diff --git a/src/share/vm/opto/type.cpp b/src/share/vm/opto/type.cpp index 685f41715562f171f355728112c51c899cbd743d..6076a56d201a2f8dc591d87e1368dde9a5918c6c 100644 --- a/src/share/vm/opto/type.cpp +++ b/src/share/vm/opto/type.cpp @@ -1001,21 +1001,10 @@ const Type *TypeF::xdual() const { //------------------------------eq--------------------------------------------- // Structural equality check for Type representations -bool TypeF::eq( const Type *t ) const { - if( g_isnan(_f) || - g_isnan(t->getf()) ) { - // One or both are NANs. If both are NANs return true, else false. - return (g_isnan(_f) && g_isnan(t->getf())); - } - if (_f == t->getf()) { - // (NaN is impossible at this point, since it is not equal even to itself) - if (_f == 0.0) { - // difference between positive and negative zero - if (jint_cast(_f) != jint_cast(t->getf())) return false; - } - return true; - } - return false; +bool TypeF::eq(const Type *t) const { + // Bitwise comparison to distinguish between +/-0. These values must be treated + // as different to be consistent with C1 and the interpreter. + return (jint_cast(_f) == jint_cast(t->getf())); } //------------------------------hash------------------------------------------- @@ -1116,21 +1105,10 @@ const Type *TypeD::xdual() const { //------------------------------eq--------------------------------------------- // Structural equality check for Type representations -bool TypeD::eq( const Type *t ) const { - if( g_isnan(_d) || - g_isnan(t->getd()) ) { - // One or both are NANs. If both are NANs return true, else false. - return (g_isnan(_d) && g_isnan(t->getd())); - } - if (_d == t->getd()) { - // (NaN is impossible at this point, since it is not equal even to itself) - if (_d == 0.0) { - // difference between positive and negative zero - if (jlong_cast(_d) != jlong_cast(t->getd())) return false; - } - return true; - } - return false; +bool TypeD::eq(const Type *t) const { + // Bitwise comparison to distinguish between +/-0. These values must be treated + // as different to be consistent with C1 and the interpreter. + return (jlong_cast(_d) == jlong_cast(t->getd())); } //------------------------------hash------------------------------------------- diff --git a/test/compiler/c2/FloatingPointFoldingTest.java b/test/compiler/c2/FloatingPointFoldingTest.java new file mode 100644 index 0000000000000000000000000000000000000000..cb3ce01c96b5c86926dd0174df7ba3c46157f1a7 --- /dev/null +++ b/test/compiler/c2/FloatingPointFoldingTest.java @@ -0,0 +1,163 @@ +/* + * Copyright (c) 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 + * @bug 8073670 + * @summary Test that causes C2 to fold two NaNs with different values into a single NaN. + * @run main/othervm -XX:-TieredCompilation -Xcomp -XX:CompileCommand=compileonly,FloatingPointFoldingTest.test_double_inf -XX:CompileCommand=compileonly,FloatingPointFoldingTest.test_double_zero -XX:CompileCommand=compileonly,FloatingPointFoldingTest.test_double_nan -XX:CompileCommand=compileonly,FloatingPointFoldingTest.test_float_inf -XX:CompileCommand=compileonly,FloatingPointFoldingTest.test_float_zero -XX:CompileCommand=compileonly,FloatingPointFoldingTest.test_float_nan FloatingPointFoldingTest + */ + +public class FloatingPointFoldingTest { + // Double values. + public static final long MINUS_INF_LONGBITS = 0xfff0000000000000L; + public static final double DOUBLE_MINUS_INF = Double.longBitsToDouble(MINUS_INF_LONGBITS); + + public static final long PLUS_INF_LONGBITS = 0x7ff0000000000000L; + public static final double DOUBLE_PLUS_INF = Double.longBitsToDouble(PLUS_INF_LONGBITS); + + public static final long MINUS_ZERO_LONGBITS = 0x8000000000000000L; + public static final double DOUBLE_MINUS_ZERO = Double.longBitsToDouble(MINUS_ZERO_LONGBITS); + + // We need two different NaN values. A floating point number is + // considered to be NaN is the