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/*
* Copyright (c) 2002, 2020, 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
*
* @summary converted from VM Testbase runtime/jbe/dead/dead01.
* VM Testbase keywords: [quick, runtime]
*
* @library /vmTestbase
* /test/lib
* @run main/othervm vm.compiler.jbe.dead.dead01.dead01
*/
package vm.compiler.jbe.dead.dead01;
/* -- Test the elimination of dead assignment to local variables
In the example below, the value assigned to i is never used, all dead stores to local can be eliminated, and the last return statement in f() is unreachable; Both dead/unused stores and unreachable statement can be eliminated.
*/
public class dead01 {
public static void main(String args[]) {
dead01 dce = new dead01();
System.out.println("f()="+dce.f()+"; fopt()="+dce.fopt());
if (dce.f() == dce.fopt()) {
System.out.println("Test dead01 Passed.");
} else {
throw new Error("Test dead01 Failed: f()=" + dce.f() + " != fopt()=" + dce.fopt());
}
}
int f() {
int local;
int i;
i = 1; /* dead store */
local = 8; /* dead store */
local = 7; /* dead store */
local = 6; /* dead store */
local = 5; /* dead store */
local = 4; /* dead store */
local = 3; /* dead store */
local = 2; /* dead store */
local = 1; /* dead store */
local = 0; /* dead store */
local = -1; /* dead store */
local = -2; /* dead store */
i = 1; /* dead store */
local = 8; /* dead store */
local = 7; /* dead store */
local = 6; /* dead store */
local = 5; /* dead store */
local = 4; /* dead store */
local = 3; /* dead store */
local = 2; /* dead store */
local = 1; /* dead store */
local = 0; /* dead store */
local = -1; /* dead store */
local = -2; /* dead store */
i = 1; /* dead store */
local = 8; /* dead store */
local = 7; /* dead store */
local = 6; /* dead store */
local = 5; /* dead store */
local = 4; /* dead store */
local = 3; /* dead store */
local = 2; /* dead store */
local = 1; /* dead store */
local = 0; /* dead store */
local = -1; /* dead store */
local = -2;
if (Math.abs(local) >= 0)
return local;
return local; /* unreachable */
}
// Code fragment after dead code elimination
static int fopt() {
int local;
local = -2;
return local;
}
}
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