ia32: Redefine register usage in LoadIC/KeyedLoadIC to match StoreIC and KeyedStoreIC

src/ia32/ic-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 200 matching lines @@
   __ mov(Operand(r0, 0), value);
 
   // Update write barrier. Make sure not to clobber the value.
   __ mov(r1, value);
   __ RecordWrite(elements, r0, r1, kDontSaveFPRegs);
 }
 
 
 void LoadIC::GenerateArrayLength(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- eax    : receiver
   //  -- ecx    : name
+  //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
-  StubCompiler::GenerateLoadArrayLength(masm, eax, edx, &miss);
+  StubCompiler::GenerateLoadArrayLength(masm, edx, eax, &miss);
   __ bind(&miss);
   StubCompiler::GenerateLoadMiss(masm, Code::LOAD_IC);
 }
 
 
 void LoadIC::GenerateStringLength(MacroAssembler* masm,
                                   bool support_wrappers) {
   // ----------- S t a t e -------------
-  //  -- eax    : receiver
   //  -- ecx    : name
+  //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
-  StubCompiler::GenerateLoadStringLength(masm, eax, edx, ebx, &miss,
+  StubCompiler::GenerateLoadStringLength(masm, edx, eax, ebx, &miss,
                                          support_wrappers);
   __ bind(&miss);
   StubCompiler::GenerateLoadMiss(masm, Code::LOAD_IC);
 }
 
 
 void LoadIC::GenerateFunctionPrototype(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- eax    : receiver
   //  -- ecx    : name
+  //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
-  StubCompiler::GenerateLoadFunctionPrototype(masm, eax, edx, ebx, &miss);
+  StubCompiler::GenerateLoadFunctionPrototype(masm, edx, eax, ebx, &miss);
   __ bind(&miss);
   StubCompiler::GenerateLoadMiss(masm, Code::LOAD_IC);
 }
 
 
 // Checks the receiver for special cases (value type, slow case bits).
 // Falls through for regular JS object.
 static void GenerateKeyedLoadReceiverCheck(MacroAssembler* masm,
                                            Register receiver,
                                            Register map,
@@ skipping 168 matching lines @@
   __ j(greater_equal, slow_case);
   return FieldOperand(backing_store,
                       key,
                       times_half_pointer_size,
                       FixedArray::kHeaderSize);
 }
 
 
 void KeyedLoadIC::GenerateGeneric(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- eax    : key
+  //  -- ecx    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label slow, check_string, index_smi, index_string, property_array_property;
   Label probe_dictionary, check_number_dictionary;
 
   // Check that the key is a smi.
-  __ JumpIfNotSmi(eax, &check_string);
+  __ JumpIfNotSmi(ecx, &check_string);
   __ bind(&index_smi);
   // Now the key is known to be a smi. This place is also jumped to from
   // where a numeric string is converted to a smi.
 
   GenerateKeyedLoadReceiverCheck(
-      masm, edx, ecx, Map::kHasIndexedInterceptor, &slow);
+      masm, edx, eax, Map::kHasIndexedInterceptor, &slow);
 
   // Check the receiver's map to see if it has fast elements.
-  __ CheckFastElements(ecx, &check_number_dictionary);
+  __ CheckFastElements(eax, &check_number_dictionary);
 
-  GenerateFastArrayLoad(masm,
-                        edx,
-                        eax,
-                        ecx,
-                        eax,
-                        NULL,
-                        &slow);
+  GenerateFastArrayLoad(masm, edx, ecx, eax, eax, NULL, &slow);
   Isolate* isolate = masm->isolate();
   Counters* counters = isolate->counters();
   __ IncrementCounter(counters->keyed_load_generic_smi(), 1);
   __ ret(0);
+
   __ bind(&check_number_dictionary);
-  __ mov(ebx, eax);
+  __ mov(ebx, ecx);
   __ SmiUntag(ebx);
-  __ mov(ecx, FieldOperand(edx, JSObject::kElementsOffset));
+  __ mov(eax, FieldOperand(edx, JSObject::kElementsOffset));
 
