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

Test: 626-set-resolved-string, test-art-host, test-art-target
Test: run-libcore-tests.sh
Test: phone boots and runs

This reverts commit 3395fbc20bcd20948bec8958db91b304c17cacd8.

Change-Id: I104b73d093e3eb6a271d564cfdb9ab09c1c8cf24
diff --git a/compiler/optimizing/code_generator_arm64.cc b/compiler/optimizing/code_generator_arm64.cc
index 4ab6065..2b575f7 100644
--- a/compiler/optimizing/code_generator_arm64.cc
+++ b/compiler/optimizing/code_generator_arm64.cc
@@ -1158,7 +1158,9 @@
                                graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
       pc_relative_type_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
       boot_image_address_patches_(std::less<uint32_t>(),
-                                  graph->GetArena()->Adapter(kArenaAllocCodeGenerator)) {
+                                  graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
+      jit_string_patches_(StringReferenceValueComparator(),
+                          graph->GetArena()->Adapter(kArenaAllocCodeGenerator)) {
   // Save the link register (containing the return address) to mimic Quick.
   AddAllocatedRegister(LocationFrom(lr));
 }
@@ -4155,6 +4157,14 @@
   return DeduplicateUint64Literal(address);
 }
 
+vixl::aarch64::Literal<uint32_t>* CodeGeneratorARM64::DeduplicateJitStringLiteral(
+    const DexFile& dex_file, uint32_t string_index) {
+  jit_string_roots_.Overwrite(StringReference(&dex_file, string_index), /* placeholder */ 0u);
+  return jit_string_patches_.GetOrCreate(
+      StringReference(&dex_file, string_index),
+      [this]() { return __ CreateLiteralDestroyedWithPool<uint32_t>(/* placeholder */ 0u); });
+}
+
 void CodeGeneratorARM64::EmitAdrpPlaceholder(vixl::aarch64::Label* fixup_label,
                                              vixl::aarch64::Register reg) {
   DCHECK(reg.IsX());
@@ -4540,16 +4550,15 @@
       break;
     case HLoadString::LoadKind::kDexCacheViaMethod:
       break;
+    case HLoadString::LoadKind::kJitTableAddress:
+      DCHECK(Runtime::Current()->UseJitCompilation());
+      break;
   }
   return desired_string_load_kind;
 }
 
 void LocationsBuilderARM64::VisitLoadString(HLoadString* load) {
-  LocationSummary::CallKind call_kind = load->NeedsEnvironment()
-      ? ((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);
   if (load->GetLoadKind() == HLoadString::LoadKind::kDexCacheViaMethod) {
     InvokeRuntimeCallingConvention calling_convention;
@@ -4575,6 +4584,7 @@
 
 void InstructionCodeGeneratorARM64::VisitLoadString(HLoadString* load) {
   Register out = OutputRegister(load);
+  Location out_loc = load->GetLocations()->Out();
 
   switch (load->GetLoadKind()) {
     case HLoadString::LoadKind::kBootImageLinkTimeAddress:
@@ -4611,9 +4621,9 @@
       // Add LDR with its PC-relative String patch.
       vixl::aarch64::Label* ldr_label =
           codegen_->NewPcRelativeStringPatch(dex_file, string_index, adrp_label);
-      // /* GcRoot<mirror::Class> */ out = *(base_address + offset)  /* PC-relative */
+      // /* GcRoot<mirror::String> */ out = *(base_address + offset)  /* PC-relative */
       GenerateGcRootFieldLoad(load,
-                              load->GetLocations()->Out(),
+                              out_loc,
                               temp,
                               /* offset placeholder */ 0u,
                               ldr_label,
@@ -4625,6 +4635,17 @@
       __ Bind(slow_path->GetExitLabel());
       return;
     }
+    case HLoadString::LoadKind::kJitTableAddress: {
+      __ Ldr(out, codegen_->DeduplicateJitStringLiteral(load->GetDexFile(),
+                                                        load->GetStringIndex()));
+      GenerateGcRootFieldLoad(load,
+                              out_loc,
+                              out.X(),
+                              /* offset */ 0,
+                              /* fixup_label */ nullptr,
+                              kCompilerReadBarrierOption);
+      return;
+    }
     default:
       break;
   }
@@ -5744,7 +5765,19 @@
   }
 }
 
-
+void CodeGeneratorARM64::EmitJitRootPatches(uint8_t* code, const uint8_t* roots_data) {
+  for (const auto& entry : jit_string_patches_) {
+    const auto& it = jit_string_roots_.find(entry.first);
+    DCHECK(it != jit_string_roots_.end());
+    size_t index_in_table = it->second;
+    vixl::aarch64::Literal<uint32_t>* literal = entry.second;
+    uint32_t literal_offset = literal->GetOffset();
+    uintptr_t address =
+        reinterpret_cast<uintptr_t>(roots_data) + index_in_table * sizeof(GcRoot<mirror::Object>);
+    uint8_t* data = code + literal_offset;
+    reinterpret_cast<uint32_t*>(data)[0] = dchecked_integral_cast<uint32_t>(address);
+  }
+}
 
 #undef __
 #undef QUICK_ENTRY_POINT