dex2oat/linker/image_test.cc - LeafOS-Project/android_art - Gitiles

 /*
  * Copyright (C) 2011 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include <string.h>
 #include <vector>

 #include "image_test.h"

 #include "oat/image.h"
 #include "scoped_thread_state_change-inl.h"
 #include "thread.h"

 namespace art {
 namespace linker {

 TEST_F(ImageTest, TestImageLayout) {
   std::vector<size_t> image_sizes;
   std::vector<size_t> image_sizes_extra;
   // Compile multi-image with ImageLayoutA being the last image.
   {
     CompilationHelper helper;
     Compile(ImageHeader::kStorageModeUncompressed,
             /*max_image_block_size=*/std::numeric_limits<uint32_t>::max(),
             helper,
             "ImageLayoutA",
             {"LMyClass;"});
     image_sizes = helper.GetImageObjectSectionSizes();
   }
   TearDown();
   runtime_.reset();
   SetUp();
   // Compile multi-image with ImageLayoutB being the last image.
   {
     CompilationHelper helper;
     Compile(ImageHeader::kStorageModeUncompressed,
             /*max_image_block_size=*/std::numeric_limits<uint32_t>::max(),
             helper,
             "ImageLayoutB",
             {"LMyClass;"});
     image_sizes_extra = helper.GetImageObjectSectionSizes();
   }
   // Make sure that the new stuff in the clinit in ImageLayoutB is in the last image and not in the
   // first two images.
   ASSERT_EQ(image_sizes.size(), image_sizes.size());
   // Sizes of the object sections should be the same for all but the last image.
   for (size_t i = 0; i < image_sizes.size() - 1; ++i) {
     EXPECT_EQ(image_sizes[i], image_sizes_extra[i]);
   }
   // Last image should be larger since it has a hash map and a string.
   EXPECT_LT(image_sizes.back(), image_sizes_extra.back());
 }

 TEST_F(ImageTest, ImageHeaderIsValid) {
   uint32_t image_begin = ART_BASE_ADDRESS;
   uint32_t image_size_ = kElfSegmentAlignment;
   uint32_t image_roots = ART_BASE_ADDRESS + (1 * KB);
   uint32_t oat_checksum = 0;
   uint32_t oat_file_begin = ART_BASE_ADDRESS + (kElfSegmentAlignment);
   uint32_t oat_data_begin = ART_BASE_ADDRESS + (2 * kElfSegmentAlignment);
   uint32_t oat_data_end = ART_BASE_ADDRESS + (2 * kElfSegmentAlignment + 1 * KB);
   uint32_t oat_file_end = ART_BASE_ADDRESS + (2 * kElfSegmentAlignment + 2 * KB);
   ImageSection sections[ImageHeader::kSectionCount];
   uint32_t image_reservation_size = RoundUp(oat_file_end - image_begin, kElfSegmentAlignment);
   ImageHeader image_header(image_reservation_size,
                            /*component_count=*/ 1u,
                            image_begin,
                            image_size_,
                            sections,
                            image_roots,
                            oat_checksum,
                            oat_file_begin,
                            oat_data_begin,
                            oat_data_end,
                            oat_file_end,
                            /*boot_image_begin=*/ 0u,
                            /*boot_image_size=*/ 0u,
                            /*boot_image_component_count=*/ 0u,
                            /*boot_image_checksum=*/ 0u,
                            sizeof(void*));

   ASSERT_TRUE(image_header.IsValid());

   // Please note that for the following condition to be true, the above values should be chosen in
   // a way that image_reservation_size != RoundUp(image_size_, kElfSegmentAlignment).
   ASSERT_TRUE(!image_header.IsAppImage());

   char* magic = const_cast<char*>(image_header.GetMagic());
   strcpy(magic, "");  // bad magic
   ASSERT_FALSE(image_header.IsValid());
   strcpy(magic, "art\n000");  // bad version
   ASSERT_FALSE(image_header.IsValid());
 }

