::write<int32_t, llvm::endianness::little, unaligned>(data + 1,
 223                                                               -1362446643);
 224   EXPECT_EQ(data[1], 0xCD);
 225   EXPECT_EQ(data[2], 0xB6);
 226   EXPECT_EQ(data[3], 0xCA);
 227   EXPECT_EQ(data[4], 0xAE);
 228 }
 229
 230 TEST(Endian, PackedEndianSpecificIntegral) {
 231   // These are 5 bytes so we can be sure at least one of the reads is unaligned.
 232   unsigned char big[] = {0x00, 0x01, 0x02, 0x03, 0x04};
 233   unsigned char little[] = {0x00, 0x04, 0x03, 0x02, 0x01};
 234   big32_t    *big_val    =
 235     reinterpret_cast<big32_t *>(big + 1);
 236   little32_t *little_val =
 237     reinterpret_cast<little32_t *>(little + 1);
 238
 239   EXPECT_EQ(*big_val, *little_val);
 240 }
 241
 242 TEST(Endian, PacketEndianSpecificIntegralAsEnum) {
 243   enum class Test : uint16_t { ONETWO = 0x0102, TWOONE = 0x0201 };
 244   unsigned char bytes[] = {0x01, 0x02};
 245   using LittleTest = little_t<Test>;
 246   using BigTest = big_t<Test>;
 247   EXPECT_EQ(Test::TWOONE, *reinterpret_cast<LittleTest *>(bytes));
 248   EXPECT_EQ(Test::ONETWO, *reinterpret_cast<BigTest *>(bytes));
 249 }
 250
 251 } // end anon namespace