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
18using std::numeric_limits;
19using base::CheckedNumeric;
20using base::checked_cast;
21using base::saturated_cast;
22using base::internal::MaxExponent;
23using base::internal::RANGE_VALID;
24using base::internal::RANGE_INVALID;
25using base::internal::RANGE_OVERFLOW;
26using base::internal::RANGE_UNDERFLOW;
27using 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.
31inline void ResetFloatingPointUnit() {
32#if defined(COMPILER_MSVC) && defined(ARCH_CPU_32_BITS)
33  _mm_empty();
34#endif
35}
36
37// These tests deliberately cause arithmetic overflows. If the compiler is
38// aggressive enough, it can const fold these overflows. Disable warnings about
39// overflows for const expressions.
40#if defined(OS_WIN)
41#pragma warning(disable:4756)
42#endif
43
44// Helper macros to wrap displaying the conversion types and line numbers.
45#define TEST_EXPECTED_VALIDITY(expected, actual)                           \
46  EXPECT_EQ(expected, CheckedNumeric<Dst>(actual).validity())              \
47      << "Result test: Value " << +(actual).ValueUnsafe() << " as " << dst \
48      << " on line " << line;
49
50#define TEST_EXPECTED_VALUE(expected, actual)                                \
51  EXPECT_EQ(static_cast<Dst>(expected),                                      \
52            CheckedNumeric<Dst>(actual).ValueUnsafe())                       \
53      << "Result test: Value " << +((actual).ValueUnsafe()) << " as " << dst \
54      << " on line " << line;
55
56// Signed integer arithmetic.
57template <typename Dst>
58static void TestSpecializedArithmetic(
59    const char* dst,
60    int line,
61    typename enable_if<
62        numeric_limits<Dst>::is_integer&& numeric_limits<Dst>::is_signed,
63        int>::type = 0) {
64  typedef numeric_limits<Dst> DstLimits;
65  TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW,
66                         -CheckedNumeric<Dst>(DstLimits::min()));
67  TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW,
68                         CheckedNumeric<Dst>(DstLimits::min()).Abs());
69  TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(-1).Abs());
70
71  TEST_EXPECTED_VALIDITY(RANGE_VALID,
72                         CheckedNumeric<Dst>(DstLimits::max()) + -1);
73  TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW,
74                         CheckedNumeric<Dst>(DstLimits::min()) + -1);
75  TEST_EXPECTED_VALIDITY(
76      RANGE_UNDERFLOW,
77      CheckedNumeric<Dst>(-DstLimits::max()) + -DstLimits::max());
78
79  TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW,
80                         CheckedNumeric<Dst>(DstLimits::min()) - 1);
81  TEST_EXPECTED_VALIDITY(RANGE_VALID,
82                         CheckedNumeric<Dst>(DstLimits::min()) - -1);
83  TEST_EXPECTED_VALIDITY(
84      RANGE_OVERFLOW,
85      CheckedNumeric<Dst>(DstLimits::max()) - -DstLimits::max());
86  TEST_EXPECTED_VALIDITY(
87      RANGE_UNDERFLOW,
88      CheckedNumeric<Dst>(-DstLimits::max()) - DstLimits::max());
89
90  TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW,
91                         CheckedNumeric<Dst>(DstLimits::min()) * 2);
92
93  TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW,
94                         CheckedNumeric<Dst>(DstLimits::min()) / -1);
95  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(-1) / 2);
96
97  // Modulus is legal only for integers.
98  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>() % 1);
99  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % 1);
100  TEST_EXPECTED_VALUE(-1, CheckedNumeric<Dst>(-1) % 2);
101  TEST_EXPECTED_VALIDITY(RANGE_INVALID, CheckedNumeric<Dst>(-1) % -2);
102  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(DstLimits::min()) % 2);
103  TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(DstLimits::max()) % 2);
104  // Test all the different modulus combinations.
