Use the in-memory metadata in blaze as the source of truth for Fileset mappings

instead of the manifest files.

RELNOTES: None
PiperOrigin-RevId: 195149880

15 files changed, 250 insertions, 127 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionContext.java b/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionContext.java
index cd5085d947..c67645d41b 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionContext.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionContext.java
@@ -15,6 +15,7 @@
 package com.google.devtools.build.lib.actions;
 
 import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.eventbus.EventBus;
 import com.google.devtools.build.lib.actions.Artifact.ArtifactExpander;
@@ -27,6 +28,7 @@ import com.google.devtools.build.lib.events.ExtendedEventHandler;
 import com.google.devtools.build.lib.util.io.FileOutErr;
 import com.google.devtools.build.lib.vfs.FileSystem;
 import com.google.devtools.build.lib.vfs.Path;
+import com.google.devtools.build.lib.vfs.PathFragment;
 import com.google.devtools.build.skyframe.SkyFunction;
 import com.google.devtools.build.skyframe.SkyFunction.Environment;
 import com.google.devtools.common.options.OptionsClassProvider;
@@ -47,10 +49,14 @@ public class ActionExecutionContext implements Closeable {
   private final MetadataHandler metadataHandler;
   private final FileOutErr fileOutErr;
   private final ImmutableMap<String, String> clientEnv;
+  private final ImmutableMap<PathFragment, ImmutableList<FilesetOutputSymlink>>
+      inputFilesetMappings;
   private final ArtifactExpander artifactExpander;
   @Nullable
   private final Environment env;
 
+  @Nullable private ImmutableList<FilesetOutputSymlink> outputSymlinks;
+
   private ActionExecutionContext(
       Executor executor,
       ActionInputFileCache actionInputFileCache,
@@ -59,6 +65,7 @@ public class ActionExecutionContext implements Closeable {
       MetadataHandler metadataHandler,
       FileOutErr fileOutErr,
       Map<String, String> clientEnv,
+      ImmutableMap<PathFragment, ImmutableList<FilesetOutputSymlink>> inputFilesetMappings,
       @Nullable ArtifactExpander artifactExpander,
       @Nullable SkyFunction.Environment env) {
     this.actionInputFileCache = actionInputFileCache;
@@ -67,6 +74,7 @@ public class ActionExecutionContext implements Closeable {
     this.metadataHandler = metadataHandler;
     this.fileOutErr = fileOutErr;
     this.clientEnv = ImmutableMap.copyOf(clientEnv);
+    this.inputFilesetMappings = inputFilesetMappings;
     this.executor = executor;
     this.artifactExpander = artifactExpander;
     this.env = env;
@@ -80,6 +88,7 @@ public class ActionExecutionContext implements Closeable {
       MetadataHandler metadataHandler,
       FileOutErr fileOutErr,
       Map<String, String> clientEnv,
+      ImmutableMap<PathFragment, ImmutableList<FilesetOutputSymlink>> inputFilesetMappings,
       ArtifactExpander artifactExpander) {
     this(
         executor,
@@ -89,6 +98,7 @@ public class ActionExecutionContext implements Closeable {
         metadataHandler,
         fileOutErr,
         clientEnv,
+        inputFilesetMappings,
         artifactExpander,
         null);
   }
@@ -110,6 +120,7 @@ public class ActionExecutionContext implements Closeable {
         metadataHandler,
         fileOutErr,
         clientEnv,
+        ImmutableMap.of(),
         null,
         env);
   }
@@ -176,6 +187,24 @@ public class ActionExecutionContext implements Closeable {
     return executor.getEventHandler();
   }
 
+  public ImmutableMap<PathFragment, ImmutableList<FilesetOutputSymlink>> getInputFilesetMappings() {
+    return inputFilesetMappings;
+  }
+
+  @Nullable
+  public ImmutableList<FilesetOutputSymlink> getOutputSymlinks() {
+    return outputSymlinks;
+  }
+
+  public void setOutputSymlinks(ImmutableList<FilesetOutputSymlink> outputSymlinks) {
+    Preconditions.checkState(
+        this.outputSymlinks == null,
+        "Unexpected reassignment of the outputSymlinks of a Fileset from\n:%s to:\n%s",
+        this.outputSymlinks,
+        outputSymlinks);
+    this.outputSymlinks = outputSymlinks;
+  }
+
   /**
    * Looks up and returns an action context implementation of the given interface type.
    */
@@ -259,6 +288,7 @@ public class ActionExecutionContext implements Closeable {
         metadataHandler,
         fileOutErr,
         clientEnv,
+        inputFilesetMappings,
         artifactExpander,
         env);
   }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionContextFactory.java b/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionContextFactory.java
index 6a54212377..c3bcb092a7 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionContextFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionContextFactory.java
@@ -13,7 +13,10 @@
 // limitations under the License.
 package com.google.devtools.build.lib.actions;
 
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
 import com.google.devtools.build.lib.actions.cache.MetadataHandler;
+import com.google.devtools.build.lib.vfs.PathFragment;
 import java.util.Collection;
 import java.util.Map;
 
