test/hotspot/jtreg/compiler/loopopts/TestBackedgeLoadArrayFill.jasm

/*
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 * 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.
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super public class TestBackedgeLoadArrayFill
{
    public Method "<init>":"()V"
    stack 2 locals 1
    {
        aload_0;
        invokespecial  Method java/lang/Object."<init>":"()V";
        return;
    }

    static Method test_101:"()V"
    stack 20 locals 20
    {
        // test_002 in jasm: using try-catch
        ldc 6;
        istore_0; // i = 6
        ldc 25;
        newarray int;
        astore_1; // arr = new int[25]
    HEAD:
        aload_1;
        iload_0;
        iconst_1;
        iastore; // arr[i] = 1
        // second block - the only one -> head block can be copied: one before, one on backedge
        try t0;
        aload_1;
        iload_0;
        aload_1;
        iload_0;
        iaload;
        iastore; // arr[i] = arr[i]
        goto FINALLY;
        endtry t0;
        catch t0 java/lang/Exception;
        pop; // exception
    FINALLY:
        iinc 0, 1; // i++
        iload_0;
        ldc 21;
        if_icmplt HEAD; // if i < 21
        // write array
        aload_1;
        putstatic Field TestBackedgeLoadArrayFillMain.intA:"[I";
        return;
    }

    static Method test_102:"()V"
    stack 20 locals 20
    {
        // test_002 in jasm: without try-catch
        ldc 5;
        istore_0; // i = 5
        ldc 25;
        newarray int;
        astore_1; // arr = new int[25]
    HEAD:
        aload_1;
        iload_0;
        iconst_1;
        iastore; // arr[i] = 1
        goto SECOND;
        // second block - the only one -> head block can be copied: one before, one on backedge
        // must have some material before inc, else it is partial peeled away
        // And if we set -XX:-PartialPeelLoop, then the counted loop is never detected
    SECOND:
        aload_1;
        iload_0;
        aload_1;
        iload_0;
        iaload;
        iastore; // arr[i] = arr[i]
        iinc 0, 1; // i++
        iload_0;
        ldc 21;
        if_icmplt HEAD; // if i < 21
        // write array
        aload_1;
        putstatic Field TestBackedgeLoadArrayFillMain.intA:"[I";
        return;
    }

    static Method test_103:"()V"
    stack 20 locals 20
    {
        // test_002 in jasm: without try-catch, and second array
        ldc 7;
        istore_0; // i = 7
        ldc 25;
        newarray int;
        astore_1; // arr = new int[25]
        ldc 25;
        newarray int;
        astore_2; // arr2 = new int[25]
    HEAD:
        aload_1;
        iload_0;
        iconst_1;
        iastore; // arr[i] = 1
        goto SECOND;
        // second block - the only one -> head block can be copied: one before, one on backedge
    SECOND:
        // we can also do the identity read-write on another array - it just has to eventually disappear
        aload_2;
        iload_0;
        aload_2;
        iload_0;
        iaload;
        iastore; // arr2[i] = arr2[i]

        iinc 0, 1; // i++
        iload_0;
        ldc 21;
        if_icmplt HEAD; // if i < 21
        // write array
        aload_1;
        putstatic Field TestBackedgeLoadArrayFillMain.intA:"[I";
        return;
    }

    static Method test_104:"()V"
    stack 20 locals 20
    {
        ldc 9;
        istore_0; // i = 9
        ldc 25;
        newarray int;
        astore_1; // arr = new int[25]
    HEAD:
        aload_1;
        iload_0;
        iconst_1;
        iastore; // arr[i] = 1
        goto SECOND;
        // second block - the only one -> head block can be copied: one before, one on backedge
    SECOND:
        // CFG leads to partial peel -> load moved into loop body, then intrinsified
        iload_0;
        ldc 2;
        irem;
        ifeq SKIP;

    SKIP:

        iinc 0, 1; // i++
        iload_0;
        ldc 21;
        if_icmplt HEAD; // if i < 21
        // write array
        aload_1;
        putstatic Field TestBackedgeLoadArrayFillMain.intA:"[I";
        return;
    }
}