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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package org.graalvm.compiler.hotspot.stubs;

import static org.graalvm.compiler.core.GraalCompiler.emitFrontEnd;
import static org.graalvm.compiler.core.common.GraalOptions.GeneratePIC;
import static org.graalvm.compiler.core.common.GraalOptions.RegisterPressure;
import static org.graalvm.compiler.debug.DebugOptions.DebugStubsAndSnippets;
import static org.graalvm.compiler.hotspot.HotSpotHostBackend.DEOPT_BLOB_UNCOMMON_TRAP;
import static org.graalvm.util.CollectionsUtil.allMatch;

import java.util.ListIterator;
import java.util.concurrent.atomic.AtomicInteger;

import jdk.internal.vm.compiler.collections.EconomicSet;
import org.graalvm.compiler.code.CompilationResult;
import org.graalvm.compiler.core.common.CompilationIdentifier;
import org.graalvm.compiler.core.common.GraalOptions;
import org.graalvm.compiler.core.target.Backend;
import org.graalvm.compiler.debug.DebugContext;
import org.graalvm.compiler.debug.DebugContext.Builder;
import org.graalvm.compiler.debug.DebugContext.Description;
import org.graalvm.compiler.hotspot.HotSpotCompiledCodeBuilder;
import org.graalvm.compiler.hotspot.HotSpotForeignCallLinkage;
import org.graalvm.compiler.hotspot.meta.HotSpotProviders;
import org.graalvm.compiler.hotspot.nodes.StubStartNode;
import org.graalvm.compiler.lir.asm.CompilationResultBuilderFactory;
import org.graalvm.compiler.lir.phases.LIRPhase;
import org.graalvm.compiler.lir.phases.LIRSuites;
import org.graalvm.compiler.lir.phases.PostAllocationOptimizationPhase.PostAllocationOptimizationContext;
import org.graalvm.compiler.lir.profiling.MoveProfilingPhase;
import org.graalvm.compiler.nodes.StructuredGraph;
import org.graalvm.compiler.options.OptionValues;
import org.graalvm.compiler.phases.OptimisticOptimizations;
import org.graalvm.compiler.phases.PhaseSuite;
import org.graalvm.compiler.phases.tiers.Suites;
import org.graalvm.compiler.printer.GraalDebugHandlersFactory;

import jdk.vm.ci.code.CodeCacheProvider;
import jdk.vm.ci.code.InstalledCode;
import jdk.vm.ci.code.Register;
import jdk.vm.ci.code.RegisterConfig;
import jdk.vm.ci.code.site.Call;
import jdk.vm.ci.code.site.ConstantReference;
import jdk.vm.ci.code.site.DataPatch;
import jdk.vm.ci.code.site.Infopoint;
import jdk.vm.ci.hotspot.HotSpotCompiledCode;
import jdk.vm.ci.hotspot.HotSpotMetaspaceConstant;
import jdk.vm.ci.meta.DefaultProfilingInfo;
import jdk.vm.ci.meta.ResolvedJavaMethod;
import jdk.vm.ci.meta.TriState;

