| // Copyright 2020 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; |
| |
| import static com.google.common.base.Preconditions.checkNotNull; |
| |
| import com.google.common.collect.Collections2; |
| import com.google.devtools.build.lib.analysis.config.BuildConfigurationValue; |
| import com.google.devtools.build.lib.analysis.config.BuildOptionDetails; |
| import com.google.devtools.build.lib.analysis.config.ConfigConditions; |
| import com.google.devtools.build.lib.analysis.config.CoreOptions; |
| import com.google.devtools.build.lib.analysis.config.CoreOptions.IncludeConfigFragmentsEnum; |
| import com.google.devtools.build.lib.analysis.config.Fragment; |
| import com.google.devtools.build.lib.analysis.config.FragmentClassSet; |
| import com.google.devtools.build.lib.analysis.config.transitions.TransitionFactory; |
| import com.google.devtools.build.lib.analysis.starlark.StarlarkAttributeTransitionProvider; |
| import com.google.devtools.build.lib.packages.Aspect; |
| import com.google.devtools.build.lib.packages.Attribute; |
| import com.google.devtools.build.lib.packages.AttributeTransitionData; |
| import com.google.devtools.build.lib.packages.ConfigurationFragmentPolicy; |
| import com.google.devtools.build.lib.packages.ConfiguredAttributeMapper; |
| import com.google.devtools.build.lib.packages.Rule; |
| import com.google.devtools.build.lib.packages.RuleClass; |
| import com.google.devtools.build.lib.packages.RuleTransitionData; |
| import com.google.devtools.build.lib.skyframe.ConfiguredTargetAndData; |
| import java.util.Objects; |
| import javax.annotation.Nullable; |
| |
| /** |
| * Utility methods for determining what {@link Fragment}s are required to analyze targets. |
| * |
| * <p>For example if a target reads <code>--copt</code> as part of its analysis logic, it requires |
| * the {@link com.google.devtools.build.lib.rules.cpp.CppConfiguration} fragment. |
| * |
| * <p>Used by {@link |
| * com.google.devtools.build.lib.query2.cquery.CqueryOptions#showRequiredConfigFragments}. |
| */ |
| public final class RequiredFragmentsUtil { |
| |
| /** |
| * Returns a {@link RequiredConfigFragmentsProvider} identifying all pieces of configuration a |
| * target requires, or {@code null} if required config fragments are not enabled (see {@link |
| * CoreOptions#includeRequiredConfigFragmentsProvider}). |
| * |
| * <p>The returned config state includes things that are known to be required at the time when the |
| * target's dependencies have already been analyzed but before it's been analyzed itself. See |
| * {@link RuleConfiguredTargetBuilder#maybeAddRequiredConfigFragmentsProvider} for the remaining |
| * pieces of config state. |
| * |
| * <p>If {@code configuration} is {@link CoreOptions.IncludeConfigFragmentsEnum#DIRECT}, the |
| * result includes only the config state considered to be directly required by this target. If |
| * it's {@link CoreOptions.IncludeConfigFragmentsEnum#TRANSITIVE}, it also includes config state |
| * needed by transitive dependencies. If it's {@link CoreOptions.IncludeConfigFragmentsEnum#OFF}, |
| * this method returns {@code null}. |
| * |
| * <p>{@code select()}s and toolchain dependencies are considered when looking at what config |
| * state is required. |
| * |
| * @param target the target |
| * @param configuration the configuration for this target |
| * @param universallyRequiredFragments fragments that are always required even if not explicitly |
| * specified for this target |
| * @param configConditions <code>config_settings</code> required by this target's <code>select |
| * </code>s. Used for a) figuring out which options <code>select</code>s read and b) figuring |
| * out which transitions are attached to the target. {@link TransitionFactory}, which |
| * determines the transitions, may read the target's attributes. |
| * @param prerequisites all prerequisites of {@code target} |
| * @param starlarkExecTransition the Starlark transition implementing the exec transition |
| * @return {@link RequiredConfigFragmentsProvider} or {@code null} if not enabled |
| */ |
| @Nullable |
| public static RequiredConfigFragmentsProvider getRuleRequiredFragmentsIfEnabled( |
| Rule target, |
| BuildConfigurationValue configuration, |
| FragmentClassSet universallyRequiredFragments, |
| ConfigConditions configConditions, |
| Iterable<ConfiguredTarget> prerequisites, |
| @Nullable StarlarkAttributeTransitionProvider starlarkExecTransition) { |
| IncludeConfigFragmentsEnum mode = getRequiredFragmentsMode(configuration); |
| if (mode == IncludeConfigFragmentsEnum.OFF) { |
| return null; |
| } |
| RuleClass ruleClass = target.getRuleClassObject(); |
| ConfiguredAttributeMapper attributes = |
| ConfiguredAttributeMapper.of(target, configConditions.asProviders(), configuration); |
| RequiredConfigFragmentsProvider.Builder requiredFragments = |
| getRequiredFragments( |
