Port some GC fixes from the bleeding edge to the 2.3 branch. These are:...

src/arm/ic-arm.cc

 // Copyright 2006-2008 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 1409 matching lines @@
     // it to a HeapNumber.
     Label box_int;
     __ cmp(value, Operand(0xC0000000));
     __ b(mi, &box_int);
     // Tag integer as smi and return it.
     __ mov(r0, Operand(value, LSL, kSmiTagSize));
     __ Ret();
 
     __ bind(&box_int);
     // Allocate a HeapNumber for the result and perform int-to-double
-    // conversion. Use r0 for result as key is not needed any more.
+    // conversion.  Don't touch r0 or r1 as they are needed if allocation
+    // fails.
     __ LoadRoot(r6, Heap::kHeapNumberMapRootIndex);
-    __ AllocateHeapNumber(r0, r3, r4, r6, &slow);
+    __ AllocateHeapNumber(r5, r3, r4, r6, &slow);
+    // Now we can use r0 for the result as key is not needed any more.
+    __ mov(r0, r5);
 
     if (CpuFeatures::IsSupported(VFP3)) {
       CpuFeatures::Scope scope(VFP3);
       __ vmov(s0, value);
       __ vcvt_f64_s32(d0, s0);
       __ sub(r3, r0, Operand(kHeapObjectTag));
       __ vstr(d0, r3, HeapNumber::kValueOffset);
       __ Ret();
     } else {
       WriteInt32ToHeapNumberStub stub(value, r0, r3);
@@ skipping 826 matching lines @@
   GenerateMiss(masm);
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM