1 /*
   2  * Copyright (c) 2012, 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.hotspot.stubs;
  24 
  25 import static org.graalvm.compiler.core.GraalCompiler.emitBackEnd;
  26 import static org.graalvm.compiler.core.GraalCompiler.emitFrontEnd;
  27 import static org.graalvm.compiler.core.common.GraalOptions.GeneratePIC;
  28 import static org.graalvm.compiler.hotspot.HotSpotHostBackend.UNCOMMON_TRAP_HANDLER;
  29 
  30 import java.util.ArrayList;
  31 import java.util.Collection;
  32 import java.util.Collections;
  33 import java.util.List;
  34 import java.util.ListIterator;
  35 import java.util.Set;
  36 
  37 import org.graalvm.compiler.code.CompilationResult;
  38 import org.graalvm.compiler.core.common.CompilationIdentifier;
  39 import org.graalvm.compiler.core.target.Backend;
  40 import org.graalvm.compiler.debug.Debug;
  41 import org.graalvm.compiler.debug.Debug.Scope;
  42 import org.graalvm.compiler.debug.internal.DebugScope;
  43 import org.graalvm.compiler.hotspot.HotSpotCompiledCodeBuilder;
  44 import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage;
  45 import org.graalvm.compiler.hotspot.meta.HotSpotProviders;
  46 import org.graalvm.compiler.hotspot.nodes.StubStartNode;
  47 import org.graalvm.compiler.lir.asm.CompilationResultBuilderFactory;
  48 import org.graalvm.compiler.lir.phases.LIRPhase;
  49 import org.graalvm.compiler.lir.phases.LIRSuites;
  50 import org.graalvm.compiler.lir.phases.PostAllocationOptimizationPhase.PostAllocationOptimizationContext;
  51 import org.graalvm.compiler.lir.profiling.MoveProfilingPhase;
  52 import org.graalvm.compiler.nodes.StructuredGraph;
  53 import org.graalvm.compiler.phases.OptimisticOptimizations;
  54 import org.graalvm.compiler.phases.PhaseSuite;
  55 import org.graalvm.compiler.phases.tiers.Suites;
  56 
  57 import jdk.vm.ci.code.CodeCacheProvider;
  58 import jdk.vm.ci.code.InstalledCode;
  59 import jdk.vm.ci.code.Register;
  60 import jdk.vm.ci.code.RegisterConfig;
  61 import jdk.vm.ci.code.site.Call;
  62 import jdk.vm.ci.code.site.ConstantReference;
  63 import jdk.vm.ci.code.site.DataPatch;
  64 import jdk.vm.ci.code.site.Infopoint;
  65 import jdk.vm.ci.hotspot.HotSpotCompiledCode;
  66 import jdk.vm.ci.hotspot.HotSpotMetaspaceConstant;
  67 import jdk.vm.ci.meta.DefaultProfilingInfo;
  68 import jdk.vm.ci.meta.ResolvedJavaMethod;
  69 import jdk.vm.ci.meta.TriState;
  70 
  71 //JaCoCo Exclude
  72 
  73 /**
  74  * Base class for implementing some low level code providing the out-of-line slow path for a snippet
  75  * and/or a callee saved call to a HotSpot C/C++ runtime function or even a another compiled Java
  76  * method.
  77  */
  78 public abstract class Stub {
  79 
  80     private static final List<Stub> stubs = new ArrayList<>();
  81 
  82     /**
  83      * The linkage information for a call to this stub from compiled code.
  84      */
  85     protected final HotSpotForeignCallLinkage linkage;
  86 
  87     /**
  88      * The code installed for the stub.
  89      */
  90     protected InstalledCode code;
  91 
  92     /**
  93      * The registers destroyed by this stub (from the caller's perspective).
  94      */
  95     private Set<Register> destroyedCallerRegisters;
  96 
  97     public void initDestroyedCallerRegisters(Set<Register> registers) {
  98         assert registers != null;
  99         assert destroyedCallerRegisters == null || registers.equals(destroyedCallerRegisters) : "cannot redefine";
 100         destroyedCallerRegisters = registers;
 101     }
 102 
 103     /**
 104      * Gets the registers destroyed by this stub from a caller's perspective. These are the
 105      * temporaries of this stub and must thus be caller saved by a callers of this stub.
 106      */
 107     public Set<Register> getDestroyedCallerRegisters() {
 108         assert destroyedCallerRegisters != null : "not yet initialized";
 109         return destroyedCallerRegisters;
 110     }
 111 
 112     /**
 113      * Determines if this stub preserves all registers apart from those it
 114      * {@linkplain #getDestroyedCallerRegisters() destroys}.
 115      */
 116     public boolean preservesRegisters() {
 117         return true;
 118     }
 119 
 120     protected final HotSpotProviders providers;
 121 
 122     /**
 123      * Creates a new stub.
 124      *
 125      * @param linkage linkage details for a call to the stub
 126      */
 127     public Stub(HotSpotProviders providers, HotSpotForeignCallLinkage linkage) {
 128         this.linkage = linkage;
 129         this.providers = providers;
 130         stubs.add(this);
 131     }
 132 
 133     /**
 134      * Gets an immutable view of all stubs that have been created.
 135      */
 136     public static Collection<Stub> getStubs() {
 137         return Collections.unmodifiableList(stubs);
 138     }
 139 
 140     /**
 141      * Gets the linkage for a call to this stub from compiled code.
 142      */
 143     public HotSpotForeignCallLinkage getLinkage() {
 144         return linkage;
 145     }
 146 
 147     public RegisterConfig getRegisterConfig() {
 148         return null;
 149     }
 150 
 151     /**
 152      * Gets the graph that from which the code for this stub will be compiled.
 153      *
 154      * @param compilationId unique compilation id for the stub
 155      */
 156     protected abstract StructuredGraph getGraph(CompilationIdentifier compilationId);
 157 
 158     @Override
 159     public String toString() {
 160         return "Stub<" + linkage.getDescriptor() + ">";
 161     }
 162 
 163     /**
 164      * Gets the method the stub's code will be associated with once installed. This may be null.
 165      */
 166     protected abstract ResolvedJavaMethod getInstalledCodeOwner();
 167 
 168     /**
 169      * Gets a context object for the debug scope created when producing the code for this stub.
 170      */
 171     protected abstract Object debugScopeContext();
 172 
 173     /**
 174      * Gets the code for this stub, compiling it first if necessary.
 175      */
 176     @SuppressWarnings("try")
 177     public synchronized InstalledCode getCode(final Backend backend) {
 178         if (code == null) {
 179             try (Scope d = Debug.sandbox("CompilingStub", DebugScope.getConfig(), providers.getCodeCache(), debugScopeContext())) {
 180                 CodeCacheProvider codeCache = providers.getCodeCache();
 181                 CompilationResult compResult = buildCompilationResult(backend);
 182                 try (Scope s = Debug.scope("CodeInstall", compResult)) {
 183                     assert destroyedCallerRegisters != null;
 184                     // Add a GeneratePIC check here later, we don't want to install
 185                     // code if we don't have a corresponding VM global symbol.
 186                     HotSpotCompiledCode compiledCode = HotSpotCompiledCodeBuilder.createCompiledCode(null, null, compResult);
 187                     code = codeCache.installCode(null, compiledCode, null, null, false);
 188                 } catch (Throwable e) {
 189                     throw Debug.handle(e);
 190                 }
 191             } catch (Throwable e) {
 192                 throw Debug.handle(e);
 193             }
 194             assert code != null : "error installing stub " + this;
 195         }
 196 
 197         return code;
 198     }
 199 
 200     @SuppressWarnings("try")
 201     private CompilationResult buildCompilationResult(final Backend backend) {
 202         CompilationResult compResult = new CompilationResult(toString(), GeneratePIC.getValue());
 203         final StructuredGraph graph = getGraph(getStubCompilationId());
 204 
 205         // Stubs cannot be recompiled so they cannot be compiled with assumptions
 206         assert graph.getAssumptions() == null;
 207 
 208         if (!(graph.start() instanceof StubStartNode)) {
 209             StubStartNode newStart = graph.add(new StubStartNode(Stub.this));
 210             newStart.setStateAfter(graph.start().stateAfter());
 211             graph.replaceFixed(graph.start(), newStart);
 212         }
 213 
 214         try (Scope s0 = Debug.scope("StubCompilation", graph, providers.getCodeCache())) {
 215             Suites suites = createSuites();
 216             emitFrontEnd(providers, backend, graph, providers.getSuites().getDefaultGraphBuilderSuite(), OptimisticOptimizations.ALL, DefaultProfilingInfo.get(TriState.UNKNOWN), suites);
 217             LIRSuites lirSuites = createLIRSuites();
 218             emitBackEnd(graph, Stub.this, getInstalledCodeOwner(), backend, compResult, CompilationResultBuilderFactory.Default, getRegisterConfig(), lirSuites);
 219             assert checkStubInvariants(compResult);
 220         } catch (Throwable e) {
 221             throw Debug.handle(e);
 222         }
 223         return compResult;
 224     }
 225 
 226     /**
 227      * Gets a {@link CompilationResult} that can be used for code generation. Required for AOT.
