base/numerics/safe_numerics_unittest.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #if defined(COMPILER_MSVC) && defined(ARCH_CPU_32_BITS)
   6 #include <mmintrin.h>
   7 #endif
   8 #include <stdint.h>
   9
  10 #include <limits>
  11
  12 #include "base/compiler_specific.h"
  13 #include "base/numerics/safe_conversions.h"
  14 #include "base/numerics/safe_math.h"
  15 #include "base/template_util.h"
  16 #include "testing/gtest/include/gtest/gtest.h"
  17
  18 using std::numeric_limits;
  19 using base::CheckedNumeric;
  20 using base::checked_cast;
  21 using base::saturated_cast;
  22 using base::internal::MaxExponent;
  23 using base::internal::RANGE_VALID;
  24 using base::internal::RANGE_INVALID;
  25 using base::internal::RANGE_OVERFLOW;
  26 using base::internal::RANGE_UNDERFLOW;
  27 using base::enable_if;
  28
  29 // MSVS 2013 ia32 may not reset the FPU between calculations, and the test
  30 // framework masks the exceptions. So we just force a manual reset after NaN.
  31 inline void ResetFloatingPointUnit() {
  32 #if defined(COMPILER_MSVC) && defined(ARCH_CPU_32_BITS)
  33   _mm_empty();
  34 #endif
  35 }
  36
  37 // Helper macros to wrap displaying the conversion types and line numbers.
  38 #define TEST_EXPECTED_VALIDITY(expected, actual)                           \
  39   EXPECT_EQ(expected, CheckedNumeric<Dst>(actual).validity())              \
  40       << "Result test: Value " << +(actual).ValueUnsafe() << " as " << dst \
  41       << " on line " << line;
  42
  43 #define TEST_EXPECTED_VALUE(expected, actual)                                \
  44   EXPECT_EQ(static_cast<Dst>(expected),                                      \
  45             CheckedNumeric<Dst>(actual).ValueUnsafe())                       \
  46       << "Result test: Value " << +((actual).ValueUnsafe()) << " as " << dst \
  47       << " on line " << line;
  48
  49 // Signed integer arithmetic.
  50 template <typename Dst>
  51 static void TestSpecializedArithmetic(
  52     const char* dst,
  53     int line,
  54     typename enable_if<
  55         numeric_limits<Dst>::is_integer&& numeric_limits<Dst>::is_signed,
  56         int>::type = 0) {
  57   typedef numeric_limits<Dst> DstLimits;
  58   TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW,
  59                          -CheckedNumeric<Dst>(DstLimits::min()));
  60   TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW,
  61                          CheckedNumeric<Dst>(DstLimits::min()).Abs());
  62   TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(-1).Abs());
  63
  64   TEST_EXPECTED_VALIDITY(RANGE_VALID,
  65                          CheckedNumeric<Dst>(DstLimits::max()) + -1);
  66   TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW,
  67                          CheckedNumeric<Dst>(DstLimits::min()) + -1);
  68   TEST_EXPECTED_VALIDITY(
  69       RANGE_UNDERFLOW,
  70       CheckedNumeric<Dst>(-DstLimits::max()) + -DstLimits::max());
  71
  72   TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW,
  73                          CheckedNumeric<Dst>(DstLimits::min()) - 1);
  74   TEST_EXPECTED_VALIDITY(RANGE_VALID,
  75                          CheckedNumeric<Dst>(DstLimits::min()) - -1);
  76   TEST_EXPECTED_VALIDITY(
  77       RANGE_OVERFLOW,
  78       CheckedNumeric<Dst>(DstLimits::max()) - -DstLimits::max());
  79   TEST_EXPECTED_VALIDITY(
  80       RANGE_UNDERFLOW,
  81       CheckedNumeric<Dst>(-DstLimits::max()) - DstLimits::max());
  82
  83   TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW,
  84                          CheckedNumeric<Dst>(DstLimits::min()) * 2);
  85
  86   TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW,
  87                          CheckedNumeric<Dst>(DstLimits::min()) / -1);
  88   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(-1) / 2);
  89
  90   // Modulus is legal only for integers.
