/*
* Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* @test
* @library /lib/testlibrary/
* @build jdk.testlibrary.*
* @run main ParseHexFloatingPoint
* @bug 4826774 8078672
* @summary Numerical tests for hexadecimal inputs to parse{Double, Float} (use -Dseed=X to set PRNG seed)
* @author Joseph D. Darcy
* @key randomness
*/
import jdk.testlibrary.RandomFactory;
public class ParseHexFloatingPoint {
private ParseHexFloatingPoint(){}
public static final double infinityD = Double.POSITIVE_INFINITY;
public static final double NaND = Double.NaN;
static int test(String testName, String input,
double result, double expected) {
int failures =0;
if (Double.compare(result, expected) != 0 ) {
System.err.println("Failure for " + testName +
": For input " + input +
" expected " + expected +
" got " + result + ".");
}
return failures;
}
static int testCase(String input, double expected) {
int failures =0;
// Try different combination of letter components
input = input.toLowerCase(java.util.Locale.US);
String [] suffices = {"", "f", "F", "d", "D"};
String [] signs = {"", "-", "+"};
for(int i = 0; i < 2; i++) {
String s1 = input;
if(i == 1)
s1 = s1.replace('x', 'X');
for(int j = 0; j < 2; j++) {
String s2 = s1;
if(j == 1)
s2 = s2.replace('p', 'P');
for(int k = 0; k < 2; k++) {
String s3 = s2;
if(k == 1)
s3 = upperCaseHex(s3);
for(int m = 0; m < suffices.length; m++) {
String s4 = s3 + suffices[m];
for(int n = 0; n < signs.length; n++) {
String s5 = signs[n] + s4;
double result = Double.parseDouble(s5);
failures += test("Double.parseDouble",
s5, result, (signs[n].equals("-") ?
-expected:
expected));
}
}
}
}
}
return failures;
}
static String upperCaseHex(String s) {
return s.replace('a', 'A').replace('b', 'B').replace('c', 'C').
replace('d', 'D').replace('e','E').replace('f', 'F');
}
/*
* Test easy and tricky double rounding cases.
*/
static int doubleTests() {
/*
* A String, double pair
*/
class PairSD {
public String s;
public double d;
PairSD(String s, double d) {
this.s = s;
this.d = d;
}
}
int failures = 0;
// Hex strings that convert to three; test basic functionality
// of significand and exponent shift adjusts along with the
// no-op of adding leading zeros. These cases don't exercise
// the rounding code.
String leadingZeros = "0x0000000000000000000";
String [] threeTests = {
"0x.003p12",
"0x.006p11",
"0x.00cp10",
"0x.018p9",
"0x.3p4",
"0x.6p3",
"0x.cp2",
"0x1.8p1",
"0x3p0",
"0x6.0p-1",
"0xc.0p-2",
"0x18.0p-3",
"0x3000000p-24",
"0x3.0p0",
"0x3.000000p0",
};
for(int i=0; i < threeTests.length; i++) {
String input = threeTests[i];
failures += testCase(input, 3.0);
input.replaceFirst("^0x", leadingZeros);
failures += testCase(input, 3.0);
}
long bigExponents [] = {
2*Double.MAX_EXPONENT,
2*Double.MIN_EXPONENT,
(long)Integer.MAX_VALUE-1,
(long)Integer.MAX_VALUE,
(long)Integer.MAX_VALUE+1,
(long)Integer.MIN_VALUE-1,
(long)Integer.MIN_VALUE,
(long)Integer.MIN_VALUE+1,
Long.MAX_VALUE-1,
Long.MAX_VALUE,
Long.MIN_VALUE+1,
Long.MIN_VALUE,
};
// Test zero significand with large exponents.
for(int i = 0; i < bigExponents.length; i++) {
failures += testCase("0x0.0p"+Long.toString(bigExponents[i]) , 0.0);
}
// Test nonzero significand with large exponents.
for(int i = 0; i < bigExponents.length; i++) {
long exponent = bigExponents[i];
failures += testCase("0x10000.0p"+Long.toString(exponent) ,
(exponent <0?0.0:infinityD));
}
// Test significands with different lengths and bit patterns.