 // Test that pointer to quick code is the same in
 // a default method of an interface and in a copied method
 // of a class which implements the interface. This should be true
 // only if the copied method and the origin method are located in the
 // same oat file.
 TEST_F(ImageTest, TestDefaultMethods) {
   // Use this test to compile managed code to catch crashes when compiling the boot class path.
   // This test already needs to compile some managed methods and by compiling with "speed" we
   // avoid the need to create a specialized profile for the "speed-profile" compilation.
   // (Using "speed" shall compile most methods. We could compile more with "everything".)
   SetCompilerFilter(CompilerFilter::kSpeed);
   CompilationHelper helper;
   Compile(ImageHeader::kStorageModeUncompressed,
           /*max_image_block_size=*/std::numeric_limits<uint32_t>::max(),
           helper,
           "DefaultMethods",
           {"LIface;", "LImpl;", "LIterableBase;"});

   PointerSize pointer_size = class_linker_->GetImagePointerSize();
   Thread* self = Thread::Current();
   ScopedObjectAccess soa(self);

   // Test the pointer to quick code is the same in origin method
   // and in the copied method from the same oat file.
   ObjPtr<mirror::Class> iface_klass =
       class_linker_->LookupClass(self, "LIface;", /*class_loader=*/ nullptr);
   ASSERT_NE(nullptr, iface_klass);
   ArtMethod* origin = iface_klass->FindInterfaceMethod("defaultMethod", "()V", pointer_size);
   ASSERT_NE(nullptr, origin);
   ASSERT_OBJ_PTR_EQ(origin->GetDeclaringClass(), iface_klass);
   const void* code = origin->GetEntryPointFromQuickCompiledCodePtrSize(pointer_size);
   // The origin method should have a pointer to quick code
   ASSERT_NE(nullptr, code);
   ASSERT_FALSE(class_linker_->IsQuickToInterpreterBridge(code));
   ObjPtr<mirror::Class> impl_klass =
       class_linker_->LookupClass(self, "LImpl;", /*class_loader=*/ nullptr);
   ASSERT_NE(nullptr, impl_klass);
   ArtMethod* copied = FindCopiedMethod(origin, impl_klass);
   ASSERT_NE(nullptr, copied);
   // the copied method should have pointer to the same quick code as the origin method
   ASSERT_EQ(code, copied->GetEntryPointFromQuickCompiledCodePtrSize(pointer_size));

   // Test the origin method has pointer to quick code
   // but the copied method has pointer to interpreter
   // because these methods are in different oat files.
   ObjPtr<mirror::Class> iterable_klass =
       class_linker_->LookupClass(self, "Ljava/lang/Iterable;", /*class_loader=*/ nullptr);
   ASSERT_NE(nullptr, iterable_klass);
   origin = iterable_klass->FindClassMethod(
       "forEach", "(Ljava/util/function/Consumer;)V", pointer_size);
   ASSERT_NE(nullptr, origin);
   ASSERT_FALSE(origin->IsDirect());
   ASSERT_OBJ_PTR_EQ(origin->GetDeclaringClass(), iterable_klass);
   code = origin->GetEntryPointFromQuickCompiledCodePtrSize(pointer_size);
   // the origin method should have a pointer to quick code
   ASSERT_NE(nullptr, code);
   ASSERT_FALSE(class_linker_->IsQuickToInterpreterBridge(code));
   ObjPtr<mirror::Class> iterablebase_klass =
       class_linker_->LookupClass(self, "LIterableBase;", /*class_loader=*/ nullptr);
   ASSERT_NE(nullptr, iterablebase_klass);
   copied = FindCopiedMethod(origin, iterablebase_klass);
   ASSERT_NE(nullptr, copied);
   code = copied->GetEntryPointFromQuickCompiledCodePtrSize(pointer_size);
   // the copied method should have a pointer to interpreter
   ASSERT_TRUE(class_linker_->IsQuickToInterpreterBridge(code));
 }

 // Regression test for dex2oat crash for soft verification failure during
 // class initialization check from the transactional interpreter while
 // running the class initializer for another class.
 TEST_F(ImageTest, TestSoftVerificationFailureDuringClassInitialization) {
   CompilationHelper helper;
   Compile(ImageHeader::kStorageModeUncompressed,
           /*max_image_block_size=*/std::numeric_limits<uint32_t>::max(),
           helper,
           "VerifySoftFailDuringClinit",
           /*image_classes=*/ {"LClassToInitialize;"},
           /*image_classes_failing_aot_clinit=*/ {"LClassToInitialize;"});
 }

