TestOnlyInfiniteLoops.jasm

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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super public class TestOnlyInfiniteLoops
{
    public Method "<init>":"()V"
    stack 2 locals 1
    {
        aload_0;
        invokespecial  Method java/lang/Object."<init>":"()V";
        return;
    }

    static Method test_simple:"(III)I"
    stack 200 locals 10
    {
    // Nested infinite loop, where inner loop eventually
    // looses exit to outer loop. Then, the inner loop
    // floats outside the inner loop. The entry from
    // outer to inner loop now becomes an exit for the
    // outer loop, where it now enters the next loop, that
    // used to be the inner loop.
        iconst_0;
        istore     9;

        iload      0;
        ifeq LEND; // skip

    LOOP1:
        iload      1;
        ifeq LOOP1; // dominates
    LOOP2:
        // SKIP: prevent loop-exit from becoming zero-trip guard
        iload      2;
        ifeq SKIP;
        iinc       9, 1;
    SKIP:
        iload      1;
        ifeq LOOP1; // is dominated
        goto LOOP2;

    LEND:
        iload      9;
        ireturn;
    }
    static Method test_irreducible:"(IIII)V"
    stack 200 locals 200
    {
        iload_0;
        ifeq LEND; // skip

    L1:
        iload      1;
        ifgt MERGE;
    L2:
        iload      2;
        ifge MERGE;
        goto L1;

    MERGE:
        nop;
    LOOP:
        iload      3;
        ifle L2;
        iconst_0; // always true
        ifeq LOOP;
        iconst_0; // always true
        ifeq LOOP;
    INFTY:
        goto INFTY; // infinite loop

    LEND:
        return;
    }
}