@@ -27,6 +30,9 @@ public interface ActionExecutionContextFactory {
    * Returns an action execution context. This involves creating a new FileOutErr, and it is the
    * caller's responsibility to close that, e.g. by calling {@link ActionExecutionContext#close}.
    */
-  ActionExecutionContext getContext(ActionInputFileCache graphFileCache,
-      MetadataHandler metadataHandler, Map<Artifact, Collection<Artifact>> expandedInputs);
+  ActionExecutionContext getContext(
+      ActionInputFileCache graphFileCache,
+      MetadataHandler metadataHandler,
+      Map<Artifact, Collection<Artifact>> expandedInputs,
+      ImmutableMap<PathFragment, ImmutableList<FilesetOutputSymlink>> inputFilesetMappings);
 }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/BaseSpawn.java b/src/main/java/com/google/devtools/build/lib/actions/BaseSpawn.java
index 437f4b1773..aa49f2f354 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/BaseSpawn.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/BaseSpawn.java
@@ -81,11 +81,6 @@ public class BaseSpawn implements Spawn {
   }
 
   @Override
-  public ImmutableList<Artifact> getFilesetManifests() {
-    return ImmutableList.<Artifact>of();
-  }
-
-  @Override
   public ImmutableList<String> getArguments() {
     // TODO(bazel-team): this method should be final, as the correct value of the args can be
     // injected in the ctor.
@@ -93,6 +88,11 @@ public class BaseSpawn implements Spawn {
   }
 
   @Override
+  public ImmutableMap<PathFragment, ImmutableList<FilesetOutputSymlink>> getFilesetMappings() {
+    return ImmutableMap.of();
+  }
+
+  @Override
   public ImmutableMap<String, String> getEnvironment() {
     PathFragment runfilesRoot = getRunfilesRoot();
     if (runfilesRoot == null
diff --git a/src/main/java/com/google/devtools/build/lib/actions/DelegateSpawn.java b/src/main/java/com/google/devtools/build/lib/actions/DelegateSpawn.java
index eb09c6ee8e..3b6447a9f8 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/DelegateSpawn.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/DelegateSpawn.java
@@ -17,6 +17,7 @@ package com.google.devtools.build.lib.actions;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
+import com.google.devtools.build.lib.vfs.PathFragment;
 import java.util.Collection;
 import javax.annotation.Nullable;
 
@@ -38,11 +39,6 @@ public class DelegateSpawn implements Spawn {
   }
 
   @Override
-  public ImmutableList<Artifact> getFilesetManifests() {
-    return spawn.getFilesetManifests();
-  }
-
-  @Override
   public RunfilesSupplier getRunfilesSupplier() {
     return spawn.getRunfilesSupplier();
   }
@@ -58,6 +54,11 @@ public class DelegateSpawn implements Spawn {
   }
 
   @Override
+  public ImmutableMap<PathFragment, ImmutableList<FilesetOutputSymlink>> getFilesetMappings() {
+    return spawn.getFilesetMappings();
+  }
+
+  @Override
   public Iterable<? extends ActionInput> getToolFiles() {
     return spawn.getToolFiles();
   }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/SimpleSpawn.java b/src/main/java/com/google/devtools/build/lib/actions/SimpleSpawn.java
index 4daffaf209..c5abd15869 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/SimpleSpawn.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/SimpleSpawn.java
@@ -18,6 +18,8 @@ import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
+import com.google.devtools.build.lib.vfs.PathFragment;
+import java.util.Map;
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 
@@ -34,7 +36,7 @@ public final class SimpleSpawn implements Spawn {
   private final ImmutableList<? extends ActionInput> inputs;
   private final ImmutableList<? extends ActionInput> tools;
   private final RunfilesSupplier runfilesSupplier;
-  private final ImmutableList<Artifact> filesetManifests;
+  private final Map<PathFragment, ImmutableList<FilesetOutputSymlink>> filesetMappings;
   private final ImmutableList<? extends ActionInput> outputs;
   private final ResourceSet localResources;
 
@@ -44,9 +46,9 @@ public final class SimpleSpawn implements Spawn {
       ImmutableMap<String, String> environment,
       ImmutableMap<String, String> executionInfo,
       RunfilesSupplier runfilesSupplier,
+      Map<PathFragment, ImmutableList<FilesetOutputSymlink>> filesetMappings,
       ImmutableList<? extends ActionInput> inputs,
       ImmutableList<? extends ActionInput> tools,
-      ImmutableList<Artifact> filesetManifests,
       ImmutableList<? extends ActionInput> outputs,
       ResourceSet localResources) {
     this.owner = Preconditions.checkNotNull(owner);
@@ -57,7 +59,7 @@ public final class SimpleSpawn implements Spawn {
     this.tools = Preconditions.checkNotNull(tools);
     this.runfilesSupplier =
         runfilesSupplier == null ? EmptyRunfilesSupplier.INSTANCE : runfilesSupplier;
-    this.filesetManifests = Preconditions.checkNotNull(filesetManifests);
+    this.filesetMappings = filesetMappings;
     this.outputs = Preconditions.checkNotNull(outputs);
     this.localResources = Preconditions.checkNotNull(localResources);
   }
@@ -76,9 +78,9 @@ public final class SimpleSpawn implements Spawn {
         environment,
         executionInfo,
         null,
+        ImmutableMap.of(),
         inputs,
         ImmutableList.<Artifact>of(),
-        ImmutableList.<Artifact>of(),
         outputs,
         localResources);
   }
@@ -94,11 +96,6 @@ public final class SimpleSpawn implements Spawn {
   }
 
   @Override
-  public ImmutableList<Artifact> getFilesetManifests() {
-    return filesetManifests;
-  }
-
-  @Override
   public ImmutableList<String> getArguments() {
     return arguments;
   }
@@ -109,6 +106,11 @@ public final class SimpleSpawn implements Spawn {
   }
 
