396 lines
		
	
	
		
			13 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			396 lines
		
	
	
		
			13 KiB
		
	
	
	
		
			C++
		
	
	
	
| /*
 | |
|  *  Copyright 2016 The WebRTC Project Authors. All rights reserved.
 | |
|  *
 | |
|  *  Use of this source code is governed by a BSD-style license
 | |
|  *  that can be found in the LICENSE file in the root of the source
 | |
|  *  tree. An additional intellectual property rights grant can be found
 | |
|  *  in the file PATENTS.  All contributing project authors may
 | |
|  *  be found in the AUTHORS file in the root of the source tree.
 | |
|  */
 | |
| 
 | |
| #include "rtc_base/numerics/safe_compare.h"
 | |
| 
 | |
| #include <limits>
 | |
| 
 | |
| #include "test/gtest.h"
 | |
| 
 | |
| namespace rtc {
 | |
| 
 | |
| namespace {
 | |
| 
 | |
| constexpr std::uintmax_t umax = std::numeric_limits<std::uintmax_t>::max();
 | |
| constexpr std::intmax_t imin = std::numeric_limits<std::intmax_t>::min();
 | |
| constexpr std::intmax_t m1 = -1;
 | |
| 
 | |
| // m1 and umax have the same representation because we use 2's complement
 | |
| // arithmetic, so naive casting will confuse them.
 | |
| static_assert(static_cast<std::uintmax_t>(m1) == umax, "");
 | |
| static_assert(m1 == static_cast<std::intmax_t>(umax), "");
 | |
| 
 | |
| static const std::pair<int, int> p1(1, 1);
 | |
| static const std::pair<int, int> p2(1, 2);
 | |
| 
 | |
| }  // namespace
 | |
| 
 | |
| // clang-format off
 | |
| 
 | |
| // These functions aren't used in the tests, but it's useful to look at the
 | |
| // compiler output for them, and verify that (1) the same-signedness *Safe
 | |
| // functions result in exactly the same code as their *Ref counterparts, and
 | |
| // that (2) the mixed-signedness *Safe functions have just a few extra
 | |
| // arithmetic and logic instructions (but no extra control flow instructions).
 | |
| bool TestLessThanRef(      int a,      int b) { return a < b; }
 | |
| bool TestLessThanRef( unsigned a, unsigned b) { return a < b; }
 | |
| bool TestLessThanSafe(     int a,      int b) { return SafeLt(a, b); }
 | |
| bool TestLessThanSafe(unsigned a, unsigned b) { return SafeLt(a, b); }
 | |
| bool TestLessThanSafe(unsigned a,      int b) { return SafeLt(a, b); }
 | |
| bool TestLessThanSafe(     int a, unsigned b) { return SafeLt(a, b); }
 | |
| 
 | |
| // For these, we expect the *Ref and *Safe functions to result in identical
 | |
| // code, except for the ones that compare a signed variable with an unsigned
 | |
| // constant; in that case, the *Ref function does an unsigned comparison (fast
 | |
| // but incorrect) and the *Safe function spends a few extra instructions on
 | |
| // doing it right.
 | |
| bool TestLessThan17Ref(       int a) { return a < 17; }
 | |
| bool TestLessThan17Ref(  unsigned a) { return a < 17; }
 | |
| bool TestLessThan17uRef(      int a) { return static_cast<unsigned>(a) < 17u; }
 | |
| bool TestLessThan17uRef( unsigned a) { return a < 17u; }
 | |
| bool TestLessThan17Safe(      int a) { return SafeLt(a, 17); }
 | |
| bool TestLessThan17Safe( unsigned a) { return SafeLt(a, 17); }
 | |
| bool TestLessThan17uSafe(     int a) { return SafeLt(a, 17u); }
 | |
| bool TestLessThan17uSafe(unsigned a) { return SafeLt(a, 17u); }
 | |
| 
 | |
| // Cases where we can't convert to a larger signed type.
