Object pool with support for untagged entries.

runtime/vm/assembler_x64.cc

Index: runtime/vm/assembler_x64.cc
diff --git a/runtime/vm/assembler_x64.cc b/runtime/vm/assembler_x64.cc
index 660c0473cabffe85c6c7087613abd4fec271f186..804dcf21a18652018d240d6ac95f420bedfe4f42 100644
--- a/runtime/vm/assembler_x64.cc
+++ b/runtime/vm/assembler_x64.cc
@@ -32,30 +32,29 @@ Assembler::Assembler(bool use_far_branches)
   if (isolate != Dart::vm_isolate()) {
     // These objects and labels need to be accessible through every pool-pointer
     // at the same index.
-    intptr_t index =
-        object_pool_.AddObject(Object::null_object(), kNotPatchable);
+    intptr_t index = object_pool_wrapper_.AddObject(Object::null_object());
     ASSERT(index == 0);
 
-    index = object_pool_.AddObject(Bool::True(), kNotPatchable);
+    index = object_pool_wrapper_.AddObject(Bool::True());
     ASSERT(index == 1);
 
-    index = object_pool_.AddObject(Bool::False(), kNotPatchable);
+    index = object_pool_wrapper_.AddObject(Bool::False());
     ASSERT(index == 2);
 
     const Smi& vacant = Smi::Handle(Smi::New(0xfa >> kSmiTagShift));
     StubCode* stub_code = isolate->stub_code();
     if (stub_code->UpdateStoreBuffer_entry() != NULL) {
-      object_pool_.AddExternalLabel(&stub_code->UpdateStoreBufferLabel(),
-                                    kNotPatchable);
+      object_pool_wrapper_.AddExternalLabel(
+          &stub_code->UpdateStoreBufferLabel(), kNotPatchable);
     } else {
-      object_pool_.AddObject(vacant, kNotPatchable);
+      object_pool_wrapper_.AddObject(vacant);
     }
 
     if (stub_code->CallToRuntime_entry() != NULL) {
-      object_pool_.AddExternalLabel(&stub_code->CallToRuntimeLabel(),
-                                    kNotPatchable);
+      object_pool_wrapper_.AddExternalLabel(
+          &stub_code->CallToRuntimeLabel(), kNotPatchable);
     } else {
-      object_pool_.AddObject(vacant, kNotPatchable);
+      object_pool_wrapper_.AddObject(vacant);
     }
   }
 }
@@ -95,8 +94,8 @@ void Assembler::LoadExternalLabel(Register dst,
                                   const ExternalLabel* label,
                                   Patchability patchable,
                                   Register pp) {
-  const int32_t offset =
-      Array::element_offset(object_pool_.FindExternalLabel(label, patchable));
+  const int32_t offset = ObjectPool::element_offset(
+      object_pool_wrapper_.FindExternalLabel(label, patchable));
   LoadWordFromPoolOffset(dst, pp, offset - kHeapObjectTag);
 }
 
@@ -115,8 +114,8 @@ void Assembler::call(const ExternalLabel* label) {
 void Assembler::CallPatchable(const ExternalLabel* label) {
   ASSERT(allow_constant_pool());
   intptr_t call_start = buffer_.GetPosition();
-  const int32_t offset =
-      Array::element_offset(object_pool_.FindExternalLabel(label, kPatchable));
+  const int32_t offset = ObjectPool::element_offset(
+      object_pool_wrapper_.FindExternalLabel(label, kPatchable));
   call(Address::AddressBaseImm32(PP, offset - kHeapObjectTag));
   ASSERT((buffer_.GetPosition() - call_start) == kCallExternalLabelSize);
 }
@@ -126,8 +125,8 @@ void Assembler::Call(const ExternalLabel* label, Register pp) {
   if (Isolate::Current() == Dart::vm_isolate()) {
     call(label);
   } else {
-    const int32_t offset = Array::element_offset(
-        object_pool_.FindExternalLabel(label, kNotPatchable));
+    const int32_t offset = ObjectPool::element_offset(
+        object_pool_wrapper_.FindExternalLabel(label, kNotPatchable));
     call(Address::AddressBaseImm32(pp, offset - kHeapObjectTag));
   }
 }
@@ -2607,8 +2606,8 @@ void Assembler::jmp(const ExternalLabel* label) {
 void Assembler::JmpPatchable(const ExternalLabel* label, Register pp) {
   ASSERT(allow_constant_pool());
   intptr_t call_start = buffer_.GetPosition();
-  const int32_t offset =
-      Array::element_offset(object_pool_.FindExternalLabel(label, kPatchable));
+  const int32_t offset = ObjectPool::element_offset(
+      object_pool_wrapper_.FindExternalLabel(label, kPatchable));
   // Patchable jumps always use a 32-bit immediate encoding.
   jmp(Address::AddressBaseImm32(pp, offset - kHeapObjectTag));
   ASSERT((buffer_.GetPosition() - call_start) == JumpPattern::kLengthInBytes);
@@ -2616,8 +2615,8 @@ void Assembler::JmpPatchable(const ExternalLabel* label, Register pp) {
 
