Merge "Revert "Revert "Revert "Revert "JIT root tables."""""

1 files changed, 36 insertions, 6 deletions

diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index 7e4ad267c8..38494370ab 100644
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -1012,6 +1012,7 @@ CodeGeneratorX86::CodeGeneratorX86(HGraph* graph,
       simple_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
       string_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
       type_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
+      jit_string_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
       constant_area_start_(-1),
       fixups_to_jump_tables_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
       method_address_offset_(-1) {
@@ -6218,16 +6219,15 @@ HLoadString::LoadKind CodeGeneratorX86::GetSupportedLoadStringKind(
       break;
     case HLoadString::LoadKind::kDexCacheViaMethod:
       break;
+    case HLoadString::LoadKind::kJitTableAddress:
+      DCHECK(Runtime::Current()->UseJitCompilation());
+      break;
   }
   return desired_string_load_kind;
 }
 
 void LocationsBuilderX86::VisitLoadString(HLoadString* load) {
-  LocationSummary::CallKind call_kind = (load->NeedsEnvironment() || kEmitCompilerReadBarrier)
-      ? ((load->GetLoadKind() == HLoadString::LoadKind::kDexCacheViaMethod)
-          ? LocationSummary::kCallOnMainOnly
-          : LocationSummary::kCallOnSlowPath)
-      : LocationSummary::kNoCall;
+  LocationSummary::CallKind call_kind = CodeGenerator::GetLoadStringCallKind(load);
   LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(load, call_kind);
   HLoadString::LoadKind load_kind = load->GetLoadKind();
   if (load_kind == HLoadString::LoadKind::kBootImageLinkTimePcRelative ||
@@ -6252,6 +6252,14 @@ void LocationsBuilderX86::VisitLoadString(HLoadString* load) {
   }
 }
 
+Label* CodeGeneratorX86::NewJitRootStringPatch(const DexFile& dex_file, uint32_t dex_index) {
+  jit_string_roots_.Overwrite(StringReference(&dex_file, dex_index), /* placeholder */ 0u);
+  // Add a patch entry and return the label.
+  jit_string_patches_.emplace_back(dex_file, dex_index);
+  PatchInfo<Label>* info = &jit_string_patches_.back();
+  return &info->label;
+}
+
 void InstructionCodeGeneratorX86::VisitLoadString(HLoadString* load) {
   LocationSummary* locations = load->GetLocations();
   Location out_loc = locations->Out();
@@ -6280,7 +6288,7 @@ void InstructionCodeGeneratorX86::VisitLoadString(HLoadString* load) {
       Register method_address = locations->InAt(0).AsRegister<Register>();
       Address address = Address(method_address, CodeGeneratorX86::kDummy32BitOffset);
       Label* fixup_label = codegen_->NewStringBssEntryPatch(load);
-      // /* GcRoot<mirror::Class> */ out = *address  /* PC-relative */
+      // /* GcRoot<mirror::String> */ out = *address  /* PC-relative */
       GenerateGcRootFieldLoad(load, out_loc, address, fixup_label, kCompilerReadBarrierOption);
       SlowPathCode* slow_path = new (GetGraph()->GetArena()) LoadStringSlowPathX86(load);
       codegen_->AddSlowPath(slow_path);
@@ -6289,6 +6297,14 @@ void InstructionCodeGeneratorX86::VisitLoadString(HLoadString* load) {
       __ Bind(slow_path->GetExitLabel());
       return;
     }
+    case HLoadString::LoadKind::kJitTableAddress: {
+      Address address = Address::Absolute(CodeGeneratorX86::kDummy32BitOffset);
+      Label* fixup_label = codegen_->NewJitRootStringPatch(
+          load->GetDexFile(), load->GetStringIndex());
+      // /* GcRoot<mirror::String> */ out = *address
+      GenerateGcRootFieldLoad(load, out_loc, address, fixup_label, kCompilerReadBarrierOption);
+      return;
+    }
     default:
       break;
   }
@@ -7736,6 +7752,20 @@ void CodeGeneratorX86::MoveFromReturnRegister(Location target, Primitive::Type t
   }
 }
 
+void CodeGeneratorX86::EmitJitRootPatches(uint8_t* code, const uint8_t* roots_data) {
+  for (const PatchInfo<Label>& info : jit_string_patches_) {
+    const auto& it = jit_string_roots_.find(StringReference(&info.dex_file, info.index));
+    DCHECK(it != jit_string_roots_.end());
+    size_t index_in_table = it->second;
+    uint32_t code_offset = info.label.Position() - kLabelPositionToLiteralOffsetAdjustment;
+    uintptr_t address =
+        reinterpret_cast<uintptr_t>(roots_data) + index_in_table * sizeof(GcRoot<mirror::Object>);
+    typedef __attribute__((__aligned__(1))) uint32_t unaligned_uint32_t;
+    reinterpret_cast<unaligned_uint32_t*>(code + code_offset)[0] =
+       dchecked_integral_cast<uint32_t>(address);
+  }
+}
+
 #undef __
 
 }  // namespace x86