Avoid read barrier for image HLoadClass

Concurrent copying baker:

X86_64 core-optimizing-pic.oat: 28583112 -> 27906824 (2.4% smaller)

Around 0.4% of 2.4% is from re-enabling kBootImageLinkTimeAddress,
kBootImageLinkTimePcRelative, and kBootImageAddress.

N6P boot.oat 32: 73042140 -> 71891956 (1.57% smaller)
N6P boot.oat 64: 83831608 -> 82531456 (1.55% smaller)

EAAC: 1252 -> 1245 (32 samples)

Bug: 29516974

Test: test-art-host CC baker, N6P booting

Change-Id: I9a196cf0157058836981c43c93872e9f0c4919aa

1 files changed, 10 insertions, 2 deletions

diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index 19e499ba8c..149a71d1b9 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -5461,7 +5461,8 @@ class HLoadClass FINAL : public HInstruction {
              bool is_referrers_class,
              uint32_t dex_pc,
              bool needs_access_check,
-             bool is_in_dex_cache)
+             bool is_in_dex_cache,
+             bool is_in_boot_image)
       : HInstruction(SideEffectsForArchRuntimeCalls(), dex_pc),
         special_input_(HUserRecord<HInstruction*>(current_method)),
         type_index_(type_index),
@@ -5475,6 +5476,7 @@ class HLoadClass FINAL : public HInstruction {
         is_referrers_class ? LoadKind::kReferrersClass : LoadKind::kDexCacheViaMethod);
     SetPackedFlag<kFlagNeedsAccessCheck>(needs_access_check);
     SetPackedFlag<kFlagIsInDexCache>(is_in_dex_cache);
+    SetPackedFlag<kFlagIsInBootImage>(is_in_boot_image);
     SetPackedFlag<kFlagGenerateClInitCheck>(false);
   }
 
@@ -5565,6 +5567,7 @@ class HLoadClass FINAL : public HInstruction {
   bool IsReferrersClass() const { return GetLoadKind() == LoadKind::kReferrersClass; }
   bool NeedsAccessCheck() const { return GetPackedFlag<kFlagNeedsAccessCheck>(); }
   bool IsInDexCache() const { return GetPackedFlag<kFlagIsInDexCache>(); }
+  bool IsInBootImage() const { return GetPackedFlag<kFlagIsInBootImage>(); }
   bool MustGenerateClinitCheck() const { return GetPackedFlag<kFlagGenerateClInitCheck>(); }
 
   void MarkInDexCache() {
@@ -5574,6 +5577,10 @@ class HLoadClass FINAL : public HInstruction {
     SetSideEffects(SideEffects::None());
   }
 
+  void MarkInBootImage() {
+    SetPackedFlag<kFlagIsInBootImage>(true);
+  }
+
   void AddSpecialInput(HInstruction* special_input);
 
   using HInstruction::GetInputRecords;  // Keep the const version visible.
@@ -5591,9 +5598,10 @@ class HLoadClass FINAL : public HInstruction {
  private:
   static constexpr size_t kFlagNeedsAccessCheck    = kNumberOfGenericPackedBits;
   static constexpr size_t kFlagIsInDexCache        = kFlagNeedsAccessCheck + 1;
+  static constexpr size_t kFlagIsInBootImage       = kFlagIsInDexCache + 1;
   // Whether this instruction must generate the initialization check.
   // Used for code generation.
-  static constexpr size_t kFlagGenerateClInitCheck = kFlagIsInDexCache + 1;
+  static constexpr size_t kFlagGenerateClInitCheck = kFlagIsInBootImage + 1;
   static constexpr size_t kFieldLoadKind           = kFlagGenerateClInitCheck + 1;
   static constexpr size_t kFieldLoadKindSize =
       MinimumBitsToStore(static_cast<size_t>(LoadKind::kLast));