1 /*
2 * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 package jdk.tools.jaotc;
25
26 import java.util.ArrayList;
27
28 import jdk.tools.jaotc.binformat.BinaryContainer;
29 import jdk.tools.jaotc.binformat.CodeContainer;
30 import jdk.tools.jaotc.binformat.Symbol;
31 import jdk.tools.jaotc.StubInformation;
32 import org.graalvm.compiler.code.CompilationResult;
33 import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage;
34
35 import jdk.vm.ci.aarch64.AArch64;
36 import jdk.vm.ci.amd64.AMD64;
37 import jdk.vm.ci.code.TargetDescription;
38 import jdk.vm.ci.code.site.Call;
39 import jdk.vm.ci.code.site.Infopoint;
40 import jdk.vm.ci.code.site.InfopointReason;
41 import jdk.vm.ci.meta.ResolvedJavaMethod;
42
43 final class CodeSectionProcessor {
44
45 private final TargetDescription target;
46
47 private final BinaryContainer binaryContainer;
48
49 CodeSectionProcessor(DataBuilder dataBuilder) {
50 this.target = dataBuilder.getBackend().getTarget();
51 this.binaryContainer = dataBuilder.getBinaryContainer();
52 }
53
54 /**
55 * Method that looks at code section of a compiled result {@code compClass} and records function
56 * entry point symbols along with the text section contents. Note that the text section contents
57 * are not yet ready to be written in the form of a binary text section since the contents may
58 * need to be patched with references to other sections.
59 *
60 * @param compClass Graal compilation result.
61 */
62 void process(AOTCompiledClass compClass) {
63 ArrayList<CompiledMethodInfo> compiledMethods = compClass.getCompiledMethods();
64
65 for (CompiledMethodInfo methodInfo : compiledMethods) {
66 CompilationResult compResult = methodInfo.getCompilationResult();
67
68 byte[] targetCode = compResult.getTargetCode();
69 int targetCodeSize = compResult.getTargetCodeSize();
70 JavaMethodInfo compMethod = methodInfo.getMethodInfo();
71
72 // Step through all foreign calls, for every call, clear destination.
73 // Otherwise libelf may not patch them correctly.
74 for (Infopoint infopoint : compResult.getInfopoints()) {
75 if (infopoint.reason == InfopointReason.CALL) {
76 final Call callInfopoint = (Call) infopoint;
77 if (callInfopoint.target instanceof HotSpotForeignCallLinkage &&
78 target.arch instanceof AMD64) {
79 // TODO 4 is x86 size of relative displacement.
80 // For SPARC need something different.
81 int destOffset = infopoint.pcOffset + callInfopoint.size - 4;
82 targetCode[destOffset + 0] = 0;
83 targetCode[destOffset + 1] = 0;
84 targetCode[destOffset + 2] = 0;
85 targetCode[destOffset + 3] = 0;
86 }
87 }
88 }
89
90 String entry = compMethod.getSymbolName();
91 assert entry != null : "missing name for compiled method";
92
93 // Align and pad method entry
94 CodeContainer codeSection = binaryContainer.getCodeContainer();
95 int codeIdOffset = BinaryContainer.alignUp(codeSection, binaryContainer.getCodeSegmentSize());
96 // Store CodeId into code. It will be use by find_aot() using code.segments
97 methodInfo.setCodeId();
98 binaryContainer.appendIntToCode(methodInfo.getCodeId());
99 int textBaseOffset = BinaryContainer.alignUp(codeSection, binaryContainer.getCodeEntryAlignment());
100
101 codeSection.createSymbol(textBaseOffset, Symbol.Kind.JAVA_FUNCTION, Symbol.Binding.LOCAL, targetCodeSize, entry);
102
103 // Set the offset at which the text section of this method would be layed out
104 methodInfo.setTextSectionOffset(textBaseOffset);
105
106 // Write code bytes of the current method into byte stream
107 binaryContainer.appendCodeBytes(targetCode, 0, targetCodeSize);
108 int currentStubOffset = BinaryContainer.alignUp(codeSection, 8);
109 // Set the offset at which stubs of this method would be laid out
110 methodInfo.setStubsOffset(currentStubOffset - textBaseOffset);
111 // step through all calls, for every call, add a stub
112 for (Infopoint infopoint : compResult.getInfopoints()) {
113 if (infopoint.reason == InfopointReason.CALL) {
114 final Call callInfopoint = (Call) infopoint;
115 if (callInfopoint.target instanceof ResolvedJavaMethod) {
116 ResolvedJavaMethod call = (ResolvedJavaMethod) callInfopoint.target;
117 StubInformation stub = addCallStub(CallInfo.isVirtualCall(methodInfo, callInfopoint));
118 // Get the targetSymbol. A symbol for this will be created later during plt
119 // creation
120 String targetSymbol = JavaMethodInfo.uniqueMethodName(call) + ".at." + infopoint.pcOffset;
121 methodInfo.addStubCode(targetSymbol, stub);
122 currentStubOffset += stub.getSize();
123 }
124 }
125 }
126 assert currentStubOffset == codeSection.getByteStreamSize() : "wrong offset";
127 binaryContainer.addCodeSegments(codeIdOffset, currentStubOffset);
128 }
129 }
130
131 private StubInformation addCallStub(boolean isVirtualCall) {
132 final int startOffset = binaryContainer.getCodeContainer().getByteStreamSize();
133 StubInformation stub = new StubInformation(startOffset, isVirtualCall);
134 ELFMacroAssembler masm = ELFMacroAssembler.getELFMacroAssembler(target);
135 byte[] code;
136 if (isVirtualCall) {
137 code = masm.getPLTVirtualEntryCode(stub);
138 } else {
139 code = masm.getPLTStaticEntryCode(stub);
140 }
141 binaryContainer.appendCodeBytes(code, 0, code.length);
142 return stub;
143 }
144
145 }