diff options
author | rch@chromium.org <rch@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> | 2012-11-16 07:49:44 +0000 |
---|---|---|
committer | rch@chromium.org <rch@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> | 2012-11-16 07:49:44 +0000 |
commit | 165e075e714fdeaf93b5b4bedb4edcfbe69a0880 (patch) | |
tree | 1b6375e7bd44767f55789648d3b70c55178559b2 /net/base | |
parent | 65bfb61c032e78f7315a971223fd5aa942e4da99 (diff) | |
download | chromium_src-165e075e714fdeaf93b5b4bedb4edcfbe69a0880.zip chromium_src-165e075e714fdeaf93b5b4bedb4edcfbe69a0880.tar.gz chromium_src-165e075e714fdeaf93b5b4bedb4edcfbe69a0880.tar.bz2 |
Add real support for uint128. These files originated with google internally, and since they are shared, the style is a bit different. Removed SWIG support and references to other internal classes.
Review URL: https://chromiumcodereview.appspot.com/11299023
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@168161 0039d316-1c4b-4281-b951-d872f2087c98
Diffstat (limited to 'net/base')
-rw-r--r-- | net/base/int128.cc | 16 | ||||
-rw-r--r-- | net/base/int128.h | 330 | ||||
-rw-r--r-- | net/base/int128_unittest.cc | 265 |
3 files changed, 611 insertions, 0 deletions
diff --git a/net/base/int128.cc b/net/base/int128.cc new file mode 100644 index 0000000..745d8ed --- /dev/null +++ b/net/base/int128.cc @@ -0,0 +1,16 @@ +// 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 <iostream> +#include "base/basictypes.h" +#include "net/base/int128.h" + +const uint128_pod kuint128max = { + static_cast<uint64>(GG_LONGLONG(0xFFFFFFFFFFFFFFFF)), + static_cast<uint64>(GG_LONGLONG(0xFFFFFFFFFFFFFFFF)) +}; + +std::ostream& operator<<(std::ostream& o, const uint128& b) { + return (o << b.hi_ << "::" << b.lo_); +} diff --git a/net/base/int128.h b/net/base/int128.h new file mode 100644 index 0000000..b17801be --- /dev/null +++ b/net/base/int128.h @@ -0,0 +1,330 @@ +// 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. + +#ifndef NET_BASE_INT128_H_ +#define NET_BASE_INT128_H_ + +#include <iosfwd> +#include "base/basictypes.h" +#include "net/base/net_export.h" + +struct uint128_pod; + +// An unsigned 128-bit integer type. Thread-compatible. +class uint128 { +public: + uint128(); // Sets to 0, but don't trust on this behavior. + uint128(uint64 top, uint64 bottom); + uint128(int bottom); + uint128(uint32 bottom); // Top 96 bits = 0 + uint128(uint64 bottom); // hi_ = 0 + uint128(const uint128 &val); + uint128(const uint128_pod &val); + + void Initialize(uint64 top, uint64 bottom); + + uint128& operator=(const uint128& b); + + // Arithmetic operators. + // TODO: division, etc. + uint128& operator+=(const uint128& b); + uint128& operator-=(const uint128& b); + uint128& operator*=(const uint128& b); + uint128 operator++(int); + uint128 operator--(int); + uint128& operator<<=(int); + uint128& operator>>=(int); + uint128& operator&=(const uint128& b); + uint128& operator|=(const uint128& b); + uint128& operator^=(const