 
 void Assembler::Jmp(const ExternalLabel* label, Register pp) {
-  const int32_t offset = Array::element_offset(
-      object_pool_.FindExternalLabel(label, kNotPatchable));
+  const int32_t offset = ObjectPool::element_offset(
+      object_pool_wrapper_.FindExternalLabel(label, kNotPatchable));
   jmp(Address(pp, offset - kHeapObjectTag));
 }
 
@@ -2817,7 +2816,7 @@ void Assembler::LoadIsolate(Register dst) {
 void Assembler::LoadObject(Register dst, const Object& object, Register pp) {
   if (CanLoadFromObjectPool(object)) {
     const int32_t offset =
-        Array::element_offset(object_pool_.FindObject(object, kNotPatchable));
+        ObjectPool::element_offset(object_pool_wrapper_.FindObject(object));
     LoadWordFromPoolOffset(dst, pp, offset - kHeapObjectTag);
   } else {
     ASSERT((Isolate::Current() == Dart::vm_isolate()) ||
@@ -2852,7 +2851,7 @@ void Assembler::PushObject(const Object& object, Register pp) {
 void Assembler::CompareObject(Register reg, const Object& object, Register pp) {
   if (CanLoadFromObjectPool(object)) {
     const int32_t offset =
-        Array::element_offset(object_pool_.FindObject(object, kNotPatchable));
+        ObjectPool::element_offset(object_pool_wrapper_.FindObject(object));
     cmpq(reg, Address(pp, offset-kHeapObjectTag));
   } else {
     CompareImmediate(
@@ -2863,8 +2862,7 @@ void Assembler::CompareObject(Register reg, const Object& object, Register pp) {
 
 intptr_t Assembler::FindImmediate(int64_t imm) {
   ASSERT(Isolate::Current() != Dart::vm_isolate());
-  const Smi& smi = Smi::Handle(reinterpret_cast<RawSmi*>(imm));
-  return object_pool_.FindObject(smi, kNotPatchable);
+  return object_pool_wrapper_.FindImmediate(imm);
 }
 
 
@@ -2882,16 +2880,8 @@ void Assembler::LoadImmediate(Register reg, const Immediate& imm, Register pp) {
   if (CanLoadImmediateFromPool(imm, pp)) {
     // It's a 64-bit constant and we're not in the VM isolate, so load from
     // object pool.
-    int64_t val = imm.value();
-    // Save the bits that must be masked-off for the SmiTag
-    int64_t val_smi_tag = val & kSmiTagMask;
-    val &= ~kSmiTagMask;  // Mask off the tag bits.
-    const int32_t offset = Array::element_offset(FindImmediate(val));
+    int32_t offset = ObjectPool::element_offset(FindImmediate(imm.value()));
     LoadWordFromPoolOffset(reg, pp, offset - kHeapObjectTag);
-    if (val_smi_tag != 0) {
-      // Add back the tag bits.
-      orq(reg, Immediate(val_smi_tag));
-    }
   } else {
     movq(reg, imm);
   }