105  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % CheckedNumeric<Dst>(1));
106  TEST_EXPECTED_VALUE(0, 1 % CheckedNumeric<Dst>(1));
107  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % 1);
108  CheckedNumeric<Dst> checked_dst = 1;
109  TEST_EXPECTED_VALUE(0, checked_dst %= 1);
110}
111
112// Unsigned integer arithmetic.
113template <typename Dst>
114static void TestSpecializedArithmetic(
115    const char* dst,
116    int line,
117    typename enable_if<
118        numeric_limits<Dst>::is_integer && !numeric_limits<Dst>::is_signed,
119        int>::type = 0) {
120  typedef numeric_limits<Dst> DstLimits;
121  TEST_EXPECTED_VALIDITY(RANGE_VALID, -CheckedNumeric<Dst>(DstLimits::min()));
122  TEST_EXPECTED_VALIDITY(RANGE_VALID,
123                         CheckedNumeric<Dst>(DstLimits::min()).Abs());
124  TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW,
125                         CheckedNumeric<Dst>(DstLimits::min()) + -1);
126  TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW,
127                         CheckedNumeric<Dst>(DstLimits::min()) - 1);
128  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(DstLimits::min()) * 2);
129  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) / 2);
130
131  // Modulus is legal only for integers.
132  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>() % 1);
133  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % 1);
134  TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) % 2);
135  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(DstLimits::min()) % 2);
136  TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(DstLimits::max()) % 2);
137  // Test all the different modulus combinations.
138  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % CheckedNumeric<Dst>(1));
139  TEST_EXPECTED_VALUE(0, 1 % CheckedNumeric<Dst>(1));
140  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) % 1);
141  CheckedNumeric<Dst> checked_dst = 1;
142  TEST_EXPECTED_VALUE(0, checked_dst %= 1);
143}
144
145// Floating point arithmetic.
146template <typename Dst>
147void TestSpecializedArithmetic(
148    const char* dst,
149    int line,
150    typename enable_if<numeric_limits<Dst>::is_iec559, int>::type = 0) {
151  typedef numeric_limits<Dst> DstLimits;
152  TEST_EXPECTED_VALIDITY(RANGE_VALID, -CheckedNumeric<Dst>(DstLimits::min()));
153
154  TEST_EXPECTED_VALIDITY(RANGE_VALID,
155                         CheckedNumeric<Dst>(DstLimits::min()).Abs());
156  TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(-1).Abs());
157
158  TEST_EXPECTED_VALIDITY(RANGE_VALID,
159                         CheckedNumeric<Dst>(DstLimits::min()) + -1);
160  TEST_EXPECTED_VALIDITY(RANGE_VALID,
161                         CheckedNumeric<Dst>(DstLimits::max()) + 1);
162  TEST_EXPECTED_VALIDITY(
163      RANGE_UNDERFLOW,
164      CheckedNumeric<Dst>(-DstLimits::max()) + -DstLimits::max());
165
166  TEST_EXPECTED_VALIDITY(
167      RANGE_OVERFLOW,
168      CheckedNumeric<Dst>(DstLimits::max()) - -DstLimits::max());
169  TEST_EXPECTED_VALIDITY(
170      RANGE_UNDERFLOW,
171      CheckedNumeric<Dst>(-DstLimits::max()) - DstLimits::max());
172
173  TEST_EXPECTED_VALIDITY(RANGE_VALID,
174                         CheckedNumeric<Dst>(DstLimits::min()) * 2);
175
176  TEST_EXPECTED_VALUE(-0.5, CheckedNumeric<Dst>(-1.0) / 2);
177  EXPECT_EQ(static_cast<Dst>(1.0), CheckedNumeric<Dst>(1.0).ValueFloating());
178}
179
180// Generic arithmetic tests.