 | |
| bool TestLessThanMax( intmax_t a, uintmax_t b) { return SafeLt(a, b); }
 | |
| bool TestLessThanMax(uintmax_t a,  intmax_t b) { return SafeLt(a, b); }
 | |
| bool TestLessThanMax17u( intmax_t a) { return SafeLt(a, uintmax_t{17}); }
 | |
| bool TestLessThanMax17( uintmax_t a) { return SafeLt(a,  intmax_t{17}); }
 | |
| 
 | |
| // Cases where the compiler should be able to compute the result at compile
 | |
| // time.
 | |
| bool TestLessThanConst1() { return SafeLt(  -1,    1); }
 | |
| bool TestLessThanConst2() { return SafeLt(  m1, umax); }
 | |
| bool TestLessThanConst3() { return SafeLt(umax, imin); }
 | |
| bool TestLessThanConst4(unsigned a) { return SafeLt( a, -1); }
 | |
| bool TestLessThanConst5(unsigned a) { return SafeLt(-1,  a); }
 | |
| bool TestLessThanConst6(unsigned a) { return SafeLt( a,  a); }
 | |
| 
 | |
| // clang-format on
 | |
| 
 | |
| TEST(SafeCmpTest, Eq) {
 | |
|   static_assert(!SafeEq(-1, 2), "");
 | |
|   static_assert(!SafeEq(-1, 2u), "");
 | |
|   static_assert(!SafeEq(2, -1), "");
 | |
|   static_assert(!SafeEq(2u, -1), "");
 | |
| 
 | |
|   static_assert(!SafeEq(1, 2), "");
 | |
|   static_assert(!SafeEq(1, 2u), "");
 | |
|   static_assert(!SafeEq(1u, 2), "");
 | |
|   static_assert(!SafeEq(1u, 2u), "");
 | |
|   static_assert(!SafeEq(2, 1), "");
 | |
|   static_assert(!SafeEq(2, 1u), "");
 | |
|   static_assert(!SafeEq(2u, 1), "");
 | |
|   static_assert(!SafeEq(2u, 1u), "");
 | |
| 
 | |
|   static_assert(SafeEq(2, 2), "");
 | |
|   static_assert(SafeEq(2, 2u), "");
 | |
|   static_assert(SafeEq(2u, 2), "");
 | |
|   static_assert(SafeEq(2u, 2u), "");
 | |
| 
 | |
|   static_assert(SafeEq(imin, imin), "");
 | |
|   static_assert(!SafeEq(imin, umax), "");
 | |
|   static_assert(!SafeEq(umax, imin), "");
 | |
|   static_assert(SafeEq(umax, umax), "");
 | |
| 
 | |
|   static_assert(SafeEq(m1, m1), "");
 | |
|   static_assert(!SafeEq(m1, umax), "");
 | |
|   static_assert(!SafeEq(umax, m1), "");
 | |
|   static_assert(SafeEq(umax, umax), "");
 | |
| 
 | |
|   static_assert(!SafeEq(1, 2), "");
 | |
|   static_assert(!SafeEq(1, 2.0), "");
 | |
|   static_assert(!SafeEq(1.0, 2), "");
 | |
|   static_assert(!SafeEq(1.0, 2.0), "");
 | |
|   static_assert(!SafeEq(2, 1), "");
 | |
|   static_assert(!SafeEq(2, 1.0), "");
 | |
|   static_assert(!SafeEq(2.0, 1), "");
 | |
|   static_assert(!SafeEq(2.0, 1.0), "");
 | |
| 
 | |
|   static_assert(SafeEq(2, 2), "");
 | |
|   static_assert(SafeEq(2, 2.0), "");
 | |
|   static_assert(SafeEq(2.0, 2), "");
 | |
