1 /* 2 * Copyright (c) 2011, 2016, 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.amd64; 24 25 import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.CONST; 26 import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.HINT; 27 import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.ILLEGAL; 28 import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.REG; 29 import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.STACK; 30 import static jdk.vm.ci.code.ValueUtil.asRegister; 31 import static jdk.vm.ci.code.ValueUtil.isRegister; 32 33 import org.graalvm.compiler.asm.Label; 34 import org.graalvm.compiler.core.common.NumUtil; 35 import org.graalvm.compiler.asm.amd64.AMD64Address; 36 import org.graalvm.compiler.asm.amd64.AMD64Address.Scale; 37 import org.graalvm.compiler.asm.amd64.AMD64Assembler.ConditionFlag; 38 import org.graalvm.compiler.asm.amd64.AMD64MacroAssembler; 39 import org.graalvm.compiler.code.CompilationResult.JumpTable; 40 import org.graalvm.compiler.core.common.calc.Condition; 41 import org.graalvm.compiler.debug.GraalError; 42 import org.graalvm.compiler.lir.LIRInstructionClass; 43 import org.graalvm.compiler.lir.LabelRef; 44 import org.graalvm.compiler.lir.Opcode; 45 import org.graalvm.compiler.lir.StandardOp; 46 import org.graalvm.compiler.lir.StandardOp.BlockEndOp; 47 import org.graalvm.compiler.lir.SwitchStrategy; 48 import org.graalvm.compiler.lir.SwitchStrategy.BaseSwitchClosure; 49 import org.graalvm.compiler.lir.Variable; 50 import org.graalvm.compiler.lir.asm.CompilationResultBuilder; 51 52 import jdk.vm.ci.amd64.AMD64; 53 import jdk.vm.ci.amd64.AMD64.CPUFeature; 54 import jdk.vm.ci.amd64.AMD64Kind; 55 import jdk.vm.ci.code.Register; 56 import jdk.vm.ci.meta.AllocatableValue; 57 import jdk.vm.ci.meta.Constant; 58 import jdk.vm.ci.meta.JavaConstant; 59 import jdk.vm.ci.meta.Value; 60 61 public class AMD64ControlFlow { 62 63 public static final class ReturnOp extends AMD64BlockEndOp implements BlockEndOp { 64 public static final LIRInstructionClass<ReturnOp> TYPE = LIRInstructionClass.create(ReturnOp.class); 65 @Use({REG, ILLEGAL}) protected Value x; 66 67 public ReturnOp(Value x) { 68 super(TYPE); 69 this.x = x; 70 } 71 72 @Override 73 public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) { 74 crb.frameContext.leave(crb); 75 /* 76 * We potentially return to the interpreter, and that's an AVX-SSE transition. The only 77 * live value at this point should be the return value in either rax, or in xmm0 with 78 * the upper half of the register unused, so we don't destroy any value here. 79 */ 80 if (masm.supports(CPUFeature.AVX)) { 81 masm.vzeroupper(); 82 } 83 masm.ret(0); 84 } 85 } 86 87 public static class BranchOp extends AMD64BlockEndOp implements StandardOp.BranchOp { 88 public static final LIRInstructionClass<BranchOp> TYPE = LIRInstructionClass.create(BranchOp.class); 89 protected final ConditionFlag condition; 90 protected final LabelRef trueDestination; 91 protected final LabelRef falseDestination; 92 93 private final double trueDestinationProbability; 94 95 public BranchOp(Condition condition, LabelRef trueDestination, LabelRef falseDestination, double trueDestinationProbability) { 96 this(intCond(condition), trueDestination, falseDestination, trueDestinationProbability); 97 } 98 99 public BranchOp(ConditionFlag condition, LabelRef trueDestination, LabelRef falseDestination, double trueDestinationProbability) { 