 TEST_F(ImageTest, TestImageClassWithArrayClassWithUnresolvedComponent) {
   CompilationHelper helper;
   Compile(ImageHeader::kStorageModeUncompressed,
           /*max_image_block_size=*/std::numeric_limits<uint32_t>::max(),
           helper,
           "ArrayClassWithUnresolvedComponent",
           /*image_classes=*/ {"LClassWithStatic;",
                               "LClassWithStaticConst;",
                               "[LClassWithMissingInterface;",
                               "[[LClassWithMissingInterface;",
                               "[LClassWithMissingSuper",
                               "[[LClassWithMissingSuper"},
           /*image_classes_failing_aot_clinit=*/ {
                               "LClassWithStatic;",
                               "LClassWithStaticConst;"},
           /*image_classes_failing_resolution=*/ {
                               "[LClassWithMissingInterface;",
                               "[[LClassWithMissingInterface;",
                               "[LClassWithMissingSuper",
                               "[[LClassWithMissingSuper"});
 }

 TEST_F(ImageTest, TestSuperWithAccessChecks) {
   CompilationHelper helper;
   Compile(ImageHeader::kStorageModeUncompressed,
           /*max_image_block_size=*/std::numeric_limits<uint32_t>::max(),
           helper,
           "SuperWithAccessChecks",
           /*image_classes=*/ {"LSubClass;", "LImplementsClass;"},
           /*image_classes_failing_aot_clinit=*/ {"LSubClass;", "LImplementsClass;"});
 }

 // Regression test for b/297453985, where we used to generate a bogus image
 // checksum.
 TEST_F(ImageTest, ImageChecksum) {
   uint32_t image_begin = ART_BASE_ADDRESS;
   uint32_t image_roots = ART_BASE_ADDRESS + (1 * KB);
   ImageSection sections[ImageHeader::kSectionCount];
   // We require bitmap section to be at least kElfSegmentAlignment.
   sections[ImageHeader::kSectionImageBitmap] = ImageSection(0, kElfSegmentAlignment);
   ImageHeader image_header(/*image_reservation_size=*/ kElfSegmentAlignment,
                            /*component_count=*/ 1u,
                            image_begin,
                            /*image_size=*/ sizeof(ImageHeader),
                            sections,
                            image_roots,
                            /*oat_checksum=*/ 0u,
                            /*oat_file_begin=*/ 0u,
                            /*oat_data_begin=*/ 0u,
                            /*oat_data_end=*/ 0u,
                            /*oat_file_end=*/ 0u,
                            /*boot_image_begin=*/ 0u,
                            /*boot_image_size=*/ 0u,
                            /*boot_image_component_count=*/ 0u,
                            /*boot_image_checksum=*/ 0u,
                            sizeof(void*));
     ASSERT_TRUE(image_header.IsValid());

     std::string error_msg;
     ImageFileGuard image_file;
     ScratchFile location;
     image_file.reset(OS::CreateEmptyFile(location.GetFilename().c_str()));
     const uint8_t* data = reinterpret_cast<const uint8_t*>(&image_header);
     std::unique_ptr<uint8_t> bitmap(new uint8_t[kElfSegmentAlignment]);
     memset(bitmap.get(), 0, kElfSegmentAlignment);
     ASSERT_EQ(image_header.GetImageChecksum(), 0u);
     ASSERT_TRUE(image_header.WriteData(
         image_file,
         data,
         bitmap.get(),
         ImageHeader::kStorageModeUncompressed,
         /*max_image_block_size=*/std::numeric_limits<uint32_t>::max(),
         /*update_checksum=*/ true,
         &error_msg)) << error_msg;

     uint32_t first_checksum = image_header.GetImageChecksum();
     // Reset the image checksum, `WriteData` updated it.
     image_header.SetImageChecksum(0u);

     // Change the header to ensure the checksum will be different.
     image_header.SetOatChecksum(0xFFFF);

     ASSERT_TRUE(image_header.WriteData(
         image_file,
         data,
         bitmap.get(),
         ImageHeader::kStorageModeUncompressed,
         /*max_image_block_size=*/std::numeric_limits<uint32_t>::max(),
         /*update_checksum=*/ true,
         &error_msg)) << error_msg;