| mode, |
| configuration, |
| universallyRequiredFragments, |
| ruleClass.getConfigurationFragmentPolicy(), |
| configConditions, |
| prerequisites); |
| if (!ruleClass.isStarlark()) { |
| ruleClass |
| .getConfiguredTargetFactory(RuleConfiguredTargetFactory.class) |
| .addRuleImplSpecificRequiredConfigFragments(requiredFragments, attributes, configuration); |
| } |
| addRequiredFragmentsFromRuleTransitions( |
| configConditions, |
| configuration.checksum(), |
| requiredFragments, |
| target, |
| attributes, |
| configuration.getBuildOptionDetails(), |
| starlarkExecTransition); |
| |
| // We consider build settings (which are both targets and configuration) to require themselves. |
| if (target.isBuildSetting()) { |
| requiredFragments.addStarlarkOption(target.getLabel()); |
| } |
| |
| return requiredFragments.build(); |
| } |
| |
| /** |
| * Variation of {@link #getRuleRequiredFragmentsIfEnabled} for aspects. |
| * |
| * @param aspect the aspect |
| * @param aspectFactory the corresponding {@link ConfiguredAspectFactory} |
| * @param associatedTarget the target this aspect is attached to |
| * @param configuration the configuration for this aspect |
| * @param universallyRequiredFragments fragments that are always required even if not explicitly |
| * specified for this aspect |
| * @param configConditions <code>config_settings</code> required by <code>select</code>s on the |
| * associated target. Used for figuring out which transitions are attached to the target. |
| * @param prerequisites all prerequisites of {@code aspect} |
| * @param starlarkExecTransition the Starlark transition implementing the exec transition |
| * @return {@link RequiredConfigFragmentsProvider} or {@code null} if not enabled |
| */ |
| @Nullable |
| public static RequiredConfigFragmentsProvider getAspectRequiredFragmentsIfEnabled( |
| Aspect aspect, |
| ConfiguredAspectFactory aspectFactory, |
| Rule associatedTarget, |
| BuildConfigurationValue configuration, |
| FragmentClassSet universallyRequiredFragments, |
| ConfigConditions configConditions, |
| Iterable<ConfiguredTarget> prerequisites, |
| StarlarkAttributeTransitionProvider starlarkExecTransition) { |
| IncludeConfigFragmentsEnum mode = getRequiredFragmentsMode(configuration); |
| if (mode == IncludeConfigFragmentsEnum.OFF) { |
| return null; |
| } |
| RequiredConfigFragmentsProvider.Builder requiredFragments = |
| getRequiredFragments( |
| mode, |
| configuration, |
| universallyRequiredFragments, |
| aspect.getDefinition().getConfigurationFragmentPolicy(), |
| configConditions, |
| prerequisites); |
| aspectFactory.addAspectImplSpecificRequiredConfigFragments(requiredFragments); |
| addRequiredFragmentsFromAspectTransitions( |
| requiredFragments, |
| aspect, |
| ConfiguredAttributeMapper.of( |
| associatedTarget, configConditions.asProviders(), configuration), |
| configuration.getBuildOptionDetails(), |
| starlarkExecTransition); |
| return requiredFragments.build(); |
| } |
| |
| /** Internal implementation that handles requirements common to both rules and aspects. */ |
| private static RequiredConfigFragmentsProvider.Builder getRequiredFragments( |
| IncludeConfigFragmentsEnum mode, |
| BuildConfigurationValue configuration, |
| FragmentClassSet universallyRequiredFragments, |
| ConfigurationFragmentPolicy configurationFragmentPolicy, |
| ConfigConditions configConditions, |
| Iterable<ConfiguredTarget> prerequisites) { |
| RequiredConfigFragmentsProvider.Builder requiredFragments = |
| RequiredConfigFragmentsProvider.builder(); |
| |
| if (mode == IncludeConfigFragmentsEnum.TRANSITIVE) { |
| // Add transitive requirements first, which results in better performance. See explanation on |
| // RequiredConfigFragmentsProvider.Builder. |
| addTransitivelyRequiredFragments(requiredFragments, prerequisites); |
| } else { |
| addStarlarkBuildSettings(requiredFragments, prerequisites); |
| } |
| |
| // Add directly required fragments: |
| requiredFragments |
| // Fragments explicitly required by the native target/aspect definition API: |
| .addFragmentClasses(configurationFragmentPolicy.getRequiredConfigurationFragments()) |
| // Fragments explicitly required by the Starlark target/aspect definition API (nulls are |
| // filtered because the rule definition may reference non-existent fragments): |
| .addFragmentClasses( |
| Collections2.filter( |
| Collections2.transform( |
| configurationFragmentPolicy.getRequiredStarlarkFragments(), |
| configuration::getStarlarkFragmentByName), |
| Objects::nonNull)) |
| // Fragments universally required by everything: |
| .addFragmentClasses(universallyRequiredFragments); |
| // Fragments required by attached select()s. Propagating fragments from the config conditions as |
| // configured targets (rather than as providers) is necessary in case of a dependency on an |