 228      */
 229     @SuppressWarnings("try")
 230     public CompilationResult getCompilationResult(final Backend backend) {
 231         try (Scope d = Debug.sandbox("CompilingStub", DebugScope.getConfig(), providers.getCodeCache(), debugScopeContext())) {
 232             return buildCompilationResult(backend);
 233         } catch (Throwable e) {
 234             throw Debug.handle(e);
 235         }
 236     }
 237 
 238     public CompilationIdentifier getStubCompilationId() {
 239         return new StubCompilationIdentifier(this);
 240     }
 241 
 242     /**
 243      * Checks the conditions a compilation must satisfy to be installed as a RuntimeStub.
 244      */
 245     private boolean checkStubInvariants(CompilationResult compResult) {
 246         assert compResult.getExceptionHandlers().isEmpty() : this;
 247 
 248         // Stubs cannot be recompiled so they cannot be compiled with
 249         // assumptions and there is no point in recording evol_method dependencies
 250         assert compResult.getAssumptions() == null : "stubs should not use assumptions: " + this;
 251 
 252         for (DataPatch data : compResult.getDataPatches()) {
 253             if (data.reference instanceof ConstantReference) {
 254                 ConstantReference ref = (ConstantReference) data.reference;
 255                 if (ref.getConstant() instanceof HotSpotMetaspaceConstant) {
 256                     HotSpotMetaspaceConstant c = (HotSpotMetaspaceConstant) ref.getConstant();
 257                     if (c.asResolvedJavaType() != null && c.asResolvedJavaType().getName().equals("[I")) {
 258                         // special handling for NewArrayStub
 259                         // embedding the type '[I' is safe, since it is never unloaded
 260                         continue;
 261                     }
 262                 }
 263             }
 264 
 265             assert !(data.reference instanceof ConstantReference) : this + " cannot have embedded object or metadata constant: " + data.reference;
 266         }
 267         for (Infopoint infopoint : compResult.getInfopoints()) {
 268             assert infopoint instanceof Call : this + " cannot have non-call infopoint: " + infopoint;
 269             Call call = (Call) infopoint;
 270             assert call.target instanceof HotSpotForeignCallLinkage : this + " cannot have non runtime call: " + call.target;
 271             HotSpotForeignCallLinkage callLinkage = (HotSpotForeignCallLinkage) call.target;
 272             assert !callLinkage.isCompiledStub() || callLinkage.getDescriptor().equals(UNCOMMON_TRAP_HANDLER) : this + " cannot call compiled stub " + callLinkage;
 273         }
 274         return true;
 275     }
 276 
 277     protected Suites createSuites() {
 278         Suites defaultSuites = providers.getSuites().getDefaultSuites();
 279         return new Suites(new PhaseSuite<>(), defaultSuites.getMidTier(), defaultSuites.getLowTier());
 280     }
 281 
 282     protected LIRSuites createLIRSuites() {
 283         LIRSuites lirSuites = new LIRSuites(providers.getSuites().getDefaultLIRSuites());
 284         ListIterator<LIRPhase<PostAllocationOptimizationContext>> moveProfiling = lirSuites.getPostAllocationOptimizationStage().findPhase(MoveProfilingPhase.class);
 285         if (moveProfiling != null) {
 286             moveProfiling.remove();
 287         }
 288         return lirSuites;
 289     }
 290 }