deps: v8, backport coverage fixes

Pulls in patches from V8 (52e2b5, 512175, aac2f8, 9365d09, 2d08967)
which address a variety of coverage bugs, bringing Node v10 coverage
to parity with Node v11.

  Original commit message:

    [coverage] Extend SourceRangeAstVisitor for throw statements

    The SourceRangeAstVisitor has custom logic for blocks ending with a
    statement that has a continuation range. In these cases, the trailing
    continuation is removed which makes the reported coverage ranges a bit
    nicer.

    throw Error('foo') consists of an ExpressionStatement, with a
    Throw expression stored within the statement. The source range itself
    is stored with the Throw, not the statement.

    We now properly extract the correct AST node for trailing throw
    statements.

  R=jgruber@chromium.org, neis@chromium.org, yangguo@chromium.org

  Bug: v8:8691
  Change-Id: Ibcbab79fbe54719a8993045040349c863b139011
  Reviewed-on: https://chromium-review.googlesource.com/c/1480632
  Commit-Queue: Georg Neis <neis@chromium.org>
  Reviewed-by: Georg Neis <neis@chromium.org>
  Reviewed-by: Jakob Gruber <jgruber@chromium.org>
  Cr-Commit-Position: refs/heads/master@{#59936}

  Refs: v8/v8@2d08967

  Original commit message:

    [coverage] Rework continuation counter handling

    This changes a few bits about how continuation counters are handled.

    It introduces a new mechanism that allows removal of a continuation
    range after it has been created. If coverage is enabled, we run a first
    post-processing pass on the AST immediately after parsing, which
    removes problematic continuation ranges in two situations:

    1. nested continuation counters - only the outermost stays alive.
    2. trailing continuation counters within a block-like structure are
        removed if the containing structure itself has a continuation.

  R=bmeurer@chromium.org, jgruber@chromium.org, yangguo@chromium.org

  Bug: v8:8381, v8:8539
  Change-Id: I6bcaea5060d8c481d7bae099f6db9f993cc30ee3
  Reviewed-on: https://chromium-review.googlesource.com/c/1339119
  Reviewed-by: Yang Guo <yangguo@chromium.org>
  Reviewed-by: Leszek Swirski <leszeks@chromium.org>
  Reviewed-by: Georg Neis <neis@chromium.org>
  Commit-Queue: Jakob Gruber <jgruber@chromium.org>
  Cr-Commit-Position: refs/heads/master@{#58443}

  Refs: v8/v8@9365d09

  Original commit message:

    [coverage] Filter out singleton ranges that alias full ranges

    Block coverage is based on a system of ranges that can either have
    both a start and end position, or only a start position (so-called
    singleton ranges). When formatting coverage information, singletons
    are expanded until the end of the immediate full parent range. E.g.
    in:

    {0, 10}  // Full range.
    {5, -1}  // Singleton range.

    the singleton range is expanded to {5, 10}.

    Singletons are produced mostly for continuation counters that track
    whether we execute past a specific language construct.

    Unfortunately, continuation counters can turn up in spots that confuse
    our post-processing. For example:

    if (true) { ... block1 ... } else { ... block2 ... }

    If block1 produces a continuation counter, it could end up with the
    same start position as the else-branch counter. Since we merge
    identical blocks, the else-branch could incorrectly end up with an
    execution count of one.

    We need to avoid merging such cases. A full range should always take
    precedence over a singleton range; a singleton range should never
    expand to completely fill a full range. An additional post-processing
    pass ensures this.

    Bug: v8:8237
    Change-Id: Idb3ec7b2feddc0585313810b9c8be1e9f4ec64bf
    Reviewed-on: https://chromium-review.googlesource.com/c/1273095
    Reviewed-by: Georg Neis <neis@chromium.org>
    Reviewed-by: Yang Guo <yangguo@chromium.org>
    Commit-Queue: Jakob Gruber <jgruber@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#56531}

  Refs: v8/v8@aac2f8c

  Original commit message:

    [ast] Introduce ZonePtrList<T> typedef for ZoneList<T*>.

