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src/arm/ic-arm.cc

Index: src/arm/ic-arm.cc
diff --git a/src/arm/ic-arm.cc b/src/arm/ic-arm.cc
index ad6eb2c2a876f847a4248f2b2f4f9d8b9c40b920..d54328e4cc198b0f5143ecb2c34af604157afafc 100644
--- a/src/arm/ic-arm.cc
+++ b/src/arm/ic-arm.cc
@@ -127,27 +127,20 @@ static void GenerateDictionaryLoad(MacroAssembler* masm,
 }
 
 
-// Helper function used to check that a value is either not a function
-// or is loaded if it is a function.
-static void GenerateCheckNonFunctionOrLoaded(MacroAssembler* masm,
-                                             Label* miss,
-                                             Register value,
-                                             Register scratch) {
+// Helper function used to check that a value is either not an object
+// or is loaded if it is an object.
+static void GenerateCheckNonObjectOrLoaded(MacroAssembler* masm,
+                                           Label* miss,
+                                           Register value,
+                                           Register scratch) {
   Label done;
   // Check if the value is a Smi.
   __ tst(value, Operand(kSmiTagMask));
   __ b(eq, &done);
-  // Check if the value is a function.
-  __ ldr(scratch, FieldMemOperand(value, HeapObject::kMapOffset));
-  __ ldrb(scratch, FieldMemOperand(scratch, Map::kInstanceTypeOffset));
-  __ cmp(scratch, Operand(JS_FUNCTION_TYPE));
-  __ b(ne, &done);
   // Check if the function has been loaded.

[Mads Ager (chromium), 2009/04/23 19:09:25]

function -> object

-  __ ldr(scratch,
-         FieldMemOperand(value, JSFunction::kSharedFunctionInfoOffset));
-  __ ldr(scratch,
-         FieldMemOperand(scratch, SharedFunctionInfo::kLazyLoadDataOffset));
-  __ cmp(scratch, Operand(Factory::undefined_value()));
+  __ ldr(scratch, FieldMemOperand(value, JSObject::kMapOffset));
+  __ ldrb(scratch, FieldMemOperand(scratch, Map::kBitField2Offset));
+  __ tst(scratch, Operand(1 << Map::kNeedsLoading));
   __ b(ne, miss);
   __ bind(&done);
 }
@@ -277,16 +270,10 @@ static void GenerateNormalHelper(MacroAssembler* masm,
   __ tst(r1, Operand(kSmiTagMask));
   __ b(eq, miss);
 
-  // Check that the value is a JSFunction.

[Mads Ager (chromium), 2009/04/23 19:09:25]

We need this JSFunction check.  We invoke r1 below as a function, so we need to
check that it is a function and otherwise go to the runtime system.

That is the reason for not using GenerateCheckNonFunctionOrLoaded here.

[Christian Plesner Hansen, 2009/04/24 08:11:22]

Oh, good point.

-  __ ldr(r0, FieldMemOperand(r1, HeapObject::kMapOffset));
-  __ ldrb(r0, FieldMemOperand(r0, Map::kInstanceTypeOffset));
-  __ cmp(r0, Operand(JS_FUNCTION_TYPE));
-  __ b(ne, miss);
-
   // Check that the function has been loaded.
-  __ ldr(r0, FieldMemOperand(r1, JSFunction::kSharedFunctionInfoOffset));
-  __ ldr(r0, FieldMemOperand(r0, SharedFunctionInfo::kLazyLoadDataOffset));
-  __ cmp(r0, Operand(Factory::undefined_value()));
+  __ ldr(r0, FieldMemOperand(r1, JSObject::kMapOffset));
+  __ ldrb(r0, FieldMemOperand(r0, Map::kBitField2Offset));
+  __ tst(r0, Operand(1 << Map::kNeedsLoading));
   __ b(ne, miss);
 
   // Patch the receiver with the global proxy if necessary.
@@ -470,7 +457,7 @@ void LoadIC::GenerateNormal(MacroAssembler* masm) {
 
   __ bind(&probe);
   GenerateDictionaryLoad(masm, &miss, r1, r0);
-  GenerateCheckNonFunctionOrLoaded(masm, &miss, r0, r1);
+  GenerateCheckNonObjectOrLoaded(masm, &miss, r0, r1);
   __ Ret();
 
   // Global object access: Check access rights.