llvm/unittests/Support/ScaledNumberTest.cpp
2014-06-20 21:47:47 +00:00

195 lines
7.1 KiB
C++

//===- llvm/unittest/Support/ScaledNumberTest.cpp - ScaledPair tests -----==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/ScaledNumber.h"
#include "llvm/Support/DataTypes.h"
#include "gtest/gtest.h"
using namespace llvm;
using namespace llvm::ScaledNumbers;
namespace {
template <class UIntT> struct ScaledPair {
UIntT D;
int S;
ScaledPair(const std::pair<UIntT, int16_t> &F) : D(F.first), S(F.second) {}
ScaledPair(UIntT D, int S) : D(D), S(S) {}
bool operator==(const ScaledPair<UIntT> &X) const {
return D == X.D && S == X.S;
}
};
template <class UIntT>
bool operator==(const std::pair<UIntT, int16_t> &L,
const ScaledPair<UIntT> &R) {
return ScaledPair<UIntT>(L) == R;
}
template <class UIntT>
void PrintTo(const ScaledPair<UIntT> &F, ::std::ostream *os) {
*os << F.D << "*2^" << F.S;
}
typedef ScaledPair<uint32_t> SP32;
typedef ScaledPair<uint64_t> SP64;
TEST(ScaledNumberHelpersTest, getRounded) {
EXPECT_EQ(getRounded32(0, 0, false), SP32(0, 0));
EXPECT_EQ(getRounded32(0, 0, true), SP32(1, 0));
EXPECT_EQ(getRounded32(20, 21, true), SP32(21, 21));
EXPECT_EQ(getRounded32(UINT32_MAX, 0, false), SP32(UINT32_MAX, 0));
EXPECT_EQ(getRounded32(UINT32_MAX, 0, true), SP32(1 << 31, 1));
EXPECT_EQ(getRounded64(0, 0, false), SP64(0, 0));
EXPECT_EQ(getRounded64(0, 0, true), SP64(1, 0));
EXPECT_EQ(getRounded64(20, 21, true), SP64(21, 21));
EXPECT_EQ(getRounded64(UINT32_MAX, 0, false), SP64(UINT32_MAX, 0));
EXPECT_EQ(getRounded64(UINT32_MAX, 0, true), SP64(UINT64_C(1) << 32, 0));
EXPECT_EQ(getRounded64(UINT64_MAX, 0, false), SP64(UINT64_MAX, 0));
EXPECT_EQ(getRounded64(UINT64_MAX, 0, true), SP64(UINT64_C(1) << 63, 1));
}
TEST(FloatsTest, getAdjusted) {
const uint64_t Max32In64 = UINT32_MAX;
EXPECT_EQ(getAdjusted32(0), SP32(0, 0));
EXPECT_EQ(getAdjusted32(0, 5), SP32(0, 5));
EXPECT_EQ(getAdjusted32(UINT32_MAX), SP32(UINT32_MAX, 0));
EXPECT_EQ(getAdjusted32(Max32In64 << 1), SP32(UINT32_MAX, 1));
EXPECT_EQ(getAdjusted32(Max32In64 << 1, 1), SP32(UINT32_MAX, 2));
EXPECT_EQ(getAdjusted32(Max32In64 << 31), SP32(UINT32_MAX, 31));
EXPECT_EQ(getAdjusted32(Max32In64 << 32), SP32(UINT32_MAX, 32));
EXPECT_EQ(getAdjusted32(Max32In64 + 1), SP32(1u << 31, 1));
EXPECT_EQ(getAdjusted32(UINT64_MAX), SP32(1u << 31, 33));
EXPECT_EQ(getAdjusted64(0), SP64(0, 0));
EXPECT_EQ(getAdjusted64(0, 5), SP64(0, 5));
EXPECT_EQ(getAdjusted64(UINT32_MAX), SP64(UINT32_MAX, 0));
EXPECT_EQ(getAdjusted64(Max32In64 << 1), SP64(Max32In64 << 1, 0));
EXPECT_EQ(getAdjusted64(Max32In64 << 1, 1), SP64(Max32In64 << 1, 1));
EXPECT_EQ(getAdjusted64(Max32In64 << 31), SP64(Max32In64 << 31, 0));
EXPECT_EQ(getAdjusted64(Max32In64 << 32), SP64(Max32In64 << 32, 0));
EXPECT_EQ(getAdjusted64(Max32In64 + 1), SP64(Max32In64 + 1, 0));
EXPECT_EQ(getAdjusted64(UINT64_MAX), SP64(UINT64_MAX, 0));
}
TEST(PositiveFloatTest, getProduct) {
// Zero.
EXPECT_EQ(SP32(0, 0), getProduct32(0, 0));
EXPECT_EQ(SP32(0, 0), getProduct32(0, 1));
EXPECT_EQ(SP32(0, 0), getProduct32(0, 33));
// Basic.
EXPECT_EQ(SP32(6, 0), getProduct32(2, 3));
EXPECT_EQ(SP32(UINT16_MAX / 3 * UINT16_MAX / 5 * 2, 0),
getProduct32(UINT16_MAX / 3, UINT16_MAX / 5 * 2));
// Overflow, no loss of precision.
// ==> 0xf00010 * 0x1001
// ==> 0xf00f00000 + 0x10010
// ==> 0xf00f10010
// ==> 0xf00f1001 * 2^4
EXPECT_EQ(SP32(0xf00f1001, 4), getProduct32(0xf00010, 0x1001));
// Overflow, loss of precision, rounds down.
