src/v8/src/snapshot/embedded/embedded-file-writer.cc - cobalt - Git at Google

 // Copyright 2018 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "src/snapshot/embedded/embedded-file-writer.h"

 #include <cinttypes>

 #include "src/codegen/source-position-table.h"
 #include "src/objects/code-inl.h"

 namespace v8 {
 namespace internal {

 void EmbeddedFileWriter::WriteBuiltin(PlatformEmbeddedFileWriterBase* w,
                                       const i::EmbeddedData* blob,
                                       const int builtin_id) const {
   const bool is_default_variant =
       std::strcmp(embedded_variant_, kDefaultEmbeddedVariant) == 0;

   i::EmbeddedVector<char, kTemporaryStringLength> builtin_symbol;
   if (is_default_variant) {
     // Create nicer symbol names for the default mode.
     i::SNPrintF(builtin_symbol, "Builtins_%s", i::Builtins::name(builtin_id));
   } else {
     i::SNPrintF(builtin_symbol, "%s_Builtins_%s", embedded_variant_,
                 i::Builtins::name(builtin_id));
   }

   // Labels created here will show up in backtraces. We check in
   // Isolate::SetEmbeddedBlob that the blob layout remains unchanged, i.e.
   // that labels do not insert bytes into the middle of the blob byte
   // stream.
   w->DeclareFunctionBegin(builtin_symbol.begin());
   const std::vector<byte>& current_positions = source_positions_[builtin_id];

   // The code below interleaves bytes of assembly code for the builtin
   // function with source positions at the appropriate offsets.
   Vector<const byte> vpos(current_positions.data(), current_positions.size());
   v8::internal::SourcePositionTableIterator positions(
       vpos, SourcePositionTableIterator::kExternalOnly);

   const uint8_t* data = reinterpret_cast<const uint8_t*>(
       blob->InstructionStartOfBuiltin(builtin_id));
   uint32_t size = blob->PaddedInstructionSizeOfBuiltin(builtin_id);
   uint32_t i = 0;
   uint32_t next_offset =
       static_cast<uint32_t>(positions.done() ? size : positions.code_offset());
   while (i < size) {
     if (i == next_offset) {
       // Write source directive.
       w->SourceInfo(positions.source_position().ExternalFileId(),
                     GetExternallyCompiledFilename(
                         positions.source_position().ExternalFileId()),
                     positions.source_position().ExternalLine());
       positions.Advance();
       next_offset = static_cast<uint32_t>(
           positions.done() ? size : positions.code_offset());
     }
     CHECK_GE(next_offset, i);
     WriteBinaryContentsAsInlineAssembly(w, data + i, next_offset - i);
     i = next_offset;
   }

   w->DeclareFunctionEnd(builtin_symbol.begin());
 }

 void EmbeddedFileWriter::WriteFileEpilogue(PlatformEmbeddedFileWriterBase* w,
                                            const i::EmbeddedData* blob) const {
   {
     i::EmbeddedVector<char, kTemporaryStringLength> embedded_blob_code_symbol;
     i::SNPrintF(embedded_blob_code_symbol, "v8_%s_embedded_blob_code_",
                 embedded_variant_);

     w->Comment("Pointer to the beginning of the embedded blob code.");
     w->SectionData();
     w->AlignToDataAlignment();
     w->DeclarePointerToSymbol(embedded_blob_code_symbol.begin(),
                               EmbeddedBlobCodeDataSymbol().c_str());
     w->Newline();

     i::EmbeddedVector<char, kTemporaryStringLength>
         embedded_blob_metadata_symbol;
     i::SNPrintF(embedded_blob_metadata_symbol, "v8_%s_embedded_blob_metadata_",
                 embedded_variant_);

     w->Comment("Pointer to the beginning of the embedded blob metadata.");
     w->AlignToDataAlignment();
     w->DeclarePointerToSymbol(embedded_blob_metadata_symbol.begin(),
                               EmbeddedBlobMetadataDataSymbol().c_str());
     w->Newline();
   }

   {
     i::EmbeddedVector<char, kTemporaryStringLength>
         embedded_blob_code_size_symbol;
     i::SNPrintF(embedded_blob_code_size_symbol,
                 "v8_%s_embedded_blob_code_size_", embedded_variant_);

     w->Comment("The size of the embedded blob code in bytes.");
     w->SectionRoData();
     w->AlignToDataAlignment();
     w->DeclareUint32(embedded_blob_code_size_symbol.begin(), blob->code_size());
     w->Newline();

     i::EmbeddedVector<char, kTemporaryStringLength>
         embedded_blob_metadata_size_symbol;
     i::SNPrintF(embedded_blob_metadata_size_symbol,
                 "v8_%s_embedded_blob_metadata_size_", embedded_variant_);

     w->Comment("The size of the embedded blob metadata in bytes.");
     w->DeclareUint32(embedded_blob_metadata_size_symbol.begin(),
                      blob->metadata_size());
     w->Newline();
   }

