| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "net/quic/quic_data_writer.h" |
| |
| #include <stdint.h> |
| |
| #include "base/memory/scoped_ptr.h" |
| #include "net/quic/quic_data_reader.h" |
| #include "net/test/gtest_util.h" |
| #include "testing/gtest/include/gtest/gtest.h" |
| |
| namespace net { |
| namespace test { |
| namespace { |
| |
| TEST(QuicDataWriterTest, SanityCheckUFloat16Consts) { |
| // Check the arithmetic on the constants - otherwise the values below make |
| // no sense. |
| EXPECT_EQ(30, kUFloat16MaxExponent); |
| EXPECT_EQ(11, kUFloat16MantissaBits); |
| EXPECT_EQ(12, kUFloat16MantissaEffectiveBits); |
| EXPECT_EQ(UINT64_C(0x3FFC0000000), kUFloat16MaxValue); |
| } |
| |
| TEST(QuicDataWriterTest, WriteUFloat16) { |
| struct TestCase { |
| uint64_t decoded; |
| uint16_t encoded; |
| }; |
| TestCase test_cases[] = { |
| // Small numbers represent themselves. |
| {0, 0}, |
| {1, 1}, |
| {2, 2}, |
| {3, 3}, |
| {4, 4}, |
| {5, 5}, |
| {6, 6}, |
| {7, 7}, |
| {15, 15}, |
| {31, 31}, |
| {42, 42}, |
| {123, 123}, |
| {1234, 1234}, |
| // Check transition through 2^11. |
| {2046, 2046}, |
| {2047, 2047}, |
| {2048, 2048}, |
| {2049, 2049}, |
| // Running out of mantissa at 2^12. |
| {4094, 4094}, |
| {4095, 4095}, |
| {4096, 4096}, |
| {4097, 4096}, |
| {4098, 4097}, |
| {4099, 4097}, |
| {4100, 4098}, |
| {4101, 4098}, |
| // Check transition through 2^13. |
| {8190, 6143}, |
| {8191, 6143}, |
| {8192, 6144}, |
| {8193, 6144}, |
| {8194, 6144}, |
| {8195, 6144}, |
| {8196, 6145}, |
| {8197, 6145}, |
| // Half-way through the exponents. |
| {0x7FF8000, 0x87FF}, |
| {0x7FFFFFF, 0x87FF}, |
| {0x8000000, 0x8800}, |
| {0xFFF0000, 0x8FFF}, |
| {0xFFFFFFF, 0x8FFF}, |
| {0x10000000, 0x9000}, |
| // Transition into the largest exponent. |
| {0x1FFFFFFFFFE, 0xF7FF}, |
| {0x1FFFFFFFFFF, 0xF7FF}, |
| {0x20000000000, 0xF800}, |
| {0x20000000001, 0xF800}, |
| {0x2003FFFFFFE, 0xF800}, |
| {0x2003FFFFFFF, 0xF800}, |
| {0x20040000000, 0xF801}, |
| {0x20040000001, 0xF801}, |
| // Transition into the max value and clamping. |
| {0x3FF80000000, 0xFFFE}, |
| {0x3FFBFFFFFFF, 0xFFFE}, |
| {0x3FFC0000000, 0xFFFF}, |
| {0x3FFC0000001, 0xFFFF}, |
| {0x3FFFFFFFFFF, 0xFFFF}, |
| {0x40000000000, 0xFFFF}, |
| {0xFFFFFFFFFFFFFFFF, 0xFFFF}, |
| }; |
| int num_test_cases = sizeof(test_cases) / sizeof(test_cases[0]); |
| |
| for (int i = 0; i < num_test_cases; ++i) { |
| char buffer[2]; |
| QuicDataWriter writer(2, buffer); |
| EXPECT_TRUE(writer.WriteUFloat16(test_cases[i].decoded)); |
| EXPECT_EQ(test_cases[i].encoded, |
| *reinterpret_cast<uint16_t*>(writer.data())); |
| } |
| } |
| |
| TEST(QuicDataWriterTest, ReadUFloat16) { |
| struct TestCase { |
| uint64_t decoded; |
| uint16_t encoded; |
| }; |
| TestCase test_cases[] = { |
