MIPS: Fix hole handling, and ensure smi representation is handled properly

Port r14807 (c26f44d6)

BUG=

Review URL: https://codereview.chromium.org/15821007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14812 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/mips/lithium-codegen-mips.cc

@@ -3644,7 +3644,10 @@ void LCodeGen::DoPower(LPower* instr) {
   ASSERT(ToDoubleRegister(instr->left()).is(f2));
   ASSERT(ToDoubleRegister(instr->result()).is(f0));
 
-  if (exponent_type.IsTagged()) {
+  if (exponent_type.IsSmi()) {
+    MathPowStub stub(MathPowStub::TAGGED);
+    __ CallStub(&stub);
+  } else if (exponent_type.IsTagged()) {
     Label no_deopt;
     __ JumpIfSmi(a2, &no_deopt);
     __ lw(t3, FieldMemOperand(a2, HeapObject::kMapOffset));
@@ -4648,22 +4651,6 @@ void LCodeGen::DoSmiUntag(LSmiUntag* instr) {
     __ And(scratch, input, Operand(kHeapObjectTag));
     __ SmiUntag(result, input);
     DeoptimizeIf(ne, instr->environment(), scratch, Operand(zero_reg));
-  } else if (instr->hydrogen()->value()->IsLoadKeyed()) {
-    HLoadKeyed* load = HLoadKeyed::cast(instr->hydrogen()->value());
-    if (load->UsesMustHandleHole()) {
-      __ And(scratch, input, Operand(kHeapObjectTag));
-      __ SmiUntag(result, input);
-      if (load->hole_mode() == ALLOW_RETURN_HOLE) {
-        Label done;
-        __ Branch(&done, eq, scratch, Operand(zero_reg));
-        __ li(result, Operand(Smi::FromInt(0)));
-        __ bind(&done);
-      } else {
-        DeoptimizeIf(ne, instr->environment(), scratch, Operand(zero_reg));
-      }
-    } else {
-      __ SmiUntag(result, input);
-    }
   } else {
     __ SmiUntag(result, input);
   }

src/mips/lithium-mips.cc

@@ -714,9 +714,9 @@ LInstruction* LChunkBuilder::DoDeoptimize(HDeoptimize* instr) {
 
 LInstruction* LChunkBuilder::DoShift(Token::Value op,
                                      HBitwiseBinaryOperation* instr) {
-  if (instr->representation().IsTagged()) {
-    ASSERT(instr->left()->representation().IsTagged());
-    ASSERT(instr->right()->representation().IsTagged());
+  if (instr->representation().IsSmiOrTagged()) {
+    ASSERT(instr->left()->representation().IsSmiOrTagged());
+    ASSERT(instr->right()->representation().IsSmiOrTagged());
 
     LOperand* left = UseFixed(instr->left(), a1);
     LOperand* right = UseFixed(instr->