PreParsing inner funcs: Remove nonsense code from PreParser.

The assignment in default parameters (e.g., function foo(a = somedefault) { }
doesn't flow through PreParserFactory::NewAssignment even if the comment claims so.
Thus, piping through the variables is not needed.

Kudos to neis@ for pointing this out.

BUG=v8:5501
R=neis@chromium.org

Review-Url: https://codereview.chromium.org/2569983003
Cr-Commit-Position: refs/heads/master@{#41670}

src/parsing/preparser.h

@@ -156,10 +156,9 @@ class PreParserExpression {
     return PreParserExpression(TypeField::encode(kExpression));
   }
 
-  static PreParserExpression Assignment(ZoneList<VariableProxy*>* variables) {
+  static PreParserExpression Assignment() {
     return PreParserExpression(TypeField::encode(kExpression) |
-                                   ExpressionTypeField::encode(kAssignment),
-                               variables);
+                               ExpressionTypeField::encode(kAssignment));
   }
 
   static PreParserExpression ObjectLiteral(
@@ -618,8 +617,7 @@ class PreParserFactory {
                                     PreParserExpression left,
                                     PreParserExpression right,
                                     int pos) {
-    // For tracking variables for parameters with a default value.
-    return PreParserExpression::Assignment(left.variables_);
+    return PreParserExpression::Assignment();
   }
   PreParserExpression NewYield(PreParserExpression generator_object,
                                PreParserExpression expression, int pos,