|   static_assert(SafeEq(2.0, 2.0), "");
 | |
| 
 | |
|   EXPECT_TRUE(SafeEq(p1, p1));
 | |
|   EXPECT_FALSE(SafeEq(p1, p2));
 | |
|   EXPECT_FALSE(SafeEq(p2, p1));
 | |
|   EXPECT_TRUE(SafeEq(p2, p2));
 | |
| }
 | |
| 
 | |
| TEST(SafeCmpTest, Ne) {
 | |
|   static_assert(SafeNe(-1, 2), "");
 | |
|   static_assert(SafeNe(-1, 2u), "");
 | |
|   static_assert(SafeNe(2, -1), "");
 | |
|   static_assert(SafeNe(2u, -1), "");
 | |
| 
 | |
|   static_assert(SafeNe(1, 2), "");
 | |
|   static_assert(SafeNe(1, 2u), "");
 | |
|   static_assert(SafeNe(1u, 2), "");
 | |
|   static_assert(SafeNe(1u, 2u), "");
 | |
|   static_assert(SafeNe(2, 1), "");
 | |
|   static_assert(SafeNe(2, 1u), "");
 | |
|   static_assert(SafeNe(2u, 1), "");
 | |
|   static_assert(SafeNe(2u, 1u), "");
 | |
| 
 | |
|   static_assert(!SafeNe(2, 2), "");
 | |
|   static_assert(!SafeNe(2, 2u), "");
 | |
|   static_assert(!SafeNe(2u, 2), "");
 | |
|   static_assert(!SafeNe(2u, 2u), "");
 | |
| 
 | |
|   static_assert(!SafeNe(imin, imin), "");
 | |
|   static_assert(SafeNe(imin, umax), "");
 | |
|   static_assert(SafeNe(umax, imin), "");
 | |
|   static_assert(!SafeNe(umax, umax), "");
 | |
| 
 | |
|   static_assert(!SafeNe(m1, m1), "");
 | |
|   static_assert(SafeNe(m1, umax), "");
 | |
|   static_assert(SafeNe(umax, m1), "");
 | |
|   static_assert(!SafeNe(umax, umax), "");
 | |
| 
 | |
|   static_assert(SafeNe(1, 2), "");
 | |
|   static_assert(SafeNe(1, 2.0), "");
 | |
|   static_assert(SafeNe(1.0, 2), "");
 | |
|   static_assert(SafeNe(1.0, 2.0), "");
 | |
|   static_assert(SafeNe(2, 1), "");
 | |
|   static_assert(SafeNe(2, 1.0), "");
 | |
|   static_assert(SafeNe(2.0, 1), "");
 | |
|   static_assert(SafeNe(2.0, 1.0), "");
 | |
| 
 | |
|   static_assert(!SafeNe(2, 2), "");
 | |
|   static_assert(!SafeNe(2, 2.0), "");
 | |
|   static_assert(!SafeNe(2.0, 2), "");
 | |
|   static_assert(!SafeNe(2.0, 2.0), "");
 | |
| 
 | |
|   EXPECT_FALSE(SafeNe(p1, p1));
 | |
|   EXPECT_TRUE(SafeNe(p1, p2));
 | |
|   EXPECT_TRUE(SafeNe(p2, p1));
 | |
|   EXPECT_FALSE(SafeNe(p2, p2));
 | |
| }
 | |
| 
 | |
| TEST(SafeCmpTest, Lt) {
 | |
|   static_assert(SafeLt(-1, 2), "");
 | |
|   static_assert(SafeLt(-1, 2u), "");
 | |
|   static_assert(!SafeLt(2, -1), "");
 | |
|   static_assert(!SafeLt(2u, -1), "");
 | |
| 
 | |
|   static_assert(SafeLt(1, 2), "");
 | |
|   static_assert(SafeLt(1, 2u), "");
 | |
|   static_assert(SafeLt(1u, 2), "");
 | |
|   static_assert(SafeLt(1u, 2u), "");
 | |
|   static_assert(!SafeLt(2, 1), "");
 | |
