| // Copyright 2014 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.devtools.build.lib.analysis.DependencyKind.OUTPUT_FILE_RULE_DEPENDENCY; |
| import static com.google.devtools.build.lib.analysis.DependencyKind.VISIBILITY_DEPENDENCY; |
| |
| import com.google.auto.value.AutoOneOf; |
| import com.google.common.annotations.VisibleForTesting; |
| import com.google.common.base.Preconditions; |
| import com.google.common.collect.ImmutableList; |
| import com.google.common.collect.ImmutableMap; |
| import com.google.common.collect.Iterables; |
| import com.google.devtools.build.lib.analysis.DependencyKind.AttributeDependencyKind; |
| import com.google.devtools.build.lib.analysis.config.BuildConfigurationValue; |
| import com.google.devtools.build.lib.analysis.config.ConfigMatchingProvider; |
| import com.google.devtools.build.lib.analysis.config.ExecutionTransitionFactory; |
| import com.google.devtools.build.lib.analysis.config.Fragment; |
| import com.google.devtools.build.lib.analysis.config.transitions.TransitionFactory; |
| import com.google.devtools.build.lib.analysis.platform.PlatformInfo; |
| import com.google.devtools.build.lib.cmdline.Label; |
| import com.google.devtools.build.lib.packages.Aspect; |
| import com.google.devtools.build.lib.packages.AspectClass; |
| import com.google.devtools.build.lib.packages.Attribute; |
| import com.google.devtools.build.lib.packages.Attribute.ComputedDefault; |
| import com.google.devtools.build.lib.packages.Attribute.LateBoundDefault; |
| import com.google.devtools.build.lib.packages.AttributeMap; |
| import com.google.devtools.build.lib.packages.AttributeTransitionData; |
| import com.google.devtools.build.lib.packages.BuildType; |
| import com.google.devtools.build.lib.packages.ConfiguredAttributeMapper; |
| import com.google.devtools.build.lib.packages.EnvironmentGroup; |
| import com.google.devtools.build.lib.packages.ExecGroup; |
| import com.google.devtools.build.lib.packages.InputFile; |
| import com.google.devtools.build.lib.packages.OutputFile; |
| import com.google.devtools.build.lib.packages.PackageGroup; |
| import com.google.devtools.build.lib.packages.Rule; |
| import com.google.devtools.build.lib.packages.RuleClass; |
| import com.google.devtools.build.lib.packages.Target; |
| import com.google.devtools.build.lib.packages.Type; |
| import com.google.devtools.build.lib.util.OrderedSetMultimap; |
| import java.util.HashSet; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| import javax.annotation.Nullable; |
| import net.starlark.java.syntax.Location; |
| |
| /** |
| * Helpers for resolution for dependencies between configured targets. |
| * |
| * <p>Includes logic to determine all attribute dependencies and their associated labels. |
| */ |
| public final class DependencyResolutionHelpers { |
| |
| private DependencyResolutionHelpers() {} |
| |
| /** The tuple {@link #computeDependencyLabels} outputs. */ |
| public static final class DependencyLabels { |
| private final OrderedSetMultimap<DependencyKind, Label> labels; |
| @Nullable private final ConfiguredAttributeMapper attributeMap; |
| |
| private DependencyLabels( |
| OrderedSetMultimap<DependencyKind, Label> labels, |
| @Nullable ConfiguredAttributeMapper attributeMap) { |
| this.labels = labels; |
| this.attributeMap = attributeMap; |
| } |
| |
| public OrderedSetMultimap<DependencyKind, Label> labels() { |
| return labels; |
| } |
| |
| @Nullable // Non-null for rules and output files when there are aspects that apply to files. |
| public ConfiguredAttributeMapper attributeMap() { |
| return attributeMap; |
| } |
| } |
| |
| public static DependencyLabels computeDependencyLabels( |