 #if defined(V8_OS_WIN_X64)
   {
     i::EmbeddedVector<char, kTemporaryStringLength> unwind_info_symbol;
     i::SNPrintF(unwind_info_symbol, "%s_Builtins_UnwindInfo",
                 embedded_variant_);

     w->MaybeEmitUnwindData(unwind_info_symbol.begin(),
                            EmbeddedBlobCodeDataSymbol().c_str(), blob,
                            reinterpret_cast<const void*>(&unwind_infos_[0]));
   }
 #endif

   w->FileEpilogue();
 }

 namespace {

 int WriteDirectiveOrSeparator(PlatformEmbeddedFileWriterBase* w,
                               int current_line_length,
                               DataDirective directive) {
   int printed_chars;
   if (current_line_length == 0) {
     printed_chars = w->IndentedDataDirective(directive);
     DCHECK_LT(0, printed_chars);
   } else {
     printed_chars = fprintf(w->fp(), ",");
     DCHECK_EQ(1, printed_chars);
   }
   return current_line_length + printed_chars;
 }

 int WriteLineEndIfNeeded(PlatformEmbeddedFileWriterBase* w,
                          int current_line_length, int write_size) {
   static const int kTextWidth = 100;
   // Check if adding ',0xFF...FF\n"' would force a line wrap. This doesn't use
   // the actual size of the string to be written to determine this so it's
   // more conservative than strictly needed.
   if (current_line_length + strlen(",0x") + write_size * 2 > kTextWidth) {
     fprintf(w->fp(), "\n");
     return 0;
   } else {
     return current_line_length;
   }
 }

 }  // namespace

 // static
 void EmbeddedFileWriter::WriteBinaryContentsAsInlineAssembly(
     PlatformEmbeddedFileWriterBase* w, const uint8_t* data, uint32_t size) {
   int current_line_length = 0;
   uint32_t i = 0;

   // Begin by writing out byte chunks.
   const DataDirective directive = w->ByteChunkDataDirective();
   const int byte_chunk_size = DataDirectiveSize(directive);
   for (; i + byte_chunk_size < size; i += byte_chunk_size) {
     current_line_length =
         WriteDirectiveOrSeparator(w, current_line_length, directive);
     current_line_length += w->WriteByteChunk(data + i);
     current_line_length =
         WriteLineEndIfNeeded(w, current_line_length, byte_chunk_size);
   }
   if (current_line_length != 0) w->Newline();
   current_line_length = 0;

   // Write any trailing bytes one-by-one.
   for (; i < size; i++) {
     current_line_length =
         WriteDirectiveOrSeparator(w, current_line_length, kByte);
     current_line_length += w->HexLiteral(data[i]);
     current_line_length = WriteLineEndIfNeeded(w, current_line_length, 1);
   }

   if (current_line_length != 0) w->Newline();
 }

 int EmbeddedFileWriter::LookupOrAddExternallyCompiledFilename(
     const char* filename) {
   auto result = external_filenames_.find(filename);
   if (result != external_filenames_.end()) {
     return result->second;
   }
   int new_id =
       ExternalFilenameIndexToId(static_cast<int>(external_filenames_.size()));
   external_filenames_.insert(std::make_pair(filename, new_id));
   external_filenames_by_index_.push_back(filename);
   DCHECK_EQ(external_filenames_by_index_.size(), external_filenames_.size());
   return new_id;
 }

 const char* EmbeddedFileWriter::GetExternallyCompiledFilename(
     int fileid) const {
   size_t index = static_cast<size_t>(ExternalFilenameIdToIndex(fileid));
   DCHECK_GE(index, 0);
   DCHECK_LT(index, external_filenames_by_index_.size());

   return external_filenames_by_index_[index];
 }

 int EmbeddedFileWriter::GetExternallyCompiledFilenameCount() const {
   return static_cast<int>(external_filenames_.size());
 }

 void EmbeddedFileWriter::PrepareBuiltinSourcePositionMap(Builtins* builtins) {
   for (int i = 0; i < Builtins::builtin_count; i++) {
     // Retrieve the SourcePositionTable and copy it.
     Code code = builtins->builtin(i);
     // Verify that the code object is still the "real code" and not a
     // trampoline (which wouldn't have source positions).
     DCHECK(!code.is_off_heap_trampoline());
     std::vector<unsigned char> data(
         code.SourcePositionTable().GetDataStartAddress(),
         code.SourcePositionTable().GetDataEndAddress());
     source_positions_[i] = data;
   }
 }