    This is a preliminary step before changing the way we store zone pointers
    in the zones.

    Bug: v8:7903, v8:7754
    Change-Id: I1e1af1823766c888ee0f8fe190f205f5b7e21973
    Reviewed-on: https://chromium-review.googlesource.com/1118887
    Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
    Reviewed-by: Marja Hölttä <marja@chromium.org>
    Reviewed-by: Camillo Bruni <cbruni@chromium.org>
    Commit-Queue: Igor Sheludko <ishell@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#54193}

  Refs: v8/v8@512175a

  Original commit message:

    [explicit isolates] Replace every Handle(T*) in parsing/

    Replace all but one Handle<T*>(T*) calls with ones that explicitly pass
    in an Isolate.

    Requires plumbing Isolate* through several Parser functions which
    previously avoided it because of worries about accessing the heap off
    the main thread. In all off-main-thread cases, isolate will be nullptr
    and every such function asserts with:
    DCHECK_EQ(parsing_on_main_thread_, isolate != nullptr);

    Also deletes unused function ParseInfo::ReopenHandlesInNewHandleScope.

    Bug: v8:7786
    Change-Id: I3dd9c49dcde49fdbcb684ba73f47a30d00fc495e
    Reviewed-on: https://chromium-review.googlesource.com/1087272
    Commit-Queue: Dan Elphick <delphick@chromium.org>
    Reviewed-by: Toon Verwaest <verwaest@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#53820}

  Refs: v8/v8@52e2b5a

PR-URL: #26579
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Ujjwal Sharma <usharma1998@gmail.com>
Reviewed-By: Shelley Vohr <codebytere@gmail.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Beth Griggs <Bethany.Griggs@uk.ibm.com>

Author: bcoe

common.gypi

@@ -33,7 +33,7 @@
 
     # Reset this number to 0 on major V8 upgrades.
     # Increment by one for each non-official patch applied to deps/v8.
-    'v8_embedder_string': '-node.51',
+    'v8_embedder_string': '-node.52',
 
     # Enable disassembler for `--print-code` v8 options
     'v8_enable_disassembler': 1,

deps/v8/AUTHORS

@@ -49,7 +49,7 @@ Andrew Paprocki <andrew@ishiboo.com>
 Andrei Kashcha <anvaka@gmail.com>
 Anna Henningsen <anna@addaleax.net>
 Bangfu Tao <bangfu.tao@samsung.com>
-Ben Coe <ben@npmjs.com>
+Ben Coe <bencoe@gmail.com>
 Ben Newman <ben@meteor.com>
 Ben Noordhuis <info@bnoordhuis.nl>
 Benjamin Tan <demoneaux@gmail.com>

deps/v8/BUILD.gn

@@ -1496,6 +1496,8 @@ v8_source_set("v8_base") {
     "src/ast/prettyprinter.h",
     "src/ast/scopes.cc",
     "src/ast/scopes.h",
+    "src/ast/source-range-ast-visitor.cc",
+    "src/ast/source-range-ast-visitor.h",
     "src/ast/variables.cc",
     "src/ast/variables.h",
     "src/bailout-reason.cc",

deps/v8/gypfiles/v8.gyp

@@ -516,6 +516,8 @@
         '../src/ast/prettyprinter.h',
         '../src/ast/scopes.cc',
         '../src/ast/scopes.h',
+        "../src/ast/source-range-ast-visitor.cc",
+        "../src/ast/source-range-ast-visitor.h",
         '../src/ast/variables.cc',
         '../src/ast/variables.h',
         '../src/bailout-reason.cc',

deps/v8/src/ast/ast-source-ranges.h

@@ -58,18 +58,24 @@ class AstNodeSourceRanges : public ZoneObject {
  public:
   virtual ~AstNodeSourceRanges() {}
   virtual SourceRange GetRange(SourceRangeKind kind) = 0;
+  virtual bool HasRange(SourceRangeKind kind) = 0;
+  virtual void RemoveContinuationRange() { UNREACHABLE(); }
 };
 
 class BinaryOperationSourceRanges final : public AstNodeSourceRanges {
  public:
   explicit BinaryOperationSourceRanges(const SourceRange& right_range)
       : right_range_(right_range) {}
 