   @Override
+  public ImmutableMap<PathFragment, ImmutableList<FilesetOutputSymlink>> getFilesetMappings() {
+    return ImmutableMap.copyOf(filesetMappings);
+  }
+
+  @Override
   public ImmutableList<? extends ActionInput> getInputFiles() {
     return inputs;
   }
diff --git a/src/main/java/com/google/devtools/build/lib/actions/Spawn.java b/src/main/java/com/google/devtools/build/lib/actions/Spawn.java
index 7e51517483..0440d22db5 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/Spawn.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/Spawn.java
@@ -17,6 +17,7 @@ package com.google.devtools.build.lib.actions;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
+import com.google.devtools.build.lib.vfs.PathFragment;
 import java.util.Collection;
 import javax.annotation.Nullable;
 
@@ -43,11 +44,6 @@ public interface Spawn {
   RunfilesSupplier getRunfilesSupplier();
 
   /**
-   * Returns artifacts for filesets, so they can be scheduled on remote execution.
-   */
-  ImmutableList<Artifact> getFilesetManifests();
-
-  /**
    * Returns the command (the first element) and its arguments.
    */
   ImmutableList<String> getArguments();
@@ -59,6 +55,12 @@ public interface Spawn {
   ImmutableMap<String, String> getEnvironment();
 
   /**
+   * Map of the execpath at which we expect the Fileset symlink trees, to a list of
+   * FilesetOutputSymlinks which contains the details of the Symlink trees.
+   */
+  ImmutableMap<PathFragment, ImmutableList<FilesetOutputSymlink>> getFilesetMappings();
+
+  /**
    * Returns the list of files that are required to execute this spawn (e.g. the compiler binary),
    * in contrast to files necessary for the tool to do its work (e.g. source code to be compiled).
    *
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java b/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java
index a7a56c32a7..77785abc12 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java
@@ -48,6 +48,7 @@ import com.google.devtools.build.lib.actions.CompositeRunfilesSupplier;
 import com.google.devtools.build.lib.actions.EmptyRunfilesSupplier;
 import com.google.devtools.build.lib.actions.ExecException;
 import com.google.devtools.build.lib.actions.ExecutionInfoSpecifier;
+import com.google.devtools.build.lib.actions.FilesetOutputSymlink;
 import com.google.devtools.build.lib.actions.ParamFileInfo;
 import com.google.devtools.build.lib.actions.ParameterFile;
 import com.google.devtools.build.lib.actions.ResourceSet;
@@ -340,10 +341,11 @@ public class SpawnAction extends AbstractAction implements ExecutionInfoSpecifie
    *
    * <p>This method is final, as it is merely a shorthand use of the generic way to obtain a spawn,
    * which also depends on the client environment. Subclasses that which to override the way to get
-   * a spawn should override {@link #getSpawn()} instead.
+   * a spawn should override the other GetSpawn() methods instead.
    */
   public final Spawn getSpawn() throws CommandLineExpansionException {
-    return new ActionSpawn(commandLines.allArguments(), null, ImmutableList.of());
+    return new ActionSpawn(
+        commandLines.allArguments(), null, ImmutableList.of(), ImmutableMap.of());
   }
 
   /**
@@ -353,17 +355,23 @@ public class SpawnAction extends AbstractAction implements ExecutionInfoSpecifie
   public Spawn getSpawn(ActionExecutionContext actionExecutionContext)
       throws CommandLineExpansionException {
     return getSpawn(
-        actionExecutionContext.getArtifactExpander(), actionExecutionContext.getClientEnv());
+        actionExecutionContext.getArtifactExpander(),
+        actionExecutionContext.getClientEnv(),
+        actionExecutionContext.getInputFilesetMappings());
   }
 
-  Spawn getSpawn(ArtifactExpander artifactExpander, Map<String, String> clientEnv)
+  Spawn getSpawn(
+      ArtifactExpander artifactExpander,
+      Map<String, String> clientEnv,
+      Map<PathFragment, ImmutableList<FilesetOutputSymlink>> filesetMappings)
       throws CommandLineExpansionException {
     ExpandedCommandLines expandedCommandLines =
         commandLines.expand(artifactExpander, getPrimaryOutput().getExecPath(), commandLineLimits);
     return new ActionSpawn(
         ImmutableList.copyOf(expandedCommandLines.arguments()),
         clientEnv,
-        expandedCommandLines.getParamFiles());
+        expandedCommandLines.getParamFiles(),
+        filesetMappings);
   }
 
   @Override
@@ -497,7 +505,7 @@ public class SpawnAction extends AbstractAction implements ExecutionInfoSpecifie
   private class ActionSpawn extends BaseSpawn {
 
     private final ImmutableList<ActionInput> inputs;
-    private final ImmutableList<Artifact> filesets;
+    private final Map<PathFragment, ImmutableList<FilesetOutputSymlink>> filesetMappings;
     private final ImmutableMap<String, String> effectiveEnvironment;
 
