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Edit File: test-double.cc
// Copyright 2006-2008 the V8 project authors. All rights reserved. #include <stdlib.h> #include "v8.h" #include "platform.h" #include "cctest.h" #include "diy-fp.h" #include "double.h" using namespace v8::internal; TEST(Uint64Conversions) { // Start by checking the byte-order. uint64_t ordered = V8_2PART_UINT64_C(0x01234567, 89ABCDEF); CHECK_EQ(3512700564088504e-318, Double(ordered).value()); uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001); CHECK_EQ(5e-324, Double(min_double64).value()); uint64_t max_double64 = V8_2PART_UINT64_C(0x7fefffff, ffffffff); CHECK_EQ(1.7976931348623157e308, Double(max_double64).value()); } TEST(AsDiyFp) { uint64_t ordered = V8_2PART_UINT64_C(0x01234567, 89ABCDEF); DiyFp diy_fp = Double(ordered).AsDiyFp(); CHECK_EQ(0x12 - 0x3FF - 52, diy_fp.e()); // The 52 mantissa bits, plus the implicit 1 in bit 52 as a UINT64. CHECK(V8_2PART_UINT64_C(0x00134567, 89ABCDEF) == diy_fp.f()); // NOLINT uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001); diy_fp = Double(min_double64).AsDiyFp(); CHECK_EQ(-0x3FF - 52 + 1, diy_fp.e()); // This is a denormal; so no hidden bit. CHECK(1 == diy_fp.f()); // NOLINT uint64_t max_double64 = V8_2PART_UINT64_C(0x7fefffff, ffffffff); diy_fp = Double(max_double64).AsDiyFp(); CHECK_EQ(0x7FE - 0x3FF - 52, diy_fp.e()); CHECK(V8_2PART_UINT64_C(0x001fffff, ffffffff) == diy_fp.f()); // NOLINT } TEST(AsNormalizedDiyFp) { uint64_t ordered = V8_2PART_UINT64_C(0x01234567, 89ABCDEF); DiyFp diy_fp = Double(ordered).AsNormalizedDiyFp(); CHECK_EQ(0x12 - 0x3FF - 52 - 11, diy_fp.e()); CHECK((V8_2PART_UINT64_C(0x00134567, 89ABCDEF) << 11) == diy_fp.f()); // NOLINT uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001); diy_fp = Double(min_double64).AsNormalizedDiyFp(); CHECK_EQ(-0x3FF - 52 + 1 - 63, diy_fp.e()); // This is a denormal; so no hidden bit. CHECK(V8_2PART_UINT64_C(0x80000000, 00000000) == diy_fp.f()); // NOLINT uint64_t max_double64 = V8_2PART_UINT64_C(0x7fefffff, ffffffff); diy_fp = Double(max_double64).AsNormalizedDiyFp(); CHECK_EQ(0x7FE - 0x3FF - 52 - 11, diy_fp.e()); CHECK((V8_2PART_UINT64_C(0x001fffff, ffffffff) << 11) == diy_fp.f()); // NOLINT } TEST(IsDenormal) { uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001); CHECK(Double(min_double64).IsDenormal()); uint64_t bits = V8_2PART_UINT64_C(0x000FFFFF, FFFFFFFF); CHECK(Double(bits).IsDenormal()); bits = V8_2PART_UINT64_C(0x00100000, 00000000); CHECK(!Double(bits).IsDenormal()); } TEST(IsSpecial) { CHECK(Double(V8_INFINITY).IsSpecial()); CHECK(Double(-V8_INFINITY).IsSpecial()); CHECK(Double(OS::nan_value()).IsSpecial()); uint64_t bits = V8_2PART_UINT64_C(0xFFF12345, 00000000); CHECK(Double(bits).IsSpecial()); // Denormals are not special: CHECK(!Double(5e-324).IsSpecial()); CHECK(!Double(-5e-324).IsSpecial()); // And some random numbers: CHECK(!Double(0.0).IsSpecial()); CHECK(!Double(-0.0).IsSpecial()); CHECK(!Double(1.0).IsSpecial()); CHECK(!Double(-1.0).IsSpecial()); CHECK(!Double(1000000.0).IsSpecial()); CHECK(!Double(-1000000.0).IsSpecial()); CHECK(!Double(1e23).IsSpecial()); CHECK(!Double(-1e23).IsSpecial()); CHECK(!Double(1.7976931348623157e308).IsSpecial()); CHECK(!Double(-1.7976931348623157e308).IsSpecial()); } TEST(IsInfinite) { CHECK(Double(V8_INFINITY).IsInfinite()); CHECK(Double(-V8_INFINITY).IsInfinite()); CHECK(!Double(OS::nan_value()).IsInfinite()); CHECK(!Double(0.0).IsInfinite()); CHECK(!Double(-0.0).IsInfinite()); CHECK(!Double(1.0).IsInfinite()); CHECK(!Double(-1.0).IsInfinite()); uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001); CHECK(!Double(min_double64).IsInfinite()); } TEST(Sign) { CHECK_EQ(1, Double(1.0).Sign()); CHECK_EQ(1, Double(V8_INFINITY).Sign()); CHECK_EQ(-1, Double(-V8_INFINITY).Sign()); CHECK_EQ(1, Double(0.0).Sign()); CHECK_EQ(-1, Double(-0.0).Sign()); uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001); CHECK_EQ(1, Double(min_double64).Sign()); } TEST(NormalizedBoundaries) { DiyFp