| TargetAndConfiguration node, |
| ImmutableList<Aspect> aspects, |
| ImmutableMap<Label, ConfigMatchingProvider> configConditions, |
| @Nullable ToolchainCollection<ToolchainContext> toolchainContexts) |
| throws Failure { |
| Target target = node.getTarget(); |
| BuildConfigurationValue config = node.getConfiguration(); |
| OrderedSetMultimap<DependencyKind, Label> outgoingLabels = OrderedSetMultimap.create(); |
| |
| // TODO(bazel-team): Figure out a way to implement the below using LabelVisitationUtils. |
| Rule fromRule; |
| ConfiguredAttributeMapper attributeMap = null; |
| if (target instanceof OutputFile) { |
| Preconditions.checkNotNull(config); |
| addVisibilityDepLabels(target.getVisibilityDependencyLabels(), outgoingLabels); |
| Rule rule = ((OutputFile) target).getGeneratingRule(); |
| outgoingLabels.put(OUTPUT_FILE_RULE_DEPENDENCY, rule.getLabel()); |
| if (Iterables.any(aspects, a -> a.getDefinition().applyToFiles())) { |
| attributeMap = ConfiguredAttributeMapper.of(rule, configConditions, config); |
| resolveAttributes(getAspectAttributes(aspects), outgoingLabels, rule, attributeMap, config); |
| } |
| addToolchainDeps(toolchainContexts, outgoingLabels); |
| } else if (target instanceof InputFile || target instanceof EnvironmentGroup) { |
| addVisibilityDepLabels(target.getVisibilityDependencyLabels(), outgoingLabels); |
| } else if (target instanceof Rule rule) { |
| fromRule = rule; |
| attributeMap = ConfiguredAttributeMapper.of(fromRule, configConditions, config); |
| visitRule(node, aspects, attributeMap, toolchainContexts, outgoingLabels); |
| } else if (target instanceof PackageGroup packageGroup) { |
| outgoingLabels.putAll(VISIBILITY_DEPENDENCY, packageGroup.getIncludes()); |
| } else { |
| throw new IllegalStateException(target.getLabel().toString()); |
| } |
| return new DependencyLabels(outgoingLabels, attributeMap); |
| } |
| |
| /** The results of {@link #getExecutionPlatformLabel} as a tagged union. */ |
| @AutoOneOf(DependencyResolutionHelpers.ExecutionPlatformResult.Kind.class) |
| public abstract static class ExecutionPlatformResult { |
| /** Tags for the possible results. */ |
| public enum Kind { |
| /** A label was successfully determined. */ |
| LABEL, |
| /** |
| * A label was successfully determined to be null. |
| * |
| * <p>{@link AutoOneOf} does not permit {@code @Nullable} so this is distinct from {@link |
| * #LABEL}. |
| */ |
| NULL_LABEL, |
| /** |
| * The dependency should be skipped. |
| * |
| * <p>See comments in {@link #getExecutionPlatformLabel} for details. |
| */ |
| SKIP, |
| /** An error message. */ |
| ERROR |
| } |
| |
| public abstract Kind kind(); |
| |
| public abstract Label label(); |
| |
| abstract void nullLabel(); |
| |
| abstract void skip(); |
| |
| public abstract String error(); |
| |
| private static ExecutionPlatformResult ofLabel(Label label) { |
| return AutoOneOf_DependencyResolutionHelpers_ExecutionPlatformResult.label(label); |
| } |
| |
| private static ExecutionPlatformResult ofNullLabel() { |
| return AutoOneOf_DependencyResolutionHelpers_ExecutionPlatformResult.nullLabel(); |
| } |
| |
| private static ExecutionPlatformResult ofSkip() { |
| return AutoOneOf_DependencyResolutionHelpers_ExecutionPlatformResult.skip(); |
| } |
| |
| private static ExecutionPlatformResult ofError(String message) { |
| return AutoOneOf_DependencyResolutionHelpers_ExecutionPlatformResult.error(message); |
| } |
| } |
| |
| public static ExecutionPlatformResult getExecutionPlatformLabel( |
| DependencyKind kind, |
| @Nullable ToolchainCollection<ToolchainContext> toolchainContexts, |