   // Check whether the elements is a number dictionary.
   // edx: receiver
   // ebx: untagged index
-  // eax: key
-  // ecx: elements
-  __ CheckMap(ecx,
+  // ecx: key
+  // eax: elements
+  __ CheckMap(eax,
               isolate->factory()->hash_table_map(),
               &slow,
               DONT_DO_SMI_CHECK);
   Label slow_pop_receiver;
   // Push receiver on the stack to free up a register for the dictionary
   // probing.
   __ push(edx);
-  __ LoadFromNumberDictionary(&slow_pop_receiver,
-                              ecx,
-                              eax,
-                              ebx,
-                              edx,
-                              edi,
-                              eax);
+  __ LoadFromNumberDictionary(&slow_pop_receiver, eax, ecx, ebx, edx, edi, eax);
   // Pop receiver before returning.
   __ pop(edx);
   __ ret(0);
 
   __ bind(&slow_pop_receiver);
   // Pop the receiver from the stack and jump to runtime.
   __ pop(edx);
 
   __ bind(&slow);
   // Slow case: jump to runtime.
   // edx: receiver
-  // eax: key
+  // ecx: key
   __ IncrementCounter(counters->keyed_load_generic_slow(), 1);
   GenerateRuntimeGetProperty(masm);
 
   __ bind(&check_string);
-  GenerateKeyStringCheck(masm, eax, ecx, ebx, &index_string, &slow);
+  GenerateKeyStringCheck(masm, ecx, eax, ebx, &index_string, &slow);
 
   GenerateKeyedLoadReceiverCheck(
-      masm, edx, ecx, Map::kHasNamedInterceptor, &slow);
+      masm, edx, eax, Map::kHasNamedInterceptor, &slow);
 
   // If the receiver is a fast-case object, check the keyed lookup
   // cache. Otherwise probe the dictionary.
   __ mov(ebx, FieldOperand(edx, JSObject::kPropertiesOffset));
   __ cmp(FieldOperand(ebx, HeapObject::kMapOffset),
          Immediate(isolate->factory()->hash_table_map()));
   __ j(equal, &probe_dictionary);
 
-  // Load the map of the receiver, compute the keyed lookup cache hash
+  // The receiver's map is still in eax, compute the keyed lookup cache hash
   // based on 32 bits of the map pointer and the string hash.
-  __ mov(ebx, FieldOperand(edx, HeapObject::kMapOffset));
-  __ mov(ecx, ebx);
-  __ shr(ecx, KeyedLookupCache::kMapHashShift);
-  __ mov(edi, FieldOperand(eax, String::kHashFieldOffset));
+  if (FLAG_debug_code) {
+    __ cmp(eax, FieldOperand(edx, HeapObject::kMapOffset));
+    __ Check(equal, "Map is no longer in eax.");
+  }
+  __ mov(ebx, eax);  // Keep the map around for later.
+  __ shr(eax, KeyedLookupCache::kMapHashShift);
+  __ mov(edi, FieldOperand(ecx, String::kHashFieldOffset));
   __ shr(edi, String::kHashShift);
-  __ xor_(ecx, edi);
-  __ and_(ecx, KeyedLookupCache::kCapacityMask & KeyedLookupCache::kHashMask);
+  __ xor_(eax, edi);
+  __ and_(eax, KeyedLookupCache::kCapacityMask & KeyedLookupCache::kHashMask);
 
   // Load the key (consisting of map and symbol) from the cache and
   // check for match.
   Label load_in_object_property;
   static const int kEntriesPerBucket = KeyedLookupCache::kEntriesPerBucket;
   Label hit_on_nth_entry[kEntriesPerBucket];
   ExternalReference cache_keys =
       ExternalReference::keyed_lookup_cache_keys(masm->isolate());
 
   for (int i = 0; i < kEntriesPerBucket - 1; i++) {
     Label try_next_entry;
-    __ mov(edi, ecx);
+    __ mov(edi, eax);
     __ shl(edi, kPointerSizeLog2 + 1);
     if (i != 0) {
       __ add(edi, Immediate(kPointerSize * i * 2));
     }
     __ cmp(ebx, Operand::StaticArray(edi, times_1, cache_keys));
     __ j(not_equal, &try_next_entry);
     __ add(edi, Immediate(kPointerSize));
-    __ cmp(eax, Operand::StaticArray(edi, times_1, cache_keys));
+    __ cmp(ecx, Operand::StaticArray(edi, times_1, cache_keys));
     __ j(equal, &hit_on_nth_entry[i]);
     __ bind(&try_next_entry);
   }
 
