commit 7a5a7c3add22af1b9d9ffd03ed664092eb6351c6
author Vladimir Marko <vmarko@google.com> Mon Mar 08 10:02:15 2021 +0000
committer Vladimir Marko <vmarko@google.com> Mon Mar 08 14:29:37 2021 +0000
tree 6707b05142e09e7af4270b28ea86f26465600ef9
parent 987a8eaa3b34dc4be71ee15e3ec56cc16ec8e5d3

arm/arm64: Add comment to JNI assemblers' TestGcMarking.

Test: m
Bug: 172332525
Change-Id: I6515f326d331e9de3e4c12b48c680dad4272fd60

compiler/utils/arm/jni_macro_assembler_arm_vixl.cc

diff --git a/compiler/utils/arm/jni_macro_assembler_arm_vixl.cc b/compiler/utils/arm/jni_macro_assembler_arm_vixl.cc
index 1ebc850..70a1939 100644
--- a/compiler/utils/arm/jni_macro_assembler_arm_vixl.cc
+++ b/compiler/utils/arm/jni_macro_assembler_arm_vixl.cc
@@ -999,6 +999,7 @@
   DCHECK_EQ(Thread::IsGcMarkingSize(), 4u);
   DCHECK(kUseReadBarrier);
   if (kUseBakerReadBarrier) {
+    // TestGcMarking() is used in the JNI stub entry when the marking register is up to date.
     if (kIsDebugBuild && emit_run_time_checks_in_debug_mode_) {
       vixl32::Register temp = temps.Acquire();
       asm_.GenerateMarkingRegisterCheck(temp);

compiler/utils/arm64/jni_macro_assembler_arm64.cc

diff --git a/compiler/utils/arm64/jni_macro_assembler_arm64.cc b/compiler/utils/arm64/jni_macro_assembler_arm64.cc
index 3185f1e..c4dbd3f 100644
--- a/compiler/utils/arm64/jni_macro_assembler_arm64.cc
+++ b/compiler/utils/arm64/jni_macro_assembler_arm64.cc
@@ -724,6 +724,7 @@
   DCHECK_EQ(Thread::IsGcMarkingSize(), 4u);
   DCHECK(kUseReadBarrier);
   if (kUseBakerReadBarrier) {
+    // TestGcMarking() is used in the JNI stub entry when the marking register is up to date.
     if (kIsDebugBuild && emit_run_time_checks_in_debug_mode_) {
       Register temp = temps.AcquireW();
       asm_.GenerateMarkingRegisterCheck(temp);