100 this(TYPE, condition, trueDestination, falseDestination, trueDestinationProbability); 101 } 102 103 protected BranchOp(LIRInstructionClass<? extends BranchOp> c, ConditionFlag condition, LabelRef trueDestination, LabelRef falseDestination, double trueDestinationProbability) { 104 super(c); 105 this.condition = condition; 106 this.trueDestination = trueDestination; 107 this.falseDestination = falseDestination; 108 this.trueDestinationProbability = trueDestinationProbability; 109 } 110 111 @Override 112 public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) { 113 boolean isNegated = false; 114 int jccPos = masm.position(); 115 /* 116 * The strategy for emitting jumps is: If either trueDestination or falseDestination is 117 * the successor block, assume the block scheduler did the correct thing and jcc to the 118 * other. Otherwise, we need a jcc followed by a jmp. Use the branch probability to make 119 * sure it is more likely to branch on the jcc (= less likely to execute both the jcc 120 * and the jmp instead of just the jcc). In the case of loops, that means the jcc is the 121 * back-edge. 122 */ 123 if (crb.isSuccessorEdge(trueDestination)) { 124 jcc(masm, true, falseDestination); 125 isNegated = true; 126 } else if (crb.isSuccessorEdge(falseDestination)) { 127 jcc(masm, false, trueDestination); 128 } else if (trueDestinationProbability < 0.5) { 129 jcc(masm, true, falseDestination); 130 masm.jmp(trueDestination.label()); 131 isNegated = true; 132 } else { 133 jcc(masm, false, trueDestination); 134 masm.jmp(falseDestination.label()); 135 } 136 crb.recordBranch(jccPos, isNegated); 137 } 138 139 protected void jcc(AMD64MacroAssembler masm, boolean negate, LabelRef target) { 140 masm.jcc(negate ? condition.negate() : condition, target.label()); 141 } 142 } 143 144 public static final class FloatBranchOp extends BranchOp { 145 public static final LIRInstructionClass<FloatBranchOp> TYPE = LIRInstructionClass.create(FloatBranchOp.class); 146 protected boolean unorderedIsTrue; 147 148 public FloatBranchOp(Condition condition, boolean unorderedIsTrue, LabelRef trueDestination, LabelRef falseDestination, double trueDestinationProbability) { 149 super(TYPE, floatCond(condition), trueDestination, falseDestination, trueDestinationProbability); 150 this.unorderedIsTrue = unorderedIsTrue; 151 } 152 153 @Override 154 protected void jcc(AMD64MacroAssembler masm, boolean negate, LabelRef target) { 155 floatJcc(masm, negate ? condition.negate() : condition, negate ? !unorderedIsTrue : unorderedIsTrue, target.label()); 156 } 157 } 158 159 public static class StrategySwitchOp extends AMD64BlockEndOp { 160 public static final LIRInstructionClass<StrategySwitchOp> TYPE = LIRInstructionClass.create(StrategySwitchOp.class); 161 protected final Constant[] keyConstants; 162 private final LabelRef[] keyTargets; 163 private LabelRef defaultTarget; 164 @Alive({REG}) protected Value key; 165 @Temp({REG, ILLEGAL}) protected Value scratch; 166 protected final SwitchStrategy strategy; 167 168 public StrategySwitchOp(SwitchStrategy strategy, LabelRef[] keyTargets, LabelRef defaultTarget, Value key, Value scratch) { 169 this(TYPE, strategy, keyTargets, defaultTarget, key, scratch); 170 } 171 172 protected StrategySwitchOp(LIRInstructionClass<? extends StrategySwitchOp> c, SwitchStrategy strategy, LabelRef[] keyTargets, LabelRef defaultTarget, Value key, Value scratch) { 173 