 }  // namespace internal
 }  // namespace v8
	// Copyright 2018 the V8 project authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "src/snapshot/embedded/embedded-file-writer.h"

	#include <cinttypes>

	#include "src/codegen/source-position-table.h"
	#include "src/objects/code-inl.h"

	namespace v8 {
	namespace internal {

	void EmbeddedFileWriter::WriteBuiltin(PlatformEmbeddedFileWriterBase* w,
	const i::EmbeddedData* blob,
	const int builtin_id) const {
	const bool is_default_variant =
	std::strcmp(embedded_variant_, kDefaultEmbeddedVariant) == 0;

	i::EmbeddedVector<char, kTemporaryStringLength> builtin_symbol;
	if (is_default_variant) {
	// Create nicer symbol names for the default mode.
	i::SNPrintF(builtin_symbol, "Builtins_%s", i::Builtins::name(builtin_id));
	} else {
	i::SNPrintF(builtin_symbol, "%s_Builtins_%s", embedded_variant_,
	i::Builtins::name(builtin_id));
	}

	// Labels created here will show up in backtraces. We check in
	// Isolate::SetEmbeddedBlob that the blob layout remains unchanged, i.e.
	// that labels do not insert bytes into the middle of the blob byte
	// stream.
	w->DeclareFunctionBegin(builtin_symbol.begin());
	const std::vector<byte>& current_positions = source_positions_[builtin_id];

	// The code below interleaves bytes of assembly code for the builtin
	// function with source positions at the appropriate offsets.
	Vector<const byte> vpos(current_positions.data(), current_positions.size());
	v8::internal::SourcePositionTableIterator positions(
	vpos, SourcePositionTableIterator::kExternalOnly);

	const uint8_t* data = reinterpret_cast<const uint8_t*>(
	blob->InstructionStartOfBuiltin(builtin_id));
	uint32_t size = blob->PaddedInstructionSizeOfBuiltin(builtin_id);
	uint32_t i = 0;
	uint32_t next_offset =
	static_cast<uint32_t>(positions.done() ? size : positions.code_offset());
	while (i < size) {
	if (i == next_offset) {
	// Write source directive.
	w->SourceInfo(positions.source_position().ExternalFileId(),
	GetExternallyCompiledFilename(
	positions.source_position().ExternalFileId()),
	positions.source_position().ExternalLine());
	positions.Advance();
	next_offset = static_cast<uint32_t>(
	positions.done() ? size : positions.code_offset());
	}
	CHECK_GE(next_offset, i);
	WriteBinaryContentsAsInlineAssembly(w, data + i, next_offset - i);
	i = next_offset;
	}

	w->DeclareFunctionEnd(builtin_symbol.begin());
	}

	void EmbeddedFileWriter::WriteFileEpilogue(PlatformEmbeddedFileWriterBase* w,
	const i::EmbeddedData* blob) const {
	{
	i::EmbeddedVector<char, kTemporaryStringLength> embedded_blob_code_symbol;
	i::SNPrintF(embedded_blob_code_symbol, "v8_%s_embedded_blob_code_",
	embedded_variant_);

	w->Comment("Pointer to the beginning of the embedded blob code.");
	w->SectionData();
	w->AlignToDataAlignment();
	w->DeclarePointerToSymbol(embedded_blob_code_symbol.begin(),
	EmbeddedBlobCodeDataSymbol().c_str());
	w->Newline();

	i::EmbeddedVector<char, kTemporaryStringLength>
	embedded_blob_metadata_symbol;
	i::SNPrintF(embedded_blob_metadata_symbol, "v8_%s_embedded_blob_metadata_",
	embedded_variant_);

	w->Comment("Pointer to the beginning of the embedded blob metadata.");
	w->AlignToDataAlignment();
	w->DeclarePointerToSymbol(embedded_blob_metadata_symbol.begin(),
	EmbeddedBlobMetadataDataSymbol().c_str());
	w->Newline();
	}

	{
	i::EmbeddedVector<char, kTemporaryStringLength>
	embedded_blob_code_size_symbol;
	i::SNPrintF(embedded_blob_code_size_symbol,
	"v8_%s_embedded_blob_code_size_", embedded_variant_);

	w->Comment("The size of the embedded blob code in bytes.");
	w->SectionRoData();
	w->AlignToDataAlignment();
	w->DeclareUint32(embedded_blob_code_size_symbol.begin(), blob->code_size());
	w->Newline();

	i::EmbeddedVector<char, kTemporaryStringLength>
	embedded_blob_metadata_size_symbol;
	i::SNPrintF(embedded_blob_metadata_size_symbol,
	"v8_%s_embedded_blob_metadata_size_", embedded_variant_);

	w->Comment("The size of the embedded blob metadata in bytes.");
	w->DeclareUint32(embedded_blob_metadata_size_symbol.begin(),
	blob->metadata_size());
	w->Newline();
	}