-  __ lea(edi, Operand(ecx, 1));
+  __ lea(edi, Operand(eax, 1));
   __ shl(edi, kPointerSizeLog2 + 1);
   __ add(edi, Immediate(kPointerSize * (kEntriesPerBucket - 1) * 2));
   __ cmp(ebx, Operand::StaticArray(edi, times_1, cache_keys));
   __ j(not_equal, &slow);
   __ add(edi, Immediate(kPointerSize));
-  __ cmp(eax, Operand::StaticArray(edi, times_1, cache_keys));
+  __ cmp(ecx, Operand::StaticArray(edi, times_1, cache_keys));
   __ j(not_equal, &slow);
 
   // Get field offset.
   // edx     : receiver
   // ebx     : receiver's map
-  // eax     : key
-  // ecx     : lookup cache index
+  // ecx     : key
+  // eax     : lookup cache index
   ExternalReference cache_field_offsets =
       ExternalReference::keyed_lookup_cache_field_offsets(masm->isolate());
 
   // Hit on nth entry.
   for (int i = kEntriesPerBucket - 1; i >= 0; i--) {
     __ bind(&hit_on_nth_entry[i]);
     if (i != 0) {
-      __ add(ecx, Immediate(i));
+      __ add(eax, Immediate(i));
     }
     __ mov(edi,
-           Operand::StaticArray(ecx, times_pointer_size, cache_field_offsets));
-    __ movzx_b(ecx, FieldOperand(ebx, Map::kInObjectPropertiesOffset));
-    __ sub(edi, ecx);
+           Operand::StaticArray(eax, times_pointer_size, cache_field_offsets));
+    __ movzx_b(eax, FieldOperand(ebx, Map::kInObjectPropertiesOffset));
+    __ sub(edi, eax);
     __ j(above_equal, &property_array_property);
     if (i != 0) {
       __ jmp(&load_in_object_property);
     }
   }
 
   // Load in-object property.
   __ bind(&load_in_object_property);
-  __ movzx_b(ecx, FieldOperand(ebx, Map::kInstanceSizeOffset));
-  __ add(ecx, edi);
-  __ mov(eax, FieldOperand(edx, ecx, times_pointer_size, 0));
+  __ movzx_b(eax, FieldOperand(ebx, Map::kInstanceSizeOffset));
+  __ add(eax, edi);
+  __ mov(eax, FieldOperand(edx, eax, times_pointer_size, 0));
   __ IncrementCounter(counters->keyed_load_generic_lookup_cache(), 1);
   __ ret(0);
 
   // Load property array property.
   __ bind(&property_array_property);
   __ mov(eax, FieldOperand(edx, JSObject::kPropertiesOffset));
   __ mov(eax, FieldOperand(eax, edi, times_pointer_size,
                            FixedArray::kHeaderSize));
   __ IncrementCounter(counters->keyed_load_generic_lookup_cache(), 1);
   __ ret(0);
 
   // Do a quick inline probe of the receiver's dictionary, if it
   // exists.
   __ bind(&probe_dictionary);
 
-  __ mov(ecx, FieldOperand(edx, JSObject::kMapOffset));
-  __ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
-  GenerateGlobalInstanceTypeCheck(masm, ecx, &slow);
+  __ mov(eax, FieldOperand(edx, JSObject::kMapOffset));
+  __ movzx_b(eax, FieldOperand(eax, Map::kInstanceTypeOffset));
+  GenerateGlobalInstanceTypeCheck(masm, eax, &slow);
 
-  GenerateDictionaryLoad(masm, &slow, ebx, eax, ecx, edi, eax);
+  GenerateDictionaryLoad(masm, &slow, ebx, ecx, eax, edi, eax);
   __ IncrementCounter(counters->keyed_load_generic_symbol(), 1);
   __ ret(0);
 
