commit 8d728324571b720a952b297787eed70c7a1d1acb
author Nicolas Geoffray <ngeoffray@google.com> Thu Jan 18 22:44:32 2018 +0000
committer Nicolas Geoffray <ngeoffray@google.com> Mon Jan 29 09:34:05 2018 +0000
tree f24a774aa56c236f2f756b1b439e4c61830bec56
parent 0530796b73d0a33a5df27e3a7765c0835994769a

Add compiler option for counting hotness in compiled code.

For eventually easier profiling of boot classpath and
system server.

bug: 30934496
Test: 674-hotness-compiled

Change-Id: I0f63c644527b74f6ef2649f481c2a1c731bb9f21

compiler/optimizing/code_generator_x86_64.cc

diff --git a/compiler/optimizing/code_generator_x86_64.cc b/compiler/optimizing/code_generator_x86_64.cc
index 510eec4..ee5918d 100644
--- a/compiler/optimizing/code_generator_x86_64.cc
+++ b/compiler/optimizing/code_generator_x86_64.cc
@@ -1268,6 +1268,12 @@
       && !FrameNeedsStackCheck(GetFrameSize(), InstructionSet::kX86_64);
   DCHECK(GetCompilerOptions().GetImplicitStackOverflowChecks());
 
+  if (GetCompilerOptions().CountHotnessInCompiledCode()) {
+    __ addw(Address(CpuRegister(kMethodRegisterArgument),
+                    ArtMethod::HotnessCountOffset().Int32Value()),
+            Immediate(1));
+  }
+
   if (!skip_overflow_check) {
     size_t reserved_bytes = GetStackOverflowReservedBytes(InstructionSet::kX86_64);
     __ testq(CpuRegister(RAX), Address(CpuRegister(RSP), -static_cast<int32_t>(reserved_bytes)));
@@ -1459,6 +1465,11 @@
 
   HLoopInformation* info = block->GetLoopInformation();
   if (info != nullptr && info->IsBackEdge(*block) && info->HasSuspendCheck()) {
+    if (codegen_->GetCompilerOptions().CountHotnessInCompiledCode()) {
+      __ movq(CpuRegister(TMP), Address(CpuRegister(RSP), 0));
+      __ addw(Address(CpuRegister(TMP), ArtMethod::HotnessCountOffset().Int32Value()),
+              Immediate(1));
+    }
     GenerateSuspendCheck(info->GetSuspendCheck(), successor);
     return;
   }