     ASSERT_NE(first_checksum, image_header.GetImageChecksum());
 }

 }  // namespace linker
 }  // namespace art
	/*
	* Copyright (C) 2011 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include <string.h>
	#include <vector>

	#include "image_test.h"

	#include "oat/image.h"
	#include "scoped_thread_state_change-inl.h"
	#include "thread.h"

	namespace art {
	namespace linker {

	TEST_F(ImageTest, TestImageLayout) {
	std::vector<size_t> image_sizes;
	std::vector<size_t> image_sizes_extra;
	// Compile multi-image with ImageLayoutA being the last image.
	{
	CompilationHelper helper;
	Compile(ImageHeader::kStorageModeUncompressed,
	/max_image_block_size=/std::numeric_limits<uint32_t>::max(),
	helper,
	"ImageLayoutA",
	{"LMyClass;"});
	image_sizes = helper.GetImageObjectSectionSizes();
	}
	TearDown();
	runtime_.reset();
	SetUp();
	// Compile multi-image with ImageLayoutB being the last image.
	{
	CompilationHelper helper;
	Compile(ImageHeader::kStorageModeUncompressed,
	/max_image_block_size=/std::numeric_limits<uint32_t>::max(),
	helper,
	"ImageLayoutB",
	{"LMyClass;"});
	image_sizes_extra = helper.GetImageObjectSectionSizes();
	}
	// Make sure that the new stuff in the clinit in ImageLayoutB is in the last image and not in the
	// first two images.
	ASSERT_EQ(image_sizes.size(), image_sizes.size());
	// Sizes of the object sections should be the same for all but the last image.
	for (size_t i = 0; i < image_sizes.size() - 1; ++i) {
	EXPECT_EQ(image_sizes[i], image_sizes_extra[i]);
	}
	// Last image should be larger since it has a hash map and a string.
	EXPECT_LT(image_sizes.back(), image_sizes_extra.back());
	}

	TEST_F(ImageTest, ImageHeaderIsValid) {
	uint32_t image_begin = ART_BASE_ADDRESS;
	uint32_t image_size_ = kElfSegmentAlignment;
	uint32_t image_roots = ART_BASE_ADDRESS + (1 * KB);
	uint32_t oat_checksum = 0;
	uint32_t oat_file_begin = ART_BASE_ADDRESS + (kElfSegmentAlignment);
	uint32_t oat_data_begin = ART_BASE_ADDRESS + (2 * kElfSegmentAlignment);
	uint32_t oat_data_end = ART_BASE_ADDRESS + (2 * kElfSegmentAlignment + 1 * KB);
	uint32_t oat_file_end = ART_BASE_ADDRESS + (2 * kElfSegmentAlignment + 2 * KB);
	ImageSection sections[ImageHeader::kSectionCount];
	uint32_t image_reservation_size = RoundUp(oat_file_end - image_begin, kElfSegmentAlignment);
	ImageHeader image_header(image_reservation_size,
	/component_count=/ 1u,
	image_begin,
	image_size_,
	sections,
	image_roots,
	oat_checksum,
	oat_file_begin,
	oat_data_begin,
	oat_data_end,
	oat_file_end,
	/boot_image_begin=/ 0u,
	/boot_image_size=/ 0u,
	/boot_image_component_count=/ 0u,
	/boot_image_checksum=/ 0u,
	sizeof(void*));

	ASSERT_TRUE(image_header.IsValid());

	// Please note that for the following condition to be true, the above values should be chosen in
	// a way that image_reservation_size != RoundUp(image_size_, kElfSegmentAlignment).
	ASSERT_TRUE(!image_header.IsAppImage());

	char* magic = const_cast<char*>(image_header.GetMagic());
	strcpy(magic, ""); // bad magic
	ASSERT_FALSE(image_header.IsValid());
	strcpy(magic, "art\n000"); // bad version
	ASSERT_FALSE(image_header.IsValid());
	}