  91   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>() % 1);
  92   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % 1);
  93   TEST_EXPECTED_VALUE(-1, CheckedNumeric<Dst>(-1) % 2);
  94   TEST_EXPECTED_VALIDITY(RANGE_INVALID, CheckedNumeric<Dst>(-1) % -2);
  95   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(DstLimits::min()) % 2);
  96   TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(DstLimits::max()) % 2);
  97   // Test all the different modulus combinations.
  98   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % CheckedNumeric<Dst>(1));
  99   TEST_EXPECTED_VALUE(0, 1 % CheckedNumeric<Dst>(1));
 100   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % 1);
 101   CheckedNumeric<Dst> checked_dst = 1;
 102   TEST_EXPECTED_VALUE(0, checked_dst %= 1);
 103 }
 104
 105 // Unsigned integer arithmetic.
 106 template <typename Dst>
 107 static void TestSpecializedArithmetic(
 108     const char* dst,
 109     int line,
 110     typename enable_if<
 111         numeric_limits<Dst>::is_integer && !numeric_limits<Dst>::is_signed,
 112         int>::type = 0) {
 113   typedef numeric_limits<Dst> DstLimits;
 114   TEST_EXPECTED_VALIDITY(RANGE_VALID, -CheckedNumeric<Dst>(DstLimits::min()));
 115   TEST_EXPECTED_VALIDITY(RANGE_VALID,
 116                          CheckedNumeric<Dst>(DstLimits::min()).Abs());
 117   TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW,
 118                          CheckedNumeric<Dst>(DstLimits::min()) + -1);
 119   TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW,
 120                          CheckedNumeric<Dst>(DstLimits::min()) - 1);
 121   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(DstLimits::min()) * 2);
 122   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) / 2);
 123
 124   // Modulus is legal only for integers.
 125   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>() % 1);
 126   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % 1);
 127   TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) % 2);
 128   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(DstLimits::min()) % 2);
 129   TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(DstLimits::max()) % 2);
 130   // Test all the different modulus combinations.
 131   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % CheckedNumeric<Dst>(1));
 132   TEST_EXPECTED_VALUE(0, 1 % CheckedNumeric<Dst>(1));
 133   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % 1);
 134   CheckedNumeric<Dst> checked_dst = 1;
 135   TEST_EXPECTED_VALUE(0, checked_dst %= 1);
 136 }
 137
 138 // Floating point arithmetic.
 139 template <typename Dst>
 140 void TestSpecializedArithmetic(
 141     const char* dst,
 142     int line,
 143     typename enable_if<numeric_limits<Dst>::is_iec559, int>::type = 0) {
 144   typedef numeric_limits<Dst> DstLimits;
 145   TEST_EXPECTED_VALIDITY(RANGE_VALID, -CheckedNumeric<Dst>(DstLimits::min()));
 146
 147   TEST_EXPECTED_VALIDITY(RANGE_VALID,
 148                          CheckedNumeric<Dst>(DstLimits::min()).Abs());
 149   TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(-1).Abs());
 150
 151   TEST_EXPECTED_VALIDITY(RANGE_VALID,
 152                          CheckedNumeric<Dst>(DstLimits::min()) + -1);
 153   TEST_EXPECTED_VALIDITY(RANGE_VALID,
 154                          CheckedNumeric<Dst>(DstLimits::max()) + 1);
 155   TEST_EXPECTED_VALIDITY(
 156       RANGE_UNDERFLOW,
 157       CheckedNumeric<Dst>(-DstLimits::max()) + -DstLimits::max());
 158
 159   TEST_EXPECTED_VALIDITY(
 160       RANGE_OVERFLOW,
 161       CheckedNumeric<Dst>(DstLimits::max()) - -DstLimits::max());
 162   TEST_EXPECTED_VALIDITY(
 163       RANGE_UNDERFLOW,
 164       CheckedNumeric<Dst>(-DstLimits::max()) - DstLimits::max());
 165
 166   TEST_EXPECTED_VALIDITY(RANGE_VALID,
 167                          CheckedNumeric<Dst>(DstLimits::min()) * 2);
 168
 169   TEST_EXPECTED_VALUE(-0.5, CheckedNumeric<Dst>(-1.0) / 2);
 170   EXPECT_EQ(static_cast<Dst>(1.0), CheckedNumeric<Dst>(1.0).ValueFloating());
 171 }
 172
 173 // Generic arithmetic tests.