-  SourceRange GetRange(SourceRangeKind kind) {
-    DCHECK_EQ(kind, SourceRangeKind::kRight);
+  SourceRange GetRange(SourceRangeKind kind) override {
+    DCHECK(HasRange(kind));
     return right_range_;
   }
 
+  bool HasRange(SourceRangeKind kind) override {
+    return kind == SourceRangeKind::kRight;
+  }
+
  private:
   SourceRange right_range_;
 };
@@ -79,11 +85,20 @@ class ContinuationSourceRanges : public AstNodeSourceRanges {
   explicit ContinuationSourceRanges(int32_t continuation_position)
       : continuation_position_(continuation_position) {}
 
-  SourceRange GetRange(SourceRangeKind kind) {
-    DCHECK_EQ(kind, SourceRangeKind::kContinuation);
+  SourceRange GetRange(SourceRangeKind kind) override {
+    DCHECK(HasRange(kind));
     return SourceRange::OpenEnded(continuation_position_);
   }
 
+  bool HasRange(SourceRangeKind kind) override {
+    return kind == SourceRangeKind::kContinuation;
+  }
+
+  void RemoveContinuationRange() override {
+    DCHECK(HasRange(SourceRangeKind::kContinuation));
+    continuation_position_ = kNoSourcePosition;
+  }
+
  private:
   int32_t continuation_position_;
 };
@@ -99,11 +114,15 @@ class CaseClauseSourceRanges final : public AstNodeSourceRanges {
   explicit CaseClauseSourceRanges(const SourceRange& body_range)
       : body_range_(body_range) {}
 
-  SourceRange GetRange(SourceRangeKind kind) {
-    DCHECK_EQ(kind, SourceRangeKind::kBody);
+  SourceRange GetRange(SourceRangeKind kind) override {
+    DCHECK(HasRange(kind));
     return body_range_;
   }
 
+  bool HasRange(SourceRangeKind kind) override {
+    return kind == SourceRangeKind::kBody;
+  }
+
  private:
   SourceRange body_range_;
 };
@@ -114,7 +133,8 @@ class ConditionalSourceRanges final : public AstNodeSourceRanges {
                                    const SourceRange& else_range)
       : then_range_(then_range), else_range_(else_range) {}
 
-  SourceRange GetRange(SourceRangeKind kind) {
+  SourceRange GetRange(SourceRangeKind kind) override {
+    DCHECK(HasRange(kind));
     switch (kind) {
       case SourceRangeKind::kThen:
         return then_range_;
@@ -125,6 +145,10 @@ class ConditionalSourceRanges final : public AstNodeSourceRanges {
     }
   }
 
+  bool HasRange(SourceRangeKind kind) override {
+    return kind == SourceRangeKind::kThen || kind == SourceRangeKind::kElse;
+  }
+
  private:
   SourceRange then_range_;
   SourceRange else_range_;
@@ -136,13 +160,15 @@ class IfStatementSourceRanges final : public AstNodeSourceRanges {
                                    const SourceRange& else_range)
       : then_range_(then_range), else_range_(else_range) {}
 
-  SourceRange GetRange(SourceRangeKind kind) {
+  SourceRange GetRange(SourceRangeKind kind) override {
+    DCHECK(HasRange(kind));
     switch (kind) {
       case SourceRangeKind::kElse:
         return else_range_;
       case SourceRangeKind::kThen:
         return then_range_;
       case SourceRangeKind::kContinuation: {
+        if (!has_continuation_) return SourceRange::Empty();
         const SourceRange& trailing_range =
             else_range_.IsEmpty() ? then_range_ : else_range_;
         return SourceRange::ContinuationOf(trailing_range);
@@ -152,29 +178,53 @@ class IfStatementSourceRanges final : public AstNodeSourceRanges {
     }
   }
 