uint128& b); + uint128& operator++(); + uint128& operator--(); + + friend uint64 Uint128Low64(const uint128& v); + friend uint64 Uint128High64(const uint128& v); + + // We add "std::" to avoid including all of port.h. + friend NET_EXPORT_PRIVATE std::ostream& operator<<(std::ostream& o, + const uint128& b); + +private: + // Little-endian memory order optimizations can benefit from + // having lo_ first, hi_ last. + // See util/endian/endian.h and Load128/Store128 for storing a uint128. + uint64 lo_; + uint64 hi_; + + // Not implemented, just declared for catching automatic type conversions. + uint128(uint8); + uint128(uint16); + uint128(float v); + uint128(double v); +}; + +// This is a POD form of uint128 which can be used for static variables which +// need to be operated on as uint128. +struct uint128_pod { + // Note: The ordering of fields is different than 'class uint128' but the + // same as its 2-arg constructor. This enables more obvious initialization + // of static instances, which is the primary reason for this struct in the + // first place. This does not seem to defeat any optimizations wrt + // operations involving this struct. + uint64 hi; + uint64 lo; +}; + +NET_EXPORT_PRIVATE extern const uint128_pod kuint128max; + +// allow uint128 to be logged +NET_EXPORT_PRIVATE extern std::ostream& operator<<(std::ostream& o, + const uint128& b); + +// Methods to access low and high pieces of 128-bit value. +// Defined externally from uint128 to facilitate conversion +// to native 128-bit types when compilers support them. +inline uint64 Uint128Low64(const uint128& v) { return v.lo_; } +inline uint64 Uint128High64(const uint128& v) { return v.hi_; } + +// TODO: perhaps it would be nice to have int128, a signed 128-bit type? + +// -------------------------------------------------------------------------- +// Implementation details follow +// -------------------------------------------------------------------------- +inline bool operator==(const uint128& lhs, const uint128& rhs) { + return (Uint128Low64(lhs) == Uint128Low64(rhs) && + Uint128High64(lhs) == Uint128High64(rhs)); +} +inline bool operator!=(const uint128& lhs, const uint128& rhs) { + return !(lhs == rhs); +} +inline uint128& uint128::operator=(const uint128& b) { + lo_ = b.lo_; + hi_ = b.hi_; + return *this; +} + +inline uint128::uint128(): lo_(0), hi_(0) { } +inline uint128::uint128(uint64 top, uint64 bottom) : lo_(bottom), hi_(top) { } +inline uint128::uint128(const uint128 &v) : lo_(v.lo_), hi_(v.hi_) { } +inline uint128::uint128(const uint128_pod &v) : lo_(v.lo), hi_(v.hi) { } +inline uint128::uint128(uint64 bottom) : lo_(bottom), hi_(0) { } +inline uint128::uint128(uint32 bottom) : lo_(bottom), hi_(0) { } +inline uint128::uint128(int bottom) : lo_(bottom), hi_(0) { + if (bottom < 0) { + --hi_; + } +} +inline void uint128::Initialize(uint64 top, uint64 bottom) { + hi_ = top; + lo_ = bottom; +} + +// Comparison operators. + +#define CMP128(op) \ +inline bool operator