 174 template <typename Dst>
 175 static void TestArithmetic(const char* dst, int line) {
 176   typedef numeric_limits<Dst> DstLimits;
 177
 178   EXPECT_EQ(true, CheckedNumeric<Dst>().IsValid());
 179   EXPECT_EQ(false,
 180             CheckedNumeric<Dst>(CheckedNumeric<Dst>(DstLimits::max()) *
 181                                 DstLimits::max()).IsValid());
 182   EXPECT_EQ(static_cast<Dst>(0), CheckedNumeric<Dst>().ValueOrDie());
 183   EXPECT_EQ(static_cast<Dst>(0), CheckedNumeric<Dst>().ValueOrDefault(1));
 184   EXPECT_EQ(static_cast<Dst>(1),
 185             CheckedNumeric<Dst>(CheckedNumeric<Dst>(DstLimits::max()) *
 186                                 DstLimits::max()).ValueOrDefault(1));
 187
 188   // Test the operator combinations.
 189   TEST_EXPECTED_VALUE(2, CheckedNumeric<Dst>(1) + CheckedNumeric<Dst>(1));
 190   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) - CheckedNumeric<Dst>(1));
 191   TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) * CheckedNumeric<Dst>(1));
 192   TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) / CheckedNumeric<Dst>(1));
 193   TEST_EXPECTED_VALUE(2, 1 + CheckedNumeric<Dst>(1));
 194   TEST_EXPECTED_VALUE(0, 1 - CheckedNumeric<Dst>(1));
 195   TEST_EXPECTED_VALUE(1, 1 * CheckedNumeric<Dst>(1));
 196   TEST_EXPECTED_VALUE(1, 1 / CheckedNumeric<Dst>(1));
 197   TEST_EXPECTED_VALUE(2, CheckedNumeric<Dst>(1) + 1);
 198   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) - 1);
 199   TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) * 1);
 200   TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) / 1);
 201   CheckedNumeric<Dst> checked_dst = 1;
 202   TEST_EXPECTED_VALUE(2, checked_dst += 1);
 203   checked_dst = 1;
 204   TEST_EXPECTED_VALUE(0, checked_dst -= 1);
 205   checked_dst = 1;
 206   TEST_EXPECTED_VALUE(1, checked_dst *= 1);
 207   checked_dst = 1;
 208   TEST_EXPECTED_VALUE(1, checked_dst /= 1);
 209
 210   // Generic negation.
 211   TEST_EXPECTED_VALUE(0, -CheckedNumeric<Dst>());
 212   TEST_EXPECTED_VALUE(-1, -CheckedNumeric<Dst>(1));
 213   TEST_EXPECTED_VALUE(1, -CheckedNumeric<Dst>(-1));
 214   TEST_EXPECTED_VALUE(static_cast<Dst>(DstLimits::max() * -1),
 215                       -CheckedNumeric<Dst>(DstLimits::max()));
 216
 217   // Generic absolute value.
 218   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>().Abs());
 219   TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1).Abs());
 220   TEST_EXPECTED_VALUE(DstLimits::max(),
 221                       CheckedNumeric<Dst>(DstLimits::max()).Abs());
 222
 223   // Generic addition.
 224   TEST_EXPECTED_VALUE(1, (CheckedNumeric<Dst>() + 1));
 225   TEST_EXPECTED_VALUE(2, (CheckedNumeric<Dst>(1) + 1));
 226   TEST_EXPECTED_VALUE(0, (CheckedNumeric<Dst>(-1) + 1));
 227   TEST_EXPECTED_VALIDITY(RANGE_VALID,
 228                          CheckedNumeric<Dst>(DstLimits::min()) + 1);
 229   TEST_EXPECTED_VALIDITY(
 230       RANGE_OVERFLOW, CheckedNumeric<Dst>(DstLimits::max()) + DstLimits::max());
 231
 232   // Generic subtraction.