{
long signif = 0;
for(int i = 1; i <= 0xe; i++) {
signif = (signif <<4) | (long)i;
failures += testCase("0x"+Long.toHexString(signif)+"p0", signif);
}
}
PairSD [] testCases = {
new PairSD("0x0.0p0", 0.0/16.0),
new PairSD("0x0.1p0", 1.0/16.0),
new PairSD("0x0.2p0", 2.0/16.0),
new PairSD("0x0.3p0", 3.0/16.0),
new PairSD("0x0.4p0", 4.0/16.0),
new PairSD("0x0.5p0", 5.0/16.0),
new PairSD("0x0.6p0", 6.0/16.0),
new PairSD("0x0.7p0", 7.0/16.0),
new PairSD("0x0.8p0", 8.0/16.0),
new PairSD("0x0.9p0", 9.0/16.0),
new PairSD("0x0.ap0", 10.0/16.0),
new PairSD("0x0.bp0", 11.0/16.0),
new PairSD("0x0.cp0", 12.0/16.0),
new PairSD("0x0.dp0", 13.0/16.0),
new PairSD("0x0.ep0", 14.0/16.0),
new PairSD("0x0.fp0", 15.0/16.0),
// Half-way case between zero and MIN_VALUE rounds down to
// zero
new PairSD("0x1.0p-1075", 0.0),
// Slighly more than half-way case between zero and
// MIN_VALUES rounds up to zero.
new PairSD("0x1.1p-1075", Double.MIN_VALUE),
new PairSD("0x1.000000000001p-1075", Double.MIN_VALUE),
new PairSD("0x1.000000000000001p-1075", Double.MIN_VALUE),
// More subnormal rounding tests
new PairSD("0x0.fffffffffffff7fffffp-1022", Math.nextDown(Double.MIN_NORMAL)),
new PairSD("0x0.fffffffffffff8p-1022", Double.MIN_NORMAL),
new PairSD("0x0.fffffffffffff800000001p-1022",Double.MIN_NORMAL),
new PairSD("0x0.fffffffffffff80000000000000001p-1022",Double.MIN_NORMAL),
new PairSD("0x1.0p-1022", Double.MIN_NORMAL),
// Large value and overflow rounding tests
new PairSD("0x1.fffffffffffffp1023", Double.MAX_VALUE),
new PairSD("0x1.fffffffffffff0000000p1023", Double.MAX_VALUE),
new PairSD("0x1.fffffffffffff4p1023", Double.MAX_VALUE),
new PairSD("0x1.fffffffffffff7fffffp1023", Double.MAX_VALUE),
new PairSD("0x1.fffffffffffff8p1023", infinityD),
new PairSD("0x1.fffffffffffff8000001p1023", infinityD),
new PairSD("0x1.ffffffffffffep1023", Math.nextDown(Double.MAX_VALUE)),
new PairSD("0x1.ffffffffffffe0000p1023", Math.nextDown(Double.MAX_VALUE)),
new PairSD("0x1.ffffffffffffe8p1023", Math.nextDown(Double.MAX_VALUE)),
new PairSD("0x1.ffffffffffffe7p1023", Math.nextDown(Double.MAX_VALUE)),
new PairSD("0x1.ffffffffffffeffffffp1023", Double.MAX_VALUE),
new PairSD("0x1.ffffffffffffe8000001p1023", Double.MAX_VALUE),
};
for (int i = 0; i < testCases.length; i++) {
failures += testCase(testCases[i].s,testCases[i].d);
}
failures += significandAlignmentTests();
{
java.util.Random rand = RandomFactory.getRandom();
// Consistency check; double => hexadecimal => double
// preserves the original value.
for(int i = 0; i < 1000; i++) {
double d = rand.nextDouble();
failures += testCase(Double.toHexString(d), d);
}
}
return failures;
}
/*
* Verify rounding works the same regardless of how the
* significand is aligned on input. A useful extension could be
* to have this sort of test for strings near the overflow
* threshold.
*/
static int significandAlignmentTests() {
int failures = 0;
// baseSignif * 2^baseExp = nextDown(2.0)
long [] baseSignifs = {
0x1ffffffffffffe00L,
0x1fffffffffffff00L
};
double [] answers = {
Math.nextDown(Math.nextDown(2.0)),
Math.nextDown(2.0),
2.0
};
int baseExp = -60;
int count = 0;
for(int i = 0; i < 2; i++) {
for(long j = 0; j <= 0xfL; j++) {
for(long k = 0; k <= 8; k+= 4) { // k = {0, 4, 8}
long base = baseSignifs[i];
long testValue = base | (j<<4) | k;
int offset = 0;
// Calculate when significand should be incremented
// see table 4.7 in Koren book
if ((base & 0x100L) == 0L ) { // lsb is 0
if ( (j >= 8L) && // round is 1
((j & 0x7L) != 0 || k != 0 ) ) // sticky is 1
offset = 1;
}
else { // lsb is 1
if (j >= 8L) // round is 1
offset = 1;
}
double expected = answers[i+offset];
for(int m = -2; m <= 3; m++) {
count ++;
// Form equal value string and evaluate it
String s = "0x" +
Long.toHexString((m >=0) ?(testValue<<m):(testValue>>(-m))) +
"p" + (baseExp - m);
failures += testCase(s, expected);
}
}
}
}
return failures;
}
/*
* Test tricky float rounding cases. The code which
* reads in a hex string converts the string to a double value.
