1 /*
2 * Copyright (c) 2013, 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.lir.sparc;
26
27 import static jdk.vm.ci.code.ValueUtil.asRegister;
28 import static jdk.vm.ci.sparc.SPARC.g0;
29 import static jdk.vm.ci.sparc.SPARCKind.WORD;
30 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.BPCC;
31 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.Annul.ANNUL;
32 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.Annul.NOT_ANNUL;
33 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.BranchPredict.PREDICT_NOT_TAKEN;
34 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.BranchPredict.PREDICT_TAKEN;
35 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.CC.Xcc;
36 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.ConditionFlag.Equal;
37 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.ConditionFlag.Less;
38 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.ConditionFlag.NotEqual;
39 import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.REG;
40
41 import org.graalvm.compiler.asm.Label;
42 import org.graalvm.compiler.asm.sparc.SPARCAddress;
43 import org.graalvm.compiler.asm.sparc.SPARCMacroAssembler;
44 import org.graalvm.compiler.core.common.LIRKind;
45 import org.graalvm.compiler.lir.LIRInstructionClass;
46 import org.graalvm.compiler.lir.Opcode;
47 import org.graalvm.compiler.lir.asm.CompilationResultBuilder;
48 import org.graalvm.compiler.lir.gen.LIRGeneratorTool;
49
50 import jdk.vm.ci.code.Register;
51 import jdk.vm.ci.meta.AllocatableValue;
52 import jdk.vm.ci.meta.JavaKind;
53 import jdk.vm.ci.sparc.SPARCKind;
54
55 /**
56 * Emits code which compares two arrays of the same length.
57 */
58 @Opcode("ARRAY_EQUALS")
59 public final class SPARCArrayEqualsOp extends SPARCLIRInstruction {
60 public static final LIRInstructionClass<SPARCArrayEqualsOp> TYPE = LIRInstructionClass.create(SPARCArrayEqualsOp.class);
61 public static final SizeEstimate SIZE = SizeEstimate.create(32);
62
63 private final JavaKind kind;
64 private final int arrayBaseOffset;
65 private final int arrayIndexScale;
66
67 @Def({REG}) protected AllocatableValue resultValue;
68 @Alive({REG}) protected AllocatableValue array1Value;
69 @Alive({REG}) protected AllocatableValue array2Value;
70 @Alive({REG}) protected AllocatableValue lengthValue;
71 @Temp({REG}) protected AllocatableValue temp1;
72 @Temp({REG}) protected AllocatableValue temp2;
73 @Temp({REG}) protected AllocatableValue temp3;
74 @Temp({REG}) protected AllocatableValue temp4;
75 @Temp({REG}) protected AllocatableValue temp5;
76
77 public SPARCArrayEqualsOp(LIRGeneratorTool tool, JavaKind kind, AllocatableValue result, AllocatableValue array1, AllocatableValue array2, AllocatableValue length, boolean directPointers) {
78 super(TYPE, SIZE);
79
80 assert !kind.isNumericFloat() : "Float arrays comparison (bitwise_equal || both_NaN) isn't supported";
81 this.kind = kind;
82
83 this.arrayBaseOffset = directPointers ? 0 : tool.getProviders().getMetaAccess().getArrayBaseOffset(kind);
84 this.arrayIndexScale = tool.getProviders().getMetaAccess().getArrayIndexScale(kind);
85
86 this.resultValue = result;
87 this.array1Value = array1;
88 this.array2Value = array2;
89 this.lengthValue = length;
90
91 // Allocate some temporaries.
92 this.temp1 = tool.newVariable(LIRKind.unknownReference(tool.target().arch.getWordKind()));
93 this.temp2 = tool.newVariable(LIRKind.unknownReference(tool.target().arch.getWordKind()));
94 this.temp3 = tool.newVariable(LIRKind.value(tool.target().arch.getWordKind()));
95 this.temp4 = tool.newVariable(LIRKind.value(tool.target().arch.getWordKind()));
96 this.temp5 = tool.newVariable(LIRKind.value(tool.target().arch.getWordKind()));
97 }
98
99 @Override
100 public void emitCode(CompilationResultBuilder crb, SPARCMacroAssembler masm) {
101 Register result = asRegister(resultValue);
102 Register array1 = asRegister(temp1);
103 Register array2 = asRegister(temp2);
104 Register length = asRegister(temp3);
105
106 Label trueLabel = new Label();
107 Label falseLabel = new Label();
108 Label done = new Label();
109
110 // Load array base addresses.
111 masm.add(asRegister(array1Value), arrayBaseOffset, array1);
112 masm.add(asRegister(array2Value), arrayBaseOffset, array2);
113
114 // Get array length in bytes.
115 masm.mulx(asRegister(lengthValue, WORD), arrayIndexScale, length);
116 masm.mov(length, result); // copy
117
118 emit8ByteCompare(masm, result, array1, array2, length, trueLabel, falseLabel);
119 emitTailCompares(masm, result, array1, array2, trueLabel, falseLabel);
120
121 // Return true
122 masm.bind(trueLabel);
123 masm.mov(1, result);
124 masm.jmp(done);
125
126 // Return false
127 masm.bind(falseLabel);
128 masm.mov(g0, result);
129
130 // That's it
131 masm.bind(done);
132 }
133
134 /**
135 * Vector size used in {@link #emit8ByteCompare}.
136 */
137 private static final int VECTOR_SIZE = 8;
138
139 /**
140 * Emits code that uses 8-byte vector compares.
