Remove gaps between images
We now use the same logic to calculate the size as we use to create
the image header. This should mean that it always lines up correctly.
Previously the alignment rounding could have caused page off by one
errors in some cases.
Re-enable no gap check in heap.cc.
Bug: 26317072
Change-Id: I558a4e60197ca4613fc4ec4c3a618c64a83d006a
diff --git a/compiler/image_writer.cc b/compiler/image_writer.cc
index 503b75b..2985ca9 100644
--- a/compiler/image_writer.cc
+++ b/compiler/image_writer.cc
@@ -635,11 +635,11 @@
bool ImageWriter::AllocMemory() {
for (const char* oat_filename : oat_filenames_) {
ImageInfo& image_info = GetImageInfo(oat_filename);
- const size_t length = RoundUp(image_objects_offset_begin_ +
- GetBinSizeSum(image_info) +
- image_info.intern_table_bytes_ +
- class_table_bytes_,
- kPageSize);
+ ImageSection unused_sections[ImageHeader::kSectionCount];
+ const size_t length = RoundUp(
+ image_info.CreateImageSections(target_ptr_size_, unused_sections),
+ kPageSize);
+
std::string error_msg;
image_info.image_.reset(MemMap::MapAnonymous("image writer image",
nullptr,
@@ -1287,18 +1287,11 @@
ImageInfo& image_info = GetImageInfo(oat_filename);
image_info.image_begin_ = global_image_begin_ + image_offset;
image_info.image_offset_ = image_offset;
- size_t native_sections_size = image_info.bin_slot_sizes_[kBinArtField] +
- image_info.bin_slot_sizes_[kBinArtMethodDirty] +
- image_info.bin_slot_sizes_[kBinArtMethodClean] +
- image_info.bin_slot_sizes_[kBinDexCacheArray] +
- image_info.intern_table_bytes_ +
- class_table_bytes_;
- size_t image_objects = RoundUp(image_info.image_end_, kPageSize);
- size_t bitmap_size =
- RoundUp(gc::accounting::ContinuousSpaceBitmap::ComputeBitmapSize(image_objects), kPageSize);
- size_t heap_size = gc::accounting::ContinuousSpaceBitmap::ComputeHeapSize(bitmap_size);
- size_t max = std::max(heap_size, image_info.image_end_ + native_sections_size + bitmap_size);
- image_info.image_size_ = RoundUp(max, kPageSize);
+ ImageSection unused_sections[ImageHeader::kSectionCount];
+ image_info.image_size_ = RoundUp(
+ image_info.CreateImageSections(target_ptr_size_, unused_sections),
+ kPageSize);
+ // There should be no gaps until the next image.
image_offset += image_info.image_size_;
}
@@ -1346,6 +1339,49 @@
// Note that image_info.image_end_ is left at end of used mirror object section.
}
+size_t ImageWriter::ImageInfo::CreateImageSections(size_t target_ptr_size,
+ ImageSection* out_sections) const {
+ DCHECK(out_sections != nullptr);
+ // Objects section
+ auto* objects_section = &out_sections[ImageHeader::kSectionObjects];
+ *objects_section = ImageSection(0u, image_end_);
+ size_t cur_pos = objects_section->End();
+ // Add field section.
+ auto* field_section = &out_sections[ImageHeader::kSectionArtFields];
+ *field_section = ImageSection(cur_pos, bin_slot_sizes_[kBinArtField]);
+ CHECK_EQ(bin_slot_offsets_[kBinArtField], field_section->Offset());
+ cur_pos = field_section->End();
+ // Round up to the alignment the required by the method section.
+ cur_pos = RoundUp(cur_pos, ArtMethod::Alignment(target_ptr_size));
+ // Add method section.
+ auto* methods_section = &out_sections[ImageHeader::kSectionArtMethods];
+ *methods_section = ImageSection(cur_pos,
+ bin_slot_sizes_[kBinArtMethodClean] +
+ bin_slot_sizes_[kBinArtMethodDirty]);
+ CHECK_EQ(bin_slot_offsets_[kBinArtMethodClean], methods_section->Offset());
+ cur_pos = methods_section->End();
+ // Add dex cache arrays section.
+ auto* dex_cache_arrays_section = &out_sections[ImageHeader::kSectionDexCacheArrays];
+ *dex_cache_arrays_section = ImageSection(cur_pos, bin_slot_sizes_[kBinDexCacheArray]);
+ CHECK_EQ(bin_slot_offsets_[kBinDexCacheArray], dex_cache_arrays_section->Offset());
+ cur_pos = dex_cache_arrays_section->End();
+ // Round up to the alignment the string table expects. See HashSet::WriteToMemory.
+ cur_pos = RoundUp(cur_pos, sizeof(uint64_t));
+ // Calculate the size of the interned strings.
