KeyedLoadIC should have same register spec as LoadIC.

src/arm64/ic-arm64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/arm64/assembler-arm64.h"
 #include "src/code-stubs.h"
@@ skipping 391 matching lines @@
          backing_store,
          FixedArray::kHeaderSize - kHeapObjectTag);
   __ SmiUntag(scratch, key);
   return MemOperand(backing_store, scratch, LSL, kPointerSizeLog2);
 }
 
 
 void LoadIC::GenerateMegamorphic(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- x2    : name
   //  -- lr    : return address

[Jakob Kummerow, 2014/06/30 14:12:45]

another comment that can be trimmed to "The return address is in lr.", at least
if you use named registers below, possibly instead of the ASSERTs.

[mvstanton, 2014/06/30 14:59:00]

Done.

-  //  -- x0    : receiver
+  //  -- x1    : receiver
   // -----------------------------------
-  ASSERT(x0.is(ReceiverRegister()));
+  ASSERT(x1.is(ReceiverRegister()));
   ASSERT(x2.is(NameRegister()));
 
   // Probe the stub cache.
   Code::Flags flags = Code::ComputeHandlerFlags(Code::LOAD_IC);
   masm->isolate()->stub_cache()->GenerateProbe(
-      masm, flags, x0, x2, x3, x4, x5, x6);
+      masm, flags, x1, x2, x3, x4, x5, x6);
 
   // Cache miss: Jump to runtime.
   GenerateMiss(masm);
 }
 
 
 void LoadIC::GenerateNormal(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- x2    : name
   //  -- lr    : return address
-  //  -- x0    : receiver
+  //  -- x1    : receiver
   // -----------------------------------
-  ASSERT(x0.is(ReceiverRegister()));
+  ASSERT(x1.is(ReceiverRegister()));
   ASSERT(x2.is(NameRegister()));
   Label miss, slow;
 
-  GenerateNameDictionaryReceiverCheck(masm, x0, x1, x3, x4, &miss);
+  GenerateNameDictionaryReceiverCheck(masm, x1, x0, x3, x4, &miss);
 
-  // x1 now holds the property dictionary.
-  GenerateDictionaryLoad(masm, &slow, x1, x2, x0, x3, x4);
+  // x0 now holds the property dictionary.
+  GenerateDictionaryLoad(masm, &slow, x0, x2, x0, x3, x4);
   __ Ret();
 
   // Dictionary load failed, go slow (but don't miss).
   __ Bind(&slow);
   GenerateRuntimeGetProperty(masm);
 
   // Cache miss: Jump to runtime.
   __ Bind(&miss);
   GenerateMiss(masm);
 }
@@ skipping 15 matching lines @@
 
 
 void LoadIC::GenerateRuntimeGetProperty(MacroAssembler* masm) {
   // The return address is on the stack.
   __ Push(ReceiverRegister(), NameRegister());
   __ TailCallRuntime(Runtime::kGetProperty, 2, 1);
 }
 
 
 void KeyedLoadIC::GenerateSloppyArguments(MacroAssembler* masm) {
-  // ---------- S t a t e --------------
-  //  -- lr     : return address
-  //  -- x0     : key
-  //  -- x1     : receiver
-  // -----------------------------------
+  // The return address is on the stack.
   Register result = x0;
   Register receiver = ReceiverRegister();
   Register key = NameRegister();
   ASSERT(receiver.is(x1));
-  ASSERT(key.is(x0));
+  ASSERT(key.is(x2));
 
   Label miss, unmapped;
 
-  Register map_scratch = x2;
+  Register map_scratch = x0;
   MemOperand mapped_location = GenerateMappedArgumentsLookup(
       masm, receiver, key, map_scratch, x3, x4, &unmapped, &miss);
   __ Ldr(result, mapped_location);
   __ Ret();
 
   __ Bind(&unmapped);
   // Parameter map is left in map_scratch when a jump on unmapped is done.
   MemOperand unmapped_location =
       GenerateUnmappedArgumentsLookup(masm, key, map_scratch, x3, &miss);
-  __ Ldr(x2, unmapped_location);
-  __ JumpIfRoot(x2, Heap::kTheHoleValueRootIndex, &miss);
-  // Move the result in x0. x0 must be preserved on miss.
-  __ Mov(result, x2);
+  __ Ldr(x0, unmapped_location);

[Jakob Kummerow, 2014/06/30 14:12:45]

I'd s/x0/result/ here (and in the next line)

[mvstanton, 2014/06/30 14:59:00]

Done.