super(c); 174 this.strategy = strategy; 175 this.keyConstants = strategy.getKeyConstants(); 176 this.keyTargets = keyTargets; 177 this.defaultTarget = defaultTarget; 178 this.key = key; 179 this.scratch = scratch; 180 assert keyConstants.length == keyTargets.length; 181 assert keyConstants.length == strategy.keyProbabilities.length; 182 } 183 184 @Override 185 public void emitCode(final CompilationResultBuilder crb, final AMD64MacroAssembler masm) { 186 strategy.run(new SwitchClosure(asRegister(key), crb, masm)); 187 } 188 189 public class SwitchClosure extends BaseSwitchClosure { 190 191 protected final Register keyRegister; 192 protected final CompilationResultBuilder crb; 193 protected final AMD64MacroAssembler masm; 194 195 protected SwitchClosure(Register keyRegister, CompilationResultBuilder crb, AMD64MacroAssembler masm) { 196 super(crb, masm, keyTargets, defaultTarget); 197 this.keyRegister = keyRegister; 198 this.crb = crb; 199 this.masm = masm; 200 } 201 202 protected void emitComparison(Constant c) { 203 JavaConstant jc = (JavaConstant) c; 204 switch (jc.getJavaKind()) { 205 case Int: 206 long lc = jc.asLong(); 207 assert NumUtil.isInt(lc); 208 masm.cmpl(keyRegister, (int) lc); 209 break; 210 case Long: 211 masm.cmpq(keyRegister, (AMD64Address) crb.asLongConstRef(jc)); 212 break; 213 case Object: 214 AMD64Move.const2reg(crb, masm, asRegister(scratch), jc); 215 masm.cmpptr(keyRegister, asRegister(scratch)); 216 break; 217 default: 218 throw new GraalError("switch only supported for int, long and object"); 219 } 220 } 221 222 @Override 223 protected void conditionalJump(int index, Condition condition, Label target) { 224 emitComparison(keyConstants[index]); 225 masm.jcc(intCond(condition), target); 226 } 227 } 228 } 229 230 public static final class TableSwitchOp extends AMD64BlockEndOp { 231 public static final LIRInstructionClass<TableSwitchOp> TYPE = LIRInstructionClass.create(TableSwitchOp.class); 232 private final int lowKey; 233 private final LabelRef defaultTarget; 234 private final LabelRef[] targets; 235 @Use protected Value index; 236 @Temp({REG, HINT}) protected Value idxScratch; 237 @Temp protected Value scratch; 238 239 public TableSwitchOp(final int lowKey, final LabelRef defaultTarget, final LabelRef[] targets, Value index, Variable scratch, Variable idxScratch) { 240 super(TYPE); 241 this.lowKey = lowKey; 242 this.defaultTarget = defaultTarget; 243 this.targets = targets; 244 this.index = index; 245 this.scratch = scratch; 246 this.idxScratch = idxScratch; 247 } 248 249 @Override 250 public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) { 251 Register indexReg = asRegister(index, AMD64Kind.DWORD); 252 Register idxScratchReg = asRegister(idxScratch, AMD64Kind.DWORD); 253 Register scratchReg = asRegister(scratch, AMD64Kind.QWORD); 254 255 if (!indexReg.equals(idxScratchReg)) { 256 masm.movl(idxScratchReg, indexReg); 257 } 258 259 // Compare index against jump table bounds 260 int highKey = lowKey + targets.length - 1; 261 if (lowKey != 0) { 262 // subtract the low value from the switch value 263 masm.subl(idxScratchReg, lowKey); 264 masm.cmpl(idxScratchReg, highKey - lowKey); 265 } else { 266 masm.cmpl(idxScratchReg, highKey); 267 } 268 269 // Jump to default target if index is not within the jump table 270 if (defaultTarget != null) { 271 masm.jcc(ConditionFlag.Above, defaultTarget.label()); 272 } 273 274 // Set scratch to address of