//JaCoCo Exclude

Base class for implementing some low level code providing the out-of-line slow path for a snippet and/or a callee saved call to a HotSpot C/C++ runtime function or even another compiled Java method.
/** * Base class for implementing some low level code providing the out-of-line slow path for a snippet * and/or a callee saved call to a HotSpot C/C++ runtime function or even another compiled Java * method. */
public abstract class Stub {
The linkage information for a call to this stub from compiled code.
/** * The linkage information for a call to this stub from compiled code. */
protected final HotSpotForeignCallLinkage linkage;
The code installed for the stub.
/** * The code installed for the stub. */
protected InstalledCode code;
The registers destroyed by this stub (from the caller's perspective).
/** * The registers destroyed by this stub (from the caller's perspective). */
private EconomicSet<Register> destroyedCallerRegisters; private static boolean checkRegisterSetEquivalency(EconomicSet<Register> a, EconomicSet<Register> b) { if (a == b) { return true; } if (a.size() != b.size()) { return false; } return allMatch(a, e -> b.contains(e)); } public void initDestroyedCallerRegisters(EconomicSet<Register> registers) { assert registers != null; assert destroyedCallerRegisters == null || checkRegisterSetEquivalency(registers, destroyedCallerRegisters) : "cannot redefine"; destroyedCallerRegisters = registers; }
Gets the registers destroyed by this stub from a caller's perspective. These are the temporaries of this stub and must thus be caller saved by a callers of this stub.
/** * Gets the registers destroyed by this stub from a caller's perspective. These are the * temporaries of this stub and must thus be caller saved by a callers of this stub. */
public EconomicSet<Register> getDestroyedCallerRegisters() { assert destroyedCallerRegisters != null : "not yet initialized"; return destroyedCallerRegisters; } public boolean shouldSaveRegistersAroundCalls() { return linkage.getEffect() == HotSpotForeignCallLinkage.RegisterEffect.COMPUTES_REGISTERS_KILLED; } protected final OptionValues options; protected final HotSpotProviders providers;
Creates a new stub.
Params:
  • linkage – linkage details for a call to the stub
/** * Creates a new stub. * * @param linkage linkage details for a call to the stub */
public Stub(OptionValues options, HotSpotProviders providers, HotSpotForeignCallLinkage linkage) { this.linkage = linkage; // The RegisterPressure flag can be ignored by a compilation that runs out of registers, so // the stub compilation must ignore the flag so that all allocatable registers are saved. this.options = new OptionValues(options, GraalOptions.TraceInlining, GraalOptions.TraceInliningForStubsAndSnippets.getValue(options), RegisterPressure, null); this.providers = providers; }
Gets the linkage for a call to this stub from compiled code.
/** * Gets the linkage for a call to this stub from compiled code. */
public HotSpotForeignCallLinkage getLinkage() { return linkage; } public RegisterConfig getRegisterConfig() { return null; }
Gets the graph that from which the code for this stub will be compiled.
Params:
  • compilationId – unique compilation id for the stub
/** * Gets the graph that from which the code for this stub will be compiled. * * @param compilationId unique compilation id for the stub */
protected abstract StructuredGraph getGraph(DebugContext debug, CompilationIdentifier compilationId); @Override public String toString() { return "Stub<" + linkage.getDescriptor().getSignature() + ">"; }
Gets the method the stub's code will be associated with once installed. This may be null.
/** * Gets the method the stub's code will be associated with once installed. This may be null. */
protected abstract ResolvedJavaMethod getInstalledCodeOwner();
Gets a context object for the debug scope created when producing the code for this stub.
/** * Gets a context object for the debug scope created when producing the code for this stub. */
protected abstract Object debugScopeContext(); private static final AtomicInteger nextStubId = new AtomicInteger(); private DebugContext openDebugContext(DebugContext outer) { if (DebugStubsAndSnippets.getValue(options)) { Description description = new Description(linkage, "Stub_" + nextStubId.incrementAndGet()); GraalDebugHandlersFactory factory = new GraalDebugHandlersFactory(providers.getSnippetReflection()); return new Builder(options, factory).globalMetrics(outer.getGlobalMetrics()).description(description).build(); } return DebugContext.disabled(options); }
Gets the code for this stub, compiling it first if necessary.
/** * Gets the code for this stub, compiling it first if necessary. */