| // There are fewer decoding test cases because encoding truncates, and |
| // decoding returns the smallest expansion. |
| // Small numbers represent themselves. |
| {0, 0}, |
| {1, 1}, |
| {2, 2}, |
| {3, 3}, |
| {4, 4}, |
| {5, 5}, |
| {6, 6}, |
| {7, 7}, |
| {15, 15}, |
| {31, 31}, |
| {42, 42}, |
| {123, 123}, |
| {1234, 1234}, |
| // Check transition through 2^11. |
| {2046, 2046}, |
| {2047, 2047}, |
| {2048, 2048}, |
| {2049, 2049}, |
| // Running out of mantissa at 2^12. |
| {4094, 4094}, |
| {4095, 4095}, |
| {4096, 4096}, |
| {4098, 4097}, |
| {4100, 4098}, |
| // Check transition through 2^13. |
| {8190, 6143}, |
| {8192, 6144}, |
| {8196, 6145}, |
| // Half-way through the exponents. |
| {0x7FF8000, 0x87FF}, |
| {0x8000000, 0x8800}, |
| {0xFFF0000, 0x8FFF}, |
| {0x10000000, 0x9000}, |
| // Transition into the largest exponent. |
| {0x1FFE0000000, 0xF7FF}, |
| {0x20000000000, 0xF800}, |
| {0x20040000000, 0xF801}, |
| // Transition into the max value. |
| {0x3FF80000000, 0xFFFE}, |
| {0x3FFC0000000, 0xFFFF}, |
| }; |
| int num_test_cases = sizeof(test_cases) / sizeof(test_cases[0]); |
| |
| for (int i = 0; i < num_test_cases; ++i) { |
| QuicDataReader reader(reinterpret_cast<char*>(&test_cases[i].encoded), 2); |
| uint64_t value; |
| EXPECT_TRUE(reader.ReadUFloat16(&value)); |
| EXPECT_EQ(test_cases[i].decoded, value); |
| } |
| } |
| |
| TEST(QuicDataWriterTest, RoundTripUFloat16) { |
| // Just test all 16-bit encoded values. 0 and max already tested above. |
| uint64_t previous_value = 0; |
| for (uint16_t i = 1; i < 0xFFFF; ++i) { |
| // Read the two bytes. |
| QuicDataReader reader(reinterpret_cast<char*>(&i), 2); |
| uint64_t value; |
| // All values must be decodable. |
| EXPECT_TRUE(reader.ReadUFloat16(&value)); |
| // Check that small numbers represent themselves |
| if (i < 4097) |
| EXPECT_EQ(i, value); |
| // Check there's monotonic growth. |
| EXPECT_LT(previous_value, value); |
| // Check that precision is within 0.5% away from the denormals. |
| if (i > 2000) |
| EXPECT_GT(previous_value * 1005, value * 1000); |
| // Check we're always within the promised range. |
| EXPECT_LT(value, UINT64_C(0x3FFC0000000)); |
| previous_value = value; |
| char buffer[6]; |
| QuicDataWriter writer(6, buffer); |
| EXPECT_TRUE(writer.WriteUFloat16(value - 1)); |
| EXPECT_TRUE(writer.WriteUFloat16(value)); |
| EXPECT_TRUE(writer.WriteUFloat16(value + 1)); |
| // Check minimal decoding (previous decoding has previous encoding). |
| EXPECT_EQ(i - 1, *reinterpret_cast<uint16_t*>(writer.data())); |
| // Check roundtrip. |
| EXPECT_EQ(i, *reinterpret_cast<uint16_t*>(writer.data() + 2)); |
| // Check next decoding. |
| EXPECT_EQ(i < 4096 ? i + 1 : i, |
| *reinterpret_cast<uint16_t*>(writer.data() + 4)); |
| } |
| } |
| |
| } // namespace |
| } // namespace test |
| } // namespace net |