181template <typename Dst>
182static void TestArithmetic(const char* dst, int line) {
183  typedef numeric_limits<Dst> DstLimits;
184
185  EXPECT_EQ(true, CheckedNumeric<Dst>().IsValid());
186  EXPECT_EQ(false,
187            CheckedNumeric<Dst>(CheckedNumeric<Dst>(DstLimits::max()) *
188                                DstLimits::max()).IsValid());
189  EXPECT_EQ(static_cast<Dst>(0), CheckedNumeric<Dst>().ValueOrDie());
190  EXPECT_EQ(static_cast<Dst>(0), CheckedNumeric<Dst>().ValueOrDefault(1));
191  EXPECT_EQ(static_cast<Dst>(1),
192            CheckedNumeric<Dst>(CheckedNumeric<Dst>(DstLimits::max()) *
193                                DstLimits::max()).ValueOrDefault(1));
194
195  // Test the operator combinations.
196  TEST_EXPECTED_VALUE(2, CheckedNumeric<Dst>(1) + CheckedNumeric<Dst>(1));
197  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) - CheckedNumeric<Dst>(1));
198  TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) * CheckedNumeric<Dst>(1));
199  TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) / CheckedNumeric<Dst>(1));
200  TEST_EXPECTED_VALUE(2, 1 + CheckedNumeric<Dst>(1));
201  TEST_EXPECTED_VALUE(0, 1 - CheckedNumeric<Dst>(1));
202  TEST_EXPECTED_VALUE(1, 1 * CheckedNumeric<Dst>(1));
203  TEST_EXPECTED_VALUE(1, 1 / CheckedNumeric<Dst>(1));
204  TEST_EXPECTED_VALUE(2, CheckedNumeric<Dst>(1) + 1);
205  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>(1) - 1);
206  TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) * 1);
207  TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) / 1);
208  CheckedNumeric<Dst> checked_dst = 1;
209  TEST_EXPECTED_VALUE(2, checked_dst += 1);
210  checked_dst = 1;
211  TEST_EXPECTED_VALUE(0, checked_dst -= 1);
212  checked_dst = 1;
213  TEST_EXPECTED_VALUE(1, checked_dst *= 1);
214  checked_dst = 1;
215  TEST_EXPECTED_VALUE(1, checked_dst /= 1);
216
217  // Generic negation.
218  TEST_EXPECTED_VALUE(0, -CheckedNumeric<Dst>());
219  TEST_EXPECTED_VALUE(-1, -CheckedNumeric<Dst>(1));
220  TEST_EXPECTED_VALUE(1, -CheckedNumeric<Dst>(-1));
221  TEST_EXPECTED_VALUE(static_cast<Dst>(DstLimits::max() * -1),
222                      -CheckedNumeric<Dst>(DstLimits::max()));
223
224  // Generic absolute value.
225  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>().Abs());
226  TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1).Abs());
227  TEST_EXPECTED_VALUE(DstLimits::max(),
228                      CheckedNumeric<Dst>(DstLimits::max()).Abs());
229
230  // Generic addition.
231  TEST_EXPECTED_VALUE(1, (CheckedNumeric<Dst>() + 1));
232  TEST_EXPECTED_VALUE(2, (CheckedNumeric<Dst>(1) + 1));
233  TEST_EXPECTED_VALUE(0, (CheckedNumeric<Dst>(-1) + 1));
234  TEST_EXPECTED_VALIDITY(RANGE_VALID,
235                         CheckedNumeric<Dst>(DstLimits::min()) + 1);
236  TEST_EXPECTED_VALIDITY(
237      RANGE_OVERFLOW, CheckedNumeric<Dst>(DstLimits::max()) + DstLimits::max());
238
239  // Generic subtraction.
240  TEST_EXPECTED_VALUE(-1, (CheckedNumeric<Dst>() - 1));
241  TEST_EXPECTED_VALUE(0, (CheckedNumeric<Dst>(1) - 1));
242  TEST_EXPECTED_VALUE(-2, (CheckedNumeric<Dst>(-1) - 1));
243  TEST_EXPECTED_VALIDITY(RANGE_VALID,
244                         CheckedNumeric<Dst>(DstLimits::max()) - 1);
245
246  // Generic multiplication.