* If a float value is needed, the double value is cast to float.
* However, the cast be itself not always guaranteed to return the
* right result since:
*
* 1. hex string => double can discard a sticky bit which would
* influence a direct hex string => float conversion.
*
* 2. hex string => double => float can have a rounding to double
* precision which results in a larger float value while a direct
* hex string => float conversion would not round up.
*
* This method includes tests of the latter two possibilities.
*/
static int floatTests(){
int failures = 0;
/*
* A String, float pair
*/
class PairSD {
public String s;
public float f;
PairSD(String s, float f) {
this.s = s;
this.f = f;
}
}
String [][] roundingTestCases = {
// Target float value hard rouding version
{"0x1.000000p0", "0x1.0000000000001p0"},
// Try some values that should round up to nextUp(1.0f)
{"0x1.000002p0", "0x1.0000010000001p0"},
{"0x1.000002p0", "0x1.00000100000008p0"},
{"0x1.000002p0", "0x1.0000010000000fp0"},
{"0x1.000002p0", "0x1.00000100000001p0"},
{"0x1.000002p0", "0x1.00000100000000000000000000000000000000001p0"},
{"0x1.000002p0", "0x1.0000010000000fp0"},
// Potential double rounding cases
{"0x1.000002p0", "0x1.000002fffffffp0"},
{"0x1.000002p0", "0x1.000002fffffff8p0"},
{"0x1.000002p0", "0x1.000002ffffffffp0"},
{"0x1.000002p0", "0x1.000002ffff0ffp0"},
{"0x1.000002p0", "0x1.000002ffff0ff8p0"},
{"0x1.000002p0", "0x1.000002ffff0fffp0"},
{"0x1.000000p0", "0x1.000000fffffffp0"},
{"0x1.000000p0", "0x1.000000fffffff8p0"},
{"0x1.000000p0", "0x1.000000ffffffffp0"},
{"0x1.000000p0", "0x1.000000ffffffep0"},
{"0x1.000000p0", "0x1.000000ffffffe8p0"},
{"0x1.000000p0", "0x1.000000ffffffefp0"},
// Float subnormal cases
{"0x0.000002p-126", "0x0.0000010000001p-126"},
{"0x0.000002p-126", "0x0.00000100000000000001p-126"},
{"0x0.000006p-126", "0x0.0000050000001p-126"},
{"0x0.000006p-126", "0x0.00000500000000000001p-126"},
{"0x0.0p-149", "0x0.7ffffffffffffffp-149"},
{"0x1.0p-148", "0x1.3ffffffffffffffp-148"},
{"0x1.cp-147", "0x1.bffffffffffffffp-147"},
{"0x1.fffffcp-127", "0x1.fffffdffffffffp-127"},
};
String [] signs = {"", "-"};
for(int i = 0; i < roundingTestCases.length; i++) {
for(int j = 0; j < signs.length; j++) {
String expectedIn = signs[j]+roundingTestCases[i][0];
String resultIn = signs[j]+roundingTestCases[i][1];
float expected = Float.parseFloat(expectedIn);
float result = Float.parseFloat(resultIn);
if( Float.compare(expected, result) != 0) {
failures += 1;
System.err.println("" + (i+1));
System.err.println("Expected = " + Float.toHexString(expected));
System.err.println("Rounded = " + Float.toHexString(result));
System.err.println("Double = " + Double.toHexString(Double.parseDouble(resultIn)));
System.err.println("Input = " + resultIn);
System.err.println("");
}
}
}
return failures;
}
public static void main(String argv[]) {
int failures = 0;
failures += doubleTests();
failures += floatTests();
if (failures != 0) {
throw new RuntimeException("" + failures + " failures while " +
"testing hexadecimal floating-point " +
"parsing.");
}
}
}