From 3db344b0bd33e433e4e2126606b6bdab14cab1c4 Mon Sep 17 00:00:00 2001
From: Ravenwater <theo@stillwater-sc.com>
Date: Thu, 15 Aug 2024 16:13:53 -0400
Subject: [PATCH] adding sqrt regression test to quad-double

---
 static/qd/api/constants.cpp |   2 +-
 static/qd/math/sqrt.cpp     | 121 ++++++++++++++++++++++++++++++++++++
 2 files changed, 122 insertions(+), 1 deletion(-)
 create mode 100644 static/qd/math/sqrt.cpp

diff --git a/static/qd/api/constants.cpp b/static/qd/api/constants.cpp
index 407a679dd..74f801401 100644
--- a/static/qd/api/constants.cpp
+++ b/static/qd/api/constants.cpp
@@ -109,7 +109,7 @@ namespace sw {
 
 		void FindRepresentationForOneThird() {
 			double _third = 0.333'333'333'333'333'333'333'333'333'333'3;
-			double _third2 = _third * pow(2.0, -53.0);
+			double _third2 = _third * std::pow(2.0, -53.0);
 			double _short = 0.333'333'333'333'333'3;
 			ReportValue(_short, "0.333'333'333'333'333'3", 35, 32);
 			ReportValue(_third, "0.333'333'333'333'333'333'333'333'333'333'3", 35, 32);
diff --git a/static/qd/math/sqrt.cpp b/static/qd/math/sqrt.cpp
new file mode 100644
index 000000000..b5518d598
--- /dev/null
+++ b/static/qd/math/sqrt.cpp
@@ -0,0 +1,121 @@
+// sqrt.cpp: test suite runner for sqrt function for quad-double (qd) floating-point
+//
+// Copyright (C) 2017 Stillwater Supercomputing, Inc.
+// SPDX-License-Identifier: MIT
+//
+// This file is part of the universal numbers project, which is released under an MIT Open Source license.
+#include <universal/utility/directives.hpp>
+#include <universal/number/qd/qd.hpp>
+#include <universal/verification/test_suite.hpp>
+
+
+namespace sw {
+	namespace universal {
+
+		template<typename Ty>
+		void GenerateSqrtTestCase(Ty fa) {
+			unsigned precision = 25;
+			//unsigned width = 30;
+			Ty fref;
+			sw::universal::qd a, ref, v;
+			a = fa;
+			fref = std::sqrt(fa);
+			ref = fref;
+			v = sw::universal::sqrt(a);
+			auto oldPrec = std::cout.precision();
+			std::cout << std::setprecision(precision);
+			std::cout << " -> sqrt(" << fa << ") = " << fref << std::endl;
+			std::cout << " -> sqrt( " << a << ") = " << v << '\n' << to_binary(v) << '\n';
+			std::cout << to_binary(ref) << "\n -> reference\n";
+			std::cout << (ref == v ? "PASS" : "FAIL") << std::endl << std::endl;
+			std::cout << std::setprecision(oldPrec);
+		}
+
+		template<typename QuadDouble>
+		int VerifySqrtFunction(bool reportTestCases, QuadDouble a) {
+			int nrOfFailedTestCases{ 0 };
+			QuadDouble b{ a };
+			for (int i = 0; i < 9; ++i) {
+				a *= a;
+				qd c = sqrt(a);
+				if (b != c) {
+					if (reportTestCases) std::cerr << "FAIL : " << b << " != " << c << '\n';
+					++nrOfFailedTestCases;
+				}
+				b *= b;
+			}
+			return nrOfFailedTestCases;
+		}
+	}
+}
+
+
+// Regression testing guards: typically set by the cmake configuration, but MANUAL_TESTING is an override
+#define MANUAL_TESTING 0
+// REGRESSION_LEVEL_OVERRIDE is set by the cmake file to drive a specific regression intensity
+// It is the responsibility of the regression test to organize the tests in a quartile progression.
+//#undef REGRESSION_LEVEL_OVERRIDE
+#ifndef REGRESSION_LEVEL_OVERRIDE
+#undef REGRESSION_LEVEL_1
+#undef REGRESSION_LEVEL_2
+#undef REGRESSION_LEVEL_3
+#undef REGRESSION_LEVEL_4
+#define REGRESSION_LEVEL_1 1
+#define REGRESSION_LEVEL_2 1
+#define REGRESSION_LEVEL_3 1
+#define REGRESSION_LEVEL_4 1
+#endif
+
+int main()
+try {
+	using namespace sw::universal;
+
+	std::string test_suite  = "quad-double mathlib sqrt function validation";
+	std::string test_tag    = "sqrt";
+	bool reportTestCases    = true;
+	int nrOfFailedTestCases = 0;
+
+	ReportTestSuiteHeader(test_suite, reportTestCases);
+
+#if MANUAL_TESTING
+	// generate individual testcases to hand trace/debug
+	GenerateSqrtTestCase<double>(1.0);
+	GenerateSqrtTestCase<double>(1024.0 * 1024.0);
+	constexpr double minpos = std::numeric_limits<double>::min();
+	GenerateSqrtTestCase<double>(minpos);
+	constexpr double maxpos = std::numeric_limits<double>::max();
+	GenerateSqrtTestCase<double>(maxpos);
+
+	ReportTestSuiteResults(test_suite, nrOfFailedTestCases);
+	return EXIT_SUCCESS;   // ignore errors
+#else
+
+	nrOfFailedTestCases += ReportTestResult(VerifySqrtFunction<qd>(reportTestCases, qd(2.0)), "sqrt(qd > 1.0)", test_tag);
+	nrOfFailedTestCases += ReportTestResult(VerifySqrtFunction<qd>(reportTestCases, qd(0.5)), "sqrt(qd < 1.0)", test_tag);
+
+
+	ReportTestSuiteResults(test_suite, nrOfFailedTestCases);
+	return (nrOfFailedTestCases > 0 ? EXIT_FAILURE : EXIT_SUCCESS);
+
+#endif  // MANUAL_TESTING
+}
+catch (char const* msg) {
+	std::cerr << "Caught ad-hoc exception: " << msg << std::endl;
+	return EXIT_FAILURE;
+}
+catch (const sw::universal::universal_arithmetic_exception& err) {
+	std::cerr << "Caught unexpected universal arithmetic exception : " << err.what() << std::endl;
+	return EXIT_FAILURE;
+}
+catch (const sw::universal::universal_internal_exception& err) {
+	std::cerr << "Caught unexpected universal internal exception: " << err.what() << std::endl;
+	return EXIT_FAILURE;
+}
+catch (const std::runtime_error& err) {
+	std::cerr << "Caught runtime exception: " << err.what() << std::endl;
+	return EXIT_FAILURE;
+}
+catch (...) {
+	std::cerr << "Caught unknown exception" << std::endl;
+	return EXIT_FAILURE;
+}