| ImmutableList<Aspect> aspectsList) { |
| if (toolchainContexts == null) { |
| return ExecutionPlatformResult.ofNullLabel(); |
| } |
| |
| TransitionFactory<AttributeTransitionData> transitionFactory = |
| kind.getAttribute().getTransitionFactory(); |
| if (!(transitionFactory instanceof ExecutionTransitionFactory)) { |
| return ExecutionPlatformResult.ofLabel( |
| toolchainContexts |
| .getToolchainContext(ExecGroup.DEFAULT_EXEC_GROUP_NAME) |
| .executionPlatform() |
| .label()); |
| } |
| |
| String execGroup = ((ExecutionTransitionFactory) transitionFactory).getExecGroup(); |
| if (toolchainContexts.hasToolchainContext(execGroup)) { |
| PlatformInfo platform = toolchainContexts.getToolchainContext(execGroup).executionPlatform(); |
| return platform == null |
| ? ExecutionPlatformResult.ofNullLabel() |
| : ExecutionPlatformResult.ofLabel(platform.label()); |
| } |
| |
| // `execGroup` could not be found. If `aspectsList` is non-empty, `toolchainContexts` only |
| // contains the exec groups of the main aspect. Skips the dependency if it's not the main |
| // aspect. |
| // |
| // TODO(b/256617733): Make a decision on whether the exec groups of the target and the base |
| // aspects should be merged in `toolchainContexts`. |
| if (!aspectsList.isEmpty() && !isMainAspect(aspectsList, kind.getOwningAspect())) { |
| return ExecutionPlatformResult.ofSkip(); |
| } |
| |
| return ExecutionPlatformResult.ofError( |
| String.format( |
| "Attr '%s' declares a transition for non-existent exec group '%s'", |
| kind.getAttribute().getName(), execGroup)); |
| } |
| |
| /** True if {@code owningAspect} is the main aspect, the last one in {@code aspectsList}. */ |
| private static boolean isMainAspect( |
| ImmutableList<Aspect> aspectsList, @Nullable AspectClass owningAspect) { |
| return Iterables.getLast(aspectsList).getAspectClass().equals(owningAspect); |
| } |
| |
| /** Indicates a failure during dependency resolution. */ |
| public static class Failure extends Exception { |
| @Nullable private final Location location; |
| |
| private Failure(Location location, String message) { |
| super(message); |
| this.location = location; |
| } |
| |
| /** Returns the location of the error, if known. */ |
| @Nullable |
| public Location getLocation() { |
| return location; |
| } |
| } |
| |
| private static void visitRule( |
| TargetAndConfiguration node, |
| ImmutableList<Aspect> aspects, |
| ConfiguredAttributeMapper attributeMap, |
| @Nullable ToolchainCollection<ToolchainContext> toolchainContexts, |
| OrderedSetMultimap<DependencyKind, Label> outgoingLabels) |
| throws Failure { |
| Preconditions.checkArgument(node.getTarget() instanceof Rule, node); |
| BuildConfigurationValue ruleConfig = Preconditions.checkNotNull(node.getConfiguration(), node); |
| Rule rule = (Rule) node.getTarget(); |
| |
| try { |
| attributeMap.validateAttributes(); |
| } catch (ConfiguredAttributeMapper.ValidationException ex) { |
| throw new Failure(rule.getLocation(), ex.getMessage()); |
| } |
| |
| Iterable<Label> visibilityDepLabels = rule.getVisibilityDependencyLabels(); |
| addVisibilityDepLabels(visibilityDepLabels, outgoingLabels); |
| resolveAttributes(getAttributes(rule, aspects), outgoingLabels, rule, attributeMap, ruleConfig); |
| |
| // Add the rule's visibility labels (which may come from the rule or from package defaults). |
| addExplicitDeps(outgoingLabels, rule, "visibility", visibilityDepLabels); |
| |
| // Add package default constraints when the rule doesn't explicitly declare them. |
| // |
| // Note that this can have subtle implications for constraint semantics. For example: say that |