op(const uint128& lhs, const uint128& rhs) { \ + return (Uint128High64(lhs) == Uint128High64(rhs)) ? \ + (Uint128Low64(lhs) op Uint128Low64(rhs)) : \ + (Uint128High64(lhs) op Uint128High64(rhs)); \ +} + +CMP128(<) +CMP128(>) +CMP128(>=) +CMP128(<=) + +#undef CMP128 + +// Unary operators + +inline uint128 operator-(const uint128& val) { + const uint64 hi_flip = ~Uint128High64(val); + const uint64 lo_flip = ~Uint128Low64(val); + const uint64 lo_add = lo_flip + 1; + if (lo_add < lo_flip) { + return uint128(hi_flip + 1, lo_add); + } + return uint128(hi_flip, lo_add); +} + +inline bool operator!(const uint128& val) { + return !Uint128High64(val) && !Uint128Low64(val); +} + +// Logical operators. + +inline uint128 operator~(const uint128& val) { + return uint128(~Uint128High64(val), ~Uint128Low64(val)); +} + +#define LOGIC128(op) \ +inline uint128 operator op(const uint128& lhs, const uint128& rhs) { \ + return uint128(Uint128High64(lhs) op Uint128High64(rhs), \ + Uint128Low64(lhs) op Uint128Low64(rhs)); \ +} + +LOGIC128(|) +LOGIC128(&) +LOGIC128(^) + +#undef LOGIC128 + +#define LOGICASSIGN128(op) \ +inline uint128& uint128::operator op(const uint128& other) { \ + hi_ op other.hi_; \ + lo_ op other.lo_; \ + return *this; \ +} + +LOGICASSIGN128(|=) +LOGICASSIGN128(&=) +LOGICASSIGN128(^=) + +#undef LOGICASSIGN128 + +// Shift operators. + +inline uint128 operator<<(const uint128& val, int amount) { + // uint64 shifts of >= 64 are undefined, so we will need some special-casing. + if (amount < 64) { + if (amount == 0) { + return val; + } + uint64 new_hi = (Uint128High64(val) << amount) | + (Uint128Low64(val) >> (64 - amount)); + uint64 new_lo = Uint128Low64(val) << amount; + return uint128(new_hi, new_lo); + } else if (amount < 128) { + return uint128(Uint128Low64(val) << (amount - 64), 0); + } else { + return uint128(0, 0); + } +} + +inline uint128 operator>>(const uint128& val, int amount) { + // uint64 shifts of >= 64 are undefined, so we will need some special-casing. + if (amount < 64) { + if (amount == 0) { + return val; + } + uint64 new_hi = Uint128High64(val) >> amount; + uint64 new_lo = (Uint128Low64(val) >> amount) | + (Uint128High64(val) << (64 - amount)); + return uint128(new_hi, new_lo); + } else if (amount < 128) { + return uint128(0, Uint128High64(val) >> (amount - 64)); + } else { + return uint128(0, 0); + } +} + +inline uint128& uint128::operator<<=(int amount) { + // uint64 shifts of >= 64 are undefined, so we will need some special-casing. + if (amount < 64) { + if (amount != 0) { + hi_ = (hi_ << amount) | (lo_ >> (64 - amount)); + lo_ = lo_ << amount; + } + } else if (amount < 128) { + hi_ = lo_ << (amount - 64); + lo_ = 0; + } else { + hi_ = 0; + lo_ = 0; + } + return *this; +} + +inline uint128& uint128::operator>>=(int amount) { + // uint64 shifts of >= 64 are undefined, so we will need some special-casing. + if (amount < 64) { + if (amount != 0) { + lo_ = (lo_ >> amount) | (hi_ << (64 - amount)); + hi_ = hi_ >> amount; + } + } else if (amount < 128) { + hi_ = 0; + lo_ = hi_ >> (amount - 64); + } else { + hi_ = 0; + lo_ = 0; + } + return *this; +} + +inline uint128 operator+(const uint128& lhs, const uint128& rhs) { + return uint128(lhs) += rhs; +} + +inline uint128 operator-(const uint128& lhs, const uint128& rhs) { + return uint128(lhs) -= rhs; +} + +inline uint128 operator*(const uint128& lhs, const uint128& rhs) { + return uint128(lhs) *= rhs; +} + +inline uint128& uint128::operator+=(const uint128& b) { + hi_ += b.hi_; + uint64 lolo = lo_ + b.lo_; + if (lolo < lo_) + ++hi_; + lo_ = lolo; + return *this; +} + +inline uint128& uint128::operator-=(const uint128& b) { + hi_ -= b.hi_; + if (b.lo_ > lo_) + --hi_; + lo_ -= b.lo_; + return *this; +} + +inline uint128& uint128::operator*=(const uint128& b) { + uint64 a96 = hi_ >> 32; + uint64 a64 = hi_ & 0xffffffffu; + uint64 a32 = lo_ >> 32; + uint64 a00 = lo_ & 0xffffffffu; + uint64 b96 = b.hi_ >> 32; + uint64 b64 = b.hi_ & 0xffffffffu; + uint64 b32 = b.lo_ >> 32; + uint64 b00 = b.lo_ & 0xffffffffu; + // multiply [a96 .. a00] x [b96 .. b00] + // terms higher than c96 disappear off the high side + // terms c96 and c64 are safe to ignore carry bit + uint64 c96 = a96 * b00 + a64 * b32 + a32 * b64 + a00 * b96; + uint64 c64 = a64 * b00 + a32 * b32 + a00 * b64; + this->hi_ = (c96 << 32) + c64; + this->lo_ = 0; + // add terms after this one at a time to capture carry + *this += uint128(a32 * b00) << 32; + *this += uint128(a00 * b32) << 32; + *this += a00 * b00; + return *this; +} + +inline uint128 uint128::operator++(int) { + uint128 tmp(*this); + *this += 1; + return tmp; +} + +inline uint128 uint128::operator--(int) { + uint128 tmp(*this); + *this -= 1; + return tmp; +} + +inline uint128& uint128::operator++() { + *this += 1; + return *this; +} + +inline uint128& uint128::operator--() { + *this -= 1; + return *this; +} + +#endif // NET_BASE_INT128_H_ diff --git a/net/base/int128_unittest.cc b/net/base/int128_unittest.cc new file mode 100644 index 0000000..78790e7 --- /dev/null +++ b/net/base/int128_unittest.cc @@ -0,0 +1,265 @@ +// 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 "base/basictypes.h" +#include "base/logging.h" +#include "net/base/int128.h" +#include "testing/gtest/include/gtest/gtest.h" + + +TEST(Int128, AllTests) { + uint128 zero(0); + uint128 one(1); + uint128 one_2arg(0, 1); + uint128 two(0, 2); + uint128 three(0, 3); + uint128 big(2000, 2); + uint128 big_minus_one(2000, 1); + uint128 bigger(2001, 1); + uint128 biggest(kuint128max); + uint128 high_low(1, 0); + uint128 low_high(0, kuint64max); + EXPECT_LT(one, two); + EXPECT_GT(two, one); + EXPECT_LT(one, big); + EXPECT_LT(one, big); + EXPECT_EQ(one, one_2arg); + EXPECT_NE(one, two); + EXPECT_GT(big, one); + EXPECT_GE(big, two); + EXPECT_GE(big, big_minus_one); + EXPECT_GT(big, big_minus_one); + EXPECT_LT(big_minus_one, big); + EXPECT_LE(big_minus_one, big); + EXPECT_NE(big_minus_one, big); + EXPECT_LT(big, biggest); + EXPECT_LE(big, biggest); + EXPECT_GT(biggest, big); + EXPECT_GE(biggest, big); + EXPECT_EQ(big, ~~big); + EXPECT_EQ(one, one | one); + EXPECT_EQ(big, big | big); + EXPECT_EQ(one, one | zero); + EXPECT_EQ(one, one & one); + EXPECT_EQ(big, big & big); + EXPECT_EQ(zero, one & zero); + EXPECT_EQ(zero, big & ~big); + EXPECT_EQ(zero, one ^ one); + EXPECT_EQ(zero, big ^ big); + EXPECT_EQ(one, one ^ zero); + EXPECT_EQ(big, big << 0); + EXPECT_EQ(big, big >> 0); + EXPECT_GT(big << 1, big); + EXPECT_LT(big >> 1, big); + EXPECT_EQ(big, (big << 10) >> 10); + EXPECT_EQ(big, (big >> 1) << 1); + EXPECT_EQ(one, (one << 80) >> 80); + EXPECT_EQ(zero, (one >> 80) << 80); + EXPECT_EQ(zero, big >> 128); + EXPECT_EQ(zero, big << 128); + EXPECT_EQ(Uint128High64(biggest), kuint64max); + EXPECT_EQ(Uint128Low64(biggest), kuint64max); + EXPECT_EQ(zero + one, one); + EXPECT_EQ(one + one, two); + EXPECT_EQ(big_minus_one + one, big); + EXPECT_EQ(one - one, zero); + EXPECT_EQ(one - zero, one); + EXPECT_EQ(zero - one, biggest); + EXPECT_EQ(big - big, zero); + EXPECT_EQ(big - one, big_minus_one); + EXPECT_EQ(big + kuint64max, bigger); + EXPECT_EQ(biggest + 1, zero); + EXPECT_EQ(zero - 1, biggest); + EXPECT_EQ(high_low - one, low_high); + EXPECT_EQ(low_high + one, high_low); + EXPECT_EQ(Uint128High64((uint128(1) << 64) - 1), 0u); + EXPECT_EQ(Uint128Low64((uint128(1) << 64) - 1), kuint64max); + EXPECT_TRUE(!!one); + EXPECT_TRUE(!!high_low); + EXPECT_FALSE(!!zero); + EXPECT_FALSE(!one); + EXPECT_FALSE(!high_low); + EXPECT_TRUE(!zero); + EXPECT_TRUE(zero == 0); + EXPECT_FALSE(zero != 0); + EXPECT_FALSE(one == 0); + EXPECT_TRUE(one != 0); + + uint128 test = zero; + EXPECT_EQ(++test, one); + EXPECT_EQ(test, one); + EXPECT_EQ(test++, one); + EXPECT_EQ(test, two); + EXPECT_EQ(test -= 2, zero); + EXPECT_EQ(test, zero); + EXPECT_EQ(test += 2, two); + EXPECT_EQ(test, two); + EXPECT_EQ(--test, one); + EXPECT_EQ(test, one); + EXPECT_EQ(test--, one); + EXPECT_EQ(test, zero); + EXPECT_EQ(test |= three, three); + EXPECT_EQ(test &= one, one); + EXPECT_EQ(test ^= three, two); + EXPECT_EQ(test >>= 1, one); + EXPECT_EQ(test <<= 1, two); + + EXPECT_EQ(big, -(-big)); + EXPECT_EQ(two, -((-one) - 1)); + EXPECT_EQ(kuint128max, -one); + EXPECT_EQ(zero, -zero); + + LOG(INFO) << one; + LOG(INFO) << big_minus_one; +} + +TEST(Int128, PodTests) { + uint128_pod pod = { 12345, 67890 }; + uint128 from_pod(pod); + EXPECT_EQ(12345u, Uint128High64(from_pod)); + EXPECT_EQ(67890u, Uint128Low64(from_pod)); + + uint128 zero(0); + uint128_pod zero_pod = {0, 0}; + uint128 one(1); + uint128_pod one_pod = {0, 1}; + uint128 two(2); + uint128_pod two_pod = {0, 2}; + uint128 three(3); + uint128_pod three_pod = {0, 3}; + uint128 big(1, 0); + uint128_pod big_pod = {1, 