Use direct jump and call instruction for X64 when the deoptimization entries are in the code range

src/x64/assembler-x64-inl.h

Index: src/x64/assembler-x64-inl.h
===================================================================
--- src/x64/assembler-x64-inl.h	(revision 13740)
+++ src/x64/assembler-x64-inl.h	(working copy)
@@ -86,6 +86,20 @@
 }
 
 
+void Assembler::emit_runtime_entry(Address entry, RelocInfo::Mode rmode) {

[danno, 2013/03/07 14:57:23]

I don't think you need to keep the runtime_entries_ table at all. Just subtract
the CodeRange base from entry, that gives you a 32-offset that you can store
directly in the runtime entry until it's copied into the code object.
runtime_entry_at on x64 return needs to return the offset + CodeRange.start. 

[haitao.feng, 2013/03/08 05:30:05]

Done.

+  ASSERT(RelocInfo::IsRuntimeEntry(rmode));
+  RecordRelocInfo(rmode);
+  int current = runtime_entries_.length();
+  if (current > 0 && runtime_entries_.last() == entry) {
+    // Optimization if we keep jumping to the same entry.
+    emitl(current - 1);
+  } else {
+    runtime_entries_.Add(entry);
+    emitl(current);
+  }
+}
+
+
 void Assembler::emit_rex_64(Register reg, Register rm_reg) {
   emit(0x48 | reg.high_bit() << 2 | rm_reg.high_bit());
 }
@@ -208,6 +222,11 @@
   return code_targets_[Memory::int32_at(pc)];
 }
 
+
+Address Assembler::runtime_entry_at(Address pc) {
+  return runtime_entries_[Memory::int32_at(pc)];
+}
+
 // -----------------------------------------------------------------------------
 // Implementation of RelocInfo
 
@@ -217,7 +236,7 @@
     // absolute code pointer inside code object moves with the code object.
     Memory::Address_at(pc_) += static_cast<int32_t>(delta);
     CPU::FlushICache(pc_, sizeof(Address));
-  } else if (IsCodeTarget(rmode_)) {
+  } else if (IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_)) {
     Memory::int32_at(pc_) -= static_cast<int32_t>(delta);
     CPU::FlushICache(pc_, sizeof(int32_t));
   } else if (rmode_ == CODE_AGE_SEQUENCE) {
@@ -231,17 +250,13 @@
 
 
 Address RelocInfo::target_address() {
-  ASSERT(IsCodeTarget(rmode_) || rmode_ == RUNTIME_ENTRY);
-  if (IsCodeTarget(rmode_)) {
-    return Assembler::target_address_at(pc_);
-  } else {
-    return Memory::Address_at(pc_);
-  }
+  ASSERT(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_));
+  return Assembler::target_address_at(pc_);
 }
 
 
 Address RelocInfo::target_address_address() {
-  ASSERT(IsCodeTarget(rmode_) || rmode_ == RUNTIME_ENTRY
+  ASSERT(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_)
                               || rmode_ == EMBEDDED_OBJECT
                               || rmode_ == EXTERNAL_REFERENCE);
   return reinterpret_cast<Address>(pc_);
@@ -258,17 +273,12 @@
 
 
 void RelocInfo::set_target_address(Address target, WriteBarrierMode mode) {
-  ASSERT(IsCodeTarget(rmode_) || rmode_ == RUNTIME_ENTRY);
-  if (IsCodeTarget(rmode_)) {
-    Assembler::set_target_address_at(pc_, target);
+  ASSERT(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_));
+  Assembler::set_target_address_at(pc_, target);
+  if (mode == UPDATE_WRITE_BARRIER && host() != NULL && IsCodeTarget(rmode_)) {
     Object* target_code = Code::GetCodeFromTargetAddress(target);
-    if (mode == UPDATE_WRITE_BARRIER && host() != NULL) {
-      host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(
-          host(), this, HeapObject::cast(target_code));
-    }
-  } else {
-    Memory::Address_at(pc_) = target;
-    CPU::FlushICache(pc_, sizeof(Address));
+    host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(
+        host(), this, HeapObject::cast(target_code));
   }
 }
 
@@ -289,6 +299,17 @@
 }
 
 
+bool RelocInfo::NeedsInitializeRuntimeEntry() {
+  return true;
+}
+
+
+Address RelocInfo::target_runtime_entry(Assembler* origin) {
+  ASSERT(IsRuntimeEntry(rmode_));
+  return origin->runtime_entry_at(pc_);
+}
+
+
 Object** RelocInfo::target_object_address() {
   ASSERT(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);
   return reinterpret_cast<Object**>(pc_);
@@ -443,7 +464,7 @@
              Isolate::Current()->debug()->has_break_points()) {
     visitor->VisitDebugTarget(this);
 #endif
-  } else if (mode == RelocInfo::RUNTIME_ENTRY) {
+  } else if (RelocInfo::IsRuntimeEntry(mode)) {
     visitor->VisitRuntimeEntry(this);
   }
 }
@@ -472,7 +493,7 @@
               IsPatchedDebugBreakSlotSequence()))) {
     StaticVisitor::VisitDebugTarget(heap, this);
 #endif
-  } else if (mode == RelocInfo::RUNTIME_ENTRY) {
+  } else if (RelocInfo::IsRuntimeEntry(mode)) {
     StaticVisitor::VisitRuntimeEntry(this);
   }
 }