| // package defaults declare compatibility with ':foo' and rule R declares compatibility with |
| // ':bar'. Does that mean that R is compatible with [':foo', ':bar'] or just [':bar']? In other |
| // words, did R's author intend to add additional compatibility to the package defaults or to |
| // override them? More severely, what if package defaults "restrict" support to just [':baz']? |
| // Should R's declaration signify [':baz'] + ['bar'], [ORIGINAL_DEFAULTS] + ['bar'], or |
| // something else? |
| // |
| // Rather than try to answer these questions with possibly confusing logic, we take the |
| // simple approach of assigning the rule's "restriction" attribute to the rule-declared value if |
| // it exists, else the package defaults value (and likewise for "compatibility"). This may not |
| // always provide what users want, but it makes it easy for them to understand how rule |
| // declarations and package defaults intermix (and how to refactor them to get what they want). |
| // |
| // An alternative model would be to apply the "rule declaration" / "rule class defaults" |
| // relationship, i.e. the rule class' "compatibility" and "restriction" declarations are merged |
| // to generate a set of default environments, then the rule's declarations are independently |
| // processed on top of that. This protects against obscure coupling behavior between |
| // declarations from wildly different places (e.g. it offers clear answers to the examples posed |
| // above). But within the scope of a single package it seems better to keep the model simple and |
| // make the user responsible for resolving ambiguities. |
| if (!rule.isAttributeValueExplicitlySpecified(RuleClass.COMPATIBLE_ENVIRONMENT_ATTR)) { |
| addExplicitDeps( |
| outgoingLabels, |
| rule, |
| RuleClass.COMPATIBLE_ENVIRONMENT_ATTR, |
| rule.getPackage().getPackageArgs().defaultCompatibleWith()); |
| } |
| if (!rule.isAttributeValueExplicitlySpecified(RuleClass.RESTRICTED_ENVIRONMENT_ATTR)) { |
| addExplicitDeps( |
| outgoingLabels, |
| rule, |
| RuleClass.RESTRICTED_ENVIRONMENT_ATTR, |
| rule.getPackage().getPackageArgs().defaultRestrictedTo()); |
| } |
| |
| addToolchainDeps(toolchainContexts, outgoingLabels); |
| } |
| |
| private static void addToolchainDeps( |
| ToolchainCollection<ToolchainContext> toolchainContexts, |
| OrderedSetMultimap<DependencyKind, Label> outgoingLabels) { |
| if (toolchainContexts != null) { |
| for (Map.Entry<String, ToolchainContext> entry : |
| toolchainContexts.getContextMap().entrySet()) { |
| outgoingLabels.putAll( |
| DependencyKind.forExecGroup(entry.getKey()), |
| entry.getValue().resolvedToolchainLabels()); |
| } |
| } |
| } |
| |
| private static void resolveAttributes( |
| Iterable<AttributeDependencyKind> attributeDependencyKinds, |
| OrderedSetMultimap<DependencyKind, Label> outgoingLabels, |
| Rule rule, |
| ConfiguredAttributeMapper attributeMap, |
| BuildConfigurationValue ruleConfig) { |
| for (AttributeDependencyKind dependencyKind : attributeDependencyKinds) { |
| Attribute attribute = dependencyKind.getAttribute(); |
| // Not only is resolving CONFIG_SETTING_DEPS_ATTRIBUTE deps here wasteful, since the only |
| // place they're used is in ConfiguredTargetFunction.getConfigConditions, but it actually |
| // breaks trimming as shown by |
| // FeatureFlagManualTrimmingTest#featureFlagInUnusedSelectBranchButNotInTransitiveConfigs_DoesNotError |
| // because it resolves a dep that trimming (correctly) doesn't account for because it's part |
| // of an unchosen select() branch. |
| if (attribute.getName().equals(RuleClass.CONFIG_SETTING_DEPS_ATTRIBUTE)) { |
| continue; |
| } |
| Type<?> type = attribute.getType(); |
