bug fix of posit binary printing

stillwater-sc · May 3, 2023 · 40ef3ad · 40ef3ad
1 parent ec7067c
commit 40ef3ad
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Showing 3 changed files with 50 additions and 10 deletions.
diff --git a/include/universal/number/posit/manipulators.hpp b/include/universal/number/posit/manipulators.hpp
@@ -186,7 +186,7 @@ std::string color_print(const posit<nbits, es>& p) {
 	regime<nbits, es>    _regime;
 	exponent<nbits, es>  _exponent;
 	fraction<fbits>      _fraction;
-	decode(p.get(), _sign, _regime, _exponent, _fraction);
+	extract_fields(p.get(), _sign, _regime, _exponent, _fraction);
 
 	Color red(ColorCode::FG_RED);
 	Color yellow(ColorCode::FG_YELLOW);
@@ -197,13 +197,18 @@ std::string color_print(const posit<nbits, es>& p) {
 	Color def(ColorCode::FG_DEFAULT);
 	str << red << (p.isneg() ? "1" : "0");
 
-	bitblock<nbits - 1> r = _regime.get();
-	int regimeBits = (int)_regime.nrBits();
-	int nrOfRegimeBitsProcessed = 0;
-	for (unsigned i = 0; i < nbits - 1; ++i) {
-		unsigned bitIndex = nbits - 2u - i;
-		if (regimeBits > nrOfRegimeBitsProcessed++) {
-			str << yellow << (_sign ? (r[bitIndex] ? '0' : '1') : (r[bitIndex] ? '1' : '0'));
+	if (p.isnar()) {
+		for (unsigned i = 0; i < nbits - 1; ++i) str << yellow << '0';
+	}
+	else {
+		bitblock<nbits - 1> r = _regime.get();
+		int regimeBits = (int)_regime.nrBits();
+		int nrOfRegimeBitsProcessed = 0;
+		for (unsigned i = 0; i < nbits - 1; ++i) {
+			unsigned bitIndex = nbits - 2u - i;
+			if (regimeBits > nrOfRegimeBitsProcessed++) {
+				str << yellow << (_sign ? (r[bitIndex] ? '0' : '1') : (r[bitIndex] ? '1' : '0'));
+			}
 		}
 	}
 

diff --git a/include/universal/number/posit/posit_impl.hpp b/include/universal/number/posit/posit_impl.hpp
@@ -144,7 +144,16 @@ int decode_regime(const internal::bitblock<nbits>& raw_bits) {
 // extract_fields takes a raw posit encoding and extracts the sign, regime, exponent, and fraction components
 template<unsigned nbits, unsigned es, unsigned fbits>
 void extract_fields(const bitblock<nbits>& raw_bits, bool& _sign, regime<nbits, es>& _regime, exponent<nbits, es>& _exponent, fraction<fbits>& _fraction) {
-	// check special case
+	// check special cases
+	bitblock<nbits> nar;
+	nar[nbits - 1] = true;
+	if (raw_bits == nar) {
+		_sign = true;
+		_regime.setzero();
+		_exponent.setzero();
+		_fraction.setzero();
+		return;
+	}
 	bitblock<nbits> zero;
 	if (raw_bits == zero) {
 		_sign = false;
@@ -204,8 +213,9 @@ void decode(const bitblock<nbits>& raw_bits, bool& _sign, regime<nbits, es>& _re
 		if (tmp.none()) {
 			// setnar();   special case = NaR (Not a Real)
 			_sign = true;
-			_regime.setinf();
+			_regime.setzero();
 			_exponent.reset();
+			_fraction.reset();
 		}
 		else {
 			extract_fields(raw_bits, _sign, _regime, _exponent, _fraction);

diff --git a/static/posit/api/api.cpp b/static/posit/api/api.cpp
@@ -16,6 +16,7 @@
 #define POSIT_ERROR_FREE_IO_FORMAT 0
 // minimum set of include files to reflect source code dependencies
 #include <universal/number/posit/posit.hpp>
+#include <universal/verification/test_suite.hpp>
 
 int main()
 try {
@@ -57,6 +58,30 @@ try {
 		std::cout << "standard posit  : " << type_tag(posit<256, 2>()) << '\n';
 	}
 
+	// special cases
+	{
+		using Posit = posit<8, 0>;
+		Posit a;
+		a.setnar();  ReportValue(a, "NaR    : ");
+		a.maxpos();  ReportValue(a, "maxpos : ");
+		a = 1;       ReportValue(a, "  1    : ");
+		a.minpos();  ReportValue(a, "minpos : ");
+		a.setzero(); ReportValue(a, "zero   : ");
+		a.minneg();  ReportValue(a, "minneg : ");
+		a = -1;      ReportValue(a, " -1    : ");
+		a.maxneg();  ReportValue(a, "maxneg : ");
+	}
+
+	// color printing
+	{
+		using Posit = posit<5, 1>;
+		Posit a;
+		for (unsigned i = 0; i < 32; ++i) {
+			a.setbits(i);
+			std::cout << to_binary(a) << " : " << color_print(a) << " : " << a << '\n';
+		}
+	}
+
 	/////////////////////////////////////////////////////////////////////////////////////
 	//// improving efficiency for posits through explicit BlockType specification