// ==> 0xf000070 * 0x1001
// ==> 0xf00f000000 + 0x70070
// ==> 0xf00f070070
// ==> 0xf00f0700 * 2^8
EXPECT_EQ(SP32(0xf00f0700, 8), getProduct32(0xf000070, 0x1001));
// Overflow, loss of precision, rounds up.
// ==> 0xf000080 * 0x1001
// ==> 0xf00f000000 + 0x80080
// ==> 0xf00f080080
// ==> 0xf00f0801 * 2^8
EXPECT_EQ(SP32(0xf00f0801, 8), getProduct32(0xf000080, 0x1001));
// Reverse operand order.
EXPECT_EQ(SP32(0, 0), getProduct32(1, 0));
EXPECT_EQ(SP32(0, 0), getProduct32(33, 0));
EXPECT_EQ(SP32(6, 0), getProduct32(3, 2));
EXPECT_EQ(SP32(UINT16_MAX / 3 * UINT16_MAX / 5 * 2, 0),
getProduct32(UINT16_MAX / 5 * 2, UINT16_MAX / 3));
EXPECT_EQ(SP32(0xf00f1001, 4), getProduct32(0x1001, 0xf00010));
EXPECT_EQ(SP32(0xf00f0700, 8), getProduct32(0x1001, 0xf000070));
EXPECT_EQ(SP32(0xf00f0801, 8), getProduct32(0x1001, 0xf000080));
// Round to overflow.
EXPECT_EQ(SP64(UINT64_C(1) << 63, 64),
getProduct64(UINT64_C(10376293541461622786),
UINT64_C(16397105843297379211)));
// Big number with rounding.
EXPECT_EQ(SP64(UINT64_C(9223372036854775810), 64),
getProduct64(UINT64_C(18446744073709551556),
UINT64_C(9223372036854775840)));
}
TEST(PositiveFloatTest, Divide) {
// Zero.
EXPECT_EQ(SP32(0, 0), getQuotient32(0, 0));
EXPECT_EQ(SP32(0, 0), getQuotient32(0, 1));
EXPECT_EQ(SP32(0, 0), getQuotient32(0, 73));
EXPECT_EQ(SP32(UINT32_MAX, INT16_MAX), getQuotient32(1, 0));
EXPECT_EQ(SP32(UINT32_MAX, INT16_MAX), getQuotient32(6, 0));
// Powers of two.
EXPECT_EQ(SP32(1u << 31, -31), getQuotient32(1, 1));
EXPECT_EQ(SP32(1u << 31, -30), getQuotient32(2, 1));
EXPECT_EQ(SP32(1u << 31, -33), getQuotient32(4, 16));
EXPECT_EQ(SP32(7u << 29, -29), getQuotient32(7, 1));
EXPECT_EQ(SP32(7u << 29, -30), getQuotient32(7, 2));
EXPECT_EQ(SP32(7u << 29, -33), getQuotient32(7, 16));
// Divide evenly.
EXPECT_EQ(SP32(3u << 30, -30), getQuotient32(9, 3));
EXPECT_EQ(SP32(9u << 28, -28), getQuotient32(63, 7));
// Divide unevenly.
EXPECT_EQ(SP32(0xaaaaaaab, -33), getQuotient32(1, 3));
EXPECT_EQ(SP32(0xd5555555, -31), getQuotient32(5, 3));
// 64-bit division is hard to test, since divide64 doesn't canonicalized its
// output. However, this is the algorithm the implementation uses:
//
// - Shift divisor right.
// - If we have 1 (power of 2), return early -- not canonicalized.
// - Shift dividend left.
// - 64-bit integer divide.
// - If there's a remainder, continue with long division.
//
// TODO: require less knowledge about the implementation in the test.
// Zero.
EXPECT_EQ(SP64(0, 0), getQuotient64(0, 0));
EXPECT_EQ(SP64(0, 0), getQuotient64(0, 1));
EXPECT_EQ(SP64(0, 0), getQuotient64(0, 73));
EXPECT_EQ(SP64(UINT64_MAX, INT16_MAX), getQuotient64(1, 0));
EXPECT_EQ(SP64(UINT64_MAX, INT16_MAX), getQuotient64(6, 0));
// Powers of two.
EXPECT_EQ(SP64(1, 0), getQuotient64(1, 1));
EXPECT_EQ(SP64(2, 0), getQuotient64(2, 1));
EXPECT_EQ(SP64(4, -4), getQuotient64(4, 16));
EXPECT_EQ(SP64(7, 0), getQuotient64(7, 1));
EXPECT_EQ(SP64(7, -1), getQuotient64(7, 2));
EXPECT_EQ(SP64(7, -4), getQuotient64(7, 16));
// Divide evenly.
EXPECT_EQ(SP64(UINT64_C(3) << 60, -60), getQuotient64(9, 3));
EXPECT_EQ(SP64(UINT64_C(9) << 58, -58), getQuotient64(63, 7));
// Divide unevenly.
EXPECT_EQ(SP64(0xaaaaaaaaaaaaaaab, -65), getQuotient64(1, 3));
EXPECT_EQ(SP64(0xd555555555555555, -63), getQuotient64(5, 3));
}
} // end namespace