     /**
@@ -509,7 +517,8 @@ public class SpawnAction extends AbstractAction implements ExecutionInfoSpecifie
     private ActionSpawn(
         ImmutableList<String> arguments,
         Map<String, String> clientEnv,
-        Iterable<? extends ActionInput> additionalInputs) {
+        Iterable<? extends ActionInput> additionalInputs,
+        Map<PathFragment, ImmutableList<FilesetOutputSymlink>> filesetMappings) {
       super(
           arguments,
           ImmutableMap.<String, String>of(),
@@ -518,18 +527,15 @@ public class SpawnAction extends AbstractAction implements ExecutionInfoSpecifie
           SpawnAction.this,
           resourceSet);
       ImmutableList.Builder<ActionInput> inputs = ImmutableList.builder();
-      ImmutableList.Builder<Artifact> filesets = ImmutableList.builder();
       ImmutableList<Artifact> manifests = getRunfilesSupplier().getManifests();
       for (Artifact input : getInputs()) {
-        if (input.isFileset()) {
-          filesets.add(input);
-        } else if (!manifests.contains(input)) {
+        if (!input.isFileset() && !manifests.contains(input)) {
           inputs.add(input);
         }
       }
       inputs.addAll(additionalInputs);
-      this.filesets = filesets.build();
       this.inputs = inputs.build();
+      this.filesetMappings = filesetMappings;
       LinkedHashMap<String, String> env = new LinkedHashMap<>(SpawnAction.this.getEnvironment());
       if (clientEnv != null) {
         for (String var : SpawnAction.this.getClientEnvironmentVariables()) {
@@ -550,8 +556,8 @@ public class SpawnAction extends AbstractAction implements ExecutionInfoSpecifie
     }
 
     @Override
-    public ImmutableList<Artifact> getFilesetManifests() {
-      return filesets;
+    public ImmutableMap<PathFragment, ImmutableList<FilesetOutputSymlink>> getFilesetMappings() {
+      return ImmutableMap.copyOf(filesetMappings);
     }
 
     @Override
diff --git a/src/main/java/com/google/devtools/build/lib/exec/AbstractSpawnStrategy.java b/src/main/java/com/google/devtools/build/lib/exec/AbstractSpawnStrategy.java
index c516b7875a..d9ae236622 100644
--- a/src/main/java/com/google/devtools/build/lib/exec/AbstractSpawnStrategy.java
+++ b/src/main/java/com/google/devtools/build/lib/exec/AbstractSpawnStrategy.java
@@ -35,7 +35,6 @@ import com.google.devtools.build.lib.events.Event;
 import com.google.devtools.build.lib.exec.SpawnCache.CacheHandle;
 import com.google.devtools.build.lib.exec.SpawnRunner.ProgressStatus;
 import com.google.devtools.build.lib.exec.SpawnRunner.SpawnExecutionContext;
-import com.google.devtools.build.lib.rules.fileset.FilesetActionContext;
 import com.google.devtools.build.lib.util.CommandFailureUtils;
 import com.google.devtools.build.lib.util.io.FileOutErr;
 import com.google.devtools.build.lib.vfs.Path;
@@ -233,11 +232,11 @@ public abstract class AbstractSpawnStrategy implements SandboxedSpawnActionConte
     @Override
     public SortedMap<PathFragment, ActionInput> getInputMapping() throws IOException {
       if (lazyInputMapping == null) {
-        lazyInputMapping = spawnInputExpander.getInputMapping(
-            spawn,
-            actionExecutionContext.getArtifactExpander(),
-            actionExecutionContext.getActionInputFileCache(),
-            actionExecutionContext.getContext(FilesetActionContext.class));
+        lazyInputMapping =
+            spawnInputExpander.getInputMapping(
+                spawn,
+                actionExecutionContext.getArtifactExpander(),
+                actionExecutionContext.getActionInputFileCache());
       }
       return lazyInputMapping;
     }
diff --git a/src/main/java/com/google/devtools/build/lib/exec/FilesetManifest.java b/src/main/java/com/google/devtools/build/lib/exec/FilesetManifest.java
index 319ea6bfa8..05dee2b1b8 100644
--- a/src/main/java/com/google/devtools/build/lib/exec/FilesetManifest.java
+++ b/src/main/java/com/google/devtools/build/lib/exec/FilesetManifest.java
@@ -16,7 +16,7 @@ package com.google.devtools.build.lib.exec;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.google.common.io.LineProcessor;
-import com.google.devtools.build.lib.actions.Artifact;
+import com.google.devtools.build.lib.actions.FilesetOutputSymlink;
 import com.google.devtools.build.lib.analysis.AnalysisUtils;
 import com.google.devtools.build.lib.vfs.FileSystemUtils;
 import com.google.devtools.build.lib.vfs.Path;
@@ -25,6 +25,7 @@ import java.io.IOException;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -52,19 +53,6 @@ public final class FilesetManifest {
   }
 
   public static FilesetManifest parseManifestFile(
-      Artifact manifest,
-      Path execRoot,
-      String workspaceName,
-      RelativeSymlinkBehavior relSymlinkBehavior)
-          throws IOException {
-    return parseManifestFile(
-        manifest.getExecPath(),
-        execRoot,
-        workspaceName,
-        relSymlinkBehavior);
-  }
-
-  public static FilesetManifest parseManifestFile(
       PathFragment manifest,
       Path execRoot,
       String workspaceName,
@@ -82,13 +70,29 @@ public final class FilesetManifest {
     }
   }
 
+  public static FilesetManifest constructFilesetManifest(
+      List<FilesetOutputSymlink> outputSymlinks,
+      PathFragment targetPrefix,
+      RelativeSymlinkBehavior relSymlinkbehavior)
+      throws IOException {
+    LinkedHashMap<PathFragment, String> entries = new LinkedHashMap<>();
+    Map<PathFragment, String> relativeLinks = new HashMap<>();
+    for (FilesetOutputSymlink outputSymlink : outputSymlinks) {
+      PathFragment fullLocation = targetPrefix.getRelative(outputSymlink.name);
+      String artifact = outputSymlink.target.getPathString();
+      artifact = artifact.isEmpty() ? null : artifact;
+      addSymlinkEntry(artifact, fullLocation, relSymlinkbehavior, entries, relativeLinks);
+    }
+    return constructFilesetManifest(entries, relativeLinks);
+  }
+
   private static final class ManifestLineProcessor implements LineProcessor<FilesetManifest> {
     private final String workspaceName;
     private final PathFragment targetPrefix;
     private final RelativeSymlinkBehavior relSymlinkBehavior;
 
     private int lineNum;
-    private final Map<PathFragment, String> entries = new LinkedHashMap<>();
+    private final LinkedHashMap<PathFragment, String> entries = new LinkedHashMap<>();
     private final Map<PathFragment, String> relativeLinks = new HashMap<>();
 
