Reduce interpret-only compile time.

Before:
39.04user 5.18system 0:29.24elapsed 151%CPU (0avgtext+0avgdata 164176maxresident)k
38.87user 5.16system 0:29.14elapsed 151%CPU (0avgtext+0avgdata 164144maxresident)k

After:
36.26user 3.25system 0:27.00elapsed 146%CPU (0avgtext+0avgdata 162592maxresident)k
36.25user 3.28system 0:26.28elapsed 150%CPU (0avgtext+0avgdata 162688maxresident)k

Disabled implicit stack protection for the compiler, this reduces page faults.

Added support for not timing every method compilation and verification. NanoTime is
slow and adds ~2 seconds of real time. This is currently enabled since people want
to know which methods are slow to compile.

Bug: 16853450

Change-Id: I349ffb3f36db8c437137387aa6914dc17d743f09

1 files changed, 9 insertions, 5 deletions

diff --git a/compiler/driver/compiler_driver.cc b/compiler/driver/compiler_driver.cc
index d1458bcf08..ec3955b1f5 100644
--- a/compiler/driver/compiler_driver.cc
+++ b/compiler/driver/compiler_driver.cc
@@ -61,6 +61,8 @@
 
 namespace art {
 
+static constexpr bool kTimeCompileMethod = !kIsDebugBuild;
+
 static double Percentage(size_t x, size_t y) {
   return 100.0 * (static_cast<double>(x)) / (static_cast<double>(x + y));
 }
@@ -2024,7 +2026,7 @@ void CompilerDriver::CompileMethod(const DexFile::CodeItem* code_item, uint32_t
                                    const DexFile& dex_file,
                                    DexToDexCompilationLevel dex_to_dex_compilation_level) {
   CompiledMethod* compiled_method = NULL;
-  uint64_t start_ns = NanoTime();
+  uint64_t start_ns = kTimeCompileMethod ? NanoTime() : 0;
 
   if ((access_flags & kAccNative) != 0) {
     // Are we interpreting only and have support for generic JNI down calls?
@@ -2052,10 +2054,12 @@ void CompilerDriver::CompileMethod(const DexFile::CodeItem* code_item, uint32_t
                               dex_to_dex_compilation_level);
     }
   }
-  uint64_t duration_ns = NanoTime() - start_ns;
-  if (duration_ns > MsToNs(compiler_->GetMaximumCompilationTimeBeforeWarning()) && !kIsDebugBuild) {
-    LOG(WARNING) << "Compilation of " << PrettyMethod(method_idx, dex_file)
-                 << " took " << PrettyDuration(duration_ns);
+  if (kTimeCompileMethod) {
+    uint64_t duration_ns = NanoTime() - start_ns;
+    if (duration_ns > MsToNs(compiler_->GetMaximumCompilationTimeBeforeWarning())) {
+      LOG(WARNING) << "Compilation of " << PrettyMethod(method_idx, dex_file)
+                   << " took " << PrettyDuration(duration_ns);
+    }
   }
 
   Thread* self = Thread::Current();