| if (type == BuildType.OUTPUT |
| || type == BuildType.OUTPUT_LIST |
| || type == BuildType.NODEP_LABEL |
| || type == BuildType.NODEP_LABEL_LIST |
| || type == BuildType.GENQUERY_SCOPE_TYPE |
| || type == BuildType.GENQUERY_SCOPE_TYPE_LIST) { |
| // These types invoke visitLabels() so that they are reported in "bazel query" but do not |
| // create a dependency. Maybe it's better to remove that, but then the labels() query |
| // function would need to be rethought. |
| continue; |
| } |
| |
| resolveAttribute( |
| attribute, type, dependencyKind, outgoingLabels, rule, attributeMap, ruleConfig); |
| } |
| } |
| |
| private static <T> void resolveAttribute( |
| Attribute attribute, |
| Type<T> type, |
| AttributeDependencyKind dependencyKind, |
| OrderedSetMultimap<DependencyKind, Label> outgoingLabels, |
| Rule rule, |
| ConfiguredAttributeMapper attributeMap, |
| BuildConfigurationValue ruleConfig) { |
| T attributeValue = null; |
| if (attribute.isImplicit()) { |
| // Since the attributes that come from aspects do not appear in attributeMap, we have to get |
| // their values from somewhere else. This incidentally means that aspects attributes are not |
| // configurable. It would be nice if that wasn't the case, but we'd have to revamp how |
| // attribute mapping works, which is a large chunk of work. |
| if (dependencyKind.getOwningAspect() == null) { |
| attributeValue = attributeMap.get(attribute.getName(), type); |
| } else { |
| Object defaultValue = attribute.getDefaultValue(rule); |
| attributeValue = |
| type.cast( |
| defaultValue instanceof ComputedDefault computedDefault |
| ? computedDefault.getDefault(attributeMap) |
| : defaultValue); |
| } |
| } else if (attribute.isLateBound()) { |
| attributeValue = |
| type.cast(resolveLateBoundDefault(rule, attributeMap, attribute, ruleConfig)); |
| } else if (dependencyKind.getOwningAspect() == null && attributeMap.has(attribute.getName())) { |
| // This condition is false for aspect attributes that do not give rise to dependencies because |
| // attributes that come from aspects do not appear in attributeMap (see the comment in the |
| // case that handles implicit attributes). |
| attributeValue = attributeMap.get(attribute.getName(), type); |
| } |
| |
| if (attributeValue == null) { |
| return; |
| } |
| |
| type.visitLabels( |
| (depLabel, ctx) -> outgoingLabels.put(dependencyKind, depLabel), |
| attributeValue, |
| /*context=*/ null); |
| } |
| |
| @Nullable |
| @VisibleForTesting(/* used to test LateBoundDefaults' default values */ ) |
| static <FragmentT> Object resolveLateBoundDefault( |
| Rule rule, |
| AttributeMap attributeMap, |
| Attribute attribute, |
| BuildConfigurationValue ruleConfig) { |
| Preconditions.checkState(!attribute.getTransitionFactory().isSplit()); |
| @SuppressWarnings("unchecked") |
| LateBoundDefault<FragmentT, ?> lateBoundDefault = |
| (LateBoundDefault<FragmentT, ?>) attribute.getLateBoundDefault(); |
| |
| Class<FragmentT> fragmentClass = lateBoundDefault.getFragmentClass(); |
| // TODO(b/65746853): remove this when nothing uses it anymore |
| if (BuildConfigurationValue.class.equals(fragmentClass) |
| // noconfig targets can't meaningfully parse late-bound defaults. See NoConfigTransition. |
| && !ruleConfig.getOptions().hasNoConfig()) { |
| return lateBoundDefault.resolve(rule, attributeMap, fragmentClass.cast(ruleConfig)); |
| } |
| if (Void.class.equals(fragmentClass)) { |
| return lateBoundDefault.resolve(rule, attributeMap, null); |
| } |
| @SuppressWarnings("unchecked") |
| FragmentT fragment = |
| fragmentClass.cast(ruleConfig.getFragment((Class<? extends Fragment>) fragmentClass)); |
