Fix hole handling, and ensure smi representation is handled properly

src/x64/lithium-codegen-x64.cc

 // Copyright 2013 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 3629 matching lines @@
   // Just make sure that the input/output registers are the expected ones.
 
   Register exponent = rdx;
   ASSERT(!instr->right()->IsRegister() ||
          ToRegister(instr->right()).is(exponent));
   ASSERT(!instr->right()->IsDoubleRegister() ||
          ToDoubleRegister(instr->right()).is(xmm1));
   ASSERT(ToDoubleRegister(instr->left()).is(xmm2));
   ASSERT(ToDoubleRegister(instr->result()).is(xmm3));
 
-  if (exponent_type.IsTagged()) {
+  if (exponent_type.IsSmi()) {
+    MathPowStub stub(MathPowStub::TAGGED);
+    __ CallStub(&stub);
+  } else if (exponent_type.IsTagged()) {
     Label no_deopt;
     __ JumpIfSmi(exponent, &no_deopt);
     __ CmpObjectType(exponent, HEAP_NUMBER_TYPE, rcx);
     DeoptimizeIf(not_equal, instr->environment());
     __ bind(&no_deopt);
     MathPowStub stub(MathPowStub::TAGGED);
     __ CallStub(&stub);
   } else if (exponent_type.IsInteger32()) {
     MathPowStub stub(MathPowStub::INTEGER);
     __ CallStub(&stub);
@@ skipping 975 matching lines @@
   __ Integer32ToSmi(input, input);
 }
 
 
 void LCodeGen::DoSmiUntag(LSmiUntag* instr) {
   ASSERT(instr->value()->Equals(instr->result()));
   Register input = ToRegister(instr->value());
   if (instr->needs_check()) {
     Condition is_smi = __ CheckSmi(input);
     DeoptimizeIf(NegateCondition(is_smi), instr->environment());
-  } else if (instr->hydrogen()->value()->IsLoadKeyed()) {
-    HLoadKeyed* load = HLoadKeyed::cast(instr->hydrogen()->value());
-    if (load->UsesMustHandleHole()) {
-      Condition cc = masm()->CheckSmi(input);
-      if (load->hole_mode() == ALLOW_RETURN_HOLE) {
-        Label done;
-        __ j(cc, &done);
-        __ xor_(input, input);
-        __ bind(&done);
-      } else {
-        DeoptimizeIf(NegateCondition(cc), instr->environment());
-      }
-    } else {
-      __ AssertSmi(input);
-    }
   } else {
     __ AssertSmi(input);
   }
   __ SmiToInteger32(input, input);
 }
 
 
 void LCodeGen::EmitNumberUntagD(Register input_reg,
                                 XMMRegister result_reg,
                                 bool deoptimize_on_undefined,
@@ skipping 1019 matching lines @@
                                FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64