     ManifestLineProcessor(
@@ -134,44 +138,59 @@ public final class FilesetManifest {
       }
 
       PathFragment fullLocation = targetPrefix.getRelative(location);
-      if (!entries.containsKey(fullLocation)) {
-        boolean isRelativeSymlink = artifact != null && !artifact.startsWith("/");
-        if (isRelativeSymlink && relSymlinkBehavior.equals(RelativeSymlinkBehavior.ERROR)) {
-          throw new IOException(String.format("runfiles target is not absolute: %s", artifact));
-        }
-        if (!isRelativeSymlink
-            || relSymlinkBehavior.equals(RelativeSymlinkBehavior.RESOLVE)) {
-          entries.put(fullLocation, artifact);
-          if (artifact != null && !artifact.startsWith("/")) {
-            relativeLinks.put(fullLocation, artifact);
-          }
-        }
-      }
+      addSymlinkEntry(artifact, fullLocation, relSymlinkBehavior, entries, relativeLinks);
       return true;
     }
 
     @Override
     public FilesetManifest getResult() {
-      // Resolve relative symlinks if possible. Note that relativeLinks only contains entries in
-      // RESOLVE mode.
-      for (Map.Entry<PathFragment, String> e : relativeLinks.entrySet()) {
-        PathFragment location = e.getKey();
-        String value = e.getValue();
-        PathFragment actualLocation = location.getParentDirectory().getRelative(value);
-        String actual = entries.get(actualLocation);
-        boolean isActualAcceptable = actual == null || actual.startsWith("/");
-        if (!entries.containsKey(actualLocation) || !isActualAcceptable) {
-          throw new IllegalStateException(
-              String.format(
-                  "runfiles target '%s' is not absolute, and could not be resolved in the same "
-                  + "Fileset", value));
+      return constructFilesetManifest(entries, relativeLinks);
+    }
+  }
+
+  private static void addSymlinkEntry(
+      String artifact,
+      PathFragment fullLocation,
+      RelativeSymlinkBehavior relSymlinkBehavior,
+      LinkedHashMap<PathFragment, String> entries,
+      Map<PathFragment, String> relativeLinks)
+      throws IOException {
+    if (!entries.containsKey(fullLocation)) {
+      boolean isRelativeSymlink = artifact != null && !artifact.startsWith("/");
+      if (isRelativeSymlink && relSymlinkBehavior.equals(RelativeSymlinkBehavior.ERROR)) {
+        throw new IOException(String.format("runfiles target is not absolute: %s", artifact));
+      }
+      if (!isRelativeSymlink || relSymlinkBehavior.equals(RelativeSymlinkBehavior.RESOLVE)) {
+        entries.put(fullLocation, artifact);
+        if (artifact != null && !artifact.startsWith("/")) {
+          relativeLinks.put(fullLocation, artifact);
         }
-        entries.put(location, actual);
       }
-      return new FilesetManifest(entries);
     }
   }
 
+  private static FilesetManifest constructFilesetManifest(
+      Map<PathFragment, String> entries, Map<PathFragment, String> relativeLinks) {
+    // Resolve relative symlinks if possible. Note that relativeLinks only contains entries in
+    // RESOLVE mode.
+    for (Map.Entry<PathFragment, String> e : relativeLinks.entrySet()) {
+      PathFragment location = e.getKey();
+      String value = e.getValue();
+      PathFragment actualLocation = location.getParentDirectory().getRelative(value);
+      String actual = entries.get(actualLocation);
+      boolean isActualAcceptable = actual == null || actual.startsWith("/");
+      if (!entries.containsKey(actualLocation) || !isActualAcceptable) {
+        throw new IllegalStateException(
+            String.format(
+                "runfiles target '%s' is not absolute, and could not be resolved in the same "
+                    + "Fileset",
+                value));
+      }
+      entries.put(location, actual);
+    }
+    return new FilesetManifest(entries);
+  }
+
   private final Map<PathFragment, String> entries;
 
