提交 250f15dc 编写于 作者: Z zmajo

8074869: C2 code generator can replace -0.0f with +0.0f on Linux

Summary: Instead of 'fpclass', use cast float->int and double->long to check if value is +0.0f and +0.0d, respectively.
Reviewed-by: kvn, simonis, dlong
上级 b48812ee
......@@ -4418,11 +4418,11 @@ operand immF() %{
interface(CONST_INTER);
%}
// constant 'float +0.0'.
// Float Immediate: +0.0f.
operand immF_0() %{
predicate((n->getf() == 0) &&
(fpclassify(n->getf()) == FP_ZERO) && (signbit(n->getf()) == 0));
predicate(jint_cast(n->getf()) == 0);
match(ConF);
op_cost(0);
format %{ %}
interface(CONST_INTER);
......
......@@ -3760,13 +3760,9 @@ operand immD() %{
interface(CONST_INTER);
%}
// Double Immediate: +0.0d
operand immD0() %{
#ifdef _LP64
// on 64-bit architectures this comparision is faster
predicate(jlong_cast(n->getd()) == 0);
#else
predicate((n->getd() == 0) && (fpclass(n->getd()) == FP_PZERO));
#endif
match(ConD);
op_cost(0);
......@@ -3783,9 +3779,9 @@ operand immF() %{
interface(CONST_INTER);
%}
// Float Immediate: 0
operand immF0() %{
predicate((n->getf() == 0) && (fpclass(n->getf()) == FP_PZERO));
// Float Immediate: +0.0f
operand immF0() %{
predicate(jint_cast(n->getf()) == 0);
match(ConF);
op_cost(0);
......
......@@ -44,14 +44,6 @@
#endif // SOLARIS
#include <math.h>
#ifndef FP_PZERO
// Linux doesn't have positive/negative zero
#define FP_PZERO FP_ZERO
#endif
#if (!defined fpclass) && ((!defined SPARC) || (!defined SOLARIS))
#define fpclass fpclassify
#endif
#include <time.h>
#include <fcntl.h>
#include <dlfcn.h>
......
......@@ -48,15 +48,6 @@
# include <ieeefp.h>
#endif
# include <math.h>
#ifdef LINUX
#ifndef FP_PZERO
// Linux doesn't have positive/negative zero
#define FP_PZERO FP_ZERO
#endif
#ifndef fpclass
#define fpclass fpclassify
#endif
#endif
# include <time.h>
# include <fcntl.h>
# include <dlfcn.h>
......
......@@ -41,14 +41,6 @@
#include <wchar.h>
#include <math.h>
#ifndef FP_PZERO
// Linux doesn't have positive/negative zero
#define FP_PZERO FP_ZERO
#endif
#if (!defined fpclass)
#define fpclass fpclassify
#endif
#include <time.h>
#include <fcntl.h>
#include <dlfcn.h>
......
/*
* 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 8074869
* @summary C2 code generator can replace -0.0f with +0.0f on Linux
* @run main ConstFPVectorization 8
* @author volker.simonis@gmail.com
*
*/
public class ConstFPVectorization {
static float[] f = new float[16];
static double[] d = new double[16];
static void floatLoop(int count) {
for (int i = 0; i < count; i++) {
f[i] = -0.0f;
}
}
static void doubleLoop(int count) {
for (int i = 0; i < count; i++) {
d[i] = -0.0d;
}
}
public static void main(String args[]) {
for (int i = 0; i < 10_000; i++) {
floatLoop(Integer.parseInt(args[0]));
doubleLoop(Integer.parseInt(args[0]));
}
for (int i = 0; i < Integer.parseInt(args[0]); i++) {
if (Float.floatToRawIntBits(f[i]) != Float.floatToRawIntBits(-0.0f))
throw new Error("Float error at index " + i);
if (Double.doubleToRawLongBits(d[i]) != Double.doubleToRawLongBits(-0.0d))
throw new Error("Double error at index " + i);
}
}
}
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