	// Test that pointer to quick code is the same in
	// a default method of an interface and in a copied method
	// of a class which implements the interface. This should be true
	// only if the copied method and the origin method are located in the
	// same oat file.
	TEST_F(ImageTest, TestDefaultMethods) {
	// Use this test to compile managed code to catch crashes when compiling the boot class path.
	// This test already needs to compile some managed methods and by compiling with "speed" we
	// avoid the need to create a specialized profile for the "speed-profile" compilation.
	// (Using "speed" shall compile most methods. We could compile more with "everything".)
	SetCompilerFilter(CompilerFilter::kSpeed);
	CompilationHelper helper;
	Compile(ImageHeader::kStorageModeUncompressed,
	/max_image_block_size=/std::numeric_limits<uint32_t>::max(),
	helper,
	"DefaultMethods",
	{"LIface;", "LImpl;", "LIterableBase;"});

	PointerSize pointer_size = class_linker_->GetImagePointerSize();
	Thread* self = Thread::Current();
	ScopedObjectAccess soa(self);

	// Test the pointer to quick code is the same in origin method
	// and in the copied method from the same oat file.
	ObjPtr<mirror::Class> iface_klass =
	class_linker_->LookupClass(self, "LIface;", /class_loader=/ nullptr);
	ASSERT_NE(nullptr, iface_klass);
	ArtMethod* origin = iface_klass->FindInterfaceMethod("defaultMethod", "()V", pointer_size);
	ASSERT_NE(nullptr, origin);
	ASSERT_OBJ_PTR_EQ(origin->GetDeclaringClass(), iface_klass);
	const void* code = origin->GetEntryPointFromQuickCompiledCodePtrSize(pointer_size);
	// The origin method should have a pointer to quick code
	ASSERT_NE(nullptr, code);
	ASSERT_FALSE(class_linker_->IsQuickToInterpreterBridge(code));
	ObjPtr<mirror::Class> impl_klass =
	class_linker_->LookupClass(self, "LImpl;", /class_loader=/ nullptr);
	ASSERT_NE(nullptr, impl_klass);
	ArtMethod* copied = FindCopiedMethod(origin, impl_klass);
	ASSERT_NE(nullptr, copied);
	// the copied method should have pointer to the same quick code as the origin method
	ASSERT_EQ(code, copied->GetEntryPointFromQuickCompiledCodePtrSize(pointer_size));

	// Test the origin method has pointer to quick code
	// but the copied method has pointer to interpreter
	// because these methods are in different oat files.
	ObjPtr<mirror::Class> iterable_klass =
	class_linker_->LookupClass(self, "Ljava/lang/Iterable;", /class_loader=/ nullptr);
	ASSERT_NE(nullptr, iterable_klass);
	origin = iterable_klass->FindClassMethod(
	"forEach", "(Ljava/util/function/Consumer;)V", pointer_size);
	ASSERT_NE(nullptr, origin);
	ASSERT_FALSE(origin->IsDirect());
	ASSERT_OBJ_PTR_EQ(origin->GetDeclaringClass(), iterable_klass);
	code = origin->GetEntryPointFromQuickCompiledCodePtrSize(pointer_size);
	// the origin method should have a pointer to quick code
	ASSERT_NE(nullptr, code);
	ASSERT_FALSE(class_linker_->IsQuickToInterpreterBridge(code));
	ObjPtr<mirror::Class> iterablebase_klass =
	class_linker_->LookupClass(self, "LIterableBase;", /class_loader=/ nullptr);
	ASSERT_NE(nullptr, iterablebase_klass);
	copied = FindCopiedMethod(origin, iterablebase_klass);
	ASSERT_NE(nullptr, copied);
	code = copied->GetEntryPointFromQuickCompiledCodePtrSize(pointer_size);
	// the copied method should have a pointer to interpreter
	ASSERT_TRUE(class_linker_->IsQuickToInterpreterBridge(code));
	}

	// Regression test for dex2oat crash for soft verification failure during
	// class initialization check from the transactional interpreter while
	// running the class initializer for another class.
	TEST_F(ImageTest, TestSoftVerificationFailureDuringClassInitialization) {
	CompilationHelper helper;
	Compile(ImageHeader::kStorageModeUncompressed,
	/max_image_block_size=/std::numeric_limits<uint32_t>::max(),
	helper,
	"VerifySoftFailDuringClinit",
	/image_classes=/ {"LClassToInitialize;"},
	/image_classes_failing_aot_clinit=/ {"LClassToInitialize;"});
	}

