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-rw-r--r--src/Makefile.test.include1
-rw-r--r--src/test/serfloat_tests.cpp92
2 files changed, 93 insertions, 0 deletions
diff --git a/src/Makefile.test.include b/src/Makefile.test.include
index dc79ea3125..e5f9c4cb52 100644
--- a/src/Makefile.test.include
+++ b/src/Makefile.test.include
@@ -121,6 +121,7 @@ BITCOIN_TESTS =\
test/script_tests.cpp \
test/script_standard_tests.cpp \
test/scriptnum_tests.cpp \
+ test/serfloat_tests.cpp \
test/serialize_tests.cpp \
test/settings_tests.cpp \
test/sighash_tests.cpp \
diff --git a/src/test/serfloat_tests.cpp b/src/test/serfloat_tests.cpp
new file mode 100644
index 0000000000..5b49488c5d
--- /dev/null
+++ b/src/test/serfloat_tests.cpp
@@ -0,0 +1,92 @@
+// Copyright (c) 2014-2020 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <test/util/setup_common.h>
+#include <util/serfloat.h>
+
+#include <boost/test/unit_test.hpp>
+
+#include <cmath>
+#include <limits>
+
+BOOST_FIXTURE_TEST_SUITE(serfloat_tests, BasicTestingSetup)
+
+namespace {
+
+uint64_t TestDouble(double f) {
+ uint64_t i = EncodeDouble(f);
+ double f2 = DecodeDouble(i);
+ if (std::isnan(f)) {
+ // NaN is not guaranteed to round-trip exactly.
+ BOOST_CHECK(std::isnan(f2));
+ } else {
+ // Everything else is.
+ BOOST_CHECK(!std::isnan(f2));
+ uint64_t i2 = EncodeDouble(f2);
+ BOOST_CHECK_EQUAL(f, f2);
+ BOOST_CHECK_EQUAL(i, i2);
+ }
+ return i;
+}
+
+} // namespace
+
+BOOST_AUTO_TEST_CASE(double_serfloat_tests) {
+ BOOST_CHECK_EQUAL(TestDouble(0.0), 0);
+ BOOST_CHECK_EQUAL(TestDouble(-0.0), 0x8000000000000000);
+ BOOST_CHECK_EQUAL(TestDouble(std::numeric_limits<double>::infinity()), 0x7ff0000000000000);
+ BOOST_CHECK_EQUAL(TestDouble(-std::numeric_limits<double>::infinity()), 0xfff0000000000000);
+
+ if (std::numeric_limits<float>::is_iec559) {
+ BOOST_CHECK_EQUAL(sizeof(double), 8);
+ BOOST_CHECK_EQUAL(sizeof(uint64_t), 8);
+ // Test extreme values
+ TestDouble(std::numeric_limits<double>::min());
+ TestDouble(-std::numeric_limits<double>::min());
+ TestDouble(std::numeric_limits<double>::max());
+ TestDouble(-std::numeric_limits<double>::max());
+ TestDouble(std::numeric_limits<double>::lowest());
+ TestDouble(-std::numeric_limits<double>::lowest());
+ TestDouble(std::numeric_limits<double>::quiet_NaN());
+ TestDouble(-std::numeric_limits<double>::quiet_NaN());
+ TestDouble(std::numeric_limits<double>::signaling_NaN());
+ TestDouble(-std::numeric_limits<double>::signaling_NaN());
+ TestDouble(std::numeric_limits<double>::denorm_min());
+ TestDouble(-std::numeric_limits<double>::denorm_min());
+ // Test exact encoding: on currently supported platforms, EncodeDouble
+ // should produce exactly the same as the in-memory representation for non-NaN.
+ for (int j = 0; j < 1000; ++j) {
+ // Iterate over 9 specific bits exhaustively; the others are chosen randomly.
+ // These specific bits are the sign bit, and the 2 top and bottom bits of
+ // exponent and mantissa in the IEEE754 binary64 format.
+ for (int x = 0; x < 512; ++x) {
+ uint64_t v = InsecureRandBits(64);
+ v &= ~(uint64_t{1} << 0);
+ if (x & 1) v |= (uint64_t{1} << 0);
+ v &= ~(uint64_t{1} << 1);
+ if (x & 2) v |= (uint64_t{1} << 1);
+ v &= ~(uint64_t{1} << 50);
+ if (x & 4) v |= (uint64_t{1} << 50);
+ v &= ~(uint64_t{1} << 51);
+ if (x & 8) v |= (uint64_t{1} << 51);
+ v &= ~(uint64_t{1} << 52);
+ if (x & 16) v |= (uint64_t{1} << 52);
+ v &= ~(uint64_t{1} << 53);
+ if (x & 32) v |= (uint64_t{1} << 53);
+ v &= ~(uint64_t{1} << 61);
+ if (x & 64) v |= (uint64_t{1} << 61);
+ v &= ~(uint64_t{1} << 62);
+ if (x & 128) v |= (uint64_t{1} << 62);
+ v &= ~(uint64_t{1} << 63);
+ if (x & 256) v |= (uint64_t{1} << 63);
+ double f;
+ memcpy(&f, &v, 8);
+ uint64_t v2 = TestDouble(f);
+ if (!std::isnan(f)) BOOST_CHECK_EQUAL(v, v2);
+ }
+ }
+ }
+}
+
+BOOST_AUTO_TEST_SUITE_END()