commit 97c46466aea25ab63a99b3d1afc558f0d9f55abb
author Roland Levillain <rpl@google.com> Thu May 11 14:04:03 2017 +0100
committer Roland Levillain <rpl@google.com> Tue Jul 11 17:43:27 2017 +0100
tree afd225f51d28a77329bc2590a025400e088f260c
parent 00cca3a275562d110a8b35094b9b12fac37f67ab

Introduce a Marking Register in ARM64 code generation.

When generating code for ARM64, maintain the status of
Thread::Current()->GetIsGcMarking() in register X20,
dubbed MR (Marking Register), and check the value of that
register (instead of loading and checking a read barrier
marking entrypoint) in read barriers.

Test: m test-art-target
Test: m test-art-target with tree built with ART_USE_READ_BARRIER=false
Test: ARM64 device boot test
Bug: 37707231
Change-Id: Ibe9bc5c99a2176b0a0476e9e9ad7fcc9f745017b

compiler/optimizing/code_generator_arm.cc

diff --git a/compiler/optimizing/code_generator_arm.cc b/compiler/optimizing/code_generator_arm.cc
index 6b9f232..92467fe 100644
--- a/compiler/optimizing/code_generator_arm.cc
+++ b/compiler/optimizing/code_generator_arm.cc
@@ -729,7 +729,7 @@
     } else {
       // Entrypoint is not already loaded, load from the thread.
       int32_t entry_point_offset =
-          CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ref_reg);
+          Thread::ReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ref_reg);
       // This runtime call does not require a stack map.
       arm_codegen->InvokeRuntimeWithoutRecordingPcInfo(entry_point_offset, instruction_, this);
     }
@@ -8428,7 +8428,7 @@
         //     Thread::Current()->pReadBarrierMarkReg12, i.e. pReadBarrierMarkIntrospection.
         DCHECK_EQ(IP, 12);
         const int32_t entry_point_offset =
-            CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(IP);
+            Thread::ReadBarrierMarkEntryPointsOffset<kArmPointerSize>(IP);
         __ LoadFromOffset(kLoadWord, kBakerCcEntrypointRegister, TR, entry_point_offset);
 
         Label return_address;
@@ -8469,7 +8469,7 @@
 
         // temp = Thread::Current()->pReadBarrierMarkReg ## root.reg()
         const int32_t entry_point_offset =
-            CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(root.reg());
+            Thread::ReadBarrierMarkEntryPointsOffset<kArmPointerSize>(root.reg());
         // Loading the entrypoint does not require a load acquire since it is only changed when
         // threads are suspended or running a checkpoint.
         __ LoadFromOffset(kLoadWord, temp.AsRegister<Register>(), TR, entry_point_offset);
@@ -8572,7 +8572,7 @@
     //     Thread::Current()->pReadBarrierMarkReg12, i.e. pReadBarrierMarkIntrospection.
     DCHECK_EQ(IP, 12);
     const int32_t entry_point_offset =
-        CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(IP);
+        Thread::ReadBarrierMarkEntryPointsOffset<kArmPointerSize>(IP);
     __ LoadFromOffset(kLoadWord, kBakerCcEntrypointRegister, TR, entry_point_offset);
 
     Label return_address;
@@ -8655,7 +8655,7 @@
     //     Thread::Current()->pReadBarrierMarkReg16, i.e. pReadBarrierMarkIntrospection.
     DCHECK_EQ(IP, 12);
     const int32_t entry_point_offset =
-        CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(IP);
+        Thread::ReadBarrierMarkEntryPointsOffset<kArmPointerSize>(IP);
     __ LoadFromOffset(kLoadWord, kBakerCcEntrypointRegister, TR, entry_point_offset);
     __ AddConstant(data_reg, obj, data_offset);
 
@@ -8736,7 +8736,7 @@
 
   // temp2 = Thread::Current()->pReadBarrierMarkReg ## ref.reg()
   const int32_t entry_point_offset =
-      CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ref.reg());
+      Thread::ReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ref.reg());
   // Loading the entrypoint does not require a load acquire since it is only changed when
   // threads are suspended or running a checkpoint.
   __ LoadFromOffset(kLoadWord, temp2.AsRegister<Register>(), TR, entry_point_offset);
@@ -8805,7 +8805,7 @@
 
   // temp3 = Thread::Current()->pReadBarrierMarkReg ## ref.reg()
   const int32_t entry_point_offset =
-      CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ref.reg());
+      Thread::ReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ref.reg());
   // Loading the entrypoint does not require a load acquire since it is only changed when
   // threads are suspended or running a checkpoint.
   __ LoadFromOffset(kLoadWord, temp3.AsRegister<Register>(), TR, entry_point_offset);