141 */
142 private void emit8ByteCompare(SPARCMacroAssembler masm, Register result, Register array1, Register array2, Register length, Label trueLabel, Label falseLabel) {
143 assert lengthValue.getPlatformKind().equals(SPARCKind.WORD);
144 Label loop = new Label();
145 Label compareTail = new Label();
146 Label compareTailCorrectVectorEnd = new Label();
147
148 Register tempReg1 = asRegister(temp4);
149 Register tempReg2 = asRegister(temp5);
150
151 masm.sra(length, 0, length);
152 masm.and(result, VECTOR_SIZE - 1, result); // tail count (in bytes)
153 masm.andcc(length, ~(VECTOR_SIZE - 1), length); // vector count (in bytes)
154 BPCC.emit(masm, Xcc, Equal, NOT_ANNUL, PREDICT_NOT_TAKEN, compareTail);
155
156 masm.sub(length, VECTOR_SIZE, length); // Delay slot
157 masm.add(array1, length, array1);
158 masm.add(array2, length, array2);
159 masm.sub(g0, length, length);
160
161 // Compare the last element first
162 masm.ldx(new SPARCAddress(array1, 0), tempReg1);
163 masm.ldx(new SPARCAddress(array2, 0), tempReg2);
164 masm.compareBranch(tempReg1, tempReg2, NotEqual, Xcc, falseLabel, PREDICT_NOT_TAKEN, null);
165 masm.compareBranch(length, 0, Equal, Xcc, compareTailCorrectVectorEnd, PREDICT_NOT_TAKEN, null);
166
167 // Load the first value from array 1 (Later done in back branch delay-slot)
168 masm.ldx(new SPARCAddress(array1, length), tempReg1);
169 masm.bind(loop);
170 masm.ldx(new SPARCAddress(array2, length), tempReg2);
171 masm.cmp(tempReg1, tempReg2);
172
173 BPCC.emit(masm, Xcc, NotEqual, NOT_ANNUL, PREDICT_NOT_TAKEN, falseLabel);
174 // Delay slot, not annul, add for next iteration
175 masm.addcc(length, VECTOR_SIZE, length);
176 // Annul, to prevent access past the array
177 BPCC.emit(masm, Xcc, NotEqual, ANNUL, PREDICT_TAKEN, loop);
178 masm.ldx(new SPARCAddress(array1, length), tempReg1); // Load in delay slot
179
180 // Tail count zero, therefore we can go to the end
181 masm.compareBranch(result, 0, Equal, Xcc, trueLabel, PREDICT_TAKEN, null);
182
183 masm.bind(compareTailCorrectVectorEnd);
184 // Correct the array pointers
185 masm.add(array1, VECTOR_SIZE, array1);
186 masm.add(array2, VECTOR_SIZE, array2);
187
188 masm.bind(compareTail);
189 }
190
191 /**
192 * Emits code to compare the remaining 1 to 4 bytes.
193 */
194 private void emitTailCompares(SPARCMacroAssembler masm, Register result, Register array1, Register array2, Label trueLabel, Label falseLabel) {
195 Label compare2Bytes = new Label();
196 Label compare1Byte = new Label();
197
198 Register tempReg1 = asRegister(temp3);
199 Register tempReg2 = asRegister(temp4);
200
201 if (kind.getByteCount() <= 4) {
202 // Compare trailing 4 bytes, if any.
203 masm.compareBranch(result, 4, Less, Xcc, compare2Bytes, PREDICT_NOT_TAKEN, null);
204
205 masm.lduw(new SPARCAddress(array1, 0), tempReg1);
206 masm.lduw(new SPARCAddress(array2, 0), tempReg2);
207 masm.compareBranch(tempReg1, tempReg2, NotEqual, Xcc, falseLabel, PREDICT_NOT_TAKEN, null);
208
209 if (kind.getByteCount() <= 2) {
210 // Move array pointers forward.
211 masm.add(array1, 4, array1);
212 masm.add(array2, 4, array2);
213 masm.sub(result, 4, result);
214
215 // Compare trailing 2 bytes, if any.
216 masm.bind(compare2Bytes);
217
218 masm.compareBranch(result, 2, Less, Xcc, compare1Byte, PREDICT_TAKEN, null);
219
220 masm.lduh(new SPARCAddress(array1, 0), tempReg1);
221 masm.lduh(new SPARCAddress(array2, 0), tempReg2);
222
223 masm.compareBranch(tempReg1, tempReg2, NotEqual, Xcc, falseLabel, PREDICT_TAKEN, null);
224
225 // The one-byte tail compare is only required for boolean and byte arrays.
226 if (kind.getByteCount() <= 1) {
227 // Move array pointers forward before we compare the last trailing byte.
228 masm.add(array1, 2, array1);
229 masm.add(array2, 2, array2);
230 masm.sub(result, 2, result);
231
232 // Compare trailing byte, if any.
233 masm.bind(compare1Byte);
234 masm.compareBranch(result, 1, NotEqual, Xcc, trueLabel, PREDICT_TAKEN, null);
235
236 masm.ldub(new SPARCAddress(array1, 0), tempReg1);
237 masm.ldub(new SPARCAddress(array2, 0), tempReg2);
238 masm.compareBranch(tempReg1, tempReg2, NotEqual, Xcc, falseLabel, PREDICT_TAKEN, null);
239 } else {
240 masm.bind(compare1Byte);
241 }
242 } else {
243 masm.bind(compare2Bytes);
244 }
245 }
246 }
247 }