| // alias that resolves to a config setting. Providers only reflect the resolved settings, which |
| // won't include fragments required to resolve a select within the alias rule (b/237534193). |
| for (ConfiguredTargetAndData targetAndData : configConditions.asConfiguredTargets().values()) { |
| requiredFragments.merge( |
| targetAndData.getConfiguredTarget().getProvider(RequiredConfigFragmentsProvider.class)); |
| } |
| return requiredFragments; |
| } |
| |
| /** |
| * Adds required fragments from transitions "attached" to a target. |
| * |
| * <p>"Attached" means the transition is attached to the target itself or one of its attributes. |
| * |
| * <p>These are the transitions required for a target to successfully analyze. Technically, |
| * transitions attached to the target are evaluated during its parent's analysis, which is where |
| * the configuration for the child is determined. We still consider these the child's requirements |
| * because the child's properties determine that dependency. |
| */ |
| private static void addRequiredFragmentsFromRuleTransitions( |
| ConfigConditions configConditions, |
| String configHash, |
| RequiredConfigFragmentsProvider.Builder requiredFragments, |
| Rule target, |
| ConfiguredAttributeMapper attributeMap, |
| BuildOptionDetails optionDetails, |
| @Nullable StarlarkAttributeTransitionProvider starlarkExecTransition) { |
| target |
| .getRuleClassObject() |
| .getTransitionFactory() |
| .create(RuleTransitionData.create(target, configConditions.asProviders(), configHash)) |
| .addRequiredFragments(requiredFragments, optionDetails); |
| // We don't set the execution platform in this data because a) that doesn't affect which |
| // fragments are required and b) it's one less parameter we have to pass to |
| // RequiredFragmenstUtil's public interface. |
| AttributeTransitionData attributeTransitionData = |
| AttributeTransitionData.builder() |
| .attributes(attributeMap) |
| .analysisData(starlarkExecTransition) |
| .build(); |
| for (Attribute attribute : target.getRuleClassObject().getAttributeProvider().getAttributes()) { |
| if (attribute.getTransitionFactory() != null) { |
| attribute |
| .getTransitionFactory() |
| .create(attributeTransitionData) |
| .addRequiredFragments(requiredFragments, optionDetails); |
| } |
| } |
| } |
| |
| /** |
| * Adds required fragments from transitions "attached" to an aspect. |
| * |
| * <p>"Attached" means the transition is attached to one of the aspect's attributes. Transitions |
| * can't be attached directly to aspects themselves. |
| */ |
| private static void addRequiredFragmentsFromAspectTransitions( |
| RequiredConfigFragmentsProvider.Builder requiredFragments, |
| Aspect aspect, |
| ConfiguredAttributeMapper attributeMap, |
| BuildOptionDetails optionDetails, |
| StarlarkAttributeTransitionProvider starlarkExecTransition) { |
| AttributeTransitionData attributeTransitionData = |
| AttributeTransitionData.builder() |
| .attributes(attributeMap) |
| .analysisData(starlarkExecTransition) |
| .build(); |
| for (Attribute attribute : aspect.getDefinition().getAttributes().values()) { |
| if (attribute.getTransitionFactory() != null) { |
| attribute |
| .getTransitionFactory() |
| .create(attributeTransitionData) |
| .addRequiredFragments(requiredFragments, optionDetails); |
| } |
| } |
| } |
| |
| private static void addTransitivelyRequiredFragments( |
| RequiredConfigFragmentsProvider.Builder requiredFragments, |
| Iterable<ConfiguredTarget> prerequisites) { |
| for (ConfiguredTarget prereq : prerequisites) { |
| RequiredConfigFragmentsProvider depProvider = |
| prereq.getProvider(RequiredConfigFragmentsProvider.class); |
| if (depProvider != null) { |
| requiredFragments.merge(depProvider); |
| } |
| } |
| } |
| |
| /** |
| * Adds dependencies on Starlark build settings. |
| * |
| * <p>Starlark build settings are considered direct requirements on the rule even though they are |
| * technically dependencies. Note that this method only needs to be called in {@link |
| * IncludeConfigFragmentsEnum#DIRECT} mode, since {@link IncludeConfigFragmentsEnum#TRANSITIVE} |
| * mode will already pick up these requirements from dependencies. |
| */ |
| private static void addStarlarkBuildSettings( |
| RequiredConfigFragmentsProvider.Builder requiredFragments, |
| Iterable<ConfiguredTarget> prerequisites) { |
| for (ConfiguredTarget prereq : prerequisites) { |
| BuildSettingProvider buildSettingProvider = prereq.getProvider(BuildSettingProvider.class); |
| if (buildSettingProvider != null) { |
| requiredFragments.addStarlarkOption(buildSettingProvider.getLabel()); |
| } |
| } |
| } |
| |
| private static IncludeConfigFragmentsEnum getRequiredFragmentsMode( |
| BuildConfigurationValue config) { |
| return checkNotNull( |
| config.getOptions().get(CoreOptions.class).includeRequiredConfigFragmentsProvider); |
| } |
| |
| private RequiredFragmentsUtil() {} |
| } |
