1 /*
2 * Copyright (c) 2009, 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
25 package org.graalvm.compiler.nodes.calc;
26
27 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_1;
28 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_1;
29
30 import java.io.Serializable;
31 import java.util.function.Function;
32
33 import org.graalvm.compiler.core.common.type.ArithmeticOpTable;
34 import org.graalvm.compiler.core.common.type.ArithmeticOpTable.BinaryOp;
35 import org.graalvm.compiler.core.common.type.IntegerStamp;
36 import org.graalvm.compiler.core.common.type.Stamp;
37 import org.graalvm.compiler.debug.GraalError;
38 import org.graalvm.compiler.graph.Graph;
39 import org.graalvm.compiler.graph.Node;
40 import org.graalvm.compiler.graph.NodeClass;
41 import org.graalvm.compiler.graph.iterators.NodePredicate;
42 import org.graalvm.compiler.graph.spi.Canonicalizable;
43 import org.graalvm.compiler.graph.spi.CanonicalizerTool;
44 import org.graalvm.compiler.nodeinfo.NodeInfo;
45 import org.graalvm.compiler.nodes.ArithmeticOperation;
46 import org.graalvm.compiler.nodes.ConstantNode;
47 import org.graalvm.compiler.nodes.NodeView;
48 import org.graalvm.compiler.nodes.StructuredGraph;
49 import org.graalvm.compiler.nodes.ValueNode;
50 import org.graalvm.compiler.nodes.ValuePhiNode;
51 import org.graalvm.compiler.nodes.spi.ArithmeticLIRLowerable;
52 import org.graalvm.compiler.nodes.spi.NodeValueMap;
53
54 import jdk.vm.ci.meta.Constant;
55
56 @NodeInfo(cycles = CYCLES_1, size = SIZE_1)
57 public abstract class BinaryArithmeticNode<OP> extends BinaryNode implements ArithmeticOperation, ArithmeticLIRLowerable, Canonicalizable.Binary<ValueNode> {
58
59 @SuppressWarnings("rawtypes") public static final NodeClass<BinaryArithmeticNode> TYPE = NodeClass.create(BinaryArithmeticNode.class);
60
61 protected interface SerializableBinaryFunction<T> extends Function<ArithmeticOpTable, BinaryOp<T>>, Serializable {
62 }
63
64 protected final SerializableBinaryFunction<OP> getOp;
65
66 protected BinaryArithmeticNode(NodeClass<? extends BinaryArithmeticNode<OP>> c, SerializableBinaryFunction<OP> getOp, ValueNode x, ValueNode y) {
67 super(c, getOp.apply(ArithmeticOpTable.forStamp(x.stamp(NodeView.DEFAULT))).foldStamp(x.stamp(NodeView.DEFAULT), y.stamp(NodeView.DEFAULT)), x, y);
68 this.getOp = getOp;
69 }
70
71 protected final BinaryOp<OP> getOp(ValueNode forX, ValueNode forY) {
72 ArithmeticOpTable table = ArithmeticOpTable.forStamp(forX.stamp(NodeView.DEFAULT));
73 assert table.equals(ArithmeticOpTable.forStamp(forY.stamp(NodeView.DEFAULT)));
74 return getOp.apply(table);
75 }
76
77 @Override
78 public final BinaryOp<OP> getArithmeticOp() {
79 return getOp(getX(), getY());
80 }
81
82 public boolean isAssociative() {
83 return getArithmeticOp().isAssociative();
84 }
85
86 @Override
87 public ValueNode canonical(CanonicalizerTool tool, ValueNode forX, ValueNode forY) {
88 NodeView view = NodeView.from(tool);
89 ValueNode result = tryConstantFold(getOp(forX, forY), forX, forY, stamp(view), view);
90 if (result != null) {
91 return result;
92 }
93 if (forX instanceof ConditionalNode && forY.isConstant() && forX.hasExactlyOneUsage()) {
94 ConditionalNode conditionalNode = (ConditionalNode) forX;
95 BinaryOp<OP> arithmeticOp = getArithmeticOp();
96 ConstantNode trueConstant = tryConstantFold(arithmeticOp, conditionalNode.trueValue(), forY, this.stamp(view), view);
97 if (trueConstant != null) {
98 ConstantNode falseConstant = tryConstantFold(arithmeticOp, conditionalNode.falseValue(), forY, this.stamp(view), view);
99 if (falseConstant != null) {
100 // @formatter:off
101 /* The arithmetic is folded into a constant on both sides of the conditional.
