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

libcore failures:
dalvikvm32 F 11-14 03:04:06 14870 14870 jit_code_cache.cc:310] Check failed: new_string != nullptr

This reverts commit 75afcdd3503a8a8518e5b23d21b6e73306ce39ce.

Change-Id: I5a6b6b48aa79a763d1ff1ba4d85d63811254787d
diff --git a/compiler/optimizing/code_generator_arm.cc b/compiler/optimizing/code_generator_arm.cc
index 035c02e..7c72d00 100644
--- a/compiler/optimizing/code_generator_arm.cc
+++ b/compiler/optimizing/code_generator_arm.cc
@@ -1222,9 +1222,7 @@
                                graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
       pc_relative_type_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
       boot_image_address_patches_(std::less<uint32_t>(),
-                                  graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
-      jit_string_patches_(StringReferenceValueComparator(),
-                          graph->GetArena()->Adapter(kArenaAllocCodeGenerator)) {
+                                  graph->GetArena()->Adapter(kArenaAllocCodeGenerator)) {
   // Always save the LR register to mimic Quick.
   AddAllocatedRegister(Location::RegisterLocation(LR));
 }
@@ -5903,9 +5901,6 @@
     case HLoadString::LoadKind::kBssEntry:
       DCHECK(!Runtime::Current()->UseJitCompilation());
       break;
-    case HLoadString::LoadKind::kJitTableAddress:
-      DCHECK(Runtime::Current()->UseJitCompilation());
-      break;
     case HLoadString::LoadKind::kDexCacheViaMethod:
       break;
   }
@@ -5913,8 +5908,13 @@
 }
 
 void LocationsBuilderARM::VisitLoadString(HLoadString* load) {
-  LocationSummary::CallKind call_kind = CodeGenerator::GetLoadStringCallKind(load);
+  LocationSummary::CallKind call_kind = load->NeedsEnvironment()
+      ? ((load->GetLoadKind() == HLoadString::LoadKind::kDexCacheViaMethod)
+          ? LocationSummary::kCallOnMainOnly
+          : LocationSummary::kCallOnSlowPath)
+      : LocationSummary::kNoCall;
   LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(load, call_kind);
+
   HLoadString::LoadKind load_kind = load->GetLoadKind();
   if (load_kind == HLoadString::LoadKind::kDexCacheViaMethod) {
     locations->SetOut(Location::RegisterLocation(R0));
@@ -5987,13 +5987,6 @@
       __ Bind(slow_path->GetExitLabel());
       return;
     }
-    case HLoadString::LoadKind::kJitTableAddress: {
-      __ LoadLiteral(out, codegen_->DeduplicateJitStringLiteral(load->GetDexFile(),
-                                                                load->GetStringIndex()));
-      // /* GcRoot<mirror::String> */ out = *out
-      GenerateGcRootFieldLoad(load, out_loc, out, /* offset */ 0, kCompilerReadBarrierOption);
-      return;
-    }
     default:
       break;
   }
@@ -7350,14 +7343,6 @@
   return DeduplicateUint32Literal(address, &uint32_literals_);
 }
 
-Literal* CodeGeneratorARM::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 __ NewLiteral<uint32_t>(/* placeholder */ 0u); });
-}
-
 template <LinkerPatch (*Factory)(size_t, const DexFile*, uint32_t, uint32_t)>
 inline void CodeGeneratorARM::EmitPcRelativeLinkerPatches(
     const ArenaDeque<PcRelativePatchInfo>& infos,
@@ -7674,21 +7659,6 @@
   }
 }
 
-void CodeGeneratorARM::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;
-    Literal* literal = entry.second;
-    DCHECK(literal->GetLabel()->IsBound());
-    uint32_t literal_offset = literal->GetLabel()->Position();
-    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