247  TEST_EXPECTED_VALUE(0, (CheckedNumeric<Dst>() * 1));
248  TEST_EXPECTED_VALUE(1, (CheckedNumeric<Dst>(1) * 1));
249  TEST_EXPECTED_VALUE(-2, (CheckedNumeric<Dst>(-1) * 2));
250  TEST_EXPECTED_VALIDITY(
251      RANGE_OVERFLOW, CheckedNumeric<Dst>(DstLimits::max()) * DstLimits::max());
252
253  // Generic division.
254  TEST_EXPECTED_VALUE(0, CheckedNumeric<Dst>() / 1);
255  TEST_EXPECTED_VALUE(1, CheckedNumeric<Dst>(1) / 1);
256  TEST_EXPECTED_VALUE(DstLimits::min() / 2,
257                      CheckedNumeric<Dst>(DstLimits::min()) / 2);
258  TEST_EXPECTED_VALUE(DstLimits::max() / 2,
259                      CheckedNumeric<Dst>(DstLimits::max()) / 2);
260
261  TestSpecializedArithmetic<Dst>(dst, line);
262}
263
264// Helper macro to wrap displaying the conversion types and line numbers.
265#define TEST_ARITHMETIC(Dst) TestArithmetic<Dst>(#Dst, __LINE__)
266
267TEST(SafeNumerics, SignedIntegerMath) {
268  TEST_ARITHMETIC(int8_t);
269  TEST_ARITHMETIC(int);
270  TEST_ARITHMETIC(intptr_t);
271  TEST_ARITHMETIC(intmax_t);
272}
273
274TEST(SafeNumerics, UnsignedIntegerMath) {
275  TEST_ARITHMETIC(uint8_t);
276  TEST_ARITHMETIC(unsigned int);
277  TEST_ARITHMETIC(uintptr_t);
278  TEST_ARITHMETIC(uintmax_t);
279}
280
281TEST(SafeNumerics, FloatingPointMath) {
282  TEST_ARITHMETIC(float);
283  TEST_ARITHMETIC(double);
284}
285
286// Enumerates the five different conversions types we need to test.
287enum NumericConversionType {
288  SIGN_PRESERVING_VALUE_PRESERVING,
289  SIGN_PRESERVING_NARROW,
290  SIGN_TO_UNSIGN_WIDEN_OR_EQUAL,
291  SIGN_TO_UNSIGN_NARROW,
292  UNSIGN_TO_SIGN_NARROW_OR_EQUAL,
293};
294
295// Template covering the different conversion tests.
296template <typename Dst, typename Src, NumericConversionType conversion>
297struct TestNumericConversion {};
298
299// EXPECT_EQ wrappers providing specific detail on test failures.
300#define TEST_EXPECTED_RANGE(expected, actual)                                  \
301  EXPECT_EQ(expected, base::internal::DstRangeRelationToSrcRange<Dst>(actual)) \
302      << "Conversion test: " << src << " value " << actual << " to " << dst    \
303      << " on line " << line;
304
305template <typename Dst, typename Src>
306struct TestNumericConversion<Dst, Src, SIGN_PRESERVING_VALUE_PRESERVING> {
307  static void Test(const char *dst, const char *src, int line) {
308    typedef numeric_limits<Src> SrcLimits;
309    typedef numeric_limits<Dst> DstLimits;
310                   // Integral to floating.
311    COMPILE_ASSERT((DstLimits::is_iec559 && SrcLimits::is_integer) ||
312                   // Not floating to integral and...
313                   (!(DstLimits::is_integer && SrcLimits::is_iec559) &&
314                    // Same sign, same numeric, source is narrower or same.