+  bool HasRange(SourceRangeKind kind) override {
+    return kind == SourceRangeKind::kThen || kind == SourceRangeKind::kElse ||
+           kind == SourceRangeKind::kContinuation;
+  }
+
+  void RemoveContinuationRange() override {
+    DCHECK(HasRange(SourceRangeKind::kContinuation));
+    has_continuation_ = false;
+  }
+
  private:
   SourceRange then_range_;
   SourceRange else_range_;
+  bool has_continuation_ = true;
 };
 
 class IterationStatementSourceRanges final : public AstNodeSourceRanges {
  public:
   explicit IterationStatementSourceRanges(const SourceRange& body_range)
       : body_range_(body_range) {}
 
-  SourceRange GetRange(SourceRangeKind kind) {
+  SourceRange GetRange(SourceRangeKind kind) override {
+    DCHECK(HasRange(kind));
     switch (kind) {
       case SourceRangeKind::kBody:
         return body_range_;
       case SourceRangeKind::kContinuation:
+        if (!has_continuation_) return SourceRange::Empty();
         return SourceRange::ContinuationOf(body_range_);
       default:
         UNREACHABLE();
     }
   }
 
+  bool HasRange(SourceRangeKind kind) override {
+    return kind == SourceRangeKind::kBody ||
+           kind == SourceRangeKind::kContinuation;
+  }
+
+  void RemoveContinuationRange() override {
+    DCHECK(HasRange(SourceRangeKind::kContinuation));
+    has_continuation_ = false;
+  }
+
  private:
   SourceRange body_range_;
+  bool has_continuation_ = true;
 };
 
 class JumpStatementSourceRanges final : public ContinuationSourceRanges {
@@ -198,7 +248,8 @@ class NaryOperationSourceRanges final : public AstNodeSourceRanges {
   void AddRange(const SourceRange& range) { ranges_.push_back(range); }
   size_t RangeCount() const { return ranges_.size(); }
 
-  SourceRange GetRange(SourceRangeKind kind) { UNREACHABLE(); }
+  SourceRange GetRange(SourceRangeKind kind) override { UNREACHABLE(); }
+  bool HasRange(SourceRangeKind kind) override { return false; }
 
  private:
   ZoneVector<SourceRange> ranges_;
@@ -227,39 +278,65 @@ class TryCatchStatementSourceRanges final : public AstNodeSourceRanges {
   explicit TryCatchStatementSourceRanges(const SourceRange& catch_range)
       : catch_range_(catch_range) {}
 
-  SourceRange GetRange(SourceRangeKind kind) {
+  SourceRange GetRange(SourceRangeKind kind) override {
+    DCHECK(HasRange(kind));
     switch (kind) {
       case SourceRangeKind::kCatch:
         return catch_range_;
       case SourceRangeKind::kContinuation:
+        if (!has_continuation_) return SourceRange::Empty();
         return SourceRange::ContinuationOf(catch_range_);
       default:
         UNREACHABLE();
     }
   }
 
+  bool HasRange(SourceRangeKind kind) override {
+    return kind == SourceRangeKind::kCatch ||
+           kind == SourceRangeKind::kContinuation;
+  }
+
+  void RemoveContinuationRange() override {
+    DCHECK(HasRange(SourceRangeKind::kContinuation));
+    has_continuation_ = false;
+  }
+
  private:
   SourceRange catch_range_;
+  bool has_continuation_ = true;
 };
 
 class TryFinallyStatementSourceRanges final : public AstNodeSourceRanges {
  public:
   explicit TryFinallyStatementSourceRanges(const SourceRange& finally_range)
       : finally_range_(finally_range) {}
 
