deps: backport 010897c from V8 upstream

This is a reland of https://github.com/nodejs/node/pull/3165. The patch abates
the truncation of script filenames in the perf-event output produced by V8.

V8 commits:
Original: https://github.com/v8/v8/commit/03ef3cd004c2fd31ae7e48772f106df67b8c2feb
Reland: https://github.com/v8/v8/commit/010897c16adb46d3fe403eab525502a63e174b0c

Original commit message:
  improve perf_basic_prof filename reporting

  The buffer used for appending filenames to the string printed to the
  perf_basic_prof log was unnecessarily too small. Bump it up to be at least
  kUtf8BufferSize.

  Truncation of filenames makes it really hard to work with profiles gathered on
  Node.js. Because of the way Node.js works, you can have node module dependencies
  in deeply nested directories. The last thing you want when investigating a
  performance problem is to have script names be truncated.

  This patch is a stop-gap. Ideally, I want no truncation of the filename at all
  and use a dynamically growing buffer. That would be a larger change, and I
  wanted to have a quick fix available that can be back-ported to Node.js LTS
  release.

  R=yangguo@chromium.org,yurys@chromium.org
  BUG=

  Review URL: https://codereview.chromium.org/1388543002

PR-URL: https://github.com/nodejs/node/pull/3520
Reviewed-By: bnoordhuis - Ben Noordhuis <info@bnoordhuis.nl>

2 files changed, 62 insertions, 5 deletions

diff --git a/deps/v8/src/log.cc b/deps/v8/src/log.cc
index 044250f119..84c863b654 100644
--- a/deps/v8/src/log.cc
+++ b/deps/v8/src/log.cc
@@ -125,8 +125,9 @@ class CodeEventLogger::NameBuffer {
   }
 
   void AppendInt(int n) {
-    Vector<char> buffer(utf8_buffer_ + utf8_pos_,
-                        kUtf8BufferSize - utf8_pos_);
+    int space = kUtf8BufferSize - utf8_pos_;
+    if (space <= 0) return;
+    Vector<char> buffer(utf8_buffer_ + utf8_pos_, space);
     int size = SNPrintF(buffer, "%d", n);
     if (size > 0 && utf8_pos_ + size <= kUtf8BufferSize) {
       utf8_pos_ += size;
@@ -134,8 +135,9 @@ class CodeEventLogger::NameBuffer {
   }
 
   void AppendHex(uint32_t n) {
-    Vector<char> buffer(utf8_buffer_ + utf8_pos_,
-                        kUtf8BufferSize - utf8_pos_);
+    int space = kUtf8BufferSize - utf8_pos_;
+    if (space <= 0) return;
+    Vector<char> buffer(utf8_buffer_ + utf8_pos_, space);
     int size = SNPrintF(buffer, "%x", n);
     if (size > 0 && utf8_pos_ + size <= kUtf8BufferSize) {
       utf8_pos_ += size;
@@ -147,7 +149,7 @@ class CodeEventLogger::NameBuffer {
 
  private:
   static const int kUtf8BufferSize = 512;
-  static const int kUtf16BufferSize = 128;
+  static const int kUtf16BufferSize = kUtf8BufferSize;
 
   int utf8_pos_;
   char utf8_buffer_[kUtf8BufferSize];
diff --git a/deps/v8/test/cctest/test-log.cc b/deps/v8/test/cctest/test-log.cc
index 0938a9ede2..daf2e688b6 100644
--- a/deps/v8/test/cctest/test-log.cc
+++ b/deps/v8/test/cctest/test-log.cc
@@ -531,3 +531,58 @@ TEST(LogVersion) {
   }
   isolate->Dispose();
 }
+
+
+// https://crbug.com/539892
+// CodeCreateEvents with really large names should not crash.
+TEST(Issue539892) {
+  class : public i::CodeEventLogger {
+   public:
+    virtual void CodeMoveEvent(Address from, Address to) {}
+    virtual void CodeDeleteEvent(Address from) {}
+    virtual void CodeDisableOptEvent(i::Code* code,
+                                     i::SharedFunctionInfo* shared) {}
+
+   private:
+    virtual void LogRecordedBuffer(i::Code* code, i::SharedFunctionInfo* shared,
+                                   const char* name, int length) {}
+  } code_event_logger;
+  SETUP_FLAGS();
+  v8::Isolate::CreateParams create_params;
+  create_params.array_buffer_allocator = CcTest::array_buffer_allocator();
+  v8::Isolate* isolate = v8::Isolate::New(create_params);
+
+  {
+    ScopedLoggerInitializer initialize_logger(saved_log, saved_prof, isolate);
+    Logger* logger = initialize_logger.logger();
+    logger->addCodeEventListener(&code_event_logger);
+
+    // Function with a really large name.
+    const char* source_text =
+        "(function "
+        "baaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+        "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaac"
+        "(){})();";
+
+    CompileRun(source_text);
+
+    // Must not crash.
+    logger->LogCompiledFunctions();
+  }
+  isolate->Dispose();
+}