102 * Example:
103 * (cond ? -5 : 5) + 100
104 * canonicalizes to:
105 * (cond ? 95 : 105)
106 */
107 // @formatter:on
108 return ConditionalNode.create(conditionalNode.condition, trueConstant,
109 falseConstant, view);
110 }
111 }
112 }
113 return this;
114 }
115
116 @SuppressWarnings("unused")
117 public static <OP> ConstantNode tryConstantFold(BinaryOp<OP> op, ValueNode forX, ValueNode forY, Stamp stamp, NodeView view) {
118 if (forX.isConstant() && forY.isConstant()) {
119 Constant ret = op.foldConstant(forX.asConstant(), forY.asConstant());
120 if (ret != null) {
121 return ConstantNode.forPrimitive(stamp, ret);
122 }
123 }
124 return null;
125 }
126
127 @Override
128 public Stamp foldStamp(Stamp stampX, Stamp stampY) {
129 assert stampX.isCompatible(x.stamp(NodeView.DEFAULT)) && stampY.isCompatible(y.stamp(NodeView.DEFAULT));
130 return getArithmeticOp().foldStamp(stampX, stampY);
131 }
132
133 public static ValueNode add(StructuredGraph graph, ValueNode v1, ValueNode v2, NodeView view) {
134 return graph.addOrUniqueWithInputs(AddNode.create(v1, v2, view));
135 }
136
137 public static ValueNode add(ValueNode v1, ValueNode v2, NodeView view) {
138 return AddNode.create(v1, v2, view);
139 }
140
141 public static ValueNode add(ValueNode v1, ValueNode v2) {
142 return add(v1, v2, NodeView.DEFAULT);
143 }
144
145 public static ValueNode mul(StructuredGraph graph, ValueNode v1, ValueNode v2, NodeView view) {
146 return graph.addOrUniqueWithInputs(MulNode.create(v1, v2, view));
147 }
148
149 public static ValueNode mul(ValueNode v1, ValueNode v2, NodeView view) {
150 return MulNode.create(v1, v2, view);
151 }
152
153 public static ValueNode mul(ValueNode v1, ValueNode v2) {
154 return mul(v1, v2, NodeView.DEFAULT);
155 }
156
157 public static ValueNode sub(StructuredGraph graph, ValueNode v1, ValueNode v2, NodeView view) {
158 return graph.addOrUniqueWithInputs(SubNode.create(v1, v2, view));
159 }
160
161 public static ValueNode sub(ValueNode v1, ValueNode v2, NodeView view) {
162 return SubNode.create(v1, v2, view);
163 }
164
165 public static ValueNode sub(ValueNode v1, ValueNode v2) {
166 return sub(v1, v2, NodeView.DEFAULT);
167 }
168
169 public static ValueNode branchlessMin(ValueNode v1, ValueNode v2, NodeView view) {
170 if (v1.isDefaultConstant() && !v2.isDefaultConstant()) {
171 return branchlessMin(v2, v1, view);
172 }
173 int bits = ((IntegerStamp) v1.stamp(view)).getBits();
174 assert ((IntegerStamp) v2.stamp(view)).getBits() == bits;
175 ValueNode t1 = sub(v1, v2, view);
176 ValueNode t2 = RightShiftNode.create(t1, bits - 1, view);
177 ValueNode t3 = AndNode.create(t1, t2, view);
178 return add(v2, t3, view);
179 }
180
181 public static ValueNode branchlessMax(ValueNode v1, ValueNode v2, NodeView view) {
182 if (v1.isDefaultConstant() && !v2.isDefaultConstant()) {
183 return branchlessMax(v2, v1, view);
184 }
185 int bits = ((IntegerStamp) v1.stamp(view)).getBits();
186 assert ((IntegerStamp) v2.stamp(view)).getBits() == bits;
187 if (v2.isDefaultConstant()) {
188 // prefer a & ~(a>>31) to a - (a & (a>>31))
189 return AndNode.create(v1, NotNode.create(RightShiftNode.create(v1, bits - 1, view)), view);
190 } else {
191 ValueNode t1 = sub(v1, v2, view);
192 ValueNode t2 = RightShiftNode.create(t1, bits - 1, view);