test/cctest/test-parsing.cc

@@ -8467,6 +8467,12 @@ TEST(NoPessimisticContextAllocation) {
       {"function inner() { var {my_var : a} = {my_var}; }", true},
       {"function inner() { let {my_var : a} = {my_var}; }", true},
       {"function inner() { const {my_var : a} = {my_var}; }", true},
+      {"function inner(a = my_var) { }", true},
+      {"function inner() { function inner2(a = my_var) { } }", true},
+      {"function inner({a} = {a: my_var}) { }", true},
+      {"function inner() { function inner2({a} = {a: my_var}) { } }", true},
+      {"function inner([a] = [my_var]) { }", true},
+      {"function inner() { function inner2([a] = [my_var]) { } }", true},
       // No pessimistic context allocation:
       {"function inner() { var my_var; my_var; }", false},
       {"function inner() { var my_var; }", false},
@@ -8485,35 +8491,66 @@ TEST(NoPessimisticContextAllocation) {
       {"function inner() { const {my_var} = {my_var: 3}; my_var; }", false},
       {"function inner(my_var) { my_var; }", false},
       {"function inner(my_var) { }", false},
+      {"function inner(my_var = 5) { my_var; }", false},
+      {"function inner(my_var = 5) { }", false},
       {"function inner(...my_var) { my_var; }", false},
       {"function inner(...my_var) { }", false},
       {"function inner([a, my_var, b]) { my_var; }", false},
       {"function inner([a, my_var, b]) { }", false},
+      {"function inner([a, my_var, b] = [1, 2, 3]) { my_var; }", false},
+      {"function inner([a, my_var, b] = [1, 2, 3]) { }", false},
       {"function inner({x: my_var}) { my_var; }", false},
       {"function inner({x: my_var}) { }", false},
+      {"function inner({x: my_var} = {x: 0}) { my_var; }", false},
+      {"function inner({x: my_var} = {x: 0}) { }", false},
       {"function inner({my_var}) { my_var; }", false},
       {"function inner({my_var}) { }", false},
+      {"function inner({my_var} = {my_var: 0}) { my_var; }", false},
+      {"function inner({my_var} = {my_var: 0}) { }", false},
       {"function inner() { function inner2(my_var) { my_var; } }", false},
       {"function inner() { function inner2(my_var) { } }", false},
+      {"function inner() { function inner2(my_var = 5) { my_var; } }", false},
+      {"function inner() { function inner2(my_var = 5) { } }", false},
       {"function inner() { function inner2(...my_var) { my_var; } }", false},
       {"function inner() { function inner2(...my_var) { } }", false},
       {"function inner() { function inner2([a, my_var, b]) { my_var; } }",
        false},
       {"function inner() { function inner2([a, my_var, b]) { } }", false},
+      {"function inner() { function inner2([a, my_var, b] = [1, 2, 3]) { "
+       "my_var; } }",
+       false},
+      {"function inner() { function inner2([a, my_var, b] = [1, 2, 3]) { } }",
+       false},
       {"function inner() { function inner2({x: my_var}) { my_var; } }", false},
       {"function inner() { function inner2({x: my_var}) { } }", false},
+      {"function inner() { function inner2({x: my_var} = {x: 0}) { my_var; } }",
+       false},
+      {"function inner() { function inner2({x: my_var} = {x: 0}) { } }", false},
       {"function inner() { function inner2({my_var}) { my_var; } }", false},
       {"function inner() { function inner2({my_var}) { } }", false},
+      {"function inner() { function inner2({my_var} = {my_var: 8}) { my_var; } "
+       "}",
+       false},
+      {"function inner() { function inner2({my_var} = {my_var: 8}) { } }",
+       false},
       {"my_var =>  my_var; ", false},
       {"my_var => { }", false},
+      {"(my_var = 5) =>  my_var; ", false},
+      {"(my_var = 5) => { }", false},
       {"(...my_var) =>  my_var;", false},
       {"(...my_var) => { }", false},
       {"([a, my_var, b]) => my_var;", false},
       {"([a, my_var, b]) => { }", false},
+      {"([a, my_var, b] = [1, 2, 3]) => my_var;", false},
+      {"([a, my_var, b] = [1, 2, 3]) => { }", false},
       {"({x: my_var}) => my_var;", false},
       {"({x: my_var}) => { }", false},
+      {"({x: my_var} = {x: 0}) => my_var;", false},
+      {"({x: my_var} = {x: 0}) => { }", false},
       {"({my_var}) => my_var;", false},
       {"({my_var}) => { }", false},
+      {"({my_var} = {my_var: 5}) => my_var;", false},
+      {"({my_var} = {my_var: 5}) => { }", false},
       {"function inner() { try { } catch (my_var) { } }", false},
       {"function inner() { class my_var {}; }", false},
       // In the following cases we still context allocate pessimistically:
@@ -8525,16 +8562,24 @@ TEST(NoPessimisticContextAllocation) {
       {"function inner() { for (my_var of {}) { } }", true},
       {"function inner() { for (my_var in []) { my_var; } }", true},
       {"function inner() { for (my_var in []) { } }", true},
-      {"function inner() { my_var =>  my_var; }", true},
+      {"function inner() { my_var => my_var; }", true},
       {"function inner() { my_var => { }}", true},
-      {"function inner() { (...my_var) =>  my_var;}", true},
+      {"function inner() { (my_var = 5) => my_var; }", true},
+      {"function inner() { (my_var = 5) => { }}", true},
+      {"function inner() { (...my_var) => my_var;}", true},
       {"function inner() { (...my_var) => { }}", true},
       {"function inner() { ([a, my_var, b]) => my_var;}", true},
       {"function inner() { ([a, my_var, b]) => { }}", true},
+      {"function inner() { ([a, my_var, b] = [1, 2, 3]) => my_var;}", true},
+      {"function inner() { ([a, my_var, b] = [1, 2, 3]) => { }}", true},
       {"function inner() { ({x: my_var}) => my_var;}", true},
       {"function inner() { ({x: my_var}) => { }}", true},
+      {"function inner() { ({x: my_var} = {x: 0}) => my_var;}", true},
+      {"function inner() { ({x: my_var} = {x: 0}) => { }}", true},
       {"function inner() { ({my_var}) => my_var;}", true},
       {"function inner() { ({my_var}) => { }}", true},
+      {"function inner() { ({my_var} = {my_var: 5}) => my_var;}", true},
+      {"function inner() { ({my_var} = {my_var: 5}) => { }}", true},
       {"function inner() { class my_var {}; my_var }", true},
   };