   private FilesetManifest(Map<PathFragment, String> entries) {
diff --git a/src/main/java/com/google/devtools/build/lib/exec/SpawnInputExpander.java b/src/main/java/com/google/devtools/build/lib/exec/SpawnInputExpander.java
index f57968984d..cff57d121f 100644
--- a/src/main/java/com/google/devtools/build/lib/exec/SpawnInputExpander.java
+++ b/src/main/java/com/google/devtools/build/lib/exec/SpawnInputExpander.java
@@ -17,16 +17,16 @@ import static com.google.devtools.build.lib.exec.FilesetManifest.RelativeSymlink
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
 import com.google.devtools.build.lib.actions.ActionInput;
 import com.google.devtools.build.lib.actions.ActionInputFileCache;
 import com.google.devtools.build.lib.actions.ActionInputHelper;
 import com.google.devtools.build.lib.actions.Artifact;
 import com.google.devtools.build.lib.actions.Artifact.ArtifactExpander;
+import com.google.devtools.build.lib.actions.FilesetOutputSymlink;
 import com.google.devtools.build.lib.actions.RunfilesSupplier;
 import com.google.devtools.build.lib.actions.Spawn;
-import com.google.devtools.build.lib.actions.cache.VirtualActionInput;
 import com.google.devtools.build.lib.actions.cache.VirtualActionInput.EmptyActionInput;
-import com.google.devtools.build.lib.rules.fileset.FilesetActionContext;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import java.io.IOException;
@@ -109,12 +109,13 @@ public class SpawnInputExpander {
    * Parses the fileset manifest file, adding to the inputMappings where appropriate. Lines
    * referring to directories are recursed.
    */
+  // TODO(kush): make tests use the method with in-memory fileset data.
   @VisibleForTesting
   void parseFilesetManifest(
       Map<PathFragment, ActionInput> inputMappings, Artifact manifest, String workspaceName)
       throws IOException {
     FilesetManifest filesetManifest =
-        FilesetManifest.parseManifestFile(manifest, execRoot, workspaceName, ERROR);
+        FilesetManifest.parseManifestFile(manifest.getExecPath(), execRoot, workspaceName, ERROR);
     for (Map.Entry<PathFragment, String> mapping : filesetManifest.getEntries().entrySet()) {
       String value = mapping.getValue();
       ActionInput artifact = value == null ? EMPTY_FILE : ActionInputHelper.fromPath(value);
@@ -122,6 +123,23 @@ public class SpawnInputExpander {
     }
   }
 
+  public void addFilesetManifests(
+      Map<PathFragment, ImmutableList<FilesetOutputSymlink>> filesetMappings,
+      Map<PathFragment, ActionInput> inputMappings)
+      throws IOException {
+    for (PathFragment manifestExecpath : filesetMappings.keySet()) {
+      ImmutableList<FilesetOutputSymlink> outputSymlinks = filesetMappings.get(manifestExecpath);
+      FilesetManifest filesetManifest =
+          FilesetManifest.constructFilesetManifest(outputSymlinks, manifestExecpath, ERROR);
+
+      for (Map.Entry<PathFragment, String> mapping : filesetManifest.getEntries().entrySet()) {
+        String value = mapping.getValue();
+        ActionInput artifact = value == null ? EMPTY_FILE : ActionInputHelper.fromPath(value);
+        addMapping(inputMappings, mapping.getKey(), artifact);
+      }
+    }
+  }
+
   private void addInputs(
       Map<PathFragment, ActionInput> inputMap, Spawn spawn, ArtifactExpander artifactExpander) {
     List<ActionInput> inputs =
@@ -134,34 +152,17 @@ public class SpawnInputExpander {
   /**
    * Convert the inputs of the given spawn to a map from exec-root relative paths to action inputs.
    * The returned map never contains {@code null} values; it uses {@link #EMPTY_FILE} for empty
-   * files, which is an instance of {@link VirtualActionInput}.
-   */
-  public SortedMap<PathFragment, ActionInput> getInputMapping(
-      Spawn spawn, ArtifactExpander artifactExpander, ActionInputFileCache actionInputFileCache,
-      FilesetActionContext filesetContext)
-          throws IOException {
-    return getInputMapping(
-        spawn,
-        artifactExpander,
-        actionInputFileCache,
-        filesetContext == null ? null : filesetContext.getWorkspaceName());
-  }
-
-  /**
-   * Convert the inputs of the given spawn to a map from exec-root relative paths to action inputs.
-   * In some cases, this generates empty files, for which it uses {@code null}.
+   * files, which is an instance of {@link
+   * com.google.devtools.build.lib.actions.cache.VirtualActionInput}.
    */
   public SortedMap<PathFragment, ActionInput> getInputMapping(
-      Spawn spawn, ArtifactExpander artifactExpander, ActionInputFileCache actionInputFileCache,
-      String workspaceName)
-          throws IOException {
+      Spawn spawn, ArtifactExpander artifactExpander, ActionInputFileCache actionInputFileCache)
+      throws IOException {
     TreeMap<PathFragment, ActionInput> inputMap = new TreeMap<>();
     addInputs(inputMap, spawn, artifactExpander);
     addRunfilesToInputs(
         inputMap, spawn.getRunfilesSupplier(), actionInputFileCache);
-    for (Artifact manifest : spawn.getFilesetManifests()) {
-      parseFilesetManifest(inputMap, manifest, workspaceName);
-    }
+    addFilesetManifests(spawn.getFilesetMappings(), inputMap);
     return inputMap;
   }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/exec/StandaloneTestStrategy.java b/src/main/java/com/google/devtools/build/lib/exec/StandaloneTestStrategy.java
index c1f04356cc..c1248a6e4b 100644
--- a/src/main/java/com/google/devtools/build/lib/exec/StandaloneTestStrategy.java
+++ b/src/main/java/com/google/devtools/build/lib/exec/StandaloneTestStrategy.java
@@ -124,9 +124,9 @@ public class StandaloneTestStrategy extends TestStrategy {
             ImmutableMap.copyOf(executionInfo),
             new RunfilesSupplierImpl(
                 runfilesDir.relativeTo(execRoot), action.getExecutionSettings().getRunfiles()),
+            ImmutableMap.of(),
             /*inputs=*/ ImmutableList.copyOf(action.getInputs()),
             /*tools=*/ ImmutableList.<Artifact>of(),
-            /*filesetManifests=*/ ImmutableList.<Artifact>of(),
             ImmutableList.copyOf(action.getSpawnOutputs()),
             localResourceUsage);
 