193 ValueNode t3 = AndNode.create(t1, t2, view);
194 return sub(v1, t3, view);
195 }
196 }
197
198 private enum ReassociateMatch {
199 x,
200 y;
201
202 public ValueNode getValue(BinaryNode binary) {
203 switch (this) {
204 case x:
205 return binary.getX();
206 case y:
207 return binary.getY();
208 default:
209 throw GraalError.shouldNotReachHere();
210 }
211 }
212
213 public ValueNode getOtherValue(BinaryNode binary) {
214 switch (this) {
215 case x:
216 return binary.getY();
217 case y:
218 return binary.getX();
219 default:
220 throw GraalError.shouldNotReachHere();
221 }
222 }
223 }
224
225 private static ReassociateMatch findReassociate(BinaryNode binary, NodePredicate criterion) {
226 boolean resultX = criterion.apply(binary.getX());
227 boolean resultY = criterion.apply(binary.getY());
228 if (resultX && !resultY) {
229 return ReassociateMatch.x;
230 }
231 if (!resultX && resultY) {
232 return ReassociateMatch.y;
233 }
234 return null;
235 }
236
237 //@formatter:off
238 /*
239 * In reassociate, complexity comes from the handling of IntegerSub (non commutative) which can
240 * be mixed with IntegerAdd. It first tries to find m1, m2 which match the criterion :
241 * (a o m2) o m1
242 * (m2 o a) o m1
243 * m1 o (a o m2)
244 * m1 o (m2 o a)
245 * It then produces 4 boolean for the -/+ cases:
246 * invertA : should the final expression be like *-a (rather than a+*)
247 * aSub : should the final expression be like a-* (rather than a+*)
248 * invertM1 : should the final expression contain -m1
249 * invertM2 : should the final expression contain -m2
250 *
251 */
252 //@formatter:on
253 /**
254 * Tries to re-associate values which satisfy the criterion. For example with a constantness
255 * criterion: {@code (a + 2) + 1 => a + (1 + 2)}
256 * <p>
257 * This method accepts only {@linkplain BinaryOp#isAssociative() associative} operations such as
258 * +, -, *, &, | and ^
259 *
260 * @param forY
261 * @param forX
262 */
263 public static ValueNode reassociate(BinaryArithmeticNode<?> node, NodePredicate criterion, ValueNode forX, ValueNode forY, NodeView view) {
264 assert node.getOp(forX, forY).isAssociative();
265 ReassociateMatch match1 = findReassociate(node, criterion);
266 if (match1 == null) {
267 return node;
268 }
269 ValueNode otherValue = match1.getOtherValue(node);
270 boolean addSub = false;
271 boolean subAdd = false;
272 if (otherValue.getClass() != node.getClass()) {
273 if (node instanceof AddNode && otherValue instanceof SubNode) {
274 addSub = true;
275 } else if (node instanceof SubNode && otherValue instanceof AddNode) {
276 subAdd = true;
277 } else {
278 return node;
279 }
280 }
281 BinaryNode other = (BinaryNode) otherValue;
282 ReassociateMatch match2 = findReassociate(other, criterion);
283 if (match2 == null) {
284 return node;
285 }
286 boolean invertA = false;
287 boolean aSub = false;
288 boolean invertM1 = false;
289 boolean invertM2 = false;
290 if (addSub) {
291 invertM2 = match2 == ReassociateMatch.y;
292 invertA = !invertM2;
293 } else if (subAdd) {
294 invertA = invertM2 = match1 == ReassociateMatch.x;
295 invertM1 = !invertM2;
296 } else if (node instanceof SubNode && other instanceof SubNode) {
297 invertA = match1 == ReassociateMatch.x ^ match2 == ReassociateMatch.x;