| if (fragment == null) { |
| return null; |
| } |
| return lateBoundDefault.resolve(rule, attributeMap, fragment); |
| } |
| |
| /** |
| * Adds new dependencies to the given rule under the given attribute name |
| * |
| * @param attrName the name of the attribute to add dependency labels to |
| * @param labels the dependencies to add |
| */ |
| private static void addExplicitDeps( |
| OrderedSetMultimap<DependencyKind, Label> outgoingLabels, |
| Rule rule, |
| String attrName, |
| Iterable<Label> labels) { |
| if (!rule.isAttrDefined(attrName, BuildType.LABEL_LIST) |
| && !rule.isAttrDefined(attrName, BuildType.NODEP_LABEL_LIST)) { |
| return; |
| } |
| Attribute attribute = rule.getRuleClassObject().getAttributeByName(attrName); |
| outgoingLabels.putAll(AttributeDependencyKind.forRule(attribute), labels); |
| } |
| |
| /** Returns the attributes that should be visited for this rule/aspect combination. */ |
| private static ImmutableList<AttributeDependencyKind> getAttributes( |
| Rule rule, ImmutableList<Aspect> aspects) { |
| ImmutableList.Builder<AttributeDependencyKind> result = ImmutableList.builder(); |
| HashSet<String> ruleAndBaseAspectsProcessedAttributes = new HashSet<>(); |
| |
| // For aspects evaluation, all attributes of the main aspect (last aspect in {@code aspects} |
| // should be added, even if they have the same name as an attribute in the rule or a base aspect |
| // because main aspect attributes are separated and retrieved from `ctx.attr`. |
| |
| // Attributes of the underlying rule and base aspects are merged and retrieved from |
| // `ctx.rule.attr` with rule attributes taking precedence then aspects' attributes based on the |
| // aspect order in the aspects path (lowest order to highest). |
| |
| List<Attribute> ruleAttributes = rule.getRuleClassObject().getAttributes(); |
| for (Attribute attribute : ruleAttributes) { |
| result.add(AttributeDependencyKind.forRule(attribute)); |
| ruleAndBaseAspectsProcessedAttributes.add(attribute.getName()); |
| } |
| |
| addAspectAttributes(aspects, ruleAndBaseAspectsProcessedAttributes, result); |
| |
| return result.build(); |
| } |
| |
| private static ImmutableList<AttributeDependencyKind> getAspectAttributes( |
| ImmutableList<Aspect> aspects) { |
| ImmutableList.Builder<AttributeDependencyKind> result = ImmutableList.builder(); |
| addAspectAttributes(aspects, new HashSet<>(), result); |
| return result.build(); |
| } |
| |
| private static void addAspectAttributes( |
| ImmutableList<Aspect> aspects, |
| Set<String> processedAttributes, |
| ImmutableList.Builder<AttributeDependencyKind> attributes) { |
| |
| if (aspects.isEmpty()) { |
| return; |
| } |
| |
| // Add all the main aspect's attributes |
| Aspect mainAspect = Iterables.getLast(aspects, null); |
| for (Attribute attribute : mainAspect.getDefinition().getAttributes().values()) { |
| attributes.add(AttributeDependencyKind.forAspect(attribute, mainAspect.getAspectClass())); |
| } |
| |
| // For base aspects, if multiple attributes have the same name, take the first encountered in |
| // the aspects path. |
| for (Aspect aspect : aspects.subList(0, aspects.size() - 1)) { |
| for (Attribute attribute : aspect.getDefinition().getAttributes().values()) { |
| if (processedAttributes.add(attribute.getName())) { |
| attributes.add(AttributeDependencyKind.forAspect(attribute, aspect.getAspectClass())); |
| } |
| } |
| } |
| } |
| |
| private static void addVisibilityDepLabels( |
| Iterable<Label> labels, OrderedSetMultimap<DependencyKind, Label> outgoingLabels) { |
| outgoingLabels.putAll(VISIBILITY_DEPENDENCY, labels); |
| } |
| } |