|   static_assert(!SafeLt(2, 1u), "");
 | |
|   static_assert(!SafeLt(2u, 1), "");
 | |
|   static_assert(!SafeLt(2u, 1u), "");
 | |
| 
 | |
|   static_assert(!SafeLt(2, 2), "");
 | |
|   static_assert(!SafeLt(2, 2u), "");
 | |
|   static_assert(!SafeLt(2u, 2), "");
 | |
|   static_assert(!SafeLt(2u, 2u), "");
 | |
| 
 | |
|   static_assert(!SafeLt(imin, imin), "");
 | |
|   static_assert(SafeLt(imin, umax), "");
 | |
|   static_assert(!SafeLt(umax, imin), "");
 | |
|   static_assert(!SafeLt(umax, umax), "");
 | |
| 
 | |
|   static_assert(!SafeLt(m1, m1), "");
 | |
|   static_assert(SafeLt(m1, umax), "");
 | |
|   static_assert(!SafeLt(umax, m1), "");
 | |
|   static_assert(!SafeLt(umax, umax), "");
 | |
| 
 | |
|   static_assert(SafeLt(1, 2), "");
 | |
|   static_assert(SafeLt(1, 2.0), "");
 | |
|   static_assert(SafeLt(1.0, 2), "");
 | |
|   static_assert(SafeLt(1.0, 2.0), "");
 | |
|   static_assert(!SafeLt(2, 1), "");
 | |
|   static_assert(!SafeLt(2, 1.0), "");
 | |
|   static_assert(!SafeLt(2.0, 1), "");
 | |
|   static_assert(!SafeLt(2.0, 1.0), "");
 | |
| 
 | |
|   static_assert(!SafeLt(2, 2), "");
 | |
|   static_assert(!SafeLt(2, 2.0), "");
 | |
|   static_assert(!SafeLt(2.0, 2), "");
 | |
|   static_assert(!SafeLt(2.0, 2.0), "");
 | |
| 
 | |
|   EXPECT_FALSE(SafeLt(p1, p1));
 | |
|   EXPECT_TRUE(SafeLt(p1, p2));
 | |
|   EXPECT_FALSE(SafeLt(p2, p1));
 | |
|   EXPECT_FALSE(SafeLt(p2, p2));
 | |
| }
 | |
| 
 | |
| TEST(SafeCmpTest, Le) {
 | |
|   static_assert(SafeLe(-1, 2), "");
 | |
|   static_assert(SafeLe(-1, 2u), "");
 | |
|   static_assert(!SafeLe(2, -1), "");
 | |
|   static_assert(!SafeLe(2u, -1), "");
 | |
| 
 | |
|   static_assert(SafeLe(1, 2), "");
 | |
|   static_assert(SafeLe(1, 2u), "");
 | |
|   static_assert(SafeLe(1u, 2), "");
 | |
|   static_assert(SafeLe(1u, 2u), "");
 | |
|   static_assert(!SafeLe(2, 1), "");
 | |
|   static_assert(!SafeLe(2, 1u), "");
 | |
|   static_assert(!SafeLe(2u, 1), "");
 | |
|   static_assert(!SafeLe(2u, 1u), "");
 | |
| 
 | |
|   static_assert(SafeLe(2, 2), "");
 | |
|   static_assert(SafeLe(2, 2u), "");
 | |
|   static_assert(SafeLe(2u, 2), "");
 | |
|   static_assert(SafeLe(2u, 2u), "");
 | |
| 
 | |
|   static_assert(SafeLe(imin, imin), "");
 | |
|   static_assert(SafeLe(imin, umax), "");
 | |
|   static_assert(!SafeLe(umax, imin), "");
 | |
|   static_assert(SafeLe(umax, umax), "");
 | |
| 
 | |
|   static_assert(SafeLe(m1, m1), "");
 | |
|   static_assert(SafeLe(m1, umax), "");
 | |
|   static_assert(!SafeLe(umax, m1), "");
 | |