315                    ((SrcLimits::is_signed == DstLimits::is_signed &&
316                     sizeof(Dst) >= sizeof(Src)) ||
317                    // Or signed destination and source is smaller
318                     (DstLimits::is_signed && sizeof(Dst) > sizeof(Src)))),
319                   comparison_must_be_sign_preserving_and_value_preserving);
320
321    const CheckedNumeric<Dst> checked_dst = SrcLimits::max();
322    ;
323    TEST_EXPECTED_VALIDITY(RANGE_VALID, checked_dst);
324    if (MaxExponent<Dst>::value > MaxExponent<Src>::value) {
325      if (MaxExponent<Dst>::value >= MaxExponent<Src>::value * 2 - 1) {
326        // At least twice larger type.
327        TEST_EXPECTED_VALIDITY(RANGE_VALID, SrcLimits::max() * checked_dst);
328
329      } else {  // Larger, but not at least twice as large.
330        TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW, SrcLimits::max() * checked_dst);
331        TEST_EXPECTED_VALIDITY(RANGE_VALID, checked_dst + 1);
332      }
333    } else {  // Same width type.
334      TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW, checked_dst + 1);
335    }
336
337    TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::max());
338    TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(1));
339    if (SrcLimits::is_iec559) {
340      TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::max() * static_cast<Src>(-1));
341      TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::infinity());
342      TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::infinity() * -1);
343      TEST_EXPECTED_RANGE(RANGE_INVALID, SrcLimits::quiet_NaN());
344      ResetFloatingPointUnit();
345    } else if (numeric_limits<Src>::is_signed) {
346      TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(-1));
347      TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::min());
348    }
349  }
350};
351
352template <typename Dst, typename Src>
353struct TestNumericConversion<Dst, Src, SIGN_PRESERVING_NARROW> {
354  static void Test(const char *dst, const char *src, int line) {
355    typedef numeric_limits<Src> SrcLimits;
356    typedef numeric_limits<Dst> DstLimits;
357    COMPILE_ASSERT(SrcLimits::is_signed == DstLimits::is_signed,
358                   destination_and_source_sign_must_be_the_same);
359    COMPILE_ASSERT(sizeof(Dst) < sizeof(Src) ||
360                   (DstLimits::is_integer && SrcLimits::is_iec559),
361                   destination_must_be_narrower_than_source);
362
363    const CheckedNumeric<Dst> checked_dst;
364    TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW, checked_dst + SrcLimits::max());
365    TEST_EXPECTED_VALUE(1, checked_dst + static_cast<Src>(1));
366    TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW, checked_dst - SrcLimits::max());
367
368    TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::max());
369    TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(1));
370    if (SrcLimits::is_iec559) {
371      TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::max() * -1);
372      TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(-1));
373      TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::infinity());
374      TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::infinity() * -1);
375      TEST_EXPECTED_RANGE(RANGE_INVALID, SrcLimits::quiet_NaN());
376      ResetFloatingPointUnit();
377    } else if (SrcLimits::is_signed) {
378      TEST_EXPECTED_VALUE(-1, checked_dst - static_cast<Src>(1));
