Make closures optimizable by Crankshaft compiler.

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index af2b92a1bb80d1e412b4cdf304fcc13cb6228352..b43174597cf029fe02e4e14dffe32959e58bd4a5 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -1817,6 +1817,17 @@ void LCodeGen::DoStoreGlobal(LStoreGlobal* instr) {
 }
 
 
+void LCodeGen::DoLoadContextSlot(LLoadContextSlot* instr) {
+  // TODO(antonm): load a context with a separate instruction.
+  Register result = ToRegister(instr->result());
+  HLoadContextSlot* hinstr = instr->hydrogen();

[Kevin Millikin (Chromium), 2010/12/20 12:05:44]

It's typical for the Lithium instructions to have accessors like slot_index and
context_chain_length that just forward to the hydrogen instruction.

[antonm, 2010/12/20 20:39:24]

Done.

+  Comment(";;; Load context slot %d at %d",

[Kevin Millikin (Chromium), 2010/12/20 12:05:44]

There will automatically be a comment with the printed representation of the
instruction without having to emit it explicitly.

You should just have to override the print data function for LLoadContextSlot to
print the height and offset.

[antonm, 2010/12/20 20:39:24]

Done.

+      hinstr->slot_index(), hinstr->context_chain_length());
+  __ LoadContext(result, hinstr->context_chain_length());
+  __ mov(result, ContextOperand(result, hinstr->slot_index()));
+}
+
+
 void LCodeGen::DoLoadNamedField(LLoadNamedField* instr) {
   Register object = ToRegister(instr->input());
   Register result = ToRegister(instr->result());
@@ -2910,13 +2921,13 @@ void LCodeGen::DoCheckMap(LCheckMap* instr) {
 }
 
 
-void LCodeGen::LoadPrototype(Register result, Handle<JSObject> prototype) {
-  if (Heap::InNewSpace(*prototype)) {
+void LCodeGen::LoadHeapObject(Register result, Handle<HeapObject> object) {
+  if (Heap::InNewSpace(*object)) {
     Handle<JSGlobalPropertyCell> cell =
-        Factory::NewJSGlobalPropertyCell(prototype);
+        Factory::NewJSGlobalPropertyCell(object);
     __ mov(result, Operand::Cell(cell));
   } else {
-    __ mov(result, prototype);
+    __ mov(result, object);
   }
 }
 
@@ -2929,7 +2940,7 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
   Handle<JSObject> current_prototype(JSObject::cast(receiver_map->prototype()));
 
   // Load prototype object.
-  LoadPrototype(reg, current_prototype);
+  LoadHeapObject(reg, current_prototype);
 
   // Check prototype maps up to the holder.
   while (!current_prototype.is_identical_to(holder)) {
@@ -2939,7 +2950,7 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
     current_prototype =
         Handle<JSObject>(JSObject::cast(current_prototype->GetPrototype()));
     // Load next prototype object.
-    LoadPrototype(reg, current_prototype);
+    LoadHeapObject(reg, current_prototype);
   }
 
   // Check the holder map.