 233   TEST_EXPECTED_VALUE(-1, (CheckedNumeric<Dst>() - 1));
 234   TEST_EXPECTED_VALUE(0, (CheckedNumeric<Dst>(1) - 1));
 235   TEST_EXPECTED_VALUE(-2, (CheckedNumeric<Dst>(-1) - 1));
 236   TEST_EXPECTED_VALIDITY(RANGE_VALID,
 237                          CheckedNumeric<Dst>(DstLimits::max()) - 1);
 238
 239   // Generic multiplication.
 240   TEST_EXPECTED_VALUE(0, (CheckedNumeric<Dst>() * 1));
 241   TEST_EXPECTED_VALUE(1, (CheckedNumeric<Dst>(1) * 1));
 242   TEST_EXPECTED_VALUE(-2, (CheckedNumeric<Dst>(-1) * 2));
 243   TEST_EXPECTED_VALIDITY(
 244       RANGE_OVERFLOW, CheckedNumeric<Dst>(DstLimits::max()) * DstLimits::max());
 245
 246   // Generic division.
 247   TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>() / 1);
 248   TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) / 1);
 249   TEST_EXPECTED_VALUE(DstLimits::min() / 2,
 250                       CheckedNumeric<Dst>(DstLimits::min()) / 2);
 251   TEST_EXPECTED_VALUE(DstLimits::max() / 2,
 252                       CheckedNumeric<Dst>(DstLimits::max()) / 2);
 253
 254   TestSpecializedArithmetic<Dst>(dst, line);
 255 }
 256
 257 // Helper macro to wrap displaying the conversion types and line numbers.
 258 #define TEST_ARITHMETIC(Dst) TestArithmetic<Dst>(#Dst, __LINE__)
 259
 260 TEST(SafeNumerics, SignedIntegerMath) {
 261   TEST_ARITHMETIC(int8_t);
 262   TEST_ARITHMETIC(int);
 263   TEST_ARITHMETIC(intptr_t);
 264   TEST_ARITHMETIC(intmax_t);
 265 }
 266
 267 TEST(SafeNumerics, UnsignedIntegerMath) {
 268   TEST_ARITHMETIC(uint8_t);
 269   TEST_ARITHMETIC(unsigned int);
 270   TEST_ARITHMETIC(uintptr_t);
 271   TEST_ARITHMETIC(uintmax_t);
 272 }
 273
 274 TEST(SafeNumerics, FloatingPointMath) {
 275   TEST_ARITHMETIC(float);
 276   TEST_ARITHMETIC(double);
 277 }
 278
 279 // Enumerates the five different conversions types we need to test.
 280 enum NumericConversionType {
 281   SIGN_PRESERVING_VALUE_PRESERVING,
 282   SIGN_PRESERVING_NARROW,
 283   SIGN_TO_UNSIGN_WIDEN_OR_EQUAL,
 284   SIGN_TO_UNSIGN_NARROW,
 285   UNSIGN_TO_SIGN_NARROW_OR_EQUAL,
 286 };
 287
 288 // Template covering the different conversion tests.
 289 template <typename Dst, typename Src, NumericConversionType conversion>
 290 struct TestNumericConversion {};
 291
 292 // EXPECT_EQ wrappers providing specific detail on test failures.
 293 #define TEST_EXPECTED_RANGE(expected, actual)                                  \
 294   EXPECT_EQ(expected, base::internal::DstRangeRelationToSrcRange<Dst>(actual)) \
 295       << "Conversion test: " << src << " value " << actual << " to " << dst    \
 296       << " on line " << line;
 297
 298 template <typename Dst, typename Src>
 299 struct TestNumericConversion<Dst, Src, SIGN_PRESERVING_VALUE_PRESERVING> {
 300   static void Test(const char *dst, const char *src, int line) {
 301     typedef numeric_limits<Src> SrcLimits;
 302     typedef numeric_limits<Dst> DstLimits;
 303                    // Integral to floating.
