01: /*
02: * Copyright 2001 Sun Microsystems, Inc. All Rights Reserved.
03: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
04: *
05: * This code is free software; you can redistribute it and/or modify it
06: * under the terms of the GNU General Public License version 2 only, as
07: * published by the Free Software Foundation. Sun designates this
08: * particular file as subject to the "Classpath" exception as provided
09: * by Sun in the LICENSE file that accompanied this code.
10: *
11: * This code is distributed in the hope that it will be useful, but WITHOUT
12: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14: * version 2 for more details (a copy is included in the LICENSE file that
15: * accompanied this code).
16: *
17: * You should have received a copy of the GNU General Public License version
18: * 2 along with this work; if not, write to the Free Software Foundation,
19: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20: *
21: * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22: * CA 95054 USA or visit www.sun.com if you need additional information or
23: * have any questions.
24: */
25:
26: package sun.reflect;
27:
28: import java.util.Iterator;
29: import java.util.List;
30: import java.util.ArrayList;
31:
32: /** Allows forward references in bytecode streams emitted by
33: ClassFileAssembler. Assumes that the start of the method body is
34: the first byte in the assembler's buffer. May be used at more than
35: one branch site. */
36:
37: class Label {
38: static class PatchInfo {
39: PatchInfo(ClassFileAssembler asm, short instrBCI,
40: short patchBCI, int stackDepth) {
41: this .asm = asm;
42: this .instrBCI = instrBCI;
43: this .patchBCI = patchBCI;
44: this .stackDepth = stackDepth;
45: }
46:
47: // This won't work for more than one assembler anyway, so this is
48: // unnecessary
49: ClassFileAssembler asm;
50: short instrBCI;
51: short patchBCI;
52: int stackDepth;
53: }
54:
55: private List/*<PatchInfo>*/patches = new ArrayList();
56:
57: public Label() {
58: }
59:
60: void add(ClassFileAssembler asm, short instrBCI, short patchBCI,
61: int stackDepth) {
62: patches.add(new PatchInfo(asm, instrBCI, patchBCI, stackDepth));
63: }
64:
65: public void bind() {
66: for (Iterator iter = patches.iterator(); iter.hasNext();) {
67: PatchInfo patch = (PatchInfo) iter.next();
68: short curBCI = patch.asm.getLength();
69: short offset = (short) (curBCI - patch.instrBCI);
70: patch.asm.emitShort(patch.patchBCI, offset);
71: patch.asm.setStack(patch.stackDepth);
72: }
73: }
74: }
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