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