Merge "Don't unquicken RETURN_VOID_NO_BARRIER with vdex."

4 files changed, 33 insertions, 15 deletions

diff --git a/compiler/dex/dex_to_dex_decompiler.cc b/compiler/dex/dex_to_dex_decompiler.cc
index 051125eeaa..bfd485d126 100644
--- a/compiler/dex/dex_to_dex_decompiler.cc
+++ b/compiler/dex/dex_to_dex_decompiler.cc
@@ -27,10 +27,13 @@ namespace optimizer {
 
 class DexDecompiler {
  public:
-  DexDecompiler(const DexFile::CodeItem& code_item, const ArrayRef<const uint8_t>& quickened_info)
+  DexDecompiler(const DexFile::CodeItem& code_item,
+                const ArrayRef<const uint8_t>& quickened_info,
+                bool decompile_return_instruction)
     : code_item_(code_item),
       quickened_info_ptr_(quickened_info.data()),
-      quickened_info_end_(quickened_info.data() + quickened_info.size()) {}
+      quickened_info_end_(quickened_info.data() + quickened_info.size()),
+      decompile_return_instruction_(decompile_return_instruction) {}
 
   bool Decompile();
 
@@ -87,6 +90,7 @@ class DexDecompiler {
   const DexFile::CodeItem& code_item_;
   const uint8_t* quickened_info_ptr_;
   const uint8_t* const quickened_info_end_;
+  const bool decompile_return_instruction_;
 
   DISALLOW_COPY_AND_ASSIGN(DexDecompiler);
 };
@@ -102,7 +106,9 @@ bool DexDecompiler::Decompile() {
 
     switch (inst->Opcode()) {
       case Instruction::RETURN_VOID_NO_BARRIER:
-        inst->SetOpcode(Instruction::RETURN_VOID);
+        if (decompile_return_instruction_) {
+          inst->SetOpcode(Instruction::RETURN_VOID);
+        }
         break;
 
       case Instruction::NOP:
@@ -189,8 +195,12 @@ bool DexDecompiler::Decompile() {
 }
 
 bool ArtDecompileDEX(const DexFile::CodeItem& code_item,
-                     const ArrayRef<const uint8_t>& quickened_info) {
-  DexDecompiler decompiler(code_item, quickened_info);
+                     const ArrayRef<const uint8_t>& quickened_info,
+                     bool decompile_return_instruction) {
+  if (quickened_info.size() == 0 && !decompile_return_instruction) {
+    return true;
+  }
+  DexDecompiler decompiler(code_item, quickened_info, decompile_return_instruction);
   return decompiler.Decompile();
 }
 
diff --git a/compiler/dex/dex_to_dex_decompiler.h b/compiler/dex/dex_to_dex_decompiler.h
index 5502ca2d92..b5d5b91915 100644
--- a/compiler/dex/dex_to_dex_decompiler.h
+++ b/compiler/dex/dex_to_dex_decompiler.h
@@ -30,7 +30,8 @@ namespace optimizer {
 // consistent with DexToDexCompiler, but we should really change it to
 // DexFile::CodeItem*.
 bool ArtDecompileDEX(const DexFile::CodeItem& code_item,
-                     const ArrayRef<const uint8_t>& quickened_data);
+                     const ArrayRef<const uint8_t>& quickened_data,
+                     bool decompile_return_instruction);
 