@SuppressWarnings("try") public synchronized InstalledCode getCode(final Backend backend) { if (code == null) { try (DebugContext debug = openDebugContext(DebugContext.forCurrentThread())) { try (DebugContext.Scope d = debug.scope("CompilingStub", providers.getCodeCache(), debugScopeContext())) { CodeCacheProvider codeCache = providers.getCodeCache(); CompilationResult compResult = buildCompilationResult(debug, backend); try (DebugContext.Scope s = debug.scope("CodeInstall", compResult); DebugContext.Activation a = debug.activate()) { assert destroyedCallerRegisters != null; // Add a GeneratePIC check here later, we don't want to install // code if we don't have a corresponding VM global symbol. HotSpotCompiledCode compiledCode = HotSpotCompiledCodeBuilder.createCompiledCode(codeCache, null, null, compResult, options); code = codeCache.installCode(null, compiledCode, null, null, false); } catch (Throwable e) { throw debug.handle(e); } } catch (Throwable e) { throw debug.handle(e); } assert code != null : "error installing stub " + this; } } return code; } @SuppressWarnings("try") private CompilationResult buildCompilationResult(DebugContext debug, final Backend backend) { CompilationIdentifier compilationId = getStubCompilationId(); final StructuredGraph graph = getGraph(debug, compilationId); CompilationResult compResult = new CompilationResult(compilationId, toString(), GeneratePIC.getValue(options)); // Stubs cannot be recompiled so they cannot be compiled with assumptions assert graph.getAssumptions() == null; if (!(graph.start() instanceof StubStartNode)) { StubStartNode newStart = graph.add(new StubStartNode(Stub.this)); newStart.setStateAfter(graph.start().stateAfter()); graph.replaceFixed(graph.start(), newStart); } try (DebugContext.Scope s0 = debug.scope("StubCompilation", graph, providers.getCodeCache())) { Suites suites = createSuites(); emitFrontEnd(providers, backend, graph, providers.getSuites().getDefaultGraphBuilderSuite(), OptimisticOptimizations.ALL, DefaultProfilingInfo.get(TriState.UNKNOWN), suites); LIRSuites lirSuites = createLIRSuites(); backend.emitBackEnd(graph, Stub.this, getInstalledCodeOwner(), compResult, CompilationResultBuilderFactory.Default, getRegisterConfig(), lirSuites); assert checkStubInvariants(compResult); } catch (Throwable e) { throw debug.handle(e); } return compResult; }
Gets a CompilationResult that can be used for code generation. Required for AOT.
/** * Gets a {@link CompilationResult} that can be used for code generation. Required for AOT. */
@SuppressWarnings("try") public CompilationResult getCompilationResult(DebugContext debug, final Backend backend) { try (DebugContext.Scope d = debug.scope("CompilingStub", providers.getCodeCache(), debugScopeContext())) { return buildCompilationResult(debug, backend); } catch (Throwable e) { throw debug.handle(e); } } public CompilationIdentifier getStubCompilationId() { return new StubCompilationIdentifier(this); }
Checks the conditions a compilation must satisfy to be installed as a RuntimeStub.
/** * Checks the conditions a compilation must satisfy to be installed as a RuntimeStub. */
private boolean checkStubInvariants(CompilationResult compResult) { assert compResult.getExceptionHandlers().isEmpty() : this; // Stubs cannot be recompiled so they cannot be compiled with // assumptions and there is no point in recording evol_method dependencies assert compResult.getAssumptions() == null : "stubs should not use assumptions: " + this; for (DataPatch data : compResult.getDataPatches()) { if (data.reference instanceof ConstantReference) { ConstantReference ref = (ConstantReference) data.reference; if (ref.getConstant() instanceof HotSpotMetaspaceConstant) { HotSpotMetaspaceConstant c = (HotSpotMetaspaceConstant) ref.getConstant(); if (c.asResolvedJavaType() != null && c.asResolvedJavaType().getName().equals("[I")) { // special handling for NewArrayStub // embedding the type '[I' is safe, since it is never unloaded continue; } } } assert !(data.reference instanceof ConstantReference) : this + " cannot have embedded object or metadata constant: " + data.reference; } for (Infopoint infopoint : compResult.getInfopoints()) { assert infopoint instanceof Call : this + " cannot have non-call infopoint: " + infopoint; Call call = (Call) infopoint; assert call.target instanceof HotSpotForeignCallLinkage : this + " cannot have non runtime call: " + call.target; HotSpotForeignCallLinkage callLinkage = (HotSpotForeignCallLinkage) call.target; assert !callLinkage.isCompiledStub() || callLinkage.getDescriptor().equals(DEOPT_BLOB_UNCOMMON_TRAP) : this + " cannot call compiled stub " + callLinkage; } return true; } protected Suites createSuites() { Suites defaultSuites = providers.getSuites().getDefaultSuites(options); return new Suites(new PhaseSuite<>(), defaultSuites.getMidTier(), defaultSuites.getLowTier()); } protected LIRSuites createLIRSuites() { LIRSuites lirSuites = new LIRSuites(providers.getSuites().getDefaultLIRSuites(options)); ListIterator<LIRPhase<PostAllocationOptimizationContext>> moveProfiling = lirSuites.getPostAllocationOptimizationStage().findPhase(MoveProfilingPhase.class); if (moveProfiling != null) { moveProfiling.remove(); } return lirSuites; } }