Fast compiler: Load globals variables directly from property cells....

src/arm/fast-codegen-arm.cc

Index: src/arm/fast-codegen-arm.cc
===================================================================
--- src/arm/fast-codegen-arm.cc	(revision 3807)
+++ src/arm/fast-codegen-arm.cc	(working copy)
@@ -48,42 +48,48 @@
     PrintF("MapCheck(this)\n");
   }
 
+  ASSERT(info()->has_receiver() && info()->receiver()->IsHeapObject());
+  Handle<HeapObject> object = Handle<HeapObject>::cast(info()->receiver());
+  Handle<Map> map(object->map());
+
   EmitLoadReceiver(r1);
-  __ BranchOnSmi(r1, bailout());
+  __ CheckMap(r1, r3, map, bailout(), false);
+}
 
-  ASSERT(has_receiver() && receiver()->IsHeapObject());
-  Handle<HeapObject> object = Handle<HeapObject>::cast(receiver());
-  Handle<Map> map(object->map());
-  __ ldr(r3, FieldMemOperand(r1, HeapObject::kMapOffset));
-  __ mov(ip, Operand(map));
-  __ cmp(r3, ip);
-  __ b(ne, bailout());
+
+void FastCodeGenerator::EmitGlobalMapCheck() {
+  Comment cmnt(masm(), ";; GlobalMapCheck");
+  if (FLAG_print_ir) {
+    PrintF(";; GlobalMapCheck()");
+  }
+
+  ASSERT(info()->has_global_object());
+  Handle<Map> map(info()->global_object()->map());
+
+  __ ldr(r3, CodeGenerator::GlobalObject());
+  __ CheckMap(r3, r3, map, bailout(), true);
 }
 
 
-void FastCodeGenerator::EmitGlobalVariableLoad(Handle<String> name) {
-  // Compile global variable accesses as load IC calls.  The only live
-  // registers are cp (context) and possibly r1 (this).  Both are also saved
-  // in the stack and cp is preserved by the call.
-  __ ldr(ip, CodeGenerator::GlobalObject());
-  __ push(ip);
-  __ mov(r2, Operand(name));
-  Handle<Code> ic(Builtins::builtin(Builtins::LoadIC_Initialize));
-  __ Call(ic, RelocInfo::CODE_TARGET_CONTEXT);
-  if (has_this_properties()) {
-    // Restore this.
-    EmitLoadReceiver(r1);
+void FastCodeGenerator::EmitGlobalVariableLoad(Handle<Object> cell) {
+  ASSERT(cell->IsJSGlobalPropertyCell());
+  __ mov(r0, Operand(cell));
+  __ ldr(r0, FieldMemOperand(r0, JSGlobalPropertyCell::kValueOffset));
+  if (FLAG_debug_code) {
+    __ mov(ip, Operand(Factory::the_hole_value()));
+    __ cmp(r0, ip);
+    __ Check(ne, "DontDelete cells can't contain the hole");
   }
 }
 
 
 void FastCodeGenerator::EmitThisPropertyStore(Handle<String> name) {
   LookupResult lookup;
-  receiver()->Lookup(*name, &lookup);
+  info()->receiver()->Lookup(*name, &lookup);
 
-  ASSERT(lookup.holder() == *receiver());
+  ASSERT(lookup.holder() == *info()->receiver());
   ASSERT(lookup.type() == FIELD);
-  Handle<Map> map(Handle<HeapObject>::cast(receiver())->map());
+  Handle<Map> map(Handle<HeapObject>::cast(info()->receiver())->map());
   int index = lookup.GetFieldIndex() - map->inobject_properties();
   int offset = index * kPointerSize;
 
@@ -102,9 +108,9 @@
 }
 
 
-void FastCodeGenerator::Generate(CompilationInfo* info) {
+void FastCodeGenerator::Generate(CompilationInfo* compilation_info) {
   ASSERT(info_ == NULL);
-  info_ = info;
+  info_ = compilation_info;
 
   // Save the caller's frame pointer and set up our own.
   Comment prologue_cmnt(masm(), ";; Prologue");
@@ -114,8 +120,12 @@
   // this point.
 
   // Receiver (this) is allocated to r1 if there are this properties.
-  if (has_this_properties()) EmitReceiverMapCheck();
+  if (info()->has_this_properties()) EmitReceiverMapCheck();
 
+  // If there is a global variable access check if the global object
+  // is the same as at lazy-compilation time.
+  if (info()->has_globals()) EmitGlobalMapCheck();
+
   VisitStatements(function()->body());
 
   Comment return_cmnt(masm(), ";; Return(<undefined>)");