Implement IC for storing to dictionary case objects....

src/ia32/ic-ia32.cc

Index: src/ia32/ic-ia32.cc
===================================================================
--- src/ia32/ic-ia32.cc	(revision 4975)
+++ src/ia32/ic-ia32.cc	(working copy)
@@ -61,11 +61,11 @@
 
 // Generated code falls through if the receiver is a regular non-global
 // JS object with slow properties and no interceptors.
-static void GenerateDictionaryLoadReceiverCheck(MacroAssembler* masm,
-                                                Register receiver,
-                                                Register r0,
-                                                Register r1,
-                                                Label* miss) {
+static void GenerateStringDictionaryReceiverCheck(MacroAssembler* masm,
+                                                  Register receiver,
+                                                  Register r0,
+                                                  Register r1,
+                                                  Label* miss) {
   // Register usage:
   //   receiver: holds the receiver on entry and is unchanged.
   //   r0: used to hold receiver instance type.
@@ -98,36 +98,17 @@
 }
 
 
-// Helper function used to load a property from a dictionary backing storage.
-// This function may return false negatives, so miss_label
-// must always call a backup property load that is complete.
-// This function is safe to call if name is not a symbol, and will jump to
-// the miss_label in that case.
-// The generated code assumes that the receiver has slow properties,
-// is not a global object and does not have interceptors.
-static void GenerateDictionaryLoad(MacroAssembler* masm,
-                                   Label* miss_label,
-                                   Register elements,
-                                   Register name,
-                                   Register r0,
-                                   Register r1,
-                                   Register result) {
-  // Register use:
-  //
-  // elements - holds the property dictionary on entry and is unchanged.
-  //
-  // name - holds the name of the property on entry and is unchanged.
-  //
-  // Scratch registers:
-  //
-  // r0   - used for the index into the property dictionary
-  //
-  // r1   - used to hold the capacity of the property dictionary.
-  //
-  // result - holds the result on exit.
-
-  Label done;
-
+// Probe the string dictionary in the |elements| register. Jump to the
+// |done| label if a property with the given name is found leaving the
+// index into the dictionary in |r0|. Jump to the |miss| label
+// otherwise.
+static void GenerateStringDictionaryProbes(MacroAssembler* masm,
+                                           Label* miss,
+                                           Label* done,
+                                           Register elements,
+                                           Register name,
+                                           Register r0,
+                                           Register r1) {
   // Compute the capacity mask.
   const int kCapacityOffset =
       StringDictionary::kHeaderSize +
@@ -160,14 +141,61 @@
     __ cmp(name, Operand(elements, r0, times_4,
                          kElementsStartOffset - kHeapObjectTag));
     if (i != kProbes - 1) {
-      __ j(equal, &done, taken);
+      __ j(equal, done, taken);
     } else {
-      __ j(not_equal, miss_label, not_taken);
+      __ j(not_equal, miss, not_taken);
     }
   }
+}
 
-  // Check that the value is a normal property.
+
+
+// Helper function used to load a property from a dictionary backing
+// storage. This function may fail to load a property even though it is
+// in the dictionary, so code at miss_label must always call a backup
+// property load that is complete. This function is safe to call if
+// name is not a symbol, and will jump to the miss_label in that
+// case. The generated code assumes that the receiver has slow
+// properties, is not a global object and does not have interceptors.
+static void GenerateDictionaryLoad(MacroAssembler* masm,
+                                   Label* miss_label,
+                                   Register elements,
+                                   Register name,
+                                   Register r0,
+                                   Register r1,
+                                   Register result) {
+  // Register use:
+  //
+  // elements - holds the property dictionary on entry and is unchanged.
+  //
+  // name - holds the name of the property on entry and is unchanged.
+  //
+  // Scratch registers:
+  //
+  // r0   - used for the index into the property dictionary
+  //
+  // r1   - used to hold the capacity of the property dictionary.
+  //
+  // result - holds the result on exit.
+
+  Label done;
+
+  // Probe the dictionary.
+  GenerateStringDictionaryProbes(masm,
+                                 miss_label,
+                                 &done,
+                                 elements,
+                                 name,
+                                 r0,
+                                 r1);
+
+  // If probing finds an entry in the dictionary, r0 contains the
+  // index into the dictionary. Check that the value is a normal
+  // property.
   __ bind(&done);
+  const int kElementsStartOffset =
+      StringDictionary::kHeaderSize +
+      StringDictionary::kElementsStartIndex * kPointerSize;
   const int kDetailsOffset = kElementsStartOffset + 2 * kPointerSize;
   __ test(Operand(elements, r0, times_4, kDetailsOffset - kHeapObjectTag),
           Immediate(PropertyDetails::TypeField::mask() << kSmiTagSize));
@@ -179,6 +207,69 @@
 }
 
