unittests/Support/EndianTest.cpp

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