Mercurial > hg > graal-jvmci-8
changeset 16169:91a5fc21f11b
don't optimize away 0.0 and -0.0
author | Tom Rodriguez <tom.rodriguez@oracle.com> |
---|---|
date | Mon, 23 Jun 2014 14:38:42 -0700 |
parents | b63f0428eb59 |
children | 8322735c7540 |
files | graal/com.oracle.graal.compiler.test/src/com/oracle/graal/compiler/test/FloatOptimizationTest.java graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/FloatAddNode.java graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/FloatSubNode.java |
diffstat | 3 files changed, 87 insertions(+), 21 deletions(-) [+] |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/graal/com.oracle.graal.compiler.test/src/com/oracle/graal/compiler/test/FloatOptimizationTest.java Mon Jun 23 14:38:42 2014 -0700 @@ -0,0 +1,85 @@ +/* + * Copyright (c) 2014, 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. + */ +package com.oracle.graal.compiler.test; + +import org.junit.*; + +/** + * Check for incorrect elimination of 0.0 and -0.0 from computations. They can affect the sign of + * the result of an add or substract. + */ +public class FloatOptimizationTest extends GraalCompilerTest { + + @Test + public void test1() { + test("test1Snippet", -0.0); + } + + @SuppressWarnings("all") + public static double test1Snippet(double x) { + return x + 0.0; + } + + @Test + public void test2() { + test("test2Snippet", -0.0f); + } + + @SuppressWarnings("all") + public static double test2Snippet(float x) { + return x + 0.0f; + } + + @Test + public void test3() { + test("test3Snippet", -0.0); + } + + @SuppressWarnings("all") + public static double test3Snippet(double x) { + return x - -0.0; + } + + @Test + public void test4() { + test("test4Snippet", -0.0f); + } + + @SuppressWarnings("all") + public static double test4Snippet(float x) { + return x - -0.0f; + } + + @Override + protected void assertDeepEquals(String message, Object expected, Object actual, double delta) { + if (expected instanceof Double && actual instanceof Double) { + double e = (double) expected; + double a = (double) actual; + if (Double.doubleToRawLongBits(a) != Double.doubleToRawLongBits(e)) { + Assert.fail((message == null ? "" : message) + "raw double bits not equal " + Double.doubleToRawLongBits(a) + " != " + Double.doubleToRawLongBits(e)); + } + } else { + super.assertDeepEquals(message, expected, actual, delta); + } + } +}
--- a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/FloatAddNode.java Mon Jun 23 18:30:49 2014 +0200 +++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/FloatAddNode.java Mon Jun 23 14:38:42 2014 -0700 @@ -55,12 +55,8 @@ } if (x().isConstant()) { return ConstantNode.forPrimitive(evalConst(x().asConstant(), y().asConstant()), graph()); - } else if (y().isConstant()) { - Constant c = y().asConstant(); - if ((c.getKind() == Kind.Float && c.asFloat() == 0.0f) || (c.getKind() == Kind.Double && c.asDouble() == 0.0)) { - return x(); - } } + // Constant 0.0 can't be eliminated since it can affect the sign of the result. return this; }
--- a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/FloatSubNode.java Mon Jun 23 18:30:49 2014 +0200 +++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/FloatSubNode.java Mon Jun 23 14:38:42 2014 -0700 @@ -55,23 +55,8 @@ } if (x().isConstant() && y().isConstant()) { return ConstantNode.forPrimitive(evalConst(x().asConstant(), y().asConstant()), graph()); - } else if (y().isConstant()) { - Constant c = y().asConstant(); - if (c.getKind() == Kind.Float) { - float f = c.asFloat(); - if (f == 0.0f) { - return x(); - } - return graph().unique(new FloatAddNode(stamp(), x(), ConstantNode.forFloat(-f, graph()), isStrictFP())); - } else { - assert c.getKind() == Kind.Double; - double d = c.asDouble(); - if (d == 0.0) { - return x(); - } - return graph().unique(new FloatAddNode(stamp(), x(), ConstantNode.forDouble(-d, graph()), isStrictFP())); - } } + // Constant 0.0 can't be eliminated since it can affect the sign of the result. return this; }