Treat a '!' preceding a function literal as eager-compile hint.

src/parsing/parser-base.h

Index: src/parsing/parser-base.h
diff --git a/src/parsing/parser-base.h b/src/parsing/parser-base.h
index 4fe27e2e5a364a79c103051da3159938b991e21a..59e6afdd220b385645b3e751a2961ca275334ad8 100644
--- a/src/parsing/parser-base.h
+++ b/src/parsing/parser-base.h
@@ -460,12 +460,24 @@ class ParserBase {
       return next_function_is_parenthesized_;
     }
 
+    bool this_function_is_parenthesized() const {
+      return this_function_is_parenthesized_;
+    }
+
     void set_next_function_is_parenthesized(bool parenthesized) {
       next_function_is_parenthesized_ = parenthesized;
     }
 
-    bool this_function_is_parenthesized() const {
-      return this_function_is_parenthesized_;
+    bool next_function_is_exclaimed() const {
+      return next_function_is_exclaimed_;
+    }
+
+    bool this_function_is_exclaimed() const {
+      return this_function_is_exclaimed_;
+    }
+
+    void set_next_function_is_exclaimed(bool exclaimed) {
+      next_function_is_exclaimed_ = exclaimed;
     }
 
    private:
@@ -507,12 +519,14 @@ class ParserBase {
     ZoneList<typename ExpressionClassifier::Error> reported_errors_;
 
     // If true, the next (and immediately following) function literal is
-    // preceded by a parenthesis.
+    // preceded by a parenthesis / exclamation mark.
     bool next_function_is_parenthesized_;
+    bool next_function_is_exclaimed_;
 
-    // The value of the parents' next_function_is_parenthesized_, as it applies
+    // The value of the parents' next_function_is_*_, as it applies
     // to this function. Filled in by constructor.
     bool this_function_is_parenthesized_;
+    bool this_function_is_exclaimed_;
 
     friend Impl;
     friend class Checkpoint;
@@ -1464,12 +1478,17 @@ ParserBase<Impl>::FunctionState::FunctionState(
       non_patterns_to_rewrite_(0, scope->zone()),
       reported_errors_(16, scope->zone()),
       next_function_is_parenthesized_(false),
-      this_function_is_parenthesized_(false) {
+      next_function_is_exclaimed_(false),
+      this_function_is_parenthesized_(false),
+      this_function_is_exclaimed_(false) {
   *function_state_stack = this;
   if (outer_function_state_) {
     this_function_is_parenthesized_ =
         outer_function_state_->next_function_is_parenthesized_;
     outer_function_state_->next_function_is_parenthesized_ = false;
+    this_function_is_exclaimed_ =
+        outer_function_state_->next_function_is_exclaimed_;
+    outer_function_state_->next_function_is_exclaimed_ = false;
   }
 }
 
@@ -2941,6 +2960,11 @@ typename ParserBase<Impl>::ExpressionT ParserBase<Impl>::ParseUnaryExpression(
 
     op = Next();
     int pos = position();
+
+    // Record occurrence of "! function ..."
+    function_state_->set_next_function_is_exclaimed(op == Token::NOT &&
+                                                    peek() == Token::FUNCTION);
+
     ExpressionT expression = ParseUnaryExpression(CHECK_OK);
     impl()->RewriteNonPattern(CHECK_OK);