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/SpawnGccStrategy.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/SpawnGccStrategy.java
index 5d29cb7c5c..fe35d84f29 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/SpawnGccStrategy.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/SpawnGccStrategy.java
@@ -55,9 +55,9 @@ public class SpawnGccStrategy implements CppCompileActionContext {
             ImmutableMap.copyOf(action.getEnvironment()),
             ImmutableMap.copyOf(action.getExecutionInfo()),
             EmptyRunfilesSupplier.INSTANCE,
+            ImmutableMap.of(),
             ImmutableList.copyOf(inputs),
             /* tools= */ ImmutableList.of(),
-            /* filesetManifests= */ ImmutableList.of(),
             action.getOutputs().asList(),
             action.estimateResourceConsumptionLocal());
 
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ActionExecutionFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/ActionExecutionFunction.java
index 77f7254639..aca1c5c8a6 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ActionExecutionFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/ActionExecutionFunction.java
@@ -17,6 +17,7 @@ import com.google.common.base.Function;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Predicates;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Maps;
@@ -27,8 +28,10 @@ import com.google.devtools.build.lib.actions.ActionExecutionContext;
 import com.google.devtools.build.lib.actions.ActionExecutionException;
 import com.google.devtools.build.lib.actions.ActionLookupData;
 import com.google.devtools.build.lib.actions.ActionLookupValue;
+import com.google.devtools.build.lib.actions.ActionLookupValue.ActionLookupKey;
 import com.google.devtools.build.lib.actions.AlreadyReportedActionExecutionException;
 import com.google.devtools.build.lib.actions.Artifact;
+import com.google.devtools.build.lib.actions.FilesetOutputSymlink;
 import com.google.devtools.build.lib.actions.MissingInputFileException;
 import com.google.devtools.build.lib.actions.NotifyOnActionCacheHit;
 import com.google.devtools.build.lib.actions.PackageRootResolver;
@@ -223,8 +226,7 @@ public class ActionExecutionFunction implements SkyFunction, CompletionReceiver
    * @throws ActionExecutionFunctionException
    */
   @Nullable
-  private AllInputs collectInputs(Action action, Environment env)
-      throws ActionExecutionFunctionException, InterruptedException {
+  private AllInputs collectInputs(Action action, Environment env) throws InterruptedException {
     Iterable<Artifact> allKnownInputs = Iterables.concat(
         action.getInputs(), action.getRunfilesSupplier().getArtifacts());
     if (action.inputsDiscovered()) {
@@ -373,10 +375,16 @@ public class ActionExecutionFunction implements SkyFunction, CompletionReceiver
 
     if (state.token == null) {
       // We got a hit from the action cache -- no need to execute.
+      Preconditions.checkState(
+          !(action instanceof SkyframeAwareAction),
+          "Error, we're not re-executing a "
+              + "SkyframeAwareAction which should be re-executed unconditionally. Action: %s",
+          action);
       return new ActionExecutionValue(
           metadataHandler.getOutputArtifactData(),
           metadataHandler.getOutputTreeArtifactData(),
-          metadataHandler.getAdditionalOutputData());
+          metadataHandler.getAdditionalOutputData(),
+          /*outputSymlinks=*/ null);
     }
 
     // Delete the metadataHandler's cache of the action's outputs, since they are being deleted.
@@ -429,11 +437,35 @@ public class ActionExecutionFunction implements SkyFunction, CompletionReceiver
       metadataHandler.discardOutputMetadata();
     }
 
+    ImmutableMap.Builder<PathFragment, ImmutableList<FilesetOutputSymlink>> filesetMappings =
+        ImmutableMap.builder();
+    for (Artifact actionInput : action.getInputs()) {
+      if (!actionInput.isFileset()) {
+        continue;
+      }
+
+      ActionLookupKey filesetActionLookupKey = (ActionLookupKey) actionInput.getArtifactOwner();
+      // Index 0 for the Fileset ConfiguredTarget indicates the SkyframeFilesetManifestAction where
+      // we compute the fileset's outputSymlinks.
+      SkyKey filesetActionKey = ActionExecutionValue.key(filesetActionLookupKey, 0);
+      ActionExecutionValue filesetValue = (ActionExecutionValue) env.getValue(filesetActionKey);
+      if (filesetValue == null) {
+        // At this point skyframe does not guarantee that the filesetValue will be ready, since
+        // the current action does not directly depend on the outputs of the
+        // SkyframeFilesetManifestAction whose ActionExecutionValue (filesetValue) is needed here.
+        // TODO(kush): Get rid of this hack by making the outputSymlinks available in the Fileset
+        // artifact, which this action depends on, so its value will be guaranteed to be present.
+        return null;
+      }
+      filesetMappings.put(actionInput.getExecPath(), filesetValue.getOutputSymlinks());
+    }
+
     try (ActionExecutionContext actionExecutionContext =
         skyframeActionExecutor.getContext(
             perActionFileCache,
             metadataHandler,
-            Collections.unmodifiableMap(state.expandedArtifacts))) {
+            Collections.unmodifiableMap(state.expandedArtifacts),
+            filesetMappings.build())) {
       if (!state.hasExecutedAction()) {
         state.value =
             skyframeActionExecutor.executeAction(
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ActionExecutionValue.java b/src/main/java/com/google/devtools/build/lib/skyframe/ActionExecutionValue.java
index 105886a845..7c7150bffb 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ActionExecutionValue.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/ActionExecutionValue.java
@@ -17,10 +17,12 @@ import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.MoreObjects;
 import com.google.common.base.Objects;
 import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.devtools.build.lib.actions.ActionLookupData;
 import com.google.devtools.build.lib.actions.ActionLookupValue;
 import com.google.devtools.build.lib.actions.Artifact;
+import com.google.devtools.build.lib.actions.FilesetOutputSymlink;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe;
 import com.google.devtools.build.skyframe.SkyKey;
@@ -63,22 +65,27 @@ public class ActionExecutionValue implements SkyValue {
    */
   private final ImmutableMap<Artifact, FileArtifactValue> additionalOutputData;
 