+  __ JumpIfRoot(x0, Heap::kTheHoleValueRootIndex, &miss);
   __ Ret();
 
   __ Bind(&miss);
   GenerateMiss(masm);
 }
 
 
 void KeyedStoreIC::GenerateSloppyArguments(MacroAssembler* masm) {
   ASM_LOCATION("KeyedStoreIC::GenerateSloppyArguments");
   // ---------- S t a t e --------------
@@ skipping 55 matching lines @@
 
   // Perform tail call to the entry.
   ExternalReference ref =
       ExternalReference(IC_Utility(kKeyedLoadIC_Miss), isolate);
 
   __ TailCallExternalReference(ref, 2, 1);
 }
 
 
 // IC register specifications
-const Register LoadIC::ReceiverRegister() { return x0; }
+const Register LoadIC::ReceiverRegister() { return x1; }
 const Register LoadIC::NameRegister() { return x2; }
-const Register KeyedLoadIC::ReceiverRegister() { return x1; }
-const Register KeyedLoadIC::NameRegister() { return x0; }
 
 
 void KeyedLoadIC::GenerateRuntimeGetProperty(MacroAssembler* masm) {
   // The return address is on the stack.
   __ Push(ReceiverRegister(), NameRegister());
   __ TailCallRuntime(Runtime::kKeyedGetProperty, 2, 1);
 }
 
 
 static void GenerateKeyedLoadWithSmiKey(MacroAssembler* masm,
@@ skipping 153 matching lines @@
   GenerateGlobalInstanceTypeCheck(masm, scratch1, slow);
   // Load the property.
   GenerateDictionaryLoad(masm, slow, scratch2, key, result, scratch1, scratch3);
   __ IncrementCounter(isolate->counters()->keyed_load_generic_symbol(),
                       1, scratch1, scratch2);
   __ Ret();
 }
 
 
 void KeyedLoadIC::GenerateGeneric(MacroAssembler* masm) {
-  // ---------- S t a t e --------------
-  //  -- lr     : return address
-  //  -- x0     : key
-  //  -- x1     : receiver
-  // -----------------------------------
+  // The return address is on the stack.
   Label slow, check_name, index_smi, index_name;
 
   Register key = NameRegister();
   Register receiver = ReceiverRegister();
-  ASSERT(key.is(x0));
+  ASSERT(key.is(x2));
   ASSERT(receiver.is(x1));
 
   __ JumpIfNotSmi(key, &check_name);
   __ Bind(&index_smi);
   // Now the key is known to be a smi. This place is also jumped to from below
   // where a numeric string is converted to a smi.
-  GenerateKeyedLoadWithSmiKey(masm, key, receiver, x2, x3, x4, x5, x6, &slow);
+  GenerateKeyedLoadWithSmiKey(masm, key, receiver, x7, x3, x4, x5, x6, &slow);
 
-  // Slow case, key and receiver still in x0 and x1.
+  // Slow case

[Jakob Kummerow, 2014/06/30 14:12:45]

nit: trailing full stop please.

[mvstanton, 2014/06/30 14:59:00]

Done.

   __ Bind(&slow);
   __ IncrementCounter(
-      masm->isolate()->counters()->keyed_load_generic_slow(), 1, x2, x3);
+      masm->isolate()->counters()->keyed_load_generic_slow(), 1, x4, x3);
   GenerateRuntimeGetProperty(masm);
 
   __ Bind(&check_name);
-  GenerateKeyNameCheck(masm, key, x2, x3, &index_name, &slow);
+  GenerateKeyNameCheck(masm, key, x0, x3, &index_name, &slow);
 
-  GenerateKeyedLoadWithNameKey(masm, key, receiver, x2, x3, x4, x5, x6, &slow);
+  GenerateKeyedLoadWithNameKey(masm, key, receiver, x7, x3, x4, x5, x6, &slow);
 
   __ Bind(&index_name);
   __ IndexFromHash(x3, key);
   // Now jump to the place where smi keys are handled.
   __ B(&index_smi);
 }
 
 
 void KeyedLoadIC::GenerateString(MacroAssembler* masm) {

[Jakob Kummerow, 2014/06/30 14:12:45]

Wohoo! Register refactoring nirvana -- nothing to do here :-)

[mvstanton, 2014/06/30 14:59:00]

:D

   // Return address is on the stack.
   Label miss;
 
   Register receiver = ReceiverRegister();
   Register index = NameRegister();
   Register result = x0;
   Register scratch = x3;
   ASSERT(!scratch.is(receiver) && !scratch.is(index));
 
   StringCharAtGenerator char_at_generator(receiver,
@@ skipping 14 matching lines @@
   GenerateMiss(masm);
 }
 
 
 void KeyedLoadIC::GenerateIndexedInterceptor(MacroAssembler* masm) {
   // Return address is on the stack.
   Label slow;
 
   Register receiver = ReceiverRegister();
   Register key = NameRegister();
-  Register scratch1 = x2;
-  Register scratch2 = x3;
+  Register scratch1 = x3;
+  Register scratch2 = x4;
   ASSERT(!scratch1.is(receiver) && !scratch1.is(key));
   ASSERT(!scratch2.is(receiver) && !scratch2.is(key));
 
   // Check that the receiver isn't a smi.
   __ JumpIfSmi(receiver, &slow);
 
   // Check that the key is an array index, that is Uint32.
   __ TestAndBranchIfAnySet(key, kSmiTagMask | kSmiSignMask, &slow);
 
   // Get the map of the receiver.
@@ skipping 532 matching lines @@
     ASSERT(to_patch->Mask(TestBranchMask) == TBNZ);
     // This is JumpIfSmi(smi_reg, branch_imm).
     patcher.tbz(smi_reg, 0, branch_imm);
   }
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM64