Fixed two register allocator bugs (off-by-one error/failure propagation).

src/x64/lithium-x64.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 665 matching lines @@
 LInstruction* LChunkBuilder::AssignPointerMap(LInstruction* instr) {
   ASSERT(!instr->HasPointerMap());
   instr->set_pointer_map(new(zone()) LPointerMap(position_, zone()));
   return instr;
 }
 
 
 LUnallocated* LChunkBuilder::TempRegister() {
   LUnallocated* operand =
       new(zone()) LUnallocated(LUnallocated::MUST_HAVE_REGISTER);
-  operand->set_virtual_register(allocator_->GetVirtualRegister());
-  if (!allocator_->AllocationOk()) Abort("Not enough virtual registers.");
+  int vreg = allocator_->GetVirtualRegister();
+  if (!allocator_->AllocationOk()) {
+    Abort("Out of virtual registers while trying to allocate temp register.");
+    return NULL;
+  }
+  operand->set_virtual_register(vreg);
   return operand;
 }
 
 
 LOperand* LChunkBuilder::FixedTemp(Register reg) {
   LUnallocated* operand = ToUnallocated(reg);
   ASSERT(operand->HasFixedPolicy());
   return operand;
 }
 
@@ skipping 1748 matching lines @@
 LInstruction* LChunkBuilder::DoLoadFieldByIndex(HLoadFieldByIndex* instr) {
   LOperand* object = UseRegister(instr->object());
   LOperand* index = UseTempRegister(instr->index());
   return DefineSameAsFirst(new(zone()) LLoadFieldByIndex(object, index));
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64