+  @Nullable private final ImmutableList<FilesetOutputSymlink> outputSymlinks;
+
   /**
    * @param artifactData Map from Artifacts to corresponding FileValues.
    * @param treeArtifactData All tree artifact data.
    * @param additionalOutputData Map from Artifacts to values if the FileArtifactValue for this
    *     artifact cannot be derived from the corresponding FileValue (see {@link
-   *     ActionMetadataHandler#getAdditionalOutputData} for when this is necessary).
-   *     These output data are not used by the {@link FilesystemValueChecker}
-   *     to invalidate ActionExecutionValues.
+   *     ActionMetadataHandler#getAdditionalOutputData} for when this is necessary). These output
+   *     data are not used by the {@link FilesystemValueChecker} to invalidate
+   *     ActionExecutionValues.
+   * @param outputSymlinks This represents the SymlinkTree which is the output of a fileset action.
    */
   ActionExecutionValue(
       Map<Artifact, FileValue> artifactData,
       Map<Artifact, TreeArtifactValue> treeArtifactData,
-      Map<Artifact, FileArtifactValue> additionalOutputData) {
+      Map<Artifact, FileArtifactValue> additionalOutputData,
+      @Nullable ImmutableList<FilesetOutputSymlink> outputSymlinks) {
     this.artifactData = ImmutableMap.<Artifact, FileValue>copyOf(artifactData);
     this.additionalOutputData = ImmutableMap.copyOf(additionalOutputData);
     this.treeArtifactData = ImmutableMap.copyOf(treeArtifactData);
+    this.outputSymlinks = outputSymlinks;
   }
 
   /**
@@ -124,6 +131,11 @@ public class ActionExecutionValue implements SkyValue {
     return treeArtifactData;
   }
 
+  @Nullable
+  ImmutableList<FilesetOutputSymlink> getOutputSymlinks() {
+    return outputSymlinks;
+  }
+
   /**
    * @param lookupKey A {@link SkyKey} whose argument is an {@code ActionLookupKey}, whose
    *     corresponding {@code ActionLookupValue} contains the action to be executed.
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeActionExecutor.java b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeActionExecutor.java
index 9fd7ce9e33..221fc9206d 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeActionExecutor.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeActionExecutor.java
@@ -17,6 +17,7 @@ import static com.google.devtools.build.lib.vfs.FileSystemUtils.createDirectoryA
 
 import com.google.common.base.Preconditions;
 import com.google.common.base.Throwables;
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Maps;
 import com.google.common.eventbus.EventBus;
@@ -55,6 +56,7 @@ import com.google.devtools.build.lib.actions.ArtifactPrefixConflictException;
 import com.google.devtools.build.lib.actions.CachedActionEvent;
 import com.google.devtools.build.lib.actions.EnvironmentalExecException;
 import com.google.devtools.build.lib.actions.Executor;
+import com.google.devtools.build.lib.actions.FilesetOutputSymlink;
 import com.google.devtools.build.lib.actions.MapBasedActionGraph;
 import com.google.devtools.build.lib.actions.MutableActionGraph;
 import com.google.devtools.build.lib.actions.MutableActionGraph.ActionConflictException;
@@ -481,8 +483,10 @@ public final class SkyframeActionExecutor implements ActionExecutionContextFacto
    */
   @Override
   public ActionExecutionContext getContext(
-      ActionInputFileCache graphFileCache, MetadataHandler metadataHandler,
-      Map<Artifact, Collection<Artifact>> expandedInputs) {
+      ActionInputFileCache graphFileCache,
+      MetadataHandler metadataHandler,
+      Map<Artifact, Collection<Artifact>> expandedInputs,
+      ImmutableMap<PathFragment, ImmutableList<FilesetOutputSymlink>> inputFilesetMappings) {
     FileOutErr fileOutErr = actionLogBufferPathGenerator.generate();
     return new ActionExecutionContext(
         executorEngine,
@@ -492,6 +496,7 @@ public final class SkyframeActionExecutor implements ActionExecutionContextFacto
         metadataHandler,
         fileOutErr,
         clientEnv,
+        inputFilesetMappings,
         new ArtifactExpanderImpl(expandedInputs));
   }
 
@@ -706,10 +711,18 @@ public final class SkyframeActionExecutor implements ActionExecutionContextFacto
             "%s %s", actionExecutionContext.getMetadataHandler(), metadataHandler);
         prepareScheduleExecuteAndCompleteAction(
             eventHandler, action, actionExecutionContext, actionStartTime, actionLookupData);
+        Preconditions.checkState(
+            actionExecutionContext.getOutputSymlinks() == null
+                || action instanceof SkyframeAwareAction,
+            "Unexpected to find outputSymlinks set"
+                + " in an action which is not a SkyframeAwareAction. Action: %s\n symlinks:%s",
+            action,
+            actionExecutionContext.getOutputSymlinks());
         return new ActionExecutionValue(
             metadataHandler.getOutputArtifactData(),
             metadataHandler.getOutputTreeArtifactData(),
-            metadataHandler.getAdditionalOutputData());
+            metadataHandler.getAdditionalOutputData(),
+            actionExecutionContext.getOutputSymlinks());
       } finally {
         profiler.completeTask(ProfilerTask.ACTION);
       }