 304     COMPILE_ASSERT((DstLimits::is_iec559 && SrcLimits::is_integer) ||
 305                    // Not floating to integral and...
 306                    (!(DstLimits::is_integer && SrcLimits::is_iec559) &&
 307                     // Same sign, same numeric, source is narrower or same.
 308                     ((SrcLimits::is_signed == DstLimits::is_signed &&
 309                      sizeof(Dst) >= sizeof(Src)) ||
 310                     // Or signed destination and source is smaller
 311                      (DstLimits::is_signed && sizeof(Dst) > sizeof(Src)))),
 312                    comparison_must_be_sign_preserving_and_value_preserving);
 313
 314     const CheckedNumeric<Dst> checked_dst = SrcLimits::max();
 315     ;
 316     TEST_EXPECTED_VALIDITY(RANGE_VALID, checked_dst);
 317     if (MaxExponent<Dst>::value > MaxExponent<Src>::value) {
 318       if (MaxExponent<Dst>::value >= MaxExponent<Src>::value * 2 - 1) {
 319         // At least twice larger type.
 320         TEST_EXPECTED_VALIDITY(RANGE_VALID, SrcLimits::max() * checked_dst);
 321
 322       } else {  // Larger, but not at least twice as large.
 323         TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW, SrcLimits::max() * checked_dst);
 324         TEST_EXPECTED_VALIDITY(RANGE_VALID, checked_dst + 1);
 325       }
 326     } else {  // Same width type.
 327       TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW, checked_dst + 1);
 328     }
 329
 330     TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::max());
 331     TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(1));
 332     if (SrcLimits::is_iec559) {
 333       TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::max() * static_cast<Src>(-1));
 334       TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::infinity());
 335       TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::infinity() * -1);
 336       TEST_EXPECTED_RANGE(RANGE_INVALID, SrcLimits::quiet_NaN());
 337       ResetFloatingPointUnit();
 338     } else if (numeric_limits<Src>::is_signed) {
 339       TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(-1));
 340       TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::min());
 341     }
 342   }
 343 };
 344
 345 template <typename Dst, typename Src>
 346 struct TestNumericConversion<Dst, Src, SIGN_PRESERVING_NARROW> {
 347   static void Test(const char *dst, const char *src, int line) {
 348     typedef numeric_limits<Src> SrcLimits;
 349     typedef numeric_limits<Dst> DstLimits;
 350     COMPILE_ASSERT(SrcLimits::is_signed == DstLimits::is_signed,
 351                    destination_and_source_sign_must_be_the_same);
 352     COMPILE_ASSERT(sizeof(Dst) < sizeof(Src) ||
 353                    (DstLimits::is_integer && SrcLimits::is_iec559),
 354                    destination_must_be_narrower_than_source);
 355
 356     const CheckedNumeric<Dst> checked_dst;
 357     TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW, checked_dst + SrcLimits::max());
 358     TEST_EXPECTED_VALUE(1, checked_dst + static_cast<Src>(1));
 359     TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW, checked_dst - SrcLimits::max());
 360
 361     TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::max());
 362     TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(1));
 363     if (SrcLimits::is_iec559) {
 364       TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::max() * -1);
 365       TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(-1));
 366       TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::infinity());
 367       TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::infinity() * -1);
 368       TEST_EXPECTED_RANGE(RANGE_INVALID, SrcLimits::quiet_NaN());
