Example usage for org.eclipse.jdt.internal.compiler.codegen Opcodes OPC_aload

Introduction

In this page you can find the example usage for org.eclipse.jdt.internal.compiler.codegen Opcodes OPC_aload_0.

Prototype

byte OPC_aload_0

To view the source code for org.eclipse.jdt.internal.compiler.codegen Opcodes OPC_aload_0.

Click Source Link

Usage

From source file:org.eclipse.objectteams.otdt.internal.core.compiler.bytecode.BytecodeTransformer.java

License:Open Source License

/** Look for the nop pattern of a local var that is used to
  *  prepare for lifting. If the pattern is found, patch all those
  *  opcodes, that are constant (see class comment in Lifting).
 *///from   w  ww .  ja va2 s .co m
private int checkPatchLiftingNops(byte[] code, int idx) {
    int i;

    // Expecting 6 nops:
    for (i = idx + 1; i < idx + 6; i++)
        if (code[i] != Opcodes.OPC_nop)
            return -1;

    // Expecting aload_<loadPos>:
    int loadPos = OTByteCodes.getAloadPos(code[idx + 6], code[idx + 7]);
    if (loadPos == -1)
        return -1;
    int storeStart = (loadPos > 3) ? 8 : 7; // depends on space for pos operand

    // Expecting 3 nops:
    for (i = idx + storeStart; i < idx + storeStart + 3; i++)
        if (code[i] != Opcodes.OPC_nop)
            return -1;

    // Expecting astore_<storePos>:
    int storePos = OTByteCodes.getAstorePos(code[idx + 10], code[idx + 11]);
    if (storePos == -1)
        return -1;

    // Full match, start patching:

    // patching 6 nops:
    code[idx + 0] = Opcodes.OPC_aload_0;
    code[idx + 1] = Opcodes.OPC_invokevirtual;
    //  [idx+2/3]: space for "_OT$initCaches"
    code[idx + 4] = Opcodes.OPC_pop;

    code[idx + 5] = Opcodes.OPC_aload_0;

    // leave aload<loadPos>
    if (loadPos > 3)
        idx++;

    // patching 3 nops:
    code[idx + 7] = Opcodes.OPC_invokevirtual;
    //  [idx+8/9]: space for _OT$liftTo<Role>

    // leave astore<storePos>
    if (storePos > 3)
        loadPos += 0x2000; // flag to client that longer byte code is used
    return loadPos;
}

Example usage for org.eclipse.jdt.internal.compiler.codegen Opcodes OPC_aload_0

Introduction

Prototype

Usage