379      TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::min());
380      TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(-1));
381    } else {
382      TEST_EXPECTED_VALIDITY(RANGE_INVALID, checked_dst - static_cast<Src>(1));
383      TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::min());
384    }
385  }
386};
387
388template <typename Dst, typename Src>
389struct TestNumericConversion<Dst, Src, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL> {
390  static void Test(const char *dst, const char *src, int line) {
391    typedef numeric_limits<Src> SrcLimits;
392    typedef numeric_limits<Dst> DstLimits;
393    COMPILE_ASSERT(sizeof(Dst) >= sizeof(Src),
394                   destination_must_be_equal_or_wider_than_source);
395    COMPILE_ASSERT(SrcLimits::is_signed, source_must_be_signed);
396    COMPILE_ASSERT(!DstLimits::is_signed, destination_must_be_unsigned);
397
398    const CheckedNumeric<Dst> checked_dst;
399    TEST_EXPECTED_VALUE(SrcLimits::max(), checked_dst + SrcLimits::max());
400    TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW, checked_dst + static_cast<Src>(-1));
401    TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW, checked_dst + -SrcLimits::max());
402
403    TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::min());
404    TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::max());
405    TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(1));
406    TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, static_cast<Src>(-1));
407  }
408};
409
410template <typename Dst, typename Src>
411struct TestNumericConversion<Dst, Src, SIGN_TO_UNSIGN_NARROW> {
412  static void Test(const char *dst, const char *src, int line) {
413    typedef numeric_limits<Src> SrcLimits;
414    typedef numeric_limits<Dst> DstLimits;
415    COMPILE_ASSERT((DstLimits::is_integer && SrcLimits::is_iec559) ||
416                   (sizeof(Dst) < sizeof(Src)),
417      destination_must_be_narrower_than_source);
418    COMPILE_ASSERT(SrcLimits::is_signed, source_must_be_signed);
419    COMPILE_ASSERT(!DstLimits::is_signed, destination_must_be_unsigned);
420
421    const CheckedNumeric<Dst> checked_dst;
422    TEST_EXPECTED_VALUE(1, checked_dst + static_cast<Src>(1));
423    TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW, checked_dst + SrcLimits::max());
424    TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW, checked_dst + static_cast<Src>(-1));
425    TEST_EXPECTED_VALIDITY(RANGE_UNDERFLOW, checked_dst + -SrcLimits::max());
426
427    TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::max());
428    TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(1));
429    TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, static_cast<Src>(-1));
430    if (SrcLimits::is_iec559) {
431      TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::max() * -1);
432      TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::infinity());
433      TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::infinity() * -1);
434      TEST_EXPECTED_RANGE(RANGE_INVALID, SrcLimits::quiet_NaN());
435      ResetFloatingPointUnit();
436    } else {
437      TEST_EXPECTED_RANGE(RANGE_UNDERFLOW, SrcLimits::min());
438    }
439  }
440};
441
442template <typename Dst, typename Src>
443struct TestNumericConversion<Dst, Src, UNSIGN_TO_SIGN_NARROW_OR_EQUAL> {
444  static void Test(const char *dst, const char *src, int line) {
445    typedef numeric_limits<Src> SrcLimits;
446    typedef numeric_limits<Dst> DstLimits;
