1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ 2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */ 3 /* This Source Code Form is subject to the terms of the Mozilla Public 4 * License, v. 2.0. If a copy of the MPL was not distributed with this file, 5 * You can obtain one at http://mozilla.org/MPL/2.0/. */ 6 7 #include "mozilla/MathAlgorithms.h" 8 9 using mozilla::CeilingLog2; 10 using mozilla::FloorLog2; 11 using mozilla::RoundUpPow2; 12 TestCeiling()13static void TestCeiling() { 14 for (uint32_t i = 0; i <= 1; i++) { 15 MOZ_RELEASE_ASSERT(CeilingLog2(i) == 0); 16 } 17 for (uint32_t i = 2; i <= 2; i++) { 18 MOZ_RELEASE_ASSERT(CeilingLog2(i) == 1); 19 } 20 for (uint32_t i = 3; i <= 4; i++) { 21 MOZ_RELEASE_ASSERT(CeilingLog2(i) == 2); 22 } 23 for (uint32_t i = 5; i <= 8; i++) { 24 MOZ_RELEASE_ASSERT(CeilingLog2(i) == 3); 25 } 26 for (uint32_t i = 9; i <= 16; i++) { 27 MOZ_RELEASE_ASSERT(CeilingLog2(i) == 4); 28 } 29 } 30 TestFloor()31static void TestFloor() { 32 for (uint32_t i = 0; i <= 1; i++) { 33 MOZ_RELEASE_ASSERT(FloorLog2(i) == 0); 34 } 35 for (uint32_t i = 2; i <= 3; i++) { 36 MOZ_RELEASE_ASSERT(FloorLog2(i) == 1); 37 } 38 for (uint32_t i = 4; i <= 7; i++) { 39 MOZ_RELEASE_ASSERT(FloorLog2(i) == 2); 40 } 41 for (uint32_t i = 8; i <= 15; i++) { 42 MOZ_RELEASE_ASSERT(FloorLog2(i) == 3); 43 } 44 for (uint32_t i = 16; i <= 31; i++) { 45 MOZ_RELEASE_ASSERT(FloorLog2(i) == 4); 46 } 47 } 48 TestRoundUpPow2()49static void TestRoundUpPow2() { 50 MOZ_RELEASE_ASSERT(RoundUpPow2(0) == 1); 51 MOZ_RELEASE_ASSERT(RoundUpPow2(1) == 1); 52 MOZ_RELEASE_ASSERT(RoundUpPow2(2) == 2); 53 MOZ_RELEASE_ASSERT(RoundUpPow2(3) == 4); 54 MOZ_RELEASE_ASSERT(RoundUpPow2(4) == 4); 55 MOZ_RELEASE_ASSERT(RoundUpPow2(5) == 8); 56 MOZ_RELEASE_ASSERT(RoundUpPow2(6) == 8); 57 MOZ_RELEASE_ASSERT(RoundUpPow2(7) == 8); 58 MOZ_RELEASE_ASSERT(RoundUpPow2(8) == 8); 59 MOZ_RELEASE_ASSERT(RoundUpPow2(9) == 16); 60 61 MOZ_RELEASE_ASSERT(RoundUpPow2(15) == 16); 62 MOZ_RELEASE_ASSERT(RoundUpPow2(16) == 16); 63 MOZ_RELEASE_ASSERT(RoundUpPow2(17) == 32); 64 65 MOZ_RELEASE_ASSERT(RoundUpPow2(31) == 32); 66 MOZ_RELEASE_ASSERT(RoundUpPow2(32) == 32); 67 MOZ_RELEASE_ASSERT(RoundUpPow2(33) == 64); 68 69 size_t MaxPow2 = size_t(1) << (sizeof(size_t) * CHAR_BIT - 1); 70 MOZ_RELEASE_ASSERT(RoundUpPow2(MaxPow2 - 1) == MaxPow2); 71 MOZ_RELEASE_ASSERT(RoundUpPow2(MaxPow2) == MaxPow2); 72 // not valid to round up when past the max power of two 73 } 74 main()75int main() { 76 TestCeiling(); 77 TestFloor(); 78 79 TestRoundUpPow2(); 80 return 0; 81 } 82