   __ bind(&index_string);
-  __ IndexFromHash(ebx, eax);
+  __ IndexFromHash(ebx, ecx);
   // Now jump to the place where smi keys are handled.
   __ jmp(&index_smi);
 }
 
 
 void KeyedLoadIC::GenerateString(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- eax    : key (index)
+  //  -- ecx    : key (index)
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
   Register receiver = edx;
-  Register index = eax;
-  Register scratch = ecx;
+  Register index = ecx;
+  Register scratch = ebx;
   Register result = eax;
 
   StringCharAtGenerator char_at_generator(receiver,
                                           index,
                                           scratch,
                                           result,
                                           &miss,  // When not a string.
                                           &miss,  // When not a number.
                                           &miss,  // When index out of range.
                                           STRING_INDEX_IS_ARRAY_INDEX);
   char_at_generator.GenerateFast(masm);
   __ ret(0);
 
   StubRuntimeCallHelper call_helper;
   char_at_generator.GenerateSlow(masm, call_helper);
 
   __ bind(&miss);
   GenerateMiss(masm, false);
 }
 
 
 void KeyedLoadIC::GenerateIndexedInterceptor(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- eax    : key
+  //  -- ecx    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label slow;
 
   // Check that the receiver isn't a smi.
   __ JumpIfSmi(edx, &slow);
 
   // Check that the key is an array index, that is Uint32.
-  __ test(eax, Immediate(kSmiTagMask | kSmiSignMask));
+  __ test(ecx, Immediate(kSmiTagMask | kSmiSignMask));
   __ j(not_zero, &slow);
 
   // Get the map of the receiver.
-  __ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
+  __ mov(eax, FieldOperand(edx, HeapObject::kMapOffset));
 
   // Check that it has indexed interceptor and access checks
   // are not enabled for this object.
-  __ movzx_b(ecx, FieldOperand(ecx, Map::kBitFieldOffset));
-  __ and_(ecx, Immediate(kSlowCaseBitFieldMask));
-  __ cmp(ecx, Immediate(1 << Map::kHasIndexedInterceptor));
+  __ movzx_b(eax, FieldOperand(eax, Map::kBitFieldOffset));
+  __ and_(eax, Immediate(kSlowCaseBitFieldMask));
+  __ cmp(eax, Immediate(1 << Map::kHasIndexedInterceptor));
   __ j(not_zero, &slow);
 
   // Everything is fine, call runtime.
-  __ pop(ecx);
+  __ pop(eax);
   __ push(edx);  // receiver
-  __ push(eax);  // key
-  __ push(ecx);  // return address
+  __ push(ecx);  // key
+  __ push(eax);  // return address
 
   // Perform tail call to the entry.
   ExternalReference ref =
       ExternalReference(IC_Utility(kKeyedLoadPropertyWithInterceptor),
                         masm->isolate());
   __ TailCallExternalReference(ref, 2, 1);
 
   __ bind(&slow);
   GenerateMiss(masm, false);
 }
 
 
 void KeyedLoadIC::GenerateNonStrictArguments(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- eax    : key
+  //  -- ecx    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label slow, notin;
   Factory* factory = masm->isolate()->factory();
   Operand mapped_location =
-      GenerateMappedArgumentsLookup(masm, edx, eax, ebx, ecx, &notin, &slow);
+      GenerateMappedArgumentsLookup(masm, edx, ecx, ebx, eax, &notin, &slow);
   __ mov(eax, mapped_location);
   __ Ret();
   __ bind(&notin);
   // The unmapped lookup expects that the parameter map is in ebx.
   Operand unmapped_location =
-      GenerateUnmappedArgumentsLookup(masm, eax, ebx, ecx, &slow);
+      GenerateUnmappedArgumentsLookup(masm, ecx, ebx, eax, &slow);
   __ cmp(unmapped_location, factory->the_hole_value());
   __ j(equal, &slow);
   __ mov(eax, unmapped_location);
   __ Ret();
   __ bind(&slow);
   GenerateMiss(masm, false);
 }
 
 
 void KeyedStoreIC::GenerateNonStrictArguments(MacroAssembler* masm) {
@@ skipping 571 matching lines @@
   Condition cond = masm->IsObjectStringType(ecx, eax, eax);
   __ j(NegateCondition(cond), &miss);
   CallICBase::GenerateNormal(masm, argc);
   __ bind(&miss);
   GenerateMiss(masm, argc);
 }
 
 
 void LoadIC::GenerateMegamorphic(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- eax    : receiver
   //  -- ecx    : name
+  //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
 