 369       ResetFloatingPointUnit();
 370     } else if (SrcLimits::is_signed) {
 371       TEST_EXPECTED_VALUE(-1, checked_dst - static_cast<Src>(1));
 372       TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::min());
 373       TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(-1));
 374     } else {
 375       TEST_EXPECTED_VALIDITY(RANGE_INVALID, checked_dst - static_cast<Src>(1));
 376       TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::min());
 377     }
 378   }
 379 };
 380
 381 template <typename Dst, typename Src>
 382 struct TestNumericConversion<Dst, Src, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL> {
 383   static void Test(const char *dst, const char *src, int line) {
 384     typedef numeric_limits<Src> SrcLimits;
 385     typedef numeric_limits<Dst> DstLimits;
 386     COMPILE_ASSERT(sizeof(Dst) >= sizeof(Src),
 387                    destination_must_be_equal_or_wider_than_source);
 388     COMPILE_ASSERT(SrcLimits::is_signed, source_must_be_signed);
 389     COMPILE_ASSERT(!DstLimits::is_signed, destination_must_be_unsigned);
 390
 391     const CheckedNumeric<Dst> checked_dst;
 392     TEST_EXPECTED_VALUE(SrcLimits::max(), checked_dst + SrcLimits::max());
 393     TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW, checked_dst + static_cast<Src>(-1));
 394     TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW, checked_dst + -SrcLimits::max());
 395
 396     TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::min());
 397     TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::max());
 398     TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(1));
 399     TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, static_cast<Src>(-1));
 400   }
 401 };
 402
 403 template <typename Dst, typename Src>
 404 struct TestNumericConversion<Dst, Src, SIGN_TO_UNSIGN_NARROW> {
 405   static void Test(const char *dst, const char *src, int line) {
 406     typedef numeric_limits<Src> SrcLimits;
 407     typedef numeric_limits<Dst> DstLimits;
 408     COMPILE_ASSERT((DstLimits::is_integer && SrcLimits::is_iec559) ||
 409                    (sizeof(Dst) < sizeof(Src)),
 410       destination_must_be_narrower_than_source);
 411     COMPILE_ASSERT(SrcLimits::is_signed, source_must_be_signed);
 412     COMPILE_ASSERT(!DstLimits::is_signed, destination_must_be_unsigned);
 413
 414     const CheckedNumeric<Dst> checked_dst;
 415     TEST_EXPECTED_VALUE(1, checked_dst + static_cast<Src>(1));
 416     TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW, checked_dst + SrcLimits::max());
 417     TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW, checked_dst + static_cast<Src>(-1));
 418     TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW, checked_dst + -SrcLimits::max());
 419
 420     TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::max());
 421     TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(1));
 422     TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, static_cast<Src>(-1));
 423     if (SrcLimits::is_iec559) {
 424       TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::max() * -1);
 425       TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::infinity());
 426       TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::infinity() * -1);
 427       TEST_EXPECTED_RANGE(RANGE_INVALID, SrcLimits::quiet_NaN());
 428       ResetFloatingPointUnit();
 429     } else {
 430       TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::min());
 431     }
 432   }
 433 };
 434
 435 template <typename Dst, typename Src>
 436 struct TestNumericConversion<Dst, Src, UNSIGN_TO_SIGN_NARROW_OR_EQUAL> {
 437   static void Test(const char *dst, const char *src, int line) {