	TEST_F(ImageTest, TestImageClassWithArrayClassWithUnresolvedComponent) {
	CompilationHelper helper;
	Compile(ImageHeader::kStorageModeUncompressed,
	/max_image_block_size=/std::numeric_limits<uint32_t>::max(),
	helper,
	"ArrayClassWithUnresolvedComponent",
	/image_classes=/ {"LClassWithStatic;",
	"LClassWithStaticConst;",
	"[LClassWithMissingInterface;",
	"[[LClassWithMissingInterface;",
	"[LClassWithMissingSuper",
	"[[LClassWithMissingSuper"},
	/image_classes_failing_aot_clinit=/ {
	"LClassWithStatic;",
	"LClassWithStaticConst;"},
	/image_classes_failing_resolution=/ {
	"[LClassWithMissingInterface;",
	"[[LClassWithMissingInterface;",
	"[LClassWithMissingSuper",
	"[[LClassWithMissingSuper"});
	}

	TEST_F(ImageTest, TestSuperWithAccessChecks) {
	CompilationHelper helper;
	Compile(ImageHeader::kStorageModeUncompressed,
	/max_image_block_size=/std::numeric_limits<uint32_t>::max(),
	helper,
	"SuperWithAccessChecks",
	/image_classes=/ {"LSubClass;", "LImplementsClass;"},
	/image_classes_failing_aot_clinit=/ {"LSubClass;", "LImplementsClass;"});
	}

	// Regression test for b/297453985, where we used to generate a bogus image
	// checksum.
	TEST_F(ImageTest, ImageChecksum) {
	uint32_t image_begin = ART_BASE_ADDRESS;
	uint32_t image_roots = ART_BASE_ADDRESS + (1 * KB);
	ImageSection sections[ImageHeader::kSectionCount];
	// We require bitmap section to be at least kElfSegmentAlignment.
	sections[ImageHeader::kSectionImageBitmap] = ImageSection(0, kElfSegmentAlignment);
	ImageHeader image_header(/image_reservation_size=/ kElfSegmentAlignment,
	/component_count=/ 1u,
	image_begin,
	/image_size=/ sizeof(ImageHeader),
	sections,
	image_roots,
	/oat_checksum=/ 0u,
	/oat_file_begin=/ 0u,
	/oat_data_begin=/ 0u,
	/oat_data_end=/ 0u,
	/oat_file_end=/ 0u,
	/boot_image_begin=/ 0u,
	/boot_image_size=/ 0u,
	/boot_image_component_count=/ 0u,
	/boot_image_checksum=/ 0u,
	sizeof(void*));
	ASSERT_TRUE(image_header.IsValid());

	std::string error_msg;
	ImageFileGuard image_file;
	ScratchFile location;
	image_file.reset(OS::CreateEmptyFile(location.GetFilename().c_str()));
	const uint8_t* data = reinterpret_cast<const uint8_t*>(&image_header);
	std::unique_ptr<uint8_t> bitmap(new uint8_t[kElfSegmentAlignment]);
	memset(bitmap.get(), 0, kElfSegmentAlignment);
	ASSERT_EQ(image_header.GetImageChecksum(), 0u);
	ASSERT_TRUE(image_header.WriteData(
	image_file,
	data,
	bitmap.get(),
	ImageHeader::kStorageModeUncompressed,
	/max_image_block_size=/std::numeric_limits<uint32_t>::max(),
	/update_checksum=/ true,
	&error_msg)) << error_msg;

	uint32_t first_checksum = image_header.GetImageChecksum();
	// Reset the image checksum, `WriteData` updated it.
	image_header.SetImageChecksum(0u);

	// Change the header to ensure the checksum will be different.
	image_header.SetOatChecksum(0xFFFF);

	ASSERT_TRUE(image_header.WriteData(
	image_file,
	data,
	bitmap.get(),
	ImageHeader::kStorageModeUncompressed,
	/max_image_block_size=/std::numeric_limits<uint32_t>::max(),
	/update_checksum=/ true,
	&error_msg)) << error_msg;

	ASSERT_NE(first_checksum, image_header.GetImageChecksum());
	}

	} // namespace linker
	} // namespace art