deps: v8, cherry-pick 9365d09, aac2f8c, 47d34a3

    Original commit message 9365d09:

        [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 aac2f8c:

        [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

    deps: V8: backport 47d34a3

    Original commit message:

        Revert "[coverage] change block range to avoid ambiguity."

        This reverts commit 471fef0469d04d7c487f3a08e81f3d77566a2f50.

        Reason for revert: A more general fix incoming at https://crrev.com/c/1273095.

        Original change's description:
        > [coverage] change block range to avoid ambiguity.
        >
        > By moving the block range end to left of closing bracket,
        > we can avoid ambiguity where an open-ended singleton range
        > could be both interpreted as inside the parent range, or
        > next to it.
        >
        > R=<U+200B>verwaest@chromium.org
        >
        > Bug: v8:8237
        > Change-Id: Ibc9412b31efe900b6d8bff0d8fa8c52ddfbf460a
        > Reviewed-on: https://chromium-review.googlesource.com/1254127
        > Reviewed-by: Georg Neis <neis@chromium.org>
        > Commit-Queue: Yang Guo <yangguo@chromium.org>
        > Cr-Commit-Position: refs/heads/master@{#56347}

        TBR=yangguo@chromium.org,neis@chromium.org,verwaest@chromium.org

        # Not skipping CQ checks because original CL landed > 1 day ago.

        Bug: v8:8237
        Change-Id: I39310cf3c2f06a0d98ff314740aaeefbfffc0834
        Reviewed-on: https://chromium-review.googlesource.com/c/1273096
        Reviewed-by: Jakob Gruber <jgruber@chromium.org>
        Reviewed-by: Toon Verwaest <verwaest@chromium.org>
        Reviewed-by: Yang Guo <yangguo@chromium.org>
        Commit-Queue: Jakob Gruber <jgruber@chromium.org>
        Cr-Commit-Position: refs/heads/master@{#56513}

    Refs: https://github.com/v8/v8/commit/47d34a317e47bad86b68326607cd2e6de3901f3e

PR-URL: https://github.com/nodejs/node/pull/25429
Reviewed-By: Yang Guo <yangguo@chromium.org>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/deps/v8/src/parsing/parser.cc b/deps/v8/src/parsing/parser.cc
index 6d0d9fff21..5687633f2f 100644
--- a/deps/v8/src/parsing/parser.cc
+++ b/deps/v8/src/parsing/parser.cc
@@ -10,6 +10,7 @@
 #include "src/ast/ast-function-literal-id-reindexer.h"
 #include "src/ast/ast-traversal-visitor.h"
 #include "src/ast/ast.h"
+#include "src/ast/source-range-ast-visitor.h"
 #include "src/bailout-reason.h"
 #include "src/base/platform/platform.h"
 #include "src/char-predicates-inl.h"
@@ -441,6 +442,15 @@ void MaybeResetCharacterStream(ParseInfo* info, FunctionLiteral* literal) {
   }
 }
 
+void MaybeProcessSourceRanges(ParseInfo* parse_info, Expression* root,
+                              uintptr_t stack_limit_) {
+  if (root != nullptr && parse_info->source_range_map() != nullptr) {
+    SourceRangeAstVisitor visitor(stack_limit_, root,
+                                  parse_info->source_range_map());
+    visitor.Run();
+  }
+}
+
 }  // namespace
 
 FunctionLiteral* Parser::ParseProgram(Isolate* isolate, ParseInfo* info) {
@@ -464,6 +474,7 @@ FunctionLiteral* Parser::ParseProgram(Isolate* isolate, ParseInfo* info) {
   scanner_.Initialize();
   FunctionLiteral* result = DoParseProgram(isolate, info);
   MaybeResetCharacterStream(info, result);
+  MaybeProcessSourceRanges(info, result, stack_limit_);
 
   HandleSourceURLComments(isolate, info->script());
 
@@ -660,6 +671,7 @@ FunctionLiteral* Parser::ParseFunction(Isolate* isolate, ParseInfo* info,
   FunctionLiteral* result =
       DoParseFunction(isolate, info, info->function_name());
   MaybeResetCharacterStream(info, result);
+  MaybeProcessSourceRanges(info, result, stack_limit_);
   if (result != nullptr) {
     Handle<String> inferred_name(shared_info->inferred_name(), isolate);
     result->set_inferred_name(inferred_name);