|   static_assert(SafeLe(umax, umax), "");
 | |
| 
 | |
|   static_assert(SafeLe(1, 2), "");
 | |
|   static_assert(SafeLe(1, 2.0), "");
 | |
|   static_assert(SafeLe(1.0, 2), "");
 | |
|   static_assert(SafeLe(1.0, 2.0), "");
 | |
|   static_assert(!SafeLe(2, 1), "");
 | |
|   static_assert(!SafeLe(2, 1.0), "");
 | |
|   static_assert(!SafeLe(2.0, 1), "");
 | |
|   static_assert(!SafeLe(2.0, 1.0), "");
 | |
| 
 | |
|   static_assert(SafeLe(2, 2), "");
 | |
|   static_assert(SafeLe(2, 2.0), "");
 | |
|   static_assert(SafeLe(2.0, 2), "");
 | |
|   static_assert(SafeLe(2.0, 2.0), "");
 | |
| 
 | |
|   EXPECT_TRUE(SafeLe(p1, p1));
 | |
|   EXPECT_TRUE(SafeLe(p1, p2));
 | |
|   EXPECT_FALSE(SafeLe(p2, p1));
 | |
|   EXPECT_TRUE(SafeLe(p2, p2));
 | |
| }
 | |
| 
 | |
| TEST(SafeCmpTest, Gt) {
 | |
|   static_assert(!SafeGt(-1, 2), "");
 | |
|   static_assert(!SafeGt(-1, 2u), "");
 | |
|   static_assert(SafeGt(2, -1), "");
 | |
|   static_assert(SafeGt(2u, -1), "");
 | |
| 
 | |
|   static_assert(!SafeGt(1, 2), "");
 | |
|   static_assert(!SafeGt(1, 2u), "");
 | |
|   static_assert(!SafeGt(1u, 2), "");
 | |
|   static_assert(!SafeGt(1u, 2u), "");
 | |
|   static_assert(SafeGt(2, 1), "");
 | |
|   static_assert(SafeGt(2, 1u), "");
 | |
|   static_assert(SafeGt(2u, 1), "");
 | |
|   static_assert(SafeGt(2u, 1u), "");
 | |
| 
 | |
|   static_assert(!SafeGt(2, 2), "");
 | |
|   static_assert(!SafeGt(2, 2u), "");
 | |
|   static_assert(!SafeGt(2u, 2), "");
 | |
|   static_assert(!SafeGt(2u, 2u), "");
 | |
| 
 | |
|   static_assert(!SafeGt(imin, imin), "");
 | |
|   static_assert(!SafeGt(imin, umax), "");
 | |
|   static_assert(SafeGt(umax, imin), "");
 | |
|   static_assert(!SafeGt(umax, umax), "");
 | |
| 
 | |
|   static_assert(!SafeGt(m1, m1), "");
 | |
|   static_assert(!SafeGt(m1, umax), "");
 | |
|   static_assert(SafeGt(umax, m1), "");
 | |
|   static_assert(!SafeGt(umax, umax), "");
 | |
| 
 | |
|   static_assert(!SafeGt(1, 2), "");
 | |
|   static_assert(!SafeGt(1, 2.0), "");
 | |
|   static_assert(!SafeGt(1.0, 2), "");
 | |
|   static_assert(!SafeGt(1.0, 2.0), "");
 | |
|   static_assert(SafeGt(2, 1), "");
 | |
|   static_assert(SafeGt(2, 1.0), "");
 | |
|   static_assert(SafeGt(2.0, 1), "");
 | |
|   static_assert(SafeGt(2.0, 1.0), "");
 | |
| 
 | |
|   static_assert(!SafeGt(2, 2), "");
 | |
|   static_assert(!SafeGt(2, 2.0), "");
 | |
|   static_assert(!SafeGt(2.0, 2), "");
 | |
|   static_assert(!SafeGt(2.0, 2.0), "");
 | |
| 
 | |
|   EXPECT_FALSE(SafeGt(p1, p1));
 | |
|   EXPECT_FALSE(SafeGt(p1, p2));