 }  // namespace optimizer
 }  // namespace art
diff --git a/compiler/dex/dex_to_dex_decompiler_test.cc b/compiler/dex/dex_to_dex_decompiler_test.cc
index ea6c7a2e09..9a8d27cd03 100644
--- a/compiler/dex/dex_to_dex_decompiler_test.cc
+++ b/compiler/dex/dex_to_dex_decompiler_test.cc
@@ -102,7 +102,8 @@ class DexToDexDecompilerTest : public CommonCompilerTest {
         if (compiled_method != nullptr) {
           table = compiled_method->GetVmapTable();
         }
-        optimizer::ArtDecompileDEX(*it.GetMethodCodeItem(), table);
+        optimizer::ArtDecompileDEX(
+            *it.GetMethodCodeItem(), table, /* decompile_return_instruction */ true);
         it.Next();
       }
       while (it.HasNextVirtualMethod()) {
@@ -113,7 +114,8 @@ class DexToDexDecompilerTest : public CommonCompilerTest {
         if (compiled_method != nullptr) {
           table = compiled_method->GetVmapTable();
         }
-        optimizer::ArtDecompileDEX(*it.GetMethodCodeItem(), table);
+        optimizer::ArtDecompileDEX(
+            *it.GetMethodCodeItem(), table, /* decompile_return_instruction */ true);
         it.Next();
       }
       DCHECK(!it.HasNext());
diff --git a/compiler/driver/compiler_driver.cc b/compiler/driver/compiler_driver.cc
index d1a5c4d9ab..ec1642e370 100644
--- a/compiler/driver/compiler_driver.cc
+++ b/compiler/driver/compiler_driver.cc
@@ -435,7 +435,8 @@ INTRINSICS_LIST(SETUP_INTRINSICS)
 
 // In-place unquicken the given `dex_files` based on `quickening_info`.
 static void Unquicken(const std::vector<const DexFile*>& dex_files,
-                      const ArrayRef<const uint8_t>& quickening_info) {
+                      const ArrayRef<const uint8_t>& quickening_info,
+                      bool decompile_return_instruction) {
   const uint8_t* quickening_info_ptr = quickening_info.data();
   const uint8_t* const quickening_info_end = quickening_info.data() + quickening_info.size();
   for (const DexFile* dex_file : dex_files) {
@@ -454,14 +455,14 @@ static void Unquicken(const std::vector<const DexFile*>& dex_files,
         it.Next();
       }
 
-      // Unquicken each method.
       while (it.HasNextDirectMethod()) {
         const DexFile::CodeItem* code_item = it.GetMethodCodeItem();
         if (code_item != nullptr) {
           uint32_t quickening_size = *reinterpret_cast<const uint32_t*>(quickening_info_ptr);
           quickening_info_ptr += sizeof(uint32_t);
-          optimizer::ArtDecompileDEX(
-              *code_item, ArrayRef<const uint8_t>(quickening_info_ptr, quickening_size));
+          optimizer::ArtDecompileDEX(*code_item,
+                                     ArrayRef<const uint8_t>(quickening_info_ptr, quickening_size),
+                                     decompile_return_instruction);
           quickening_info_ptr += quickening_size;
         }
         it.Next();
@@ -472,8 +473,9 @@ static void Unquicken(const std::vector<const DexFile*>& dex_files,
         if (code_item != nullptr) {
           uint32_t quickening_size = *reinterpret_cast<const uint32_t*>(quickening_info_ptr);
           quickening_info_ptr += sizeof(uint32_t);
-          optimizer::ArtDecompileDEX(
-              *code_item, ArrayRef<const uint8_t>(quickening_info_ptr, quickening_size));
+          optimizer::ArtDecompileDEX(*code_item,
+                                     ArrayRef<const uint8_t>(quickening_info_ptr, quickening_size),
+                                     decompile_return_instruction);
           quickening_info_ptr += quickening_size;
         }
         it.Next();
@@ -493,7 +495,10 @@ void CompilerDriver::CompileAll(jobject class_loader,
     // if the boot image has changed. How exactly we'll know is under
     // experimentation.
     TimingLogger::ScopedTiming t("Unquicken", timings);
-    Unquicken(dex_files, vdex_file->GetQuickeningInfo());
+    // We do not decompile a RETURN_VOID_NO_BARRIER into a RETURN_VOID, as the quickening
+    // optimization does not depend on the boot image (the optimization relies on not
+    // having final fields in a class, which does not change for an app).
+    Unquicken(dex_files, vdex_file->GetQuickeningInfo(), /* decompile_return_instruction */ false);
     Runtime::Current()->GetCompilerCallbacks()->SetVerifierDeps(
         new verifier::VerifierDeps(dex_files, vdex_file->GetVerifierDepsData()));
   }