 
+// Helper function used to store a property to a dictionary backing
+// storage. This function may fail to store a property eventhough it
+// is in the dictionary, so code at miss_label must always call a
+// backup property store that is complete. This function is safe to
+// call if name is not a symbol, and will jump to the miss_label in
+// that case. The generated code assumes that the receiver has slow
+// properties, is not a global object and does not have interceptors.
+static void GenerateDictionaryStore(MacroAssembler* masm,
+                                    Label* miss_label,
+                                    Register elements,
+                                    Register name,
+                                    Register value,
+                                    Register r0,
+                                    Register r1) {
+  // Register use:
+  //
+  // elements - holds the property dictionary on entry and is clobbered.
+  //
+  // name - holds the name of the property on entry and is unchanged.
+  //
+  // value - holds the value to store and is unchanged.
+  //
+  // r0 - used for index into the property dictionary and is clobbered.
+  //
+  // r1 - used to hold the capacity of the property dictionary and is clobbered.
+  Label done;
+
+
+  // Probe the dictionary.
+  GenerateStringDictionaryProbes(masm,
+                                 miss_label,
+                                 &done,
+                                 elements,
+                                 name,
+                                 r0,
+                                 r1);
+
+  // If probing finds an entry in the dictionary, r0 contains the
+  // index into the dictionary. Check that the value is a normal
+  // property that is not read only.
+  __ bind(&done);
+  const int kElementsStartOffset =
+      StringDictionary::kHeaderSize +
+      StringDictionary::kElementsStartIndex * kPointerSize;
+  const int kDetailsOffset = kElementsStartOffset + 2 * kPointerSize;
+  const int kTypeAndReadOnlyMask
+      = (PropertyDetails::TypeField::mask() |
+         PropertyDetails::AttributesField::encode(READ_ONLY)) << kSmiTagSize;
+  __ test(Operand(elements, r0, times_4, kDetailsOffset - kHeapObjectTag),
+          Immediate(kTypeAndReadOnlyMask));
+  __ j(not_zero, miss_label, not_taken);
+
+  // Store the value at the masked, scaled index.
+  const int kValueOffset = kElementsStartOffset + kPointerSize;
+  __ lea(r0, Operand(elements, r0, times_4, kValueOffset - kHeapObjectTag));
+  __ mov(Operand(r0, 0), value);
+
+  // Update write barrier. Make sure not to clobber the value.
+  __ mov(r1, value);
+  __ RecordWrite(elements, r0, r1);
+}
+
+
 static void GenerateNumberDictionaryLoad(MacroAssembler* masm,
                                          Label* miss,
                                          Register elements,
@@ -1238,7 +1329,7 @@
   // Get the receiver of the function from the stack; 1 ~ return address.
   __ mov(edx, Operand(esp, (argc + 1) * kPointerSize));
 
-  GenerateDictionaryLoadReceiverCheck(masm, edx, eax, ebx, &miss);
+  GenerateStringDictionaryReceiverCheck(masm, edx, eax, ebx, &miss);
 
   // eax: elements
   // Search the dictionary placing the result in edi.
@@ -1517,7 +1608,7 @@
   // -----------------------------------
   Label miss;
 
-  GenerateDictionaryLoadReceiverCheck(masm, eax, edx, ebx, &miss);
+  GenerateStringDictionaryReceiverCheck(masm, eax, edx, ebx, &miss);
 
   // edx: elements
   // Search the dictionary placing the result in eax.
@@ -1775,6 +1866,36 @@
 }
 
 
+void StoreIC::GenerateNormal(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- eax    : value
+  //  -- ecx    : name
+  //  -- edx    : receiver
+  //  -- esp[0] : return address
+  // -----------------------------------
+
+  Label miss, restore_miss;
+
+  GenerateStringDictionaryReceiverCheck(masm, edx, ebx, edi, &miss);
+
+  // A lot of registers are needed for storing to slow case
+  // objects. Push and restore receiver but rely on
+  // GenerateDictionaryStore preserving the value and name.
+  __ push(edx);
+  GenerateDictionaryStore(masm, &restore_miss, ebx, ecx, eax, edx, edi);
+  __ Drop(1);
+  __ IncrementCounter(&Counters::store_normal_hit, 1);
+  __ ret(0);
+
+  __ bind(&restore_miss);
+  __ pop(edx);
+
+  __ bind(&miss);
+  __ IncrementCounter(&Counters::store_normal_miss, 1);
+  GenerateMiss(masm);
+}
+
+
 // Defined in ic.cc.
 Object* KeyedStoreIC_Miss(Arguments args);