commit 68cc06bafa6d74ad44c3c1ec0c1724a9f42cb456
author nharmata <nharmata@google.com> Thu Mar 01 10:21:57 2018 -0800
committer Copybara-Service <copybara-piper@google.com> Thu Mar 01 10:23:49 2018 -0800
tree 8b3570f3a450e7e19b950cbb230a62a7c7465725
parent 13aac65751e684d2a89e31be25543a6a0e9d2978

Make the distinction between "global frame" and "lexical frame" explicit. As a nice consequence, this lets us reduce GC churn since we no longer need to create a frame instance for the lexical frame at a callsite of either a function when the environment is frozen or a builtin function (since builtins cannot modify bindings in their lexical frame).

RELNOTES: None
PiperOrigin-RevId: 187495787

src/main/java/com/google/devtools/build/lib/syntax/UserDefinedFunction.java

diff --git a/src/main/java/com/google/devtools/build/lib/syntax/UserDefinedFunction.java b/src/main/java/com/google/devtools/build/lib/syntax/UserDefinedFunction.java
index a7fcf19..b4fc95f 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/UserDefinedFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/UserDefinedFunction.java
@@ -19,6 +19,7 @@
 import com.google.devtools.build.lib.profiler.Profiler;
 import com.google.devtools.build.lib.profiler.ProfilerTask;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkPrinter;
+import com.google.devtools.build.lib.syntax.Environment.LexicalFrame;
 
 /**
  * The actual function registered in the environment. This function is defined in the
@@ -29,14 +30,14 @@
   private final ImmutableList<Statement> statements;
 
   // we close over the globals at the time of definition
-  private final Environment.Frame definitionGlobals;
+  private final Environment.GlobalFrame definitionGlobals;
 
   public UserDefinedFunction(
       String name,
       Location loc,
       FunctionSignature.WithValues<Object, SkylarkType> signature,
       ImmutableList<Statement> statements,
-      Environment.Frame definitionGlobals) {
+      Environment.GlobalFrame definitionGlobals) {
     super(name, signature, loc);
     this.statements = statements;
     this.definitionGlobals = definitionGlobals;
@@ -46,7 +47,7 @@
     return statements;
   }
 
-  public Environment.Frame getDefinitionGlobals() {
+  public Environment.GlobalFrame getDefinitionGlobals() {
     return definitionGlobals;
   }
 
@@ -64,7 +65,7 @@
 
     Profiler.instance().startTask(ProfilerTask.SKYLARK_USER_FN, getName());
     try {
-      env.enterScope(this, ast, definitionGlobals);
+      env.enterScope(this, LexicalFrame.create(env.mutability()), ast, definitionGlobals);
       ImmutableList<String> names = signature.getSignature().getNames();
 
       // Registering the functions's arguments as variables in the local Environment