298 aSub = match1 == ReassociateMatch.y && match2 == ReassociateMatch.y;
299 invertM1 = match1 == ReassociateMatch.y && match2 == ReassociateMatch.x;
300 invertM2 = match1 == ReassociateMatch.x && match2 == ReassociateMatch.x;
301 }
302 assert !(invertM1 && invertM2) && !(invertA && aSub);
303 ValueNode m1 = match1.getValue(node);
304 ValueNode m2 = match2.getValue(other);
305 ValueNode a = match2.getOtherValue(other);
306 if (node instanceof AddNode || node instanceof SubNode) {
307 ValueNode associated;
308 if (invertM1) {
309 associated = BinaryArithmeticNode.sub(m2, m1, view);
310 } else if (invertM2) {
311 associated = BinaryArithmeticNode.sub(m1, m2, view);
312 } else {
313 associated = BinaryArithmeticNode.add(m1, m2, view);
314 }
315 if (invertA) {
316 return BinaryArithmeticNode.sub(associated, a, view);
317 }
318 if (aSub) {
319 return BinaryArithmeticNode.sub(a, associated, view);
320 }
321 return BinaryArithmeticNode.add(a, associated, view);
322 } else if (node instanceof MulNode) {
323 return BinaryArithmeticNode.mul(a, AddNode.mul(m1, m2, view), view);
324 } else if (node instanceof AndNode) {
325 return new AndNode(a, new AndNode(m1, m2));
326 } else if (node instanceof OrNode) {
327 return new OrNode(a, new OrNode(m1, m2));
328 } else if (node instanceof XorNode) {
329 return new XorNode(a, new XorNode(m1, m2));
330 } else {
331 throw GraalError.shouldNotReachHere();
332 }
333 }
334
335 /**
336 * Ensure a canonical ordering of inputs for commutative nodes to improve GVN results. Order the
337 * inputs by increasing {@link Node#id} and call {@link Graph#findDuplicate(Node)} on the node
338 * if it's currently in a graph. It's assumed that if there was a constant on the left it's been
339 * moved to the right by other code and that ordering is left alone.
340 *
341 * @return the original node or another node with the same input ordering
342 */
343 @SuppressWarnings("deprecation")
344 public BinaryNode maybeCommuteInputs() {
345 assert this instanceof BinaryCommutative;
346 if (!y.isConstant() && (x.isConstant() || x.getId() > y.getId())) {
347 ValueNode tmp = x;
348 x = y;
349 y = tmp;
350 if (graph() != null) {
351 // See if this node already exists
352 BinaryNode duplicate = graph().findDuplicate(this);
353 if (duplicate != null) {
354 return duplicate;
355 }
356 }
357 }
358 return this;
359 }
360
361 /**
362 * Determines if it would be better to swap the inputs in order to produce better assembly code.
363 * First we try to pick a value which is dead after this use. If both values are dead at this
364 * use then we try pick an induction variable phi to encourage the phi to live in a single
365 * register.
366 *
367 * @param nodeValueMap
368 * @return true if inputs should be swapped, false otherwise
369 */
370 protected boolean shouldSwapInputs(NodeValueMap nodeValueMap) {
371 final boolean xHasOtherUsages = getX().hasUsagesOtherThan(this, nodeValueMap);
372 final boolean yHasOtherUsages = getY().hasUsagesOtherThan(this, nodeValueMap);
373
374 if (!getY().isConstant() && !yHasOtherUsages) {
375 if (xHasOtherUsages == yHasOtherUsages) {
376 return getY() instanceof ValuePhiNode && getY().inputs().contains(this);
377 } else {
378 return true;
379 }
380 }
381 return false;
382 }
383
384 }