Make --discard_analysis_cache work with Skymeld.

Until this CL, Skymeld has been disregarding --discard_analysis_cache.

PiperOrigin-RevId: 462130511
Change-Id: I0e6a183d73be1b228799cbb363226f9bc646075d

Author: joeleba

src/main/java/com/google/devtools/build/lib/analysis/BuildView.java

@@ -431,7 +431,9 @@ public AnalysisResult update(
                 checkForActionConflicts,
                 loadingPhaseThreads,
                 viewOptions.cpuHeavySkyKeysThreadPoolSize,
-                mergedPhasesExecutionJobsCount);
+                mergedPhasesExecutionJobsCount,
+                /*shouldDiscardAnalysisCache=*/ viewOptions.discardAnalysisCache
+                    || !skyframeExecutor.tracksStateForIncrementality());
       }
     } finally {
       skyframeBuildView.clearInvalidatedActionLookupKeys();

src/main/java/com/google/devtools/build/lib/skyframe/BuildDriverFunction.java

@@ -208,8 +208,8 @@ public SkyValue compute(SkyKey skyKey, Environment env)
           env,
           topLevelArtifactContext);
     } else {
-      env.getListener().post(TopLevelEntityAnalysisConcludedEvent.create(buildDriverKey));
-      requestAspectExecution((TopLevelAspectsValue) topLevelSkyValue, env, topLevelArtifactContext);
+      announceAspectAnalysisDoneAndRequestExecution(
+          buildDriverKey, (TopLevelAspectsValue) topLevelSkyValue, env, topLevelArtifactContext);
     }
 
     if (env.valuesMissing()) {
@@ -345,7 +345,8 @@ private void requestConfiguredTargetExecution(
     declareDependenciesAndCheckValues(env, artifactsToBuild.build());
   }
 
-  private void requestAspectExecution(
+  private void announceAspectAnalysisDoneAndRequestExecution(
+      BuildDriverKey buildDriverKey,
       TopLevelAspectsValue topLevelAspectsValue,
       Environment env,
       TopLevelArtifactContext topLevelArtifactContext)
@@ -362,6 +363,9 @@ private void requestAspectExecution(
       env.getListener().post(AspectAnalyzedEvent.create(aspectKey, configuredAspect));
       aspectCompletionKeys.add(AspectCompletionKey.create(aspectKey, topLevelArtifactContext));
     }
+    // Send the AspectAnalyzedEvents first to make sure the BuildResultListener is up-to-date before
+    // signaling that the analysis of this top level aspect has concluded.
+    env.getListener().post(TopLevelEntityAnalysisConcludedEvent.create(buildDriverKey));
 
     declareDependenciesAndCheckValues(
         env, Iterables.concat(artifactsToBuild.build(), aspectCompletionKeys));

src/main/java/com/google/devtools/build/lib/skyframe/SkyframeBuildView.java

@@ -362,7 +362,9 @@ public void clearAnalysisCache(
       ImmutableSet<ConfiguredTarget> topLevelTargets, ImmutableSet<AspectKey> topLevelAspects) {
     // TODO(bazel-team): Consider clearing packages too to save more memory.
     skyframeAnalysisWasDiscarded = true;
-    skyframeExecutor.clearAnalysisCache(topLevelTargets, topLevelAspects);
+    try (SilentCloseable c = Profiler.instance().profile("skyframeExecutor.clearAnalysisCache")) {
+      skyframeExecutor.clearAnalysisCache(topLevelTargets, topLevelAspects);
+    }
   }
 
   /**
@@ -633,7 +635,8 @@ public SkyframeAnalysisResult analyzeAndExecuteTargets(
       boolean checkForActionConflicts,
       int numThreads,
       int cpuHeavySkyKeysThreadPoolSize,
-      int mergedPhasesExecutionJobsCount)
+      int mergedPhasesExecutionJobsCount,
+      boolean shouldDiscardAnalysisCache)
       throws InterruptedException, ViewCreationFailedException, BuildFailedException,
           TestExecException {
     enableAnalysis(true);
@@ -683,14 +686,11 @@ public SkyframeAnalysisResult analyzeAndExecuteTargets(
             Sets.newConcurrentHashSet(Sets.union(buildDriverCTKeys, buildDriverAspectKeys)),
             eventBus,
             /*finisher=*/ () ->
-                eventBus.post(
-                    AnalysisPhaseCompleteEvent.fromSkymeld(
-                        buildResultListener.getAnalyzedTargets(),
-                        getEvaluatedCounts(),
-                        getEvaluatedActionCounts(),
-                        analysisWorkTimer.stop().elapsed().toMillis(),
-                        skyframeExecutor.getPackageManager().getAndClearStatistics(),
-                        skyframeExecutor.wasAnalysisCacheInvalidatedAndResetBit())))) {
+                analysisFinishedCallback(
+                    eventBus,
+                    buildResultListener,
+                    shouldDiscardAnalysisCache,
+                    /*measuredAnalysisTime=*/ analysisWorkTimer.stop().elapsed().toMillis()))) {
 
       try {
         resourceManager.resetResourceUsage();
@@ -814,6 +814,27 @@ public SkyframeAnalysisResult analyzeAndExecuteTargets(
     }
   }
 
+  /** Handles the required steps after all analysis work in this build is done. */
+  private void analysisFinishedCallback(
+      EventBus eventBus,
+      BuildResultListener buildResultListener,
+      boolean shouldDiscardAnalysisCache,
+      long measuredAnalysisTime) {
+    if (shouldDiscardAnalysisCache) {
+      clearAnalysisCache(
+          buildResultListener.getAnalyzedTargets(),
+          buildResultListener.getAnalyzedAspects().keySet());
+    }
+    eventBus.post(
+        AnalysisPhaseCompleteEvent.fromSkymeld(
+            buildResultListener.getAnalyzedTargets(),
+            getEvaluatedCounts(),
+            getEvaluatedActionCounts(),
+            measuredAnalysisTime,
+            skyframeExecutor.getPackageManager().getAndClearStatistics(),
+            skyframeExecutor.wasAnalysisCacheInvalidatedAndResetBit()));
+  }
+
   /**
    * Report the appropriate conflicts and return a TopLevelActionConflictReport.
    *