 438     typedef numeric_limits<Src> SrcLimits;
 439     typedef numeric_limits<Dst> DstLimits;
 440     COMPILE_ASSERT(sizeof(Dst) <= sizeof(Src),
 441                    destination_must_be_narrower_or_equal_to_source);
 442     COMPILE_ASSERT(!SrcLimits::is_signed, source_must_be_unsigned);
 443     COMPILE_ASSERT(DstLimits::is_signed, destination_must_be_signed);
 444
 445     const CheckedNumeric<Dst> checked_dst;
 446     TEST_EXPECTED_VALUE(1, checked_dst + static_cast<Src>(1));
 447     TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW, checked_dst + SrcLimits::max());
 448     TEST_EXPECTED_VALUE(SrcLimits::min(), checked_dst + SrcLimits::min());
 449
 450     TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::min());
 451     TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::max());
 452     TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(1));
 453   }
 454 };
 455
 456 // Helper macro to wrap displaying the conversion types and line numbers
 457 #define TEST_NUMERIC_CONVERSION(d, s, t) \
 458   TestNumericConversion<d, s, t>::Test(#d, #s, __LINE__)
 459
 460 TEST(SafeNumerics, IntMinOperations) {
 461   TEST_NUMERIC_CONVERSION(int8_t, int8_t, SIGN_PRESERVING_VALUE_PRESERVING);
 462   TEST_NUMERIC_CONVERSION(uint8_t, uint8_t, SIGN_PRESERVING_VALUE_PRESERVING);
 463
 464   TEST_NUMERIC_CONVERSION(int8_t, int, SIGN_PRESERVING_NARROW);
 465   TEST_NUMERIC_CONVERSION(uint8_t, unsigned int, SIGN_PRESERVING_NARROW);
 466   TEST_NUMERIC_CONVERSION(int8_t, float, SIGN_PRESERVING_NARROW);
 467
 468   TEST_NUMERIC_CONVERSION(uint8_t, int8_t, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
 469
 470   TEST_NUMERIC_CONVERSION(uint8_t, int, SIGN_TO_UNSIGN_NARROW);
 471   TEST_NUMERIC_CONVERSION(uint8_t, intmax_t, SIGN_TO_UNSIGN_NARROW);
 472   TEST_NUMERIC_CONVERSION(uint8_t, float, SIGN_TO_UNSIGN_NARROW);
 473
 474   TEST_NUMERIC_CONVERSION(int8_t, unsigned int, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
 475   TEST_NUMERIC_CONVERSION(int8_t, uintmax_t, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
 476 }
 477
 478 TEST(SafeNumerics, IntOperations) {
 479   TEST_NUMERIC_CONVERSION(int, int, SIGN_PRESERVING_VALUE_PRESERVING);
 480   TEST_NUMERIC_CONVERSION(unsigned int, unsigned int,
 481                           SIGN_PRESERVING_VALUE_PRESERVING);
 482   TEST_NUMERIC_CONVERSION(int, int8_t, SIGN_PRESERVING_VALUE_PRESERVING);
 483   TEST_NUMERIC_CONVERSION(unsigned int, uint8_t,
 484                           SIGN_PRESERVING_VALUE_PRESERVING);
 485   TEST_NUMERIC_CONVERSION(int, uint8_t, SIGN_PRESERVING_VALUE_PRESERVING);
 486
 487   TEST_NUMERIC_CONVERSION(int, intmax_t, SIGN_PRESERVING_NARROW);
 488   TEST_NUMERIC_CONVERSION(unsigned int, uintmax_t, SIGN_PRESERVING_NARROW);
 489   TEST_NUMERIC_CONVERSION(int, float, SIGN_PRESERVING_NARROW);
 490   TEST_NUMERIC_CONVERSION(int, double, SIGN_PRESERVING_NARROW);
 491
 492   TEST_NUMERIC_CONVERSION(unsigned int, int, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
 493   TEST_NUMERIC_CONVERSION(unsigned int, int8_t, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
 494
 495   TEST_NUMERIC_CONVERSION(unsigned int, intmax_t, SIGN_TO_UNSIGN_NARROW);
 496   TEST_NUMERIC_CONVERSION(unsigned int, float, SIGN_TO_UNSIGN_NARROW);
 497   TEST_NUMERIC_CONVERSION(unsigned int, double, SIGN_TO_UNSIGN_NARROW);
 498
 499   TEST_NUMERIC_CONVERSION(int, unsigned int, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
 500   TEST_NUMERIC_CONVERSION(int, uintmax_t, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
 501 }
 502
 503 TEST(SafeNumerics, IntMaxOperations) {
 504   TEST_NUMERIC_CONVERSION(intmax_t, intmax_t, SIGN_PRESERVING_VALUE_PRESERVING);
