| // Copyright 2011 the V8 project authors. All rights reserved. |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following |
| // disclaimer in the documentation and/or other materials provided |
| // with the distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived |
| // from this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| #include "../include/v8-preparser.h" |
| |
| #include "globals.h" |
| #include "checks.h" |
| #include "allocation.h" |
| #include "utils.h" |
| #include "list.h" |
| #include "scanner-base.h" |
| #include "preparse-data-format.h" |
| #include "preparse-data.h" |
| #include "preparser.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| // UTF16Buffer based on a v8::UnicodeInputStream. |
| class InputStreamUTF16Buffer : public UC16CharacterStream { |
| public: |
| /* The InputStreamUTF16Buffer maintains an internal buffer |
| * that is filled in chunks from the UC16CharacterStream. |
| * It also maintains unlimited pushback capability, but optimized |
| * for small pushbacks. |
| * The pushback_buffer_ pointer points to the limit of pushbacks |
| * in the current buffer. There is room for a few pushback'ed chars before |
| * the buffer containing the most recently read chunk. If this is overflowed, |
| * an external buffer is allocated/reused to hold further pushbacks, and |
| * pushback_buffer_ and buffer_cursor_/buffer_end_ now points to the |
| * new buffer. When this buffer is read to the end again, the cursor is |
| * switched back to the internal buffer |
| */ |
| explicit InputStreamUTF16Buffer(v8::UnicodeInputStream* stream) |
| : UC16CharacterStream(), |
| stream_(stream), |
| pushback_buffer_(buffer_), |
| pushback_buffer_end_cache_(NULL), |
| pushback_buffer_backing_(NULL), |
| pushback_buffer_backing_size_(0) { |
| buffer_cursor_ = buffer_end_ = buffer_ + kPushBackSize; |
| } |
| |
| virtual ~InputStreamUTF16Buffer() { |
| if (pushback_buffer_backing_ != NULL) { |
| DeleteArray(pushback_buffer_backing_); |
| } |
| } |
| |
| virtual void PushBack(uc32 ch) { |
| ASSERT(pos_ > 0); |
| if (ch == kEndOfInput) { |
| pos_--; |
| return; |
| } |
| if (buffer_cursor_ <= pushback_buffer_) { |
| // No more room in the current buffer to do pushbacks. |
| if (pushback_buffer_end_cache_ == NULL) { |
| // We have overflowed the pushback space at the beginning of buffer_. |
| // Switch to using a separate allocated pushback buffer. |
| if (pushback_buffer_backing_ == NULL) { |
| // Allocate a buffer the first time we need it. |
| pushback_buffer_backing_ = NewArray<uc16>(kPushBackSize); |
| pushback_buffer_backing_size_ = kPushBackSize; |
| } |
| pushback_buffer_ = pushback_buffer_backing_; |
| pushback_buffer_end_cache_ = buffer_end_; |
| buffer_end_ = pushback_buffer_backing_ + pushback_buffer_backing_size_; |
| buffer_cursor_ = buffer_end_ - 1; |
| } else { |
| // Hit the bottom of the allocated pushback buffer. |
| // Double the buffer and continue. |
| uc16* new_buffer = NewArray<uc16>(pushback_buffer_backing_size_ * 2); |
| memcpy(new_buffer + pushback_buffer_backing_size_, |
| pushback_buffer_backing_, |
| pushback_buffer_backing_size_); |
| DeleteArray(pushback_buffer_backing_); |
| buffer_cursor_ = new_buffer + pushback_buffer_backing_size_; |
| pushback_buffer_backing_ = pushback_buffer_ = new_buffer; |
| buffer_end_ = pushback_buffer_backing_ + pushback_buffer_backing_size_; |
| } |
| } |
| pushback_buffer_[buffer_cursor_ - pushback_buffer_- 1] = |
| static_cast<uc16>(ch); |
| pos_--; |
| } |
| |
| protected: |
| virtual bool ReadBlock() { |
| if (pushback_buffer_end_cache_ != NULL) { |
| buffer_cursor_ = buffer_; |
| buffer_end_ = pushback_buffer_end_cache_; |