447    COMPILE_ASSERT(sizeof(Dst) <= sizeof(Src),
448                   destination_must_be_narrower_or_equal_to_source);
449    COMPILE_ASSERT(!SrcLimits::is_signed, source_must_be_unsigned);
450    COMPILE_ASSERT(DstLimits::is_signed, destination_must_be_signed);
451
452    const CheckedNumeric<Dst> checked_dst;
453    TEST_EXPECTED_VALUE(1, checked_dst + static_cast<Src>(1));
454    TEST_EXPECTED_VALIDITY(RANGE_OVERFLOW, checked_dst + SrcLimits::max());
455    TEST_EXPECTED_VALUE(SrcLimits::min(), checked_dst + SrcLimits::min());
456
457    TEST_EXPECTED_RANGE(RANGE_VALID, SrcLimits::min());
458    TEST_EXPECTED_RANGE(RANGE_OVERFLOW, SrcLimits::max());
459    TEST_EXPECTED_RANGE(RANGE_VALID, static_cast<Src>(1));
460  }
461};
462
463// Helper macro to wrap displaying the conversion types and line numbers
464#define TEST_NUMERIC_CONVERSION(d, s, t) \
465  TestNumericConversion<d, s, t>::Test(#d, #s, __LINE__)
466
467TEST(SafeNumerics, IntMinOperations) {
468  TEST_NUMERIC_CONVERSION(int8_t, int8_t, SIGN_PRESERVING_VALUE_PRESERVING);
469  TEST_NUMERIC_CONVERSION(uint8_t, uint8_t, SIGN_PRESERVING_VALUE_PRESERVING);
470
471  TEST_NUMERIC_CONVERSION(int8_t, int, SIGN_PRESERVING_NARROW);
472  TEST_NUMERIC_CONVERSION(uint8_t, unsigned int, SIGN_PRESERVING_NARROW);
473  TEST_NUMERIC_CONVERSION(int8_t, float, SIGN_PRESERVING_NARROW);
474
475  TEST_NUMERIC_CONVERSION(uint8_t, int8_t, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
476
477  TEST_NUMERIC_CONVERSION(uint8_t, int, SIGN_TO_UNSIGN_NARROW);
478  TEST_NUMERIC_CONVERSION(uint8_t, intmax_t, SIGN_TO_UNSIGN_NARROW);
479  TEST_NUMERIC_CONVERSION(uint8_t, float, SIGN_TO_UNSIGN_NARROW);
480
481  TEST_NUMERIC_CONVERSION(int8_t, unsigned int, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
482  TEST_NUMERIC_CONVERSION(int8_t, uintmax_t, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
483}
484
485TEST(SafeNumerics, IntOperations) {
486  TEST_NUMERIC_CONVERSION(int, int, SIGN_PRESERVING_VALUE_PRESERVING);
487  TEST_NUMERIC_CONVERSION(unsigned int, unsigned int,
488                          SIGN_PRESERVING_VALUE_PRESERVING);
489  TEST_NUMERIC_CONVERSION(int, int8_t, SIGN_PRESERVING_VALUE_PRESERVING);
490  TEST_NUMERIC_CONVERSION(unsigned int, uint8_t,
491                          SIGN_PRESERVING_VALUE_PRESERVING);
492  TEST_NUMERIC_CONVERSION(int, uint8_t, SIGN_PRESERVING_VALUE_PRESERVING);
493
494  TEST_NUMERIC_CONVERSION(int, intmax_t, SIGN_PRESERVING_NARROW);
495  TEST_NUMERIC_CONVERSION(unsigned int, uintmax_t, SIGN_PRESERVING_NARROW);
496  TEST_NUMERIC_CONVERSION(int, float, SIGN_PRESERVING_NARROW);
497  TEST_NUMERIC_CONVERSION(int, double, SIGN_PRESERVING_NARROW);
498
499  TEST_NUMERIC_CONVERSION(unsigned int, int, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
500  TEST_NUMERIC_CONVERSION(unsigned int, int8_t, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
501
502  TEST_NUMERIC_CONVERSION(unsigned int, intmax_t, SIGN_TO_UNSIGN_NARROW);
503  TEST_NUMERIC_CONVERSION(unsigned int, float, SIGN_TO_UNSIGN_NARROW);
504  TEST_NUMERIC_CONVERSION(unsigned int, double, SIGN_TO_UNSIGN_NARROW);
505
506  TEST_NUMERIC_CONVERSION(int, unsigned int, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
507  TEST_NUMERIC_CONVERSION(int, uintmax_t, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
508}
509
510TEST(SafeNumerics, IntMaxOperations) {
511  TEST_NUMERIC_CONVERSION(intmax_t, intmax_t, SIGN_PRESERVING_VALUE_PRESERVING);
512  TEST_NUMERIC_CONVERSION(uintmax_t, uintmax_t,
