ARM: Fix a bug in the lithium arguments support...

src/arm/lithium-codegen-arm.cc

 // Copyright 2010 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 1575 matching lines @@
   Abort("DoLoadElements unimplemented.");
 }
 
 
 void LCodeGen::DoAccessArgumentsAt(LAccessArgumentsAt* instr) {
   Register arguments = ToRegister(instr->arguments());
   Register length = ToRegister(instr->length());
   Operand index = ToOperand(instr->index());
   Register result = ToRegister(instr->result());
 
-  __ sub(length, length, index);
-  DeoptimizeIf(hi, instr->environment());
+  // Bailout index is not a valid argument index. Use unsigned check to get
+  // negative check for free.
+  __ sub(length, length, index, SetCC);
+  DeoptimizeIf(ls, instr->environment());
 
   // There are two words between the frame pointer and the last argument.
   // Subtracting from length accounts for one of them add one more.
   __ add(length, length, Operand(1));
   __ ldr(result, MemOperand(arguments, length, LSL, kPointerSizeLog2));
 }
 
 
 void LCodeGen::DoLoadKeyedFastElement(LLoadKeyedFastElement* instr) {
   Abort("DoLoadKeyedFastElement unimplemented.");
@@ skipping 802 matching lines @@
 
 
 void LCodeGen::DoOsrEntry(LOsrEntry* instr) {
   Abort("DoOsrEntry unimplemented.");
 }
 
 
 #undef __
 
 } }  // namespace v8::internal