-  SourceRange GetRange(SourceRangeKind kind) {
+  SourceRange GetRange(SourceRangeKind kind) override {
+    DCHECK(HasRange(kind));
     switch (kind) {
       case SourceRangeKind::kFinally:
         return finally_range_;
       case SourceRangeKind::kContinuation:
+        if (!has_continuation_) return SourceRange::Empty();
         return SourceRange::ContinuationOf(finally_range_);
       default:
         UNREACHABLE();
     }
   }
 
+  bool HasRange(SourceRangeKind kind) override {
+    return kind == SourceRangeKind::kFinally ||
+           kind == SourceRangeKind::kContinuation;
+  }
+
+  void RemoveContinuationRange() override {
+    DCHECK(HasRange(SourceRangeKind::kContinuation));
+    has_continuation_ = false;
+  }
+
  private:
   SourceRange finally_range_;
+  bool has_continuation_ = true;
 };
 
 // Maps ast node pointers to associated source ranges. The parser creates these

deps/v8/src/ast/ast-traversal-visitor.h

@@ -41,7 +41,7 @@ class AstTraversalVisitor : public AstVisitor<Subclass> {
 
   // Iteration left-to-right.
   void VisitDeclarations(Declaration::List* declarations);
-  void VisitStatements(ZoneList<Statement*>* statements);
+  void VisitStatements(ZonePtrList<Statement>* statements);
 
 // Individual nodes
 #define DECLARE_VISIT(type) void Visit##type(type* node);
@@ -112,7 +112,7 @@ void AstTraversalVisitor<Subclass>::VisitDeclarations(
 
 template <class Subclass>
 void AstTraversalVisitor<Subclass>::VisitStatements(
-    ZoneList<Statement*>* stmts) {
+    ZonePtrList<Statement>* stmts) {
   for (int i = 0; i < stmts->length(); ++i) {
     Statement* stmt = stmts->at(i);
     RECURSE(Visit(stmt));
@@ -198,14 +198,14 @@ void AstTraversalVisitor<Subclass>::VisitSwitchStatement(
   PROCESS_NODE(stmt);
   RECURSE(Visit(stmt->tag()));
 
