1 /*
2 * Copyright (c) 2009, 2012, 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 package org.graalvm.compiler.lir;
24
25 import java.util.ArrayList;
26 import java.util.Arrays;
27 import java.util.List;
28
29 import org.graalvm.compiler.core.common.cfg.AbstractBlockBase;
30 import org.graalvm.compiler.core.common.cfg.AbstractControlFlowGraph;
31 import org.graalvm.compiler.core.common.cfg.BlockMap;
32 import org.graalvm.compiler.debug.DebugContext;
33 import org.graalvm.compiler.lir.StandardOp.BlockEndOp;
34 import org.graalvm.compiler.lir.StandardOp.LabelOp;
35 import org.graalvm.compiler.lir.gen.LIRGenerator;
36 import org.graalvm.compiler.options.OptionValues;
37
38 /**
39 * This class implements the overall container for the LIR graph and directs its construction,
40 * optimization, and finalization.
41 */
42 public final class LIR extends LIRGenerator.VariableProvider {
43
44 private final AbstractControlFlowGraph<?> cfg;
45
46 /**
47 * The linear-scan ordered list of blocks.
48 */
49 private final AbstractBlockBase<?>[] linearScanOrder;
50
51 /**
52 * The order in which the code is emitted.
53 */
54 private final AbstractBlockBase<?>[] codeEmittingOrder;
55
56 /**
57 * Map from {@linkplain AbstractBlockBase block} to {@linkplain LIRInstruction}s. Note that we
58 * are using {@link ArrayList} instead of {@link List} to avoid interface dispatch.
59 */
60 private final BlockMap<ArrayList<LIRInstruction>> lirInstructions;
61
62 private boolean hasArgInCallerFrame;
63
64 private final OptionValues options;
65
66 private final DebugContext debug;
67
68 /**
69 * Creates a new LIR instance for the specified compilation.
70 */
71 public LIR(AbstractControlFlowGraph<?> cfg, AbstractBlockBase<?>[] linearScanOrder, AbstractBlockBase<?>[] codeEmittingOrder, OptionValues options, DebugContext debug) {
72 this.cfg = cfg;
73 this.codeEmittingOrder = codeEmittingOrder;
74 this.linearScanOrder = linearScanOrder;
75 this.lirInstructions = new BlockMap<>(cfg);
76 this.options = options;
77 this.debug = debug;
78 }
79
80 public AbstractControlFlowGraph<?> getControlFlowGraph() {
81 return cfg;
82 }
83
84 public OptionValues getOptions() {
85 return options;
86 }
87
88 public DebugContext getDebug() {
89 return debug;
90 }
91
92 /**
93 * Determines if any instruction in the LIR has debug info associated with it.
94 */
95 public boolean hasDebugInfo() {
96 for (AbstractBlockBase<?> b : linearScanOrder()) {
97 for (LIRInstruction op : getLIRforBlock(b)) {
98 if (op.hasState()) {
99 return true;
100 }
101 }
102 }
103 return false;
104 }
105
106 public ArrayList<LIRInstruction> getLIRforBlock(AbstractBlockBase<?> block) {
107 return lirInstructions.get(block);
108 }
109
110 public void setLIRforBlock(AbstractBlockBase<?> block, ArrayList<LIRInstruction> list) {
111 assert getLIRforBlock(block) == null : "lir instruction list should only be initialized once";
112 lirInstructions.put(block, list);
113 }
114
115 /**
116 * Gets the linear scan ordering of blocks as an array.
117 *
118 * @return the blocks in linear scan order
119 */
120 public AbstractBlockBase<?>[] linearScanOrder() {
121 return linearScanOrder;
122 }
123
124 public AbstractBlockBase<?>[] codeEmittingOrder() {
125 return codeEmittingOrder;
126 }
127
128 public void setHasArgInCallerFrame() {
129 hasArgInCallerFrame = true;
130 }
131
132 /**
133 * Determines if any of the parameters to the method are passed via the stack where the
134 * parameters are located in the caller's frame.
135 */
136 public boolean hasArgInCallerFrame() {
137 return hasArgInCallerFrame;
138 }
139
140 /**
141 * Gets the next non-{@code null} block in a list.