   // Probe the stub cache.
   Code::Flags flags = Code::ComputeFlags(Code::LOAD_IC, MONOMORPHIC);
-  Isolate::Current()->stub_cache()->GenerateProbe(masm, flags, eax, ecx, ebx,
-                                                  edx);
+  Isolate::Current()->stub_cache()->GenerateProbe(masm, flags, edx, ecx, ebx,
+                                                  eax);
 
   // Cache miss: Jump to runtime.
   GenerateMiss(masm);
 }
 
 
 void LoadIC::GenerateNormal(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- eax    : receiver
   //  -- ecx    : name
+  //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label miss;
 
-  GenerateStringDictionaryReceiverCheck(masm, eax, edx, ebx, &miss);
+  GenerateStringDictionaryReceiverCheck(masm, edx, eax, ebx, &miss);
 
-  // edx: elements
+  // eax: elements
   // Search the dictionary placing the result in eax.
-  GenerateDictionaryLoad(masm, &miss, edx, ecx, edi, ebx, eax);
+  GenerateDictionaryLoad(masm, &miss, eax, ecx, edi, ebx, eax);
   __ ret(0);
 
   // Cache miss: Jump to runtime.
   __ bind(&miss);
   GenerateMiss(masm);
 }
 
 
 void LoadIC::GenerateMiss(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- eax    : receiver
   //  -- ecx    : name
+  //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
 
   __ IncrementCounter(masm->isolate()->counters()->load_miss(), 1);
 
   __ pop(ebx);
-  __ push(eax);  // receiver
+  __ push(edx);  // receiver
   __ push(ecx);  // name
   __ push(ebx);  // return address
 
   // Perform tail call to the entry.
   ExternalReference ref =
       ExternalReference(IC_Utility(kLoadIC_Miss), masm->isolate());
   __ TailCallExternalReference(ref, 2, 1);
 }
 
 
 void KeyedLoadIC::GenerateMiss(MacroAssembler* masm, bool force_generic) {
   // ----------- S t a t e -------------
-  //  -- eax    : key
+  //  -- ecx    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
 
   __ IncrementCounter(masm->isolate()->counters()->keyed_load_miss(), 1);
 
   __ pop(ebx);
   __ push(edx);  // receiver
-  __ push(eax);  // name
+  __ push(ecx);  // name
   __ push(ebx);  // return address
 
   // Perform tail call to the entry.
   ExternalReference ref = force_generic
       ? ExternalReference(IC_Utility(kKeyedLoadIC_MissForceGeneric),
                           masm->isolate())
       : ExternalReference(IC_Utility(kKeyedLoadIC_Miss), masm->isolate());
   __ TailCallExternalReference(ref, 2, 1);
 }
 
 
 void KeyedLoadIC::GenerateRuntimeGetProperty(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- eax    : key
+  //  -- ecx    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
 
   __ pop(ebx);
   __ push(edx);  // receiver
-  __ push(eax);  // name
+  __ push(ecx);  // name
   __ push(ebx);  // return address
 
   // Perform tail call to the entry.
   __ TailCallRuntime(Runtime::kKeyedGetProperty, 2, 1);
 }
 
 
 void StoreIC::GenerateMegamorphic(MacroAssembler* masm,
                                   StrictModeFlag strict_mode) {
   // ----------- S t a t e -------------
@@ skipping 358 matching lines @@
   Condition cc = *jmp_address == Assembler::kJncShortOpcode
       ? not_zero
       : zero;
   *jmp_address = static_cast<byte>(Assembler::kJccShortPrefix | cc);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32