Revert "Revert "Support for inlining virtual and interface calls.""
It now works thanks to:
- https://android-review.googlesource.com/#/c/154016/ where
the invoke type is changed.
- The new FindMethodIndexIn method in this change, that
locates the right method index relative to the caller's
dex file.
This reverts commit 6e4758615308bb525b6350c30468e33a2e1f2274.
Change-Id: Iddba11664a9241e210fec211cd2aed9f4b90d118
diff --git a/compiler/optimizing/inliner.cc b/compiler/optimizing/inliner.cc
index c3fc337..5aeaad2 100644
--- a/compiler/optimizing/inliner.cc
+++ b/compiler/optimizing/inliner.cc
@@ -27,6 +27,7 @@
#include "mirror/class_loader.h"
#include "mirror/dex_cache.h"
#include "nodes.h"
+#include "reference_type_propagation.h"
#include "register_allocator.h"
#include "ssa_phi_elimination.h"
#include "scoped_thread_state_change.h"
@@ -57,7 +58,7 @@
next_block = (i == blocks.Size() - 1) ? nullptr : blocks.Get(i + 1);
for (HInstruction* instruction = block->GetFirstInstruction(); instruction != nullptr;) {
HInstruction* next = instruction->GetNext();
- HInvokeStaticOrDirect* call = instruction->AsInvokeStaticOrDirect();
+ HInvoke* call = instruction->AsInvoke();
// As long as the call is not intrinsified, it is worth trying to inline.
if (call != nullptr && call->GetIntrinsic() == Intrinsics::kNone) {
// We use the original invoke type to ensure the resolution of the called method
@@ -83,6 +84,93 @@
}
}
+static bool IsMethodOrDeclaringClassFinal(ArtMethod* method)
+ SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+ return method->IsFinal() || method->GetDeclaringClass()->IsFinal();
+}
+
+/**
+ * Given the `resolved_method` looked up in the dex cache, try to find
+ * the actual runtime target of an interface or virtual call.
+ * Return nullptr if the runtime target cannot be proven.
+ */
+static ArtMethod* FindVirtualOrInterfaceTarget(HInvoke* invoke, ArtMethod* resolved_method)
+ SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+ if (IsMethodOrDeclaringClassFinal(resolved_method)) {
+ // No need to lookup further, the resolved method will be the target.
+ return resolved_method;
+ }
+
+ HInstruction* receiver = invoke->InputAt(0);
+ if (receiver->IsNullCheck()) {
+ // Due to multiple levels of inlining within the same pass, it might be that
+ // null check does not have the reference type of the actual receiver.
+ receiver = receiver->InputAt(0);
+ }
+ ReferenceTypeInfo info = receiver->GetReferenceTypeInfo();
+ if (info.IsTop()) {
+ // We have no information on the receiver.
+ return nullptr;
+ } else if (!info.IsExact()) {
+ // We currently only support inlining with known receivers.
+ // TODO: Remove this check, we should be able to inline final methods
+ // on unknown receivers.
+ return nullptr;
+ } else if (info.GetTypeHandle()->IsInterface()) {
+ // Statically knowing that the receiver has an interface type cannot
+ // help us find what is the target method.
+ return nullptr;
+ } else if (!resolved_method->GetDeclaringClass()->IsAssignableFrom(info.GetTypeHandle().Get())) {
+ // The method that we're trying to call is not in the receiver's class or super classes.
+ return nullptr;
+ }
+
+ ClassLinker* cl = Runtime::Current()->GetClassLinker();
+ size_t pointer_size = cl->GetImagePointerSize();
+ if (invoke->IsInvokeInterface()) {
+ resolved_method = info.GetTypeHandle()->FindVirtualMethodForInterface(
+ resolved_method, pointer_size);
+ } else {
+ DCHECK(invoke->IsInvokeVirtual());
+ resolved_method = info.GetTypeHandle()->FindVirtualMethodForVirtual(
+ resolved_method, pointer_size);
+ }
+
+ if (resolved_method == nullptr) {
+ // The information we had on the receiver was not enough to find
+ // the target method. Since we check above the exact type of the receiver,
+ // the only reason this can happen is an IncompatibleClassChangeError.
+ return nullptr;
+ } else if (resolved_method->IsAbstract()) {
+ // The information we had on the receiver was not enough to find
+ // the target method. Since we check above the exact type of the receiver,
+ // the only reason this can happen is an IncompatibleClassChangeError.
+ return nullptr;
+ } else if (IsMethodOrDeclaringClassFinal(resolved_method)) {
+ // A final method has to be the target method.
+ return resolved_method;
+ } else if (info.IsExact()) {
+ // If we found a method and the receiver's concrete type is statically
+ // known, we know for sure the target.
+ return resolved_method;
+ } else {
+ // Even if we did find a method, the receiver type was not enough to
+ // statically find the runtime target.
+ return nullptr;
+ }
+}
+
+static uint32_t FindMethodIndexIn(ArtMethod* method,
+ const DexFile& dex_file,
+ uint32_t referrer_index)
+ SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+ if (method->GetDexFile()->GetLocation().compare(dex_file.GetLocation()) == 0) {
+ return method->GetDexMethodIndex();
+ } else {
+ return method->FindDexMethodIndexInOtherDexFile(dex_file, referrer_index);
+ }
+}
+
bool HInliner::TryInline(HInvoke* invoke_instruction, uint32_t method_index) const {
ScopedObjectAccess soa(Thread::Current());
const DexFile& caller_dex_file = *caller_compilation_unit_.GetDexFile();
@@ -99,6 +187,25 @@
return false;
}
+ if (!invoke_instruction->IsInvokeStaticOrDirect()) {
+ resolved_method = FindVirtualOrInterfaceTarget(invoke_instruction, resolved_method);
+ if (resolved_method == nullptr) {
+ VLOG(compiler) << "Interface or virtual call to "
+ << PrettyMethod(method_index, caller_dex_file)
+ << " could not be statically determined";
+ return false;
+ }
+ // We have found a method, but we need to find where that method is for the caller's
+ // dex file.
+ method_index = FindMethodIndexIn(resolved_method, caller_dex_file, method_index);
+ if (method_index == DexFile::kDexNoIndex) {
+ VLOG(compiler) << "Interface or virtual call to "
+ << PrettyMethod(resolved_method)
+ << " cannot be inlined because unaccessible to caller";
+ return false;
+ }
+ }
+
bool same_dex_file = true;
const DexFile& outer_dex_file = *outer_compilation_unit_.GetDexFile();
if (resolved_method->GetDexFile()->GetLocation().compare(outer_dex_file.GetLocation()) != 0) {
@@ -247,11 +354,13 @@
// Run simple optimizations on the graph.
HDeadCodeElimination dce(callee_graph, stats_);
HConstantFolding fold(callee_graph);
+ ReferenceTypePropagation type_propagation(callee_graph, handles_);
InstructionSimplifier simplify(callee_graph, stats_);
HOptimization* optimizations[] = {
&dce,
&fold,
+ &type_propagation,
&simplify,
};
@@ -265,6 +374,7 @@
outer_compilation_unit_,
dex_compilation_unit,
compiler_driver_,
+ handles_,
stats_,
depth_ + 1);
inliner.Run();