142 *
143 * @param blocks list of blocks
144 * @param blockIndex index of the current block
145 * @return the next block in the list that is none {@code null} or {@code null} if there is no
146 * such block
147 */
148 public static AbstractBlockBase<?> getNextBlock(AbstractBlockBase<?>[] blocks, int blockIndex) {
149 for (int nextIndex = blockIndex + 1; nextIndex > 0 && nextIndex < blocks.length; nextIndex++) {
150 AbstractBlockBase<?> nextBlock = blocks[nextIndex];
151 if (nextBlock != null) {
152 return nextBlock;
153 }
154 }
155 return null;
156 }
157
158 /**
159 * Gets the exception edge (if any) originating at a given operation.
160 */
161 public static LabelRef getExceptionEdge(LIRInstruction op) {
162 final LabelRef[] exceptionEdge = {null};
163 op.forEachState(state -> {
164 if (state.exceptionEdge != null) {
165 assert exceptionEdge[0] == null;
166 exceptionEdge[0] = state.exceptionEdge;
167 }
168 });
169 return exceptionEdge[0];
170 }
171
172 /**
173 * The maximum distance an operation with an {@linkplain #getExceptionEdge(LIRInstruction)
174 * exception edge} can be from the last instruction of a LIR block. The value of 3 is based on a
175 * non-void call operation that has an exception edge. Such a call may move the result to
176 * another register and then spill it.
177 * <p>
178 * The rationale for such a constant is to limit the search for an insertion point when adding
179 * move operations at the end of a block. Such moves must be inserted before all control flow
180 * instructions.
181 */
182 public static final int MAX_EXCEPTION_EDGE_OP_DISTANCE_FROM_END = 3;
183
184 public static boolean verifyBlock(LIR lir, AbstractBlockBase<?> block) {
185 ArrayList<LIRInstruction> ops = lir.getLIRforBlock(block);
186 if (ops.size() == 0) {
187 return false;
188 }
189 assert ops.get(0) instanceof LabelOp : String.format("Not a Label %s (Block %s)", ops.get(0).getClass(), block);
190 LIRInstruction opWithExceptionEdge = null;
191 int index = 0;
192 int lastIndex = ops.size() - 1;
193 for (LIRInstruction op : ops.subList(0, lastIndex)) {
194 assert !(op instanceof BlockEndOp) : String.format("BlockEndOp %s (Block %s)", op.getClass(), block);
195 LabelRef exceptionEdge = getExceptionEdge(op);
196 if (exceptionEdge != null) {
197 assert opWithExceptionEdge == null : "multiple ops with an exception edge not allowed";
198 opWithExceptionEdge = op;
199 int distanceFromEnd = lastIndex - index;
200 assert distanceFromEnd <= MAX_EXCEPTION_EDGE_OP_DISTANCE_FROM_END;
201 }
202 index++;
203 }
204 LIRInstruction end = ops.get(lastIndex);
205 assert end instanceof BlockEndOp : String.format("Not a BlockEndOp %s (Block %s)", end.getClass(), block);
206 return true;
207 }
208
209 public static boolean verifyBlocks(LIR lir, AbstractBlockBase<?>[] blocks) {
210 for (AbstractBlockBase<?> block : blocks) {
211 if (block == null) {
212 continue;
213 }
214 for (AbstractBlockBase<?> sux : block.getSuccessors()) {
215 assert Arrays.asList(blocks).contains(sux) : "missing successor from: " + block + "to: " + sux;
216 }
217 for (AbstractBlockBase<?> pred : block.getPredecessors()) {
218 assert Arrays.asList(blocks).contains(pred) : "missing predecessor from: " + block + "to: " + pred;
219 }
220 if (!verifyBlock(lir, block)) {
221 return false;
222 }
223 }
224 return true;
225 }
226
227 public void resetLabels() {
228
229 for (AbstractBlockBase<?> block : codeEmittingOrder()) {
230 if (block == null) {
231 continue;
232 }
233 for (LIRInstruction inst : lirInstructions.get(block)) {
234 if (inst instanceof LabelOp) {
235 ((LabelOp) inst).getLabel().reset();
236 }
237 }
238 }
239 }
240
241 }