Load ArtMethod* from .data.bimg.rel.ro entries.
Introduce a new .data.bimg.rel.ro section in oat files where
we store offsets of boot image objects from the beginning of
the boot image. At runtime we relocate these entries using
the actual boot image address to turn offsets to pointers.
Use the .data.bimg.rel.ro to prepare the boot image methods
used by HInvokeStaticOrDirect for PIC AOT app compilation.
Loading the ArtMethod* from .data.bimg.rel.ro instead of the
.bss avoids the initial call to the resolution trampoline.
Test: Additional test in 522-checker-sharpening
Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing --pictest --npictest
Test: Pixel 2 XL boots.
Test: testrunner.py --target --optimizing --pictest --npictest
Bug: 71526895
Change-Id: Ie5f5b1f622704877b36730377146e59092e46c0c
diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index 0c20556..2e625a7 100644
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -3360,9 +3360,10 @@
CHECK_EQ(dex_cache_location, dex_file_suffix);
const OatFile* oat_file =
(dex_file.GetOatDexFile() != nullptr) ? dex_file.GetOatDexFile()->GetOatFile() : nullptr;
- // Clean up pass to remove null dex caches. Also check if we need to initialize OatFile .bss.
- // Null dex caches can occur due to class unloading and we are lazily removing null entries.
- bool initialize_oat_file_bss = (oat_file != nullptr);
+ // Clean up pass to remove null dex caches; null dex caches can occur due to class unloading
+ // and we are lazily removing null entries. Also check if we need to initialize OatFile data
+ // (.data.bimg.rel.ro and .bss sections) needed for code execution.
+ bool initialize_oat_file_data = (oat_file != nullptr) && oat_file->IsExecutable();
JavaVMExt* const vm = self->GetJniEnv()->GetVm();
for (auto it = dex_caches_.begin(); it != dex_caches_.end(); ) {
DexCacheData data = *it;
@@ -3370,15 +3371,36 @@
vm->DeleteWeakGlobalRef(self, data.weak_root);
it = dex_caches_.erase(it);
} else {
- if (initialize_oat_file_bss &&
+ if (initialize_oat_file_data &&
it->dex_file->GetOatDexFile() != nullptr &&
it->dex_file->GetOatDexFile()->GetOatFile() == oat_file) {
- initialize_oat_file_bss = false; // Already initialized.
+ initialize_oat_file_data = false; // Already initialized.
}
++it;
}
}
- if (initialize_oat_file_bss) {
+ if (initialize_oat_file_data) {
+ // Initialize the .data.bimg.rel.ro section.
+ if (!oat_file->GetBootImageRelocations().empty()) {
+ uint8_t* reloc_begin = const_cast<uint8_t*>(oat_file->DataBimgRelRoBegin());
+ CheckedCall(mprotect,
+ "un-protect boot image relocations",
+ reloc_begin,
+ oat_file->DataBimgRelRoSize(),
+ PROT_READ | PROT_WRITE);
+ uint32_t boot_image_begin = dchecked_integral_cast<uint32_t>(reinterpret_cast<uintptr_t>(
+ Runtime::Current()->GetHeap()->GetBootImageSpaces().front()->Begin()));
+ for (const uint32_t& relocation : oat_file->GetBootImageRelocations()) {
+ const_cast<uint32_t&>(relocation) += boot_image_begin;
+ }
+ CheckedCall(mprotect,
+ "protect boot image relocations",
+ reloc_begin,
+ oat_file->DataBimgRelRoSize(),
+ PROT_READ);
+ }
+
+ // Initialize the .bss section.
// TODO: Pre-initialize from boot/app image?
ArtMethod* resolution_method = Runtime::Current()->GetResolutionMethod();
for (ArtMethod*& entry : oat_file->GetBssMethods()) {