| // Copyright 2023 The Bazel Authors. All rights reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| package com.google.devtools.build.lib.analysis.producers; |
| |
| import com.google.devtools.build.lib.analysis.TargetAndConfiguration; |
| import com.google.devtools.build.lib.analysis.ToolchainCollection; |
| import com.google.devtools.build.lib.analysis.TransitiveDependencyState; |
| import com.google.devtools.build.lib.analysis.config.ConfigConditions; |
| import com.google.devtools.build.lib.analysis.platform.PlatformInfo; |
| import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException; |
| import com.google.devtools.build.lib.skyframe.config.BuildConfigurationKey; |
| import com.google.devtools.build.lib.skyframe.toolchains.ToolchainException; |
| import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext; |
| import com.google.devtools.build.skyframe.state.StateMachine; |
| import javax.annotation.Nullable; |
| |
| /** |
| * This class computes the unloaded toolchain context and {@link ConfigConditions}. |
| * |
| * <p>It uses {@link PlatformInfo} derived from the unloaded toolchain contexts to compute config |
| * conditions, creating a sequential dependency between the two. |
| * |
| * <p>It's possible to use {@link DependencyContextProducerWithCompatibilityCheck} here instead but |
| * that necessarily evaluates {@link ConfigConditions} before computing the unloaded toolchain |
| * contexts, which in turn requires evaluating {@link PlatformInfo} in advance. This ordering is |
| * necessary because the compatibility check must precede the unloaded toolchain contexts |
| * computation. |
| * |
| * <p>This producer optimizes for the case where no compatibility check is needed and saves memory |
| * by using the {@link PlatformInfo} computed as a side effect of the unloaded toolchain contexts. |
| */ |
| public final class DependencyContextProducer |
| implements StateMachine, |
| UnloadedToolchainContextsProducer.ResultSink, |
| ConfigConditionsProducer.ResultSink { |
| /** |
| * Accepts results for both {@link DependencyContextProducer} and {@link |
| * DependencyContextProducerWithCompatibilityCheck}. |
| */ |
| public interface ResultSink { |
| void acceptDependencyContext(DependencyContext value); |
| |
| void acceptDependencyContextError(DependencyContextError error); |
| } |
| |
| // -------------------- Input -------------------- |
| private final UnloadedToolchainContextsInputs unloadedToolchainContextsInputs; |
| private final TargetAndConfiguration targetAndConfiguration; |
| private final BuildConfigurationKey buildConfigurationKey; |
| private final TransitiveDependencyState transitiveState; |
| |
| // -------------------- Output -------------------- |
| private final ResultSink sink; |
| |
| // -------------------- Internal State -------------------- |
| @Nullable // Will be null if the target doesn't require toolchain resolution. |
| private ToolchainCollection<UnloadedToolchainContext> unloadedToolchainContexts; |
| private ConfigConditions configConditions; |
| boolean hasError = false; |
| |
| public DependencyContextProducer( |
| UnloadedToolchainContextsInputs unloadedToolchainContextsInputs, |
| TargetAndConfiguration targetAndConfiguration, |
| BuildConfigurationKey buildConfigurationKey, |
| TransitiveDependencyState transitiveState, |
| ResultSink sink) { |
| this.unloadedToolchainContextsInputs = unloadedToolchainContextsInputs; |
| this.buildConfigurationKey = buildConfigurationKey; |
| this.unloadedToolchainContexts = null; |
| this.targetAndConfiguration = targetAndConfiguration; |
| this.transitiveState = transitiveState; |
| this.sink = sink; |
| } |
| |
| @Override |
| public StateMachine step(Tasks tasks) { |
| return new UnloadedToolchainContextsProducer( |
| unloadedToolchainContextsInputs, |
| (UnloadedToolchainContextsProducer.ResultSink) this, |
| /* runAfter= */ this::computeConfigConditions); |
| } |
| |
| @Override |
| public void acceptUnloadedToolchainContexts( |
| @Nullable ToolchainCollection<UnloadedToolchainContext> unloadedToolchainContexts) { |
| this.unloadedToolchainContexts = unloadedToolchainContexts; |
| } |
| |
| @Override |
| public void acceptUnloadedToolchainContextsError(ToolchainException error) { |
| this.hasError = true; |
| sink.acceptDependencyContextError(DependencyContextError.of(error)); |
| } |
| |
| private StateMachine computeConfigConditions(Tasks tasks) { |
| if (hasError) { |
| return DONE; |
| } |
| |
| return new ConfigConditionsProducer( |
| targetAndConfiguration.getTarget(), |
| targetAndConfiguration.getTarget().getLabel(), |
| buildConfigurationKey, |
| unloadedToolchainContexts == null ? null : unloadedToolchainContexts.getTargetPlatform(), |
| transitiveState, |
| (ConfigConditionsProducer.ResultSink) this, |
| /* runAfter= */ this::constructResult); |
| } |
| |
| @Override |
| public void acceptConfigConditions(ConfigConditions configConditions) { |
| this.configConditions = configConditions; |
| } |
| |
| @Override |
| public void acceptConfigConditionsError(ConfiguredValueCreationException error) { |
| this.hasError = true; |
| sink.acceptDependencyContextError(DependencyContextError.of(error)); |
| } |
| |
| private StateMachine constructResult(Tasks tasks) { |
| if (hasError) { |
| return DONE; |
| } |
| |
| sink.acceptDependencyContext( |
| DependencyContext.create(unloadedToolchainContexts, configConditions)); |
| return DONE; |
| } |
| } |