boundary_plus; DiyFp boundary_minus; DiyFp diy_fp = Double(1.5).AsNormalizedDiyFp(); Double(1.5).NormalizedBoundaries(&boundary_minus, &boundary_plus); CHECK_EQ(diy_fp.e(), boundary_minus.e()); CHECK_EQ(diy_fp.e(), boundary_plus.e()); // 1.5 does not have a significand of the form 2^p (for some p). // Therefore its boundaries are at the same distance. CHECK(diy_fp.f() - boundary_minus.f() == boundary_plus.f() - diy_fp.f()); CHECK((1 << 10) == diy_fp.f() - boundary_minus.f()); // NOLINT diy_fp = Double(1.0).AsNormalizedDiyFp(); Double(1.0).NormalizedBoundaries(&boundary_minus, &boundary_plus); CHECK_EQ(diy_fp.e(), boundary_minus.e()); CHECK_EQ(diy_fp.e(), boundary_plus.e()); // 1.0 does have a significand of the form 2^p (for some p). // Therefore its lower boundary is twice as close as the upper boundary. CHECK_GT(boundary_plus.f() - diy_fp.f(), diy_fp.f() - boundary_minus.f()); CHECK((1 << 9) == diy_fp.f() - boundary_minus.f()); // NOLINT CHECK((1 << 10) == boundary_plus.f() - diy_fp.f()); // NOLINT uint64_t min_double64 = V8_2PART_UINT64_C(0x00000000, 00000001); diy_fp = Double(min_double64).AsNormalizedDiyFp(); Double(min_double64).NormalizedBoundaries(&boundary_minus, &boundary_plus); CHECK_EQ(diy_fp.e(), boundary_minus.e()); CHECK_EQ(diy_fp.e(), boundary_plus.e()); // min-value does not have a significand of the form 2^p (for some p). // Therefore its boundaries are at the same distance. CHECK(diy_fp.f() - boundary_minus.f() == boundary_plus.f() - diy_fp.f()); // Denormals have their boundaries much closer. CHECK((static_cast<uint64_t>(1) << 62) == diy_fp.f() - boundary_minus.f()); // NOLINT uint64_t smallest_normal64 = V8_2PART_UINT64_C(0x00100000, 00000000); diy_fp = Double(smallest_normal64).AsNormalizedDiyFp(); Double(smallest_normal64).NormalizedBoundaries(&boundary_minus, &boundary_plus); CHECK_EQ(diy_fp.e(), boundary_minus.e()); CHECK_EQ(diy_fp.e(), boundary_plus.e()); // Even though the significand is of the form 2^p (for some p), its boundaries // are at the same distance. (This is the only exception). CHECK(diy_fp.f() - boundary_minus.f() == boundary_plus.f() - diy_fp.f()); CHECK((1 << 10) == diy_fp.f() - boundary_minus.f()); // NOLINT uint64_t largest_denormal64 = V8_2PART_UINT64_C(0x000FFFFF, FFFFFFFF); diy_fp = Double(largest_denormal64).AsNormalizedDiyFp(); Double(largest_denormal64).NormalizedBoundaries(&boundary_minus, &boundary_plus); CHECK_EQ(diy_fp.e(), boundary_minus.e()); CHECK_EQ(diy_fp.e(), boundary_plus.e()); CHECK(diy_fp.f() - boundary_minus.f() == boundary_plus.f() - diy_fp.f()); CHECK((1 << 11) == diy_fp.f() - boundary_minus.f()); // NOLINT uint64_t max_double64 = V8_2PART_UINT64_C(0x7fefffff, ffffffff); diy_fp = Double(max_double64).AsNormalizedDiyFp(); Double(max_double64).NormalizedBoundaries(&boundary_minus, &boundary_plus); CHECK_EQ(diy_fp.e(), boundary_minus.e()); CHECK_EQ(diy_fp.e(), boundary_plus.e()); // max-value does not have a significand of the form 2^p (for some p). // Therefore its boundaries are at the same distance. CHECK(diy_fp.f() - boundary_minus.f() == boundary_plus.f() - diy_fp.f()); CHECK((1 << 10) == diy_fp.f() - boundary_minus.f()); // NOLINT } TEST(NextDouble) { CHECK_EQ(4e-324, Double(0.0).NextDouble()); CHECK_EQ(0.0, Double(-0.0).NextDouble()); CHECK_EQ(-0.0, Double(-4e-324).NextDouble()); Double d0(-4e-324); Double d1(d0.NextDouble()); Double d2(d1.NextDouble()); CHECK_EQ(-0.0, d1.value()); CHECK_EQ(0.0, d2.value()); CHECK_EQ(4e-324, d2.NextDouble()); CHECK_EQ(-1.7976931348623157e308, Double(-V8_INFINITY).NextDouble()); CHECK_EQ(V8_INFINITY, Double(V8_2PART_UINT64_C(0x7fefffff, ffffffff)).NextDouble()); }