sign bit is 0, all exponent bits + // are set to 1, and at least one bit of the exponent is not zero. + // + // As java.lang.Double.NaN is 0x7ff8000000000000L, we use + // 0x7ffc000000000000L as a second NaN double value. + public static final long NAN_LONGBITS = 0x7ffc000000000000L; + public static final double DOUBLE_NAN = Double.longBitsToDouble(NAN_LONGBITS); + + // Float values. + public static final int MINUS_INF_INTBITS = 0xff800000; + public static final float FLOAT_MINUS_INF = Float.intBitsToFloat(MINUS_INF_INTBITS); + + public static final int PLUS_INF_INTBITS = 0x7f800000; + public static final float FLOAT_PLUS_INF = Float.intBitsToFloat(PLUS_INF_INTBITS); + + public static final int MINUS_ZERO_INTBITS = 0x80000000; + public static final float FLOAT_MINUS_ZERO = Float.intBitsToFloat(MINUS_ZERO_INTBITS); + + // As java.lang.Float.NaN is 0x7fc00000, we use 0x7fe00000 + // as a second NaN float value. + public static final int NAN_INTBITS = 0x7fe00000; + public static final float FLOAT_NAN = Float.intBitsToFloat(NAN_INTBITS); + + + // Double tests. + static void test_double_inf(long[] result) { + double d1 = DOUBLE_MINUS_INF; + double d2 = DOUBLE_PLUS_INF; + result[0] = Double.doubleToRawLongBits(d1); + result[1] = Double.doubleToRawLongBits(d2); + } + + static void test_double_zero(long[] result) { + double d1 = DOUBLE_MINUS_ZERO; + double d2 = 0; + result[0] = Double.doubleToRawLongBits(d1); + result[1] = Double.doubleToRawLongBits(d2); + } + + static void test_double_nan(long[] result) { + double d1 = DOUBLE_NAN; + double d2 = Double.NaN; + result[0] = Double.doubleToRawLongBits(d1); + result[1] = Double.doubleToRawLongBits(d2); + } + + // Float tests. + static void test_float_inf(int[] result) { + float f1 = FLOAT_MINUS_INF; + float f2 = FLOAT_PLUS_INF; + result[0] = Float.floatToRawIntBits(f1); + result[1] = Float.floatToRawIntBits(f2); + } + + static void test_float_zero(int[] result) { + float f1 = FLOAT_MINUS_ZERO; + float f2 = 0; + result[0] = Float.floatToRawIntBits(f1); + result[1] = Float.floatToRawIntBits(f2); + } + + static void test_float_nan(int[] result) { + float f1 = FLOAT_NAN; + float f2 = Float.NaN; + result[0] = Float.floatToRawIntBits(f1); + result[1] = Float.floatToRawIntBits(f2); + } + + // Check doubles. + static void check_double(long[] result, double d1, double d2) { + if (result[0] == result[1]) { + throw new RuntimeException("ERROR: Two different double values are considered equal. \n" + + String.format("\toriginal values: 0x%x 0x%x\n", Double.doubleToRawLongBits(d1), Double.doubleToRawLongBits(d2)) + + String.format("\tvalues after execution of method test(): 0x%x 0x%x", result[0], result[1])); + } + } + + // Check floats. + static void check_float(int[] result, float f1, float f2) { + if (result[0] == result[1]) { + throw new RuntimeException("ERROR: Two different float values are considered equal. \n" + + String.format("\toriginal values: 0x%x 0x%x\n", Float.floatToRawIntBits(f1), Float.floatToRawIntBits(f2)) + + String.format("\tvalues after execution of method test(): 0x%x 0x%x", result[0], result[1])); + } + } + + public static void main(String[] args) { + // Float tests. + + int[] iresult = new int[2]; + + // -Inf and +Inf. + test_float_inf(iresult); + check_float(iresult, FLOAT_MINUS_INF, FLOAT_PLUS_INF); + + // 0 and -0. + test_float_zero(iresult); + check_float(iresult, FLOAT_MINUS_ZERO, 0); + + // Diferrent NaNs. + test_float_nan(iresult); + check_float(iresult, FLOAT_NAN, Float.NaN); + + // Double tests. + + long[] lresult = new long[2]; + + // -Inf and +Inf. + test_double_inf(lresult); + check_double(lresult, DOUBLE_MINUS_INF, DOUBLE_PLUS_INF); + + // 0 and -0. + test_double_zero(lresult); + check_double(lresult, DOUBLE_MINUS_ZERO, 0); + + // Diferrent NaNs. + test_double_nan(lresult); + check_double(lresult, DOUBLE_NAN, Double.NaN); + } +}