Significantly improve performance of code coverage tool by precomputing a map token_pos->line numbe…

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 7909 matching lines @@
 void Script::set_kind(RawScript::Kind value) const {
   raw_ptr()->kind_ = value;
 }
 
 
 void Script::set_tokens(const TokenStream& value) const {
   StorePointer(&raw_ptr()->tokens_, value.raw());
 }
 
 
+void Script::set_token_pos_to_line_nr(const TypedData& value) const {
+  StorePointer(&raw_ptr()->token_pos_to_line_nr_, value.raw());
+}
+
+
+RawTypedData* Script::token_pos_to_line_nr() const {
+  return raw_ptr()->token_pos_to_line_nr_;
+}
+
+
 void Script::Tokenize(const String& private_key) const {
   Isolate* isolate = Isolate::Current();
   const TokenStream& tkns = TokenStream::Handle(isolate, tokens());
   if (!tkns.IsNull()) {
     // Already tokenized.
     return;
   }
   // Get the source, scan and allocate the token stream.
   VMTagScope tagScope(isolate, VMTag::kCompileScannerTagId);
   TimerScope timer(FLAG_compiler_stats, &CompilerStats::scanner_timer);
@@ skipping 14 matching lines @@
   ASSERT(col_offset >= 0);
   raw_ptr()->line_offset_ = line_offset;
   raw_ptr()->col_offset_ = col_offset;
 }
 
 
 void Script::GetTokenLocation(intptr_t token_pos,
                               intptr_t* line,
                               intptr_t* column) const {
   ASSERT(line != NULL);
-  const TokenStream& tkns = TokenStream::Handle(tokens());
   if (column == NULL) {
+    if (token_pos_to_line_nr() != TypedData::null()) {
+      const TypedData& array = TypedData::Handle(token_pos_to_line_nr());
+      *line = array.GetInt32(token_pos * array.ElementSizeInBytes());
+      return;
+    }
+    const TokenStream& tkns = TokenStream::Handle(tokens());
     TokenStream::Iterator tkit(tkns, 0, TokenStream::Iterator::kAllTokens);
     intptr_t cur_line = line_offset() + 1;
     while (tkit.CurrentPosition() < token_pos &&
            tkit.CurrentTokenKind() != Token::kEOS) {
       if (tkit.CurrentTokenKind() == Token::kNEWLINE) {
         cur_line++;
       }
       tkit.Advance();
     }
     *line = cur_line;
   } else {
+    const TokenStream& tkns = TokenStream::Handle(tokens());
     const String& src = String::Handle(Source());
     intptr_t src_pos = tkns.ComputeSourcePosition(token_pos);
     Scanner scanner(src, Symbols::Empty());
     scanner.ScanTo(src_pos);
     intptr_t relative_line = scanner.CurrentPosition().line;
     *line = relative_line + line_offset();
     *column = scanner.CurrentPosition().column;
     // On the first line of the script we must add the column offset.
     if (relative_line == 1) {
       *column += col_offset();
     }
   }
 }
 
 
+void Script::ComputeTokenPosToLineNumberArray() const {
+  if (token_pos_to_line_nr() != TypedData::null()) {
+    // Already computed.
+    return;
+  }
+
+  const TokenStream& tkns = TokenStream::Handle(tokens());
+  const intptr_t len = ExternalTypedData::Handle(tkns.GetStream()).Length();
+  const TypedData& array =
+      TypedData::Handle(TypedData::New(kTypedDataInt32ArrayCid, len));
+  const intptr_t elem_size_in_bytes = array.ElementSizeInBytes();
+  set_token_pos_to_line_nr(array);
+  TokenStream::Iterator tkit(tkns, 0, TokenStream::Iterator::kAllTokens);
+  intptr_t array_offset_in_bytes = 0;
+  intptr_t cur_line = line_offset() + 1;
+  while (tkit.CurrentTokenKind() != Token::kEOS) {
+    array.SetInt32(tkit.CurrentPosition() * elem_size_in_bytes, cur_line);
+    array_offset_in_bytes += elem_size_in_bytes;
+    if (tkit.CurrentTokenKind() == Token::kNEWLINE) {
+      cur_line++;
+    }
+    tkit.Advance();
+  }
+}
+
+
 void Script::TokenRangeAtLine(intptr_t line_number,
                               intptr_t* first_token_index,
                               intptr_t* last_token_index) const {
   ASSERT(first_token_index != NULL && last_token_index != NULL);
   ASSERT(line_number > 0);
   *first_token_index = -1;
   *last_token_index = -1;
   const TokenStream& tkns = TokenStream::Handle(tokens());
   line_number -= line_offset();
   if (line_number < 1) line_number = 1;
@@ skipping 10254 matching lines @@
   16,  // kTypedDataFloat64x2ArrayCid,
 };
 
 
 RawTypedData* TypedData::New(intptr_t class_id,
                              intptr_t len,
                              Heap::Space space) {
   if (len < 0 || len > TypedData::MaxElements(class_id)) {
     FATAL1("Fatal error in TypedData::New: invalid len %" Pd "\n", len);
   }
+  ASSERT(RawObject::IsTypedDataClassId(class_id));
   TypedData& result = TypedData::Handle();
   {
     intptr_t lengthInBytes = len * ElementSizeInBytes(class_id);
     RawObject* raw = Object::Allocate(class_id,
                                       TypedData::InstanceSize(lengthInBytes),
                                       space);
     NoGCScope no_gc;
     result ^= raw;
     result.SetLength(len);
     if (len > 0) {
@@ skipping 731 matching lines @@
   return tag_label.ToCString();
 }
 
 
 void UserTag::PrintJSONImpl(JSONStream* stream, bool ref) const {
   Instance::PrintJSONImpl(stream, ref);
 }
 
 
 }  // namespace dart