| pushback_buffer_end_cache_ = NULL; |
| return buffer_end_ > buffer_cursor_; |
| } |
| // Copy the top of the buffer into the pushback area. |
| int32_t value; |
| uc16* buffer_start = buffer_ + kPushBackSize; |
| buffer_cursor_ = buffer_end_ = buffer_start; |
| while ((value = stream_->Next()) >= 0) { |
| if (value > static_cast<int32_t>(unibrow::Utf8::kMaxThreeByteChar)) { |
| value = unibrow::Utf8::kBadChar; |
| } |
| // buffer_end_ is a const pointer, but buffer_ is writable. |
| buffer_start[buffer_end_++ - buffer_start] = static_cast<uc16>(value); |
| if (buffer_end_ == buffer_ + kPushBackSize + kBufferSize) break; |
| } |
| return buffer_end_ > buffer_start; |
| } |
| |
| virtual unsigned SlowSeekForward(unsigned pos) { |
| // Seeking in the input is not used by preparsing. |
| // It's only used by the real parser based on preparser data. |
| UNIMPLEMENTED(); |
| return 0; |
| } |
| |
| private: |
| static const unsigned kBufferSize = 512; |
| static const unsigned kPushBackSize = 16; |
| v8::UnicodeInputStream* const stream_; |
| // Buffer holding first kPushBackSize characters of pushback buffer, |
| // then kBufferSize chars of read-ahead. |
| // The pushback buffer is only used if pushing back characters past |
| // the start of a block. |
| uc16 buffer_[kPushBackSize + kBufferSize]; |
| // Limit of pushbacks before new allocation is necessary. |
| uc16* pushback_buffer_; |
| // Only if that pushback buffer at the start of buffer_ isn't sufficient |
| // is the following used. |
| const uc16* pushback_buffer_end_cache_; |
| uc16* pushback_buffer_backing_; |
| unsigned pushback_buffer_backing_size_; |
| }; |
| |
| |
| class StandAloneJavaScriptScanner : public JavaScriptScanner { |
| public: |
| explicit StandAloneJavaScriptScanner(UnicodeCache* unicode_cache) |
| : JavaScriptScanner(unicode_cache) { } |
| |
| void Initialize(UC16CharacterStream* source) { |
| source_ = source; |
| Init(); |
| // Skip initial whitespace allowing HTML comment ends just like |
| // after a newline and scan first token. |
| has_line_terminator_before_next_ = true; |
| has_multiline_comment_before_next_ = false; |
| SkipWhiteSpace(); |
| Scan(); |
| } |
| }; |
| |
| |
| // Functions declared by allocation.h and implemented in both api.cc (for v8) |
| // or here (for a stand-alone preparser). |
| |
| void FatalProcessOutOfMemory(const char* reason) { |
| V8_Fatal(__FILE__, __LINE__, reason); |
| } |
| |
| bool EnableSlowAsserts() { return true; } |
| |
| } // namespace internal. |
| |
| |
| UnicodeInputStream::~UnicodeInputStream() { } |
| |
| |
| PreParserData Preparse(UnicodeInputStream* input, size_t max_stack) { |
| internal::InputStreamUTF16Buffer buffer(input); |
| uintptr_t stack_limit = reinterpret_cast<uintptr_t>(&buffer) - max_stack; |
| internal::UnicodeCache unicode_cache; |
| internal::StandAloneJavaScriptScanner scanner(&unicode_cache); |
| scanner.Initialize(&buffer); |
| internal::CompleteParserRecorder recorder; |
| preparser::PreParser::PreParseResult result = |
| preparser::PreParser::PreParseProgram(&scanner, |
| &recorder, |
| true, |
| stack_limit); |
| if (result == preparser::PreParser::kPreParseStackOverflow) { |
| return PreParserData::StackOverflow(); |
| } |
| internal::Vector<unsigned> pre_data = recorder.ExtractData(); |
| size_t size = pre_data.length() * sizeof(pre_data[0]); |
| unsigned char* data = reinterpret_cast<unsigned char*>(pre_data.start()); |
| return PreParserData(size, data); |
| } |
| |
| } // namespace v8. |
| |
| |
| // Used by ASSERT macros and other immediate exits. |
| extern "C" void V8_Fatal(const char* file, int line, const char* format, ...) { |
| exit(EXIT_FAILURE); |
| } |