MIPS32: Improve method invocation
Improvements include:
- CodeGeneratorMIPS::GenerateStaticOrDirectCall() supports:
- MethodLoadKind::kDirectAddressWithFixup (via literals)
- CodePtrLocation::kCallDirectWithFixup (via literals)
- MethodLoadKind::kDexCachePcRelative
- 32-bit literals to support the above (not ready for general-
purpose applications yet because RA is not saved in leaf
methods, but is clobbered on MIPS32R2 when simulating
PC-relative addressing (MIPS32R6 is OK because it has
PC-relative addressing with the lwpc instruction))
- shorter instruction sequences for recursive static/direct
calls
Tested:
- test-art-host-gtest
- test-art-target-gtest and test-art-target-run-test-optimizing on:
- MIPS32R2 QEMU
- CI20 board
- MIPS32R6 (2nd arch) QEMU
Change-Id: Id5b137ad32d5590487fd154c9a01d3b3e7e044ff
diff --git a/compiler/optimizing/dex_cache_array_fixups_mips.cc b/compiler/optimizing/dex_cache_array_fixups_mips.cc
new file mode 100644
index 0000000..0f42d9c
--- /dev/null
+++ b/compiler/optimizing/dex_cache_array_fixups_mips.cc
@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2016 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 "dex_cache_array_fixups_mips.h"
+
+#include "base/arena_containers.h"
+#include "utils/dex_cache_arrays_layout-inl.h"
+
+namespace art {
+namespace mips {
+
+/**
+ * Finds instructions that need the dex cache arrays base as an input.
+ */
+class DexCacheArrayFixupsVisitor : public HGraphVisitor {
+ public:
+ explicit DexCacheArrayFixupsVisitor(HGraph* graph)
+ : HGraphVisitor(graph),
+ dex_cache_array_bases_(std::less<const DexFile*>(),
+ // Attribute memory use to code generator.
+ graph->GetArena()->Adapter(kArenaAllocCodeGenerator)) {}
+
+ void MoveBasesIfNeeded() {
+ for (const auto& entry : dex_cache_array_bases_) {
+ // Bring the base closer to the first use (previously, it was in the
+ // entry block) and relieve some pressure on the register allocator
+ // while avoiding recalculation of the base in a loop.
+ HMipsDexCacheArraysBase* base = entry.second;
+ base->MoveBeforeFirstUserAndOutOfLoops();
+ }
+ }
+
+ private:
+ void VisitInvokeStaticOrDirect(HInvokeStaticOrDirect* invoke) OVERRIDE {
+ // If this is an invoke with PC-relative access to the dex cache methods array,
+ // we need to add the dex cache arrays base as the special input.
+ if (invoke->HasPcRelativeDexCache()) {
+ // Initialize base for target method dex file if needed.
+ MethodReference target_method = invoke->GetTargetMethod();
+ HMipsDexCacheArraysBase* base = GetOrCreateDexCacheArrayBase(*target_method.dex_file);
+ // Update the element offset in base.
+ DexCacheArraysLayout layout(kMipsPointerSize, target_method.dex_file);
+ base->UpdateElementOffset(layout.MethodOffset(target_method.dex_method_index));
+ // Add the special argument base to the method.
+ DCHECK(!invoke->HasCurrentMethodInput());
+ invoke->AddSpecialInput(base);
+ }
+ }
+
+ HMipsDexCacheArraysBase* GetOrCreateDexCacheArrayBase(const DexFile& dex_file) {
+ return dex_cache_array_bases_.GetOrCreate(
+ &dex_file,
+ [this, &dex_file]() {
+ HMipsDexCacheArraysBase* base =
+ new (GetGraph()->GetArena()) HMipsDexCacheArraysBase(dex_file);
+ HBasicBlock* entry_block = GetGraph()->GetEntryBlock();
+ // Insert the base at the start of the entry block, move it to a better
+ // position later in MoveBaseIfNeeded().
+ entry_block->InsertInstructionBefore(base, entry_block->GetFirstInstruction());
+ return base;
+ });
+ }
+
+ using DexCacheArraysBaseMap =
+ ArenaSafeMap<const DexFile*, HMipsDexCacheArraysBase*, std::less<const DexFile*>>;
+ DexCacheArraysBaseMap dex_cache_array_bases_;
+};
+
+void DexCacheArrayFixups::Run() {
+ if (graph_->HasIrreducibleLoops()) {
+ // Do not run this optimization, as irreducible loops do not work with an instruction
+ // that can be live-in at the irreducible loop header.
+ return;
+ }
+ DexCacheArrayFixupsVisitor visitor(graph_);
+ visitor.VisitInsertionOrder();
+ visitor.MoveBasesIfNeeded();
+}
+
+} // namespace mips
+} // namespace art