Make use of profiling information for dex2oat

If the profile file exists, the compiler driver will read it
and store the data in an internal map.  Then, when we want to work
out whether to compile a method or not, the map is consulted and if
the method shows up with a high enough percentage of use we compile it.

The profile file itself is created by installd and is writeable by the
app.  The file is in /data/dalvik-cache/profiles and is named by
the package name.

This also modifies the profiler itself to:

1. Only count runnable threads (not suspended threads) in the profile
2. Use system properties to allow tuning of the profile parameters
3. Merge profiles from multiple processes using file locking.

Bug: 12877748
Change-Id: Iab2f3a327a2860db2a80d5724277d6c626227f2b

Conflicts:
	compiler/dex/frontend.cc
	compiler/dex/mir_analysis.cc
	compiler/dex/verification_results.cc
	compiler/driver/compiler_driver.cc
	dex2oat/dex2oat.cc
	runtime/class_linker.cc
	runtime/runtime.cc
	runtime/runtime.h

1 files changed, 5 insertions, 0 deletions

diff --git a/compiler/driver/compiler_options.h b/compiler/driver/compiler_options.h
index 39738ab..0cca1e9 100644
--- a/compiler/driver/compiler_options.h
+++ b/compiler/driver/compiler_options.h
@@ -23,6 +23,7 @@ class CompilerOptions {
  public:
   enum CompilerFilter {
     kInterpretOnly,       // Compile nothing.
+    kProfiled,            // Compile based on profile.
     kSpace,               // Maximize space savings.
     kBalanced,            // Try to get the best performance return on compilation investment.
     kSpeed,               // Maximize runtime performance.
@@ -30,7 +31,11 @@ class CompilerOptions {
   };
 
   // Guide heuristics to determine whether to compile method if profile data not available.
+#if ART_SMALL_MODE
+  static const CompilerFilter kDefaultCompilerFilter = kProfiled;
+#else
   static const CompilerFilter kDefaultCompilerFilter = kSpeed;
+#endif
   static const size_t kDefaultHugeMethodThreshold = 10000;
   static const size_t kDefaultLargeMethodThreshold = 600;
   static const size_t kDefaultSmallMethodThreshold = 60;