513                          SIGN_PRESERVING_VALUE_PRESERVING);
514  TEST_NUMERIC_CONVERSION(intmax_t, int, SIGN_PRESERVING_VALUE_PRESERVING);
515  TEST_NUMERIC_CONVERSION(uintmax_t, unsigned int,
516                          SIGN_PRESERVING_VALUE_PRESERVING);
517  TEST_NUMERIC_CONVERSION(intmax_t, unsigned int,
518                          SIGN_PRESERVING_VALUE_PRESERVING);
519  TEST_NUMERIC_CONVERSION(intmax_t, uint8_t, SIGN_PRESERVING_VALUE_PRESERVING);
520
521  TEST_NUMERIC_CONVERSION(intmax_t, float, SIGN_PRESERVING_NARROW);
522  TEST_NUMERIC_CONVERSION(intmax_t, double, SIGN_PRESERVING_NARROW);
523
524  TEST_NUMERIC_CONVERSION(uintmax_t, int, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
525  TEST_NUMERIC_CONVERSION(uintmax_t, int8_t, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
526
527  TEST_NUMERIC_CONVERSION(uintmax_t, float, SIGN_TO_UNSIGN_NARROW);
528  TEST_NUMERIC_CONVERSION(uintmax_t, double, SIGN_TO_UNSIGN_NARROW);
529
530  TEST_NUMERIC_CONVERSION(intmax_t, uintmax_t, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
531}
532
533TEST(SafeNumerics, FloatOperations) {
534  TEST_NUMERIC_CONVERSION(float, intmax_t, SIGN_PRESERVING_VALUE_PRESERVING);
535  TEST_NUMERIC_CONVERSION(float, uintmax_t,
536                          SIGN_PRESERVING_VALUE_PRESERVING);
537  TEST_NUMERIC_CONVERSION(float, int, SIGN_PRESERVING_VALUE_PRESERVING);
538  TEST_NUMERIC_CONVERSION(float, unsigned int,
539                          SIGN_PRESERVING_VALUE_PRESERVING);
540
541  TEST_NUMERIC_CONVERSION(float, double, SIGN_PRESERVING_NARROW);
542}
543
544TEST(SafeNumerics, DoubleOperations) {
545  TEST_NUMERIC_CONVERSION(double, intmax_t, SIGN_PRESERVING_VALUE_PRESERVING);
546  TEST_NUMERIC_CONVERSION(double, uintmax_t,
547                          SIGN_PRESERVING_VALUE_PRESERVING);
548  TEST_NUMERIC_CONVERSION(double, int, SIGN_PRESERVING_VALUE_PRESERVING);
549  TEST_NUMERIC_CONVERSION(double, unsigned int,
550                          SIGN_PRESERVING_VALUE_PRESERVING);
551}
552
553TEST(SafeNumerics, SizeTOperations) {
554  TEST_NUMERIC_CONVERSION(size_t, int, SIGN_TO_UNSIGN_WIDEN_OR_EQUAL);
555  TEST_NUMERIC_CONVERSION(int, size_t, UNSIGN_TO_SIGN_NARROW_OR_EQUAL);
556}
557
558TEST(SafeNumerics, CastTests) {
559// MSVC catches and warns that we're forcing saturation in these tests.
560// Since that's intentional, we need to shut this warning off.
561#if defined(COMPILER_MSVC)
562#pragma warning(disable : 4756)
563#endif
564
565  int small_positive = 1;
566  int small_negative = -1;
567  double double_small = 1.0;
568  double double_large = numeric_limits<double>::max();
569  double double_infinity = numeric_limits<float>::infinity();
570
571  // Just test that the cast compiles, since the other tests cover logic.
572  EXPECT_EQ(0, checked_cast<int>(static_cast<size_t>(0)));
573
574  // Test various saturation corner cases.
575  EXPECT_EQ(saturated_cast<int>(small_negative),
576            static_cast<int>(small_negative));
577  EXPECT_EQ(saturated_cast<int>(small_positive),
578            static_cast<int>(small_positive));
579  EXPECT_EQ(saturated_cast<unsigned>(small_negative),
580            static_cast<unsigned>(0));
581  EXPECT_EQ(saturated_cast<int>(double_small),
582            static_cast<int>(double_small));
583  EXPECT_EQ(saturated_cast<int>(double_large), numeric_limits<int>::max());
584  EXPECT_EQ(saturated_cast<float>(double_large), double_infinity);
585  EXPECT_EQ(saturated_cast<float>(-double_large), -double_infinity);
586}
587
588