[parsing] Fix maybe-assigned flag in some cases.

[parsing] Fix maybe-assigned flag in some cases.

This CL attempts to set the maybe-assigned flag for variables that are written
to as part of a destructuring or loop header.

For instance, in the following two cases we now mark x as maybe-assigned.

a) [x] = [1];
b) for (x of [1,2,3]) {};

There's more work to do here, this is just a first step.

R=adamk@chromium.org, mstarzinger@chromium.org
BUG=v8:5636
Committed: https://crrev.com/fcb7591520e9a8dc3fd7e535233ab064d6ba044e
Cr-Commit-Position: refs/heads/master@{#41582}

[adamk, 2016-12-07 17:41:17]

lgtm

[neis, 2016-12-08 08:15:17]

The CQ bit was checked by neis@chromium.org

[commit-bot: I haz the power, 2016-12-08 08:15:27]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-12-08 08:15:28]

This CL has an open dependency (Issue 2554363002 Patch 1). Please resolve the
dependency and try again.
If you are sure that there is no real dependency, please use one of the options
listed in https://goo.gl/9Es4OR to land the CL.

[neis, 2016-12-08 08:58:55]

The CQ bit was checked by neis@chromium.org

[neis, 2016-12-08 08:58:56]

The patchset sent to the CQ was uploaded after l-g-t-m from adamk@chromium.org
Link to the patchset: https://codereview.chromium.org/2562443003/#ps40001
(title: "rebase")

[commit-bot: I haz the power, 2016-12-08 08:58:57]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-12-08 09:24:51]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-12-08 09:24:52]

Failed to apply patch for src/parsing/parser.cc:
While running git apply --index -p1;
  error: patch failed: src/parsing/parser.cc:2069
  error: src/parsing/parser.cc: patch does not apply

Patch:       src/parsing/parser.cc
Index: src/parsing/parser.cc
diff --git a/src/parsing/parser.cc b/src/parsing/parser.cc
index
ebe17b2a75e07782a74efe4c2beaac1d9c937d56..d68b2d37f8bea087b16177189612254ce39c9c71
100644
--- a/src/parsing/parser.cc
+++ b/src/parsing/parser.cc
@@ -1920,6 +1920,7 @@ Statement*
Parser::InitializeForEachStatement(ForEachStatement* stmt,
       body = block;
       each = factory()->NewVariableProxy(temp);
     }
+    MarkExpressionAsAssigned(each);
     stmt->AsForInStatement()->Initialize(each, subject, body);
   }
   return stmt;
@@ -2069,8 +2070,8 @@ Statement*
Parser::InitializeForOfStatement(ForOfStatement* for_of,
   const int nopos = kNoSourcePosition;
   auto avfactory = ast_value_factory();
 
-  Variable* iterator =
NewTemporary(ast_value_factory()->dot_iterator_string());
-  Variable* result = NewTemporary(ast_value_factory()->dot_result_string());
+  Variable* iterator = NewTemporary(avfactory->dot_iterator_string());
+  Variable* result = NewTemporary(avfactory->dot_result_string());
   Variable* completion = NewTemporary(avfactory->empty_string());
 
   // iterator = iterable[Symbol.iterator]()

[neis, 2016-12-08 09:26:17]

The CQ bit was checked by neis@chromium.org

[commit-bot: I haz the power, 2016-12-08 09:26:25]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-12-08 09:28:00]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-12-08 09:28:01]

Failed to apply patch for src/parsing/parser.cc:
While running git apply --index -p1;
  error: patch failed: src/parsing/parser.cc:2069
  error: src/parsing/parser.cc: patch does not apply

Patch:       src/parsing/parser.cc
Index: src/parsing/parser.cc
diff --git a/src/parsing/parser.cc b/src/parsing/parser.cc
index
ebe17b2a75e07782a74efe4c2beaac1d9c937d56..d68b2d37f8bea087b16177189612254ce39c9c71
100644
--- a/src/parsing/parser.cc
+++ b/src/parsing/parser.cc
@@ -1920,6 +1920,7 @@ Statement*
Parser::InitializeForEachStatement(ForEachStatement* stmt,
       body = block;
       each = factory()->NewVariableProxy(temp);
     }
+    MarkExpressionAsAssigned(each);
     stmt->AsForInStatement()->Initialize(each, subject, body);
   }
   return stmt;
@@ -2069,8 +2070,8 @@ Statement*
Parser::InitializeForOfStatement(ForOfStatement* for_of,
   const int nopos = kNoSourcePosition;
   auto avfactory = ast_value_factory();
 
-  Variable* iterator =
NewTemporary(ast_value_factory()->dot_iterator_string());
-  Variable* result = NewTemporary(ast_value_factory()->dot_result_string());
+  Variable* iterator = NewTemporary(avfactory->dot_iterator_string());
+  Variable* result = NewTemporary(avfactory->dot_result_string());
   Variable* completion = NewTemporary(avfactory->empty_string());
 
   // iterator = iterable[Symbol.iterator]()

[neis, 2016-12-08 09:36:55]

The CQ bit was checked by neis@chromium.org

[neis, 2016-12-08 09:36:56]

The patchset sent to the CQ was uploaded after l-g-t-m from adamk@chromium.org
Link to the patchset: https://codereview.chromium.org/2562443003/#ps60001
(title: "rebase again???")

[commit-bot: I haz the power, 2016-12-08 09:37:01]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Michael Starzinger, 2016-12-08 09:48:10]

LGTM.

[commit-bot: I haz the power, 2016-12-08 10:05:43]

CQ is committing da patch.

Bot data: {"patchset_id": 60001, "attempt_start_ts": 1481189815731480,
"parent_rev": "5139b7402a8d0f4d7350a8ad9cd1acaa150b4e65", "commit_rev":
"b524cd5da631272b633763114a2c55c8ce7e9180"}

[commit-bot: I haz the power, 2016-12-08 10:05:52]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2016-12-08 10:06:17]

Description was changed from

==========
[parsing] Fix maybe-assigned flag in some cases.

This CL attempts to set the maybe-assigned flag for variables that are written
to as part of a destructuring or loop header.

For instance, in the following two cases we now mark x as maybe-assigned.

a) [x] = [1];
b) for (x of [1,2,3]) {};

There's more work to do here, this is just a first step.

R=adamk@chromium.org, mstarzinger@chromium.org
BUG=v8:5636
==========

to

==========
[parsing] Fix maybe-assigned flag in some cases.

This CL attempts to set the maybe-assigned flag for variables that are written
to as part of a destructuring or loop header.

For instance, in the following two cases we now mark x as maybe-assigned.

a) [x] = [1];
b) for (x of [1,2,3]) {};

There's more work to do here, this is just a first step.

R=adamk@chromium.org, mstarzinger@chromium.org
BUG=v8:5636

Committed: https://crrev.com/fcb7591520e9a8dc3fd7e535233ab064d6ba044e
Cr-Commit-Position: refs/heads/master@{#41582}
==========

[commit-bot: I haz the power, 2016-12-08 10:06:20]

Patchset 4 (id:??) landed as
https://crrev.com/fcb7591520e9a8dc3fd7e535233ab064d6ba044e
Cr-Commit-Position: refs/heads/master@{#41582}