 505   TEST_NUMERIC_CONVERSION(uintmax_t, uintmax_t,
 506                           SIGN_PRESERVING_VALUE_PRESERVING);
 507   TEST_NUMERIC_CONVERSION(intmax_t, int, SIGN_PRESERVING_VALUE_PRESERVING);
 508   TEST_NUMERIC_CONVERSION(uintmax_t, unsigned int,
 509                           SIGN_PRESERVING_VALUE_PRESERVING);
 510   TEST_NUMERIC_CONVERSION(intmax_t, unsigned int,
 511                           SIGN_PRESERVING_VALUE_PRESERVING);
 512   TEST_NUMERIC_CONVERSION(intmax_t, uint8_t, SIGN_PRESERVING_VALUE_PRESERVING);
 513
 514   TEST_NUMERIC_CONVERSION(intmax_t, float, SIGN_PRESERVING_NARROW);
 515   TEST_NUMERIC_CONVERSION(intmax_t, double, SIGN_PRESERVING_NARROW);
 516
 517   TEST_NUMERIC_CONVERSION(uintmax_t, int, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
 518   TEST_NUMERIC_CONVERSION(uintmax_t, int8_t, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
 519
 520   TEST_NUMERIC_CONVERSION(uintmax_t, float, SIGN_TO_UNSIGN_NARROW);
 521   TEST_NUMERIC_CONVERSION(uintmax_t, double, SIGN_TO_UNSIGN_NARROW);
 522
 523   TEST_NUMERIC_CONVERSION(intmax_t, uintmax_t, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
 524 }
 525
 526 TEST(SafeNumerics, FloatOperations) {
 527   TEST_NUMERIC_CONVERSION(float, intmax_t, SIGN_PRESERVING_VALUE_PRESERVING);
 528   TEST_NUMERIC_CONVERSION(float, uintmax_t,
 529                           SIGN_PRESERVING_VALUE_PRESERVING);
 530   TEST_NUMERIC_CONVERSION(float, int, SIGN_PRESERVING_VALUE_PRESERVING);
 531   TEST_NUMERIC_CONVERSION(float, unsigned int,
 532                           SIGN_PRESERVING_VALUE_PRESERVING);
 533
 534   TEST_NUMERIC_CONVERSION(float, double, SIGN_PRESERVING_NARROW);
 535 }
 536
 537 TEST(SafeNumerics, DoubleOperations) {
 538   TEST_NUMERIC_CONVERSION(double, intmax_t, SIGN_PRESERVING_VALUE_PRESERVING);
 539   TEST_NUMERIC_CONVERSION(double, uintmax_t,
 540                           SIGN_PRESERVING_VALUE_PRESERVING);
 541   TEST_NUMERIC_CONVERSION(double, int, SIGN_PRESERVING_VALUE_PRESERVING);
 542   TEST_NUMERIC_CONVERSION(double, unsigned int,
 543                           SIGN_PRESERVING_VALUE_PRESERVING);
 544 }
 545
 546 TEST(SafeNumerics, SizeTOperations) {
 547   TEST_NUMERIC_CONVERSION(size_t, int, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
 548   TEST_NUMERIC_CONVERSION(int, size_t, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
 549 }
 550
 551 TEST(SafeNumerics, CastTests) {
 552 // MSVC catches and warns that we're forcing saturation in these tests.
 553 // Since that's intentional, we need to shut this warning off.
 554 #if defined(COMPILER_MSVC)
 555 #pragma warning(disable : 4756)
 556 #endif
 557
 558   int small_positive = 1;
 559   int small_negative = -1;
 560   double double_small = 1.0;
 561   double double_large = numeric_limits<double>::max();
 562   double double_infinity = numeric_limits<float>::infinity();
 563
 564   // Just test that the cast compiles, since the other tests cover logic.
 565   EXPECT_EQ(0, checked_cast<int>(static_cast<size_t>(0)));
 566
 567   // Test various saturation corner cases.
 568   EXPECT_EQ(saturated_cast<int>(small_negative),
 569             static_cast<int>(small_negative));
 570   EXPECT_EQ(saturated_cast<int>(small_positive),
 571             static_cast<int>(small_positive));
 572   EXPECT_EQ(saturated_cast<unsigned>(small_negative),
 573             static_cast<unsigned>(0));
 574   EXPECT_EQ(saturated_cast<int>(double_small),
 575             static_cast<int>(double_small));
 576   EXPECT_EQ(saturated_cast<int>(double_large), numeric_limits<int>::max());
 577   EXPECT_EQ(saturated_cast<float>(double_large), double_infinity);
 578   EXPECT_EQ(saturated_cast<float>(-double_large), -double_infinity);
 579 }
 580