0}; + + EXPECT_EQ(zero, zero_pod); + EXPECT_EQ(zero_pod, zero); + EXPECT_EQ(zero_pod, zero_pod); + EXPECT_EQ(one, one_pod); + EXPECT_EQ(one_pod, one); + EXPECT_EQ(one_pod, one_pod); + EXPECT_EQ(two, two_pod); + EXPECT_EQ(two_pod, two); + EXPECT_EQ(two_pod, two_pod); + + EXPECT_NE(one, two_pod); + EXPECT_NE(one_pod, two); + EXPECT_NE(one_pod, two_pod); + + EXPECT_LT(one, two_pod); + EXPECT_LT(one_pod, two); + EXPECT_LT(one_pod, two_pod); + EXPECT_LE(one, one_pod); + EXPECT_LE(one_pod, one); + EXPECT_LE(one_pod, one_pod); + EXPECT_LE(one, two_pod); + EXPECT_LE(one_pod, two); + EXPECT_LE(one_pod, two_pod); + + EXPECT_GT(two, one_pod); + EXPECT_GT(two_pod, one); + EXPECT_GT(two_pod, one_pod); + EXPECT_GE(two, two_pod); + EXPECT_GE(two_pod, two); + EXPECT_GE(two_pod, two_pod); + EXPECT_GE(two, one_pod); + EXPECT_GE(two_pod, one); + EXPECT_GE(two_pod, one_pod); + + EXPECT_EQ(three, one | two_pod); + EXPECT_EQ(three, one_pod | two); + EXPECT_EQ(three, one_pod | two_pod); + EXPECT_EQ(one, three & one_pod); + EXPECT_EQ(one, three_pod & one); + EXPECT_EQ(one, three_pod & one_pod); + EXPECT_EQ(two, three ^ one_pod); + EXPECT_EQ(two, three_pod ^ one); + EXPECT_EQ(two, three_pod ^ one_pod); + EXPECT_EQ(two, three & (~one)); + EXPECT_EQ(three, ~~three); + + EXPECT_EQ(two, two_pod << 0); + EXPECT_EQ(two, one_pod << 1); + EXPECT_EQ(big, one_pod << 64); + EXPECT_EQ(zero, one_pod << 128); + EXPECT_EQ(two, two_pod >> 0); + EXPECT_EQ(one, two_pod >> 1); + EXPECT_EQ(one, big_pod >> 64); + + EXPECT_EQ(one, zero + one_pod); + EXPECT_EQ(one, zero_pod + one); + EXPECT_EQ(one, zero_pod + one_pod); + EXPECT_EQ(one, two - one_pod); + EXPECT_EQ(one, two_pod - one); + EXPECT_EQ(one, two_pod - one_pod); +} + +TEST(Int128, OperatorAssignReturnRef) { + uint128 v(1); + (v += 4) -= 3; + EXPECT_EQ(2, v); +} + +TEST(Int128, Multiply) { + uint128 a, b, c; + + // Zero test. + a = 0; + b = 0; + c = a * b; + EXPECT_EQ(0, c); + + // Max carries. + a = uint128(0) - 1; + b = uint128(0) - 1; + c = a * b; + EXPECT_EQ(1, c); + + // Self-operation with max carries. + c = uint128(0) - 1; + c *= c; + EXPECT_EQ(1, c); + + // 1-bit x 1-bit. + for (int i = 0; i < 64; ++i) { + for (int j = 0; j < 64; ++j) { + a = uint128(1) << i; + b = uint128(1) << j; + c = a * b; + EXPECT_EQ(uint128(1) << (i+j), c); + } + } + + // Verified with dc. + a = uint128(GG_ULONGLONG(0xffffeeeeddddcccc), + GG_ULONGLONG(0xbbbbaaaa99998888)); + b = uint128(GG_ULONGLONG(0x7777666655554444), + GG_ULONGLONG(0x3333222211110000)); + c = a * b; + EXPECT_EQ(uint128(GG_ULONGLONG(0x530EDA741C71D4C3), + GG_ULONGLONG(0xBF25975319080000)), c); + EXPECT_EQ(0, c - b * a); + EXPECT_EQ(a*a - b*b, (a+b) * (a-b)); + + // Verified with dc. + a = uint128(GG_ULONGLONG(0x0123456789abcdef), + GG_ULONGLONG(0xfedcba9876543210)); + b = uint128(GG_ULONGLONG(0x02468ace13579bdf), + GG_ULONGLONG(0xfdb97531eca86420)); + c = a * b; + EXPECT_EQ(uint128(GG_ULONGLONG(0x97a87f4f261ba3f2), + GG_ULONGLONG(0x342d0bbf48948200)), c); + EXPECT_EQ(0, c - b * a); + EXPECT_EQ(a*a - b*b, (a+b) * (a-b)); +} + +TEST(Int128, AliasTests) { + uint128 x1(1, 2); + uint128 x2(2, 4); + x1 += x1; + EXPECT_EQ(x2, x1); + + uint128 x3(1, 1ull << 63); + uint128 x4(3, 0); + x3 += x3; + EXPECT_EQ(x4, x3); +} |