jump table 275 masm.leaq(scratchReg, new AMD64Address(AMD64.rip, 0)); 276 final int afterLea = masm.position(); 277 278 // Load jump table entry into scratch and jump to it 279 masm.movslq(idxScratchReg, new AMD64Address(scratchReg, idxScratchReg, Scale.Times4, 0)); 280 masm.addq(scratchReg, idxScratchReg); 281 masm.jmp(scratchReg); 282 283 // Inserting padding so that jump table address is 4-byte aligned 284 if ((masm.position() & 0x3) != 0) { 285 masm.nop(4 - (masm.position() & 0x3)); 286 } 287 288 // Patch LEA instruction above now that we know the position of the jump table 289 // TODO this is ugly and should be done differently 290 final int jumpTablePos = masm.position(); 291 final int leaDisplacementPosition = afterLea - 4; 292 masm.emitInt(jumpTablePos - afterLea, leaDisplacementPosition); 293 294 // Emit jump table entries 295 for (LabelRef target : targets) { 296 Label label = target.label(); 297 int offsetToJumpTableBase = masm.position() - jumpTablePos; 298 if (label.isBound()) { 299 int imm32 = label.position() - jumpTablePos; 300 masm.emitInt(imm32); 301 } else { 302 label.addPatchAt(masm.position()); 303 304 masm.emitByte(0); // pseudo-opcode for jump table entry 305 masm.emitShort(offsetToJumpTableBase); 306 masm.emitByte(0); // padding to make jump table entry 4 bytes wide 307 } 308 } 309 310 JumpTable jt = new JumpTable(jumpTablePos, lowKey, highKey, 4); 311 crb.compilationResult.addAnnotation(jt); 312 } 313 } 314 315 @Opcode("CMOVE") 316 public static final class CondMoveOp extends AMD64LIRInstruction { 317 public static final LIRInstructionClass<CondMoveOp> TYPE = LIRInstructionClass.create(CondMoveOp.class); 318 @Def({REG, HINT}) protected Value result; 319 @Alive({REG}) protected Value trueValue; 320 @Use({REG, STACK, CONST}) protected Value falseValue; 321 private final ConditionFlag condition; 322 323 public CondMoveOp(Variable result, Condition condition, AllocatableValue trueValue, Value falseValue) { 324 super(TYPE); 325 this.result = result; 326 this.condition = intCond(condition); 327 this.trueValue = trueValue; 328 this.falseValue = falseValue; 329 } 330 331 @Override 332 public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) { 333 cmove(crb, masm, result, false, condition, false, trueValue, falseValue); 334 } 335 } 336 337 @Opcode("CMOVE") 338 public static final class FloatCondMoveOp extends AMD64LIRInstruction { 339 public static final LIRInstructionClass<FloatCondMoveOp> TYPE = LIRInstructionClass.create(FloatCondMoveOp.class); 340 @Def({REG}) protected Value result; 341 @Alive({REG}) protected Value trueValue; 342 @Alive({REG}) protected Value falseValue; 343 private final ConditionFlag condition; 344 private final boolean unorderedIsTrue; 345 346 public FloatCondMoveOp(Variable result, Condition condition, boolean unorderedIsTrue, Variable trueValue, Variable falseValue) { 347 super(TYPE); 348 this.result = result; 349 this.condition = floatCond(condition); 350 this.unorderedIsTrue = unorderedIsTrue; 351 this.trueValue = trueValue; 352 this.falseValue = falseValue; 353 } 354 355 @Override 356 public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) { 357 cmove(crb, masm, result, true, condition, unorderedIsTrue, trueValue, falseValue); 358 } 359 } 360 361 private static void floatJcc(AMD64MacroAssembler masm, ConditionFlag condition, boolean unorderedIsTrue, Label label) { 362 Label endLabel = new Label(); 363 if (unorderedIsTrue && !trueOnUnordered(condition)) { 364 masm.jcc(ConditionFlag.Parity, label); 365 } else if (!unorderedIsTrue && trueOnUnordered(condition)) { 366 masm.jccb(ConditionFlag.Parity, endLabel); 367 } 368 masm.jcc(condition, label); 369 masm.bind(endLabel); 370 } 371 372 private static void cmove(CompilationResultBuilder crb, AMD64MacroAssembler masm, Value result, boolean isFloat, ConditionFlag condition, boolean unorderedIsTrue, Value trueValue, 373 Value falseValue) { 374 // check that we don't overwrite an input operand before it is used. 375 assert !result.equals(trueValue); 376 377 AMD64Move.move(crb, masm, result, falseValue); 378 cmove(crb, masm, result, condition, trueValue); 379 380 if (isFloat) { 381 if (unorderedIsTrue && !trueOnUnordered(condition)) { 382 cmove(crb, masm, result, ConditionFlag.Parity, trueValue); 383 } else if (!unorderedIsTrue && trueOnUnordered(condition)) { 384 cmove(crb, masm, result, ConditionFlag.Parity, falseValue); 385 } 386 } 387 } 388 389 private static void cmove(CompilationResultBuilder crb, AMD64MacroAssembler masm, Value result, ConditionFlag cond, Value other) { 390 if (isRegister(other)) { 391 assert !asRegister(other).equals(asRegister(result)) : "other already overwritten by previous move"; 392 switch ((AMD64Kind) other.getPlatformKind()) { 393 case BYTE: 394 case WORD: 395 case DWORD: 396 masm.cmovl(cond, asRegister(result), asRegister(other)); 397 break; 398 case QWORD: 399 masm.cmovq(cond, asRegister(result), asRegister(other)); 400 break; 401 default: 402 throw GraalError.shouldNotReachHere(); 403 } 404 } else { 405 AMD64Address addr = (AMD64Address) crb.asAddress(other); 406 switch ((AMD64Kind) other.getPlatformKind()) { 407 case BYTE: 408 case WORD: 409 case DWORD: 410 masm.cmovl(cond, asRegister(result), addr); 411 break; 412 case QWORD: 413 masm.cmovq(cond, asRegister(result), addr); 414 break; 415 default: 416 throw GraalError.shouldNotReachHere(); 417 } 418 } 419 } 420 421 private static ConditionFlag intCond(Condition cond) { 422 switch (cond) { 423 case EQ: 424 return ConditionFlag.Equal; 425 case NE: 426 return ConditionFlag.NotEqual; 427 case LT: 428 return ConditionFlag.Less; 429 case LE: 430 return ConditionFlag.LessEqual; 431 case GE: 432 return ConditionFlag.GreaterEqual; 433 case GT: 434 return ConditionFlag.Greater; 435 case BE: 436 return ConditionFlag.BelowEqual; 437 case AE: 438 return ConditionFlag.AboveEqual; 439 case AT: 440 return ConditionFlag.Above; 441 case BT: 442 return ConditionFlag.Below; 443 default: 444 throw GraalError.shouldNotReachHere(); 445 } 446 } 447 448 private static ConditionFlag floatCond(Condition cond) { 449 switch (cond) { 450 case EQ: 451 return ConditionFlag.Equal; 452 case NE: 453 return ConditionFlag.NotEqual; 454 case LT: 455 return ConditionFlag.Below; 456 case LE: 457 return ConditionFlag.BelowEqual; 458 case GE: 459 return ConditionFlag.AboveEqual; 460 case GT: 461 return ConditionFlag.Above; 462 default: 463 throw GraalError.shouldNotReachHere(); 464 } 465 } 466 467 private static boolean trueOnUnordered(ConditionFlag condition) { 468 switch (condition) { 469 case AboveEqual: 470 case NotEqual: 471 case Above: 472 case Less: 473 case Overflow: 474 return false; 475 case Equal: 476 case BelowEqual: 477 case Below: 478 case GreaterEqual: 479 case NoOverflow: 480 return true; 481 default: 482 throw GraalError.shouldNotReachHere(); 483 } 484 } 485 }