A bunch of small changes to prepare SkyQueryEnvironment for full-parallel evaluation:

-Rename QueryExpression#evalConcurrently to QueryExpression#parEval. (parallelism is not concurrency! See https://existentialtype.wordpress.com/2011/03/17/parallelism-is-not-concurrency/)
-Have SkyQueryEnvironment#eval (used recursively in #evaluateQuery) dynamically call QueryExpression#parEval when appropriate.
-Delete QueryExpression#canEvalConcurrently.
-Add ThreadSafety annotations in a bunch of relevant places in the query codebase.
-A bunch of testing infrastructure to test parallel query evaluation.
-TODOs for implementing parallel evaluation of all QueryExpression nodes.

--
MOS_MIGRATED_REVID=132436340

1 files changed, 3 insertions, 2 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/query2/engine/TargetLiteral.java b/src/main/java/com/google/devtools/build/lib/query2/engine/TargetLiteral.java
index bb24022ee1..8b718ab01a 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/engine/TargetLiteral.java
+++ b/src/main/java/com/google/devtools/build/lib/query2/engine/TargetLiteral.java
@@ -45,8 +45,9 @@ public final class TargetLiteral extends QueryExpression {
   }
 
   @Override
-  public <T> void eval(QueryEnvironment<T> env, VariableContext<T> context, Callback<T> callback)
-      throws QueryException, InterruptedException {
+  protected <T> void evalImpl(
+      QueryEnvironment<T> env, VariableContext<T> context, Callback<T> callback)
+          throws QueryException, InterruptedException {
     if (isVariableReference()) {
       String varName = LetExpression.getNameFromReference(pattern);
       Set<T> value = context.get(varName);