+ auto* interned_strings_section = &out_sections[ImageHeader::kSectionInternedStrings];
+ *interned_strings_section = ImageSection(cur_pos, intern_table_bytes_);
+ cur_pos = interned_strings_section->End();
+ // Round up to the alignment the class table expects. See HashSet::WriteToMemory.
+ cur_pos = RoundUp(cur_pos, sizeof(uint64_t));
+ // Calculate the size of the class table section.
+ auto* class_table_section = &out_sections[ImageHeader::kSectionClassTable];
+ // TODO: class_table_bytes_
+ *class_table_section = ImageSection(cur_pos, 0u);
+ cur_pos = class_table_section->End();
+ // Image end goes right before the start of the image bitmap.
+ return cur_pos;
+}
+
void ImageWriter::CreateHeader(size_t oat_loaded_size, size_t oat_data_offset) {
CHECK_NE(0U, oat_loaded_size);
const char* oat_filename = oat_file_->GetLocation().c_str();
@@ -1358,48 +1394,12 @@
// Create the image sections.
ImageSection sections[ImageHeader::kSectionCount];
- // Objects section
- auto* objects_section = §ions[ImageHeader::kSectionObjects];
- *objects_section = ImageSection(0u, image_info.image_end_);
- size_t cur_pos = objects_section->End();
- // Add field section.
- auto* field_section = §ions[ImageHeader::kSectionArtFields];
- *field_section = ImageSection(cur_pos, image_info.bin_slot_sizes_[kBinArtField]);
- CHECK_EQ(image_info.bin_slot_offsets_[kBinArtField], field_section->Offset());
- cur_pos = field_section->End();
- // Round up to the alignment the required by the method section.
- cur_pos = RoundUp(cur_pos, ArtMethod::Alignment(target_ptr_size_));
- // Add method section.
- auto* methods_section = §ions[ImageHeader::kSectionArtMethods];
- *methods_section = ImageSection(cur_pos,
- image_info.bin_slot_sizes_[kBinArtMethodClean] +
- image_info.bin_slot_sizes_[kBinArtMethodDirty]);
- CHECK_EQ(image_info.bin_slot_offsets_[kBinArtMethodClean], methods_section->Offset());
- cur_pos = methods_section->End();
- // Add dex cache arrays section.
- auto* dex_cache_arrays_section = §ions[ImageHeader::kSectionDexCacheArrays];
- *dex_cache_arrays_section = ImageSection(cur_pos, image_info.bin_slot_sizes_[kBinDexCacheArray]);
- CHECK_EQ(image_info.bin_slot_offsets_[kBinDexCacheArray], dex_cache_arrays_section->Offset());
- cur_pos = dex_cache_arrays_section->End();
- // Round up to the alignment the string table expects. See HashSet::WriteToMemory.
- cur_pos = RoundUp(cur_pos, sizeof(uint64_t));
- // Calculate the size of the interned strings.
- auto* interned_strings_section = §ions[ImageHeader::kSectionInternedStrings];
- *interned_strings_section = ImageSection(cur_pos, image_info.intern_table_bytes_);
- cur_pos = interned_strings_section->End();
- // Round up to the alignment the class table expects. See HashSet::WriteToMemory.
- cur_pos = RoundUp(cur_pos, sizeof(uint64_t));
- // Calculate the size of the class table section.
- auto* class_table_section = §ions[ImageHeader::kSectionClassTable];
- *class_table_section = ImageSection(cur_pos, class_table_bytes_);
- cur_pos = class_table_section->End();
- // Image end goes right before the start of the image bitmap.
- const size_t image_end = static_cast<uint32_t>(cur_pos);
+ const size_t image_end = image_info.CreateImageSections(target_ptr_size_, sections);
+
// Finally bitmap section.
const size_t bitmap_bytes = image_info.image_bitmap_->Size();
auto* bitmap_section = §ions[ImageHeader::kSectionImageBitmap];
- *bitmap_section = ImageSection(RoundUp(cur_pos, kPageSize), RoundUp(bitmap_bytes, kPageSize));
- cur_pos = bitmap_section->End();
+ *bitmap_section = ImageSection(RoundUp(image_end, kPageSize), RoundUp(bitmap_bytes, kPageSize));
if (VLOG_IS_ON(compiler)) {
LOG(INFO) << "Creating header for " << oat_filename;
size_t idx = 0;
diff --git a/compiler/image_writer.h b/compiler/image_writer.h
index e5f7dc7..d423799 100644
--- a/compiler/image_writer.h
+++ b/compiler/image_writer.h
@@ -214,6 +214,10 @@
ImageInfo();
ImageInfo(ImageInfo&&) = default;
+ // Create the image sections into the out sections variable, returns the size of the image
+ // excluding the bitmap.
+ size_t CreateImageSections(size_t target_ptr_size, ImageSection* out_sections) const;
+
std::unique_ptr<MemMap> image_; // Memory mapped for generating the image.
// Target begin of this image. Notes: It is not valid to write here, this is the address