commit f1d666e1b48f8070ef1177fce156c08827f08eb8
author Mathieu Chartier <mathieuc@google.com> Thu Sep 03 16:13:34 2015 -0700
committer Mathieu Chartier <mathieuc@google.com> Thu Sep 03 17:33:19 2015 -0700
tree 772cbbe6652b32ea2be31532156295db27579390
parent 897ce64153e4758663e464fb5fb339f9a7b496c8

Add ScopedThreadSuspension

Fixes the TransitionFromRunnableToSuspended and
TransitionFromSuspendedToRunnable pattern that was prone to errors.

Change-Id: Ie6ae9c0357c83b4fc4899d05dfa0975553170267

compiler/image_writer.cc

diff --git a/compiler/image_writer.cc b/compiler/image_writer.cc
index dbd3366..f318921 100644
--- a/compiler/image_writer.cc
+++ b/compiler/image_writer.cc
@@ -85,11 +85,9 @@
 bool ImageWriter::PrepareImageAddressSpace() {
   target_ptr_size_ = InstructionSetPointerSize(compiler_driver_.GetInstructionSet());
   {
-    Thread::Current()->TransitionFromSuspendedToRunnable();
+    ScopedObjectAccess soa(Thread::Current());
     PruneNonImageClasses();  // Remove junk
     ComputeLazyFieldsForImageClasses();  // Add useful information
-
-    Thread::Current()->TransitionFromRunnableToSuspended(kNative);
   }
   gc::Heap* heap = Runtime::Current()->GetHeap();
   heap->CollectGarbage(false);  // Remove garbage.
@@ -109,9 +107,10 @@
     CheckNonImageClassesRemoved();
   }
 
-  Thread::Current()->TransitionFromSuspendedToRunnable();
-  CalculateNewObjectOffsets();
-  Thread::Current()->TransitionFromRunnableToSuspended(kNative);
+  {
+    ScopedObjectAccess soa(Thread::Current());
+    CalculateNewObjectOffsets();
+  }
 
   // This needs to happen after CalculateNewObjectOffsets since it relies on intern_table_bytes_ and
   // bin size sums being calculated.
@@ -164,14 +163,14 @@
   size_t oat_data_offset = 0;
   ElfWriter::GetOatElfInformation(oat_file.get(), &oat_loaded_size, &oat_data_offset);
 
-  Thread::Current()->TransitionFromSuspendedToRunnable();
-
-  CreateHeader(oat_loaded_size, oat_data_offset);
-  CopyAndFixupNativeData();
-  // TODO: heap validation can't handle these fix up passes.
-  Runtime::Current()->GetHeap()->DisableObjectValidation();
-  CopyAndFixupObjects();
-  Thread::Current()->TransitionFromRunnableToSuspended(kNative);
+  {
+    ScopedObjectAccess soa(Thread::Current());
+    CreateHeader(oat_loaded_size, oat_data_offset);
+    CopyAndFixupNativeData();
+    // TODO: heap validation can't handle these fix up passes.
+    Runtime::Current()->GetHeap()->DisableObjectValidation();
+    CopyAndFixupObjects();
+  }
 
   SetOatChecksumFromElfFile(oat_file.get());