refining numeric_limits for double-double

Author: Ravenwater

include/universal/number/dd/dd_impl.hpp

@@ -313,7 +313,7 @@ class dd {
 		return *this;
 	}
 	constexpr dd& minpos() noexcept {
-		hi = 1.0f;
+		hi = std::numeric_limits<double>::min();
 		lo = 0.0f;
 		return *this;
 	}
@@ -323,13 +323,13 @@ class dd {
 		return *this;
 	}
 	constexpr dd& minneg() noexcept {
-		hi = 1.0f;
+		hi = -std::numeric_limits<double>::min();
 		lo = 0.0f;
 		return *this;
 	}
 	constexpr dd& maxneg() noexcept {
-		hi = 1.0f;
-		lo = 0.0f;
+		hi = -1.7976931348623157e+308;
+		lo = -1.9958403095347196e+292;
 		return *this;
 	}
 

include/universal/number/dd/numeric_limits.hpp

@@ -18,8 +18,7 @@ class numeric_limits< sw::universal::dd > {
 		return DoubleDouble(radix * (numeric_limits< double >::min() / numeric_limits< double >::epsilon()));
 	} 
 	static constexpr DoubleDouble max() { // return maximum value
-		//return DoubleDouble(sw::universal::SpecificValue::maxpos);
-		return DoubleDouble(numeric_limits< double >::max());
+		return DoubleDouble(sw::universal::SpecificValue::maxpos);
 	} 
 	static constexpr DoubleDouble lowest() { // return most negative value
 		//return DoubleDouble(sw::universal::SpecificValue::maxneg);

static/dd/api/api.cpp

@@ -339,7 +339,7 @@ try {
 		}
 	}
 
-	std::cout << "+---------    numeric_limits of doubledouble vs IEEE-754   --------+\n";
+	std::cout << "+---------    numeric_limits of double-double vs IEEE-754   --------+\n";
 	{
 		std::cout << "dd(INFINITY): " << dd(INFINITY) << "\n";
 		std::cout << "dd(-INFINITY): " << dd(-INFINITY) << "\n";
@@ -360,6 +360,14 @@ try {
 		std::cout << "dd(std::numeric_limits<float>::signaling_NaN()).isnan(sw::universal::NAN_TYPE_SIGNALLING) : " << dd(std::numeric_limits<float>::signaling_NaN()).isnan(sw::universal::NAN_TYPE_SIGNALLING) << "\n";
 	}
 
+	std::cout << "+----------   numeric traits of double-double ----------+\n";
+	{
+		numberTraits<dd>(std::cout);
+		constexpr bool hasSubnormals = true;
+		using Cfloat = cfloat<1 + 11 + 105, 11, uint32_t, hasSubnormals>;
+		numberTraits<Cfloat>(std::cout);
+	}
+
 	ReportTestSuiteResults(test_suite, nrOfFailedTestCases);
 	return (nrOfFailedTestCases > 0 ? EXIT_FAILURE : EXIT_SUCCESS);
 }