 | |
|   EXPECT_TRUE(SafeGt(p2, p1));
 | |
|   EXPECT_FALSE(SafeGt(p2, p2));
 | |
| }
 | |
| 
 | |
| TEST(SafeCmpTest, Ge) {
 | |
|   static_assert(!SafeGe(-1, 2), "");
 | |
|   static_assert(!SafeGe(-1, 2u), "");
 | |
|   static_assert(SafeGe(2, -1), "");
 | |
|   static_assert(SafeGe(2u, -1), "");
 | |
| 
 | |
|   static_assert(!SafeGe(1, 2), "");
 | |
|   static_assert(!SafeGe(1, 2u), "");
 | |
|   static_assert(!SafeGe(1u, 2), "");
 | |
|   static_assert(!SafeGe(1u, 2u), "");
 | |
|   static_assert(SafeGe(2, 1), "");
 | |
|   static_assert(SafeGe(2, 1u), "");
 | |
|   static_assert(SafeGe(2u, 1), "");
 | |
|   static_assert(SafeGe(2u, 1u), "");
 | |
| 
 | |
|   static_assert(SafeGe(2, 2), "");
 | |
|   static_assert(SafeGe(2, 2u), "");
 | |
|   static_assert(SafeGe(2u, 2), "");
 | |
|   static_assert(SafeGe(2u, 2u), "");
 | |
| 
 | |
|   static_assert(SafeGe(imin, imin), "");
 | |
|   static_assert(!SafeGe(imin, umax), "");
 | |
|   static_assert(SafeGe(umax, imin), "");
 | |
|   static_assert(SafeGe(umax, umax), "");
 | |
| 
 | |
|   static_assert(SafeGe(m1, m1), "");
 | |
|   static_assert(!SafeGe(m1, umax), "");
 | |
|   static_assert(SafeGe(umax, m1), "");
 | |
|   static_assert(SafeGe(umax, umax), "");
 | |
| 
 | |
|   static_assert(!SafeGe(1, 2), "");
 | |
|   static_assert(!SafeGe(1, 2.0), "");
 | |
|   static_assert(!SafeGe(1.0, 2), "");
 | |
|   static_assert(!SafeGe(1.0, 2.0), "");
 | |
|   static_assert(SafeGe(2, 1), "");
 | |
|   static_assert(SafeGe(2, 1.0), "");
 | |
|   static_assert(SafeGe(2.0, 1), "");
 | |
|   static_assert(SafeGe(2.0, 1.0), "");
 | |
| 
 | |
|   static_assert(SafeGe(2, 2), "");
 | |
|   static_assert(SafeGe(2, 2.0), "");
 | |
|   static_assert(SafeGe(2.0, 2), "");
 | |
|   static_assert(SafeGe(2.0, 2.0), "");
 | |
| 
 | |
|   EXPECT_TRUE(SafeGe(p1, p1));
 | |
|   EXPECT_FALSE(SafeGe(p1, p2));
 | |
|   EXPECT_TRUE(SafeGe(p2, p1));
 | |
|   EXPECT_TRUE(SafeGe(p2, p2));
 | |
| }
 | |
| 
 | |
| TEST(SafeCmpTest, Enum) {
 | |
|   enum E1 { e1 = 13 };
 | |
|   enum { e2 = 13 };
 | |
|   enum E3 : unsigned { e3 = 13 };
 | |
|   enum : unsigned { e4 = 13 };
 | |
|   static_assert(SafeEq(13, e1), "");
 | |
|   static_assert(SafeEq(13u, e1), "");
 | |
|   static_assert(SafeEq(13, e2), "");
 | |
|   static_assert(SafeEq(13u, e2), "");
 | |
|   static_assert(SafeEq(13, e3), "");
 | |
|   static_assert(SafeEq(13u, e3), "");
 | |
|   static_assert(SafeEq(13, e4), "");
 | |
|   static_assert(SafeEq(13u, e4), "");
 | |
| }
 | |
| 
 | |
| }  // namespace rtc
 |