PPC/s390: [crankshaft] Fix Smi overflow in {HMaybeGrowElements}.

src/crankshaft/s390/lithium-codegen-s390.cc

 // Copyright 2014 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/crankshaft/s390/lithium-codegen-s390.h"
 
 #include "src/base/bits.h"
 #include "src/builtins/builtins-constructor.h"
 #include "src/code-factory.h"
@@ skipping 4265 matching lines @@
       __ LoadP(result, ToMemOperand(instr->object()));
     }
 
     LOperand* key = instr->key();
     if (key->IsConstantOperand()) {
       LConstantOperand* constant_key = LConstantOperand::cast(key);
       int32_t int_key = ToInteger32(constant_key);
       if (Smi::IsValid(int_key)) {
         __ LoadSmiLiteral(r5, Smi::FromInt(int_key));
       } else {
-        // We should never get here at runtime because there is a smi check on
-        // the key before this point.
-        __ stop("expected smi");
+        Abort(kArrayIndexConstantValueTooBig);
       }
     } else {
+      Label is_smi;
+#if V8_TARGET_ARCH_S390X
       __ SmiTag(r5, ToRegister(key));
+#else
+      // Deopt if the key is outside Smi range. The stub expects Smi and would
+      // bump the elements into dictionary mode (and trigger a deopt) anyways.
+      __ Add32(r5, ToRegister(key), ToRegister(key));
+      __ b(nooverflow, &is_smi);
+      __ PopSafepointRegisters();
+      DeoptimizeIf(al, instr, DeoptimizeReason::kOverflow, cr0);
+      __ bind(&is_smi);
+#endif
     }
 
     GrowArrayElementsStub stub(isolate(), instr->hydrogen()->kind());
     __ CallStub(&stub);
     RecordSafepointWithLazyDeopt(
         instr, RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS);
     __ StoreToSafepointRegisterSlot(result, result);
   }
 
   // Deopt on smi, which means the elements array changed to dictionary mode.
@@ skipping 1297 matching lines @@
   __ LoadP(result,
            FieldMemOperand(scratch, FixedArray::kHeaderSize - kPointerSize));
   __ bind(deferred->exit());
   __ bind(&done);
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8