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_arm64.cc

diff --git a/compiler/optimizing/code_generator_arm64.cc b/compiler/optimizing/code_generator_arm64.cc
index 13bbffa..1380596 100644
--- a/compiler/optimizing/code_generator_arm64.cc
+++ b/compiler/optimizing/code_generator_arm64.cc
@@ -1488,6 +1488,14 @@
   MacroAssembler* masm = GetVIXLAssembler();
   __ Bind(&frame_entry_label_);
 
+  if (GetCompilerOptions().CountHotnessInCompiledCode()) {
+    UseScratchRegisterScope temps(masm);
+    Register temp = temps.AcquireX();
+    __ Ldrh(temp, MemOperand(kArtMethodRegister, ArtMethod::HotnessCountOffset().Int32Value()));
+    __ Add(temp, temp, 1);
+    __ Strh(temp, MemOperand(kArtMethodRegister, ArtMethod::HotnessCountOffset().Int32Value()));
+  }
+
   bool do_overflow_check =
       FrameNeedsStackCheck(GetFrameSize(), InstructionSet::kArm64) || !IsLeafMethod();
   if (do_overflow_check) {
@@ -3501,6 +3509,15 @@
   HLoopInformation* info = block->GetLoopInformation();
 
   if (info != nullptr && info->IsBackEdge(*block) && info->HasSuspendCheck()) {
+    if (codegen_->GetCompilerOptions().CountHotnessInCompiledCode()) {
+      UseScratchRegisterScope temps(GetVIXLAssembler());
+      Register temp1 = temps.AcquireX();
+      Register temp2 = temps.AcquireX();
+      __ Ldr(temp1, MemOperand(sp, 0));
+      __ Ldrh(temp2, MemOperand(temp1, ArtMethod::HotnessCountOffset().Int32Value()));
+      __ Add(temp2, temp2, 1);
+      __ Strh(temp2, MemOperand(temp1, ArtMethod::HotnessCountOffset().Int32Value()));
+    }
     GenerateSuspendCheck(info->GetSuspendCheck(), successor);
     return;
   }