	#if defined(V8_OS_WIN_X64)
	{
	i::EmbeddedVector<char, kTemporaryStringLength> unwind_info_symbol;
	i::SNPrintF(unwind_info_symbol, "%s_Builtins_UnwindInfo",
	embedded_variant_);

	w->MaybeEmitUnwindData(unwind_info_symbol.begin(),
	EmbeddedBlobCodeDataSymbol().c_str(), blob,
	reinterpret_cast<const void*>(&unwind_infos_[0]));
	}
	#endif

	w->FileEpilogue();
	}

	namespace {

	int WriteDirectiveOrSeparator(PlatformEmbeddedFileWriterBase* w,
	int current_line_length,
	DataDirective directive) {
	int printed_chars;
	if (current_line_length == 0) {
	printed_chars = w->IndentedDataDirective(directive);
	DCHECK_LT(0, printed_chars);
	} else {
	printed_chars = fprintf(w->fp(), ",");
	DCHECK_EQ(1, printed_chars);
	}
	return current_line_length + printed_chars;
	}

	int WriteLineEndIfNeeded(PlatformEmbeddedFileWriterBase* w,
	int current_line_length, int write_size) {
	static const int kTextWidth = 100;
	// Check if adding ',0xFF...FF\n"' would force a line wrap. This doesn't use
	// the actual size of the string to be written to determine this so it's
	// more conservative than strictly needed.
	if (current_line_length + strlen(",0x") + write_size * 2 > kTextWidth) {
	fprintf(w->fp(), "\n");
	return 0;
	} else {
	return current_line_length;
	}
	}

	} // namespace

	// static
	void EmbeddedFileWriter::WriteBinaryContentsAsInlineAssembly(
	PlatformEmbeddedFileWriterBase* w, const uint8_t* data, uint32_t size) {
	int current_line_length = 0;
	uint32_t i = 0;

	// Begin by writing out byte chunks.
	const DataDirective directive = w->ByteChunkDataDirective();
	const int byte_chunk_size = DataDirectiveSize(directive);
	for (; i + byte_chunk_size < size; i += byte_chunk_size) {
	current_line_length =
	WriteDirectiveOrSeparator(w, current_line_length, directive);
	current_line_length += w->WriteByteChunk(data + i);
	current_line_length =
	WriteLineEndIfNeeded(w, current_line_length, byte_chunk_size);
	}
	if (current_line_length != 0) w->Newline();
	current_line_length = 0;

	// Write any trailing bytes one-by-one.
	for (; i < size; i++) {
	current_line_length =
	WriteDirectiveOrSeparator(w, current_line_length, kByte);
	current_line_length += w->HexLiteral(data[i]);
	current_line_length = WriteLineEndIfNeeded(w, current_line_length, 1);
	}

	if (current_line_length != 0) w->Newline();
	}

	int EmbeddedFileWriter::LookupOrAddExternallyCompiledFilename(
	const char* filename) {
	auto result = external_filenames_.find(filename);
	if (result != external_filenames_.end()) {
	return result->second;
	}
	int new_id =
	ExternalFilenameIndexToId(static_cast<int>(external_filenames_.size()));
	external_filenames_.insert(std::make_pair(filename, new_id));
	external_filenames_by_index_.push_back(filename);
	DCHECK_EQ(external_filenames_by_index_.size(), external_filenames_.size());
	return new_id;
	}

	const char* EmbeddedFileWriter::GetExternallyCompiledFilename(
	int fileid) const {
	size_t index = static_cast<size_t>(ExternalFilenameIdToIndex(fileid));
	DCHECK_GE(index, 0);
	DCHECK_LT(index, external_filenames_by_index_.size());

	return external_filenames_by_index_[index];
	}

	int EmbeddedFileWriter::GetExternallyCompiledFilenameCount() const {
	return static_cast<int>(external_filenames_.size());
	}

	void EmbeddedFileWriter::PrepareBuiltinSourcePositionMap(Builtins* builtins) {
	for (int i = 0; i < Builtins::builtin_count; i++) {
	// Retrieve the SourcePositionTable and copy it.
	Code code = builtins->builtin(i);
	// Verify that the code object is still the "real code" and not a
	// trampoline (which wouldn't have source positions).
	DCHECK(!code.is_off_heap_trampoline());
	std::vector<unsigned char> data(
	code.SourcePositionTable().GetDataStartAddress(),
	code.SourcePositionTable().GetDataEndAddress());
	source_positions_[i] = data;
	}
	}

	} // namespace internal
	} // namespace v8