-  ZoneList<CaseClause*>* clauses = stmt->cases();
+  ZonePtrList<CaseClause>* clauses = stmt->cases();
   for (int i = 0; i < clauses->length(); ++i) {
     CaseClause* clause = clauses->at(i);
     if (!clause->is_default()) {
       Expression* label = clause->label();
       RECURSE(Visit(label));
     }
-    ZoneList<Statement*>* stmts = clause->statements();
+    ZonePtrList<Statement>* stmts = clause->statements();
     RECURSE(VisitStatements(stmts));
   }
 }
@@ -330,7 +330,7 @@ void AstTraversalVisitor<Subclass>::VisitRegExpLiteral(RegExpLiteral* expr) {
 template <class Subclass>
 void AstTraversalVisitor<Subclass>::VisitObjectLiteral(ObjectLiteral* expr) {
   PROCESS_EXPRESSION(expr);
-  ZoneList<ObjectLiteralProperty*>* props = expr->properties();
+  ZonePtrList<ObjectLiteralProperty>* props = expr->properties();
   for (int i = 0; i < props->length(); ++i) {
     ObjectLiteralProperty* prop = props->at(i);
     RECURSE_EXPRESSION(Visit(prop->key()));
@@ -341,7 +341,7 @@ void AstTraversalVisitor<Subclass>::VisitObjectLiteral(ObjectLiteral* expr) {
 template <class Subclass>
 void AstTraversalVisitor<Subclass>::VisitArrayLiteral(ArrayLiteral* expr) {
   PROCESS_EXPRESSION(expr);
-  ZoneList<Expression*>* values = expr->values();
+  ZonePtrList<Expression>* values = expr->values();
   for (int i = 0; i < values->length(); ++i) {
     Expression* value = values->at(i);
     RECURSE_EXPRESSION(Visit(value));
@@ -404,7 +404,7 @@ template <class Subclass>
 void AstTraversalVisitor<Subclass>::VisitCall(Call* expr) {
   PROCESS_EXPRESSION(expr);
   RECURSE_EXPRESSION(Visit(expr->expression()));
-  ZoneList<Expression*>* args = expr->arguments();
+  ZonePtrList<Expression>* args = expr->arguments();
   for (int i = 0; i < args->length(); ++i) {
     Expression* arg = args->at(i);
     RECURSE_EXPRESSION(Visit(arg));
@@ -415,7 +415,7 @@ template <class Subclass>
 void AstTraversalVisitor<Subclass>::VisitCallNew(CallNew* expr) {
   PROCESS_EXPRESSION(expr);
   RECURSE_EXPRESSION(Visit(expr->expression()));
-  ZoneList<Expression*>* args = expr->arguments();
+  ZonePtrList<Expression>* args = expr->arguments();
   for (int i = 0; i < args->length(); ++i) {
     Expression* arg = args->at(i);
     RECURSE_EXPRESSION(Visit(arg));
@@ -425,7 +425,7 @@ void AstTraversalVisitor<Subclass>::VisitCallNew(CallNew* expr) {
 template <class Subclass>
 void AstTraversalVisitor<Subclass>::VisitCallRuntime(CallRuntime* expr) {
   PROCESS_EXPRESSION(expr);
-  ZoneList<Expression*>* args = expr->arguments();
+  ZonePtrList<Expression>* args = expr->arguments();
   for (int i = 0; i < args->length(); ++i) {
     Expression* arg = args->at(i);
     RECURSE_EXPRESSION(Visit(arg));
@@ -487,7 +487,7 @@ void AstTraversalVisitor<Subclass>::VisitClassLiteral(ClassLiteral* expr) {
   if (expr->instance_fields_initializer_function() != nullptr) {
     RECURSE_EXPRESSION(Visit(expr->instance_fields_initializer_function()));
   }
-  ZoneList<ClassLiteralProperty*>* props = expr->properties();
+  ZonePtrList<ClassLiteral::Property>* props = expr->properties();
   for (int i = 0; i < props->length(); ++i) {
     ClassLiteralProperty* prop = props->at(i);
     if (!prop->key()->IsLiteral()) {
@@ -501,7 +501,7 @@ template <class Subclass>
 void AstTraversalVisitor<Subclass>::VisitInitializeClassFieldsStatement(
     InitializeClassFieldsStatement* stmt) {
   PROCESS_NODE(stmt);
-  ZoneList<ClassLiteralProperty*>* props = stmt->fields();
+  ZonePtrList<ClassLiteral::Property>* props = stmt->fields();
   for (int i = 0; i < props->length(); ++i) {
     ClassLiteralProperty* prop = props->at(i);
     if (!prop->key()->IsLiteral()) {

deps/v8/src/ast/ast.cc

@@ -831,7 +831,7 @@ Call::CallType Call::GetCallType() const {
   return OTHER_CALL;
 }
 
-CaseClause::CaseClause(Expression* label, ZoneList<Statement*>* statements)
+CaseClause::CaseClause(Expression* label, ZonePtrList<Statement>* statements)
     : label_(label), statements_(statements) {}
 
 bool Literal::IsPropertyName() const {
@@ -954,7 +954,7 @@ const char* CallRuntime::debug_name() {
   case k##NodeType:             \
     return static_cast<const NodeType*>(this)->labels();
 
-ZoneList<const AstRawString*>* BreakableStatement::labels() const {
+ZonePtrList<const AstRawString>* BreakableStatement::labels() const {
   switch (node_type()) {
     BREAKABLE_NODE_LIST(RETURN_LABELS)
     ITERATION_NODE_LIST(RETURN_LABELS)