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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
#include "mozilla/MathAlgorithms.h"
using mozilla::CeilingLog2;
using mozilla::FloorLog2;
using mozilla::RoundUpPow2;
static void TestCeiling() {
for (uint32_t i = 0; i <= 1; i++) {
MOZ_RELEASE_ASSERT(CeilingLog2(i) == 0);
}
for (uint32_t i = 2; i <= 2; i++) {
MOZ_RELEASE_ASSERT(CeilingLog2(i) == 1);
}
for (uint32_t i = 3; i <= 4; i++) {
MOZ_RELEASE_ASSERT(CeilingLog2(i) == 2);
}
for (uint32_t i = 5; i <= 8; i++) {
MOZ_RELEASE_ASSERT(CeilingLog2(i) == 3);
}
for (uint32_t i = 9; i <= 16; i++) {
MOZ_RELEASE_ASSERT(CeilingLog2(i) == 4);
}
}
static void TestFloor() {
for (uint32_t i = 0; i <= 1; i++) {
MOZ_RELEASE_ASSERT(FloorLog2(i) == 0);
}
for (uint32_t i = 2; i <= 3; i++) {
MOZ_RELEASE_ASSERT(FloorLog2(i) == 1);
}
for (uint32_t i = 4; i <= 7; i++) {
MOZ_RELEASE_ASSERT(FloorLog2(i) == 2);
}
for (uint32_t i = 8; i <= 15; i++) {
MOZ_RELEASE_ASSERT(FloorLog2(i) == 3);
}
for (uint32_t i = 16; i <= 31; i++) {
MOZ_RELEASE_ASSERT(FloorLog2(i) == 4);
}
}
static void TestRoundUpPow2() {
MOZ_RELEASE_ASSERT(RoundUpPow2(0) == 1);
MOZ_RELEASE_ASSERT(RoundUpPow2(1) == 1);
MOZ_RELEASE_ASSERT(RoundUpPow2(2) == 2);
MOZ_RELEASE_ASSERT(RoundUpPow2(3) == 4);
MOZ_RELEASE_ASSERT(RoundUpPow2(4) == 4);
MOZ_RELEASE_ASSERT(RoundUpPow2(5) == 8);
MOZ_RELEASE_ASSERT(RoundUpPow2(6) == 8);
MOZ_RELEASE_ASSERT(RoundUpPow2(7) == 8);
MOZ_RELEASE_ASSERT(RoundUpPow2(8) == 8);
MOZ_RELEASE_ASSERT(RoundUpPow2(9) == 16);
MOZ_RELEASE_ASSERT(RoundUpPow2(15) == 16);
MOZ_RELEASE_ASSERT(RoundUpPow2(16) == 16);
MOZ_RELEASE_ASSERT(RoundUpPow2(17) == 32);
MOZ_RELEASE_ASSERT(RoundUpPow2(31) == 32);
MOZ_RELEASE_ASSERT(RoundUpPow2(32) == 32);
MOZ_RELEASE_ASSERT(RoundUpPow2(33) == 64);
size_t MaxPow2 = size_t(1) << (sizeof(size_t) * CHAR_BIT - 1);
MOZ_RELEASE_ASSERT(RoundUpPow2(MaxPow2 - 1) == MaxPow2);
MOZ_RELEASE_ASSERT(RoundUpPow2(MaxPow2) == MaxPow2);
// not valid to round up when past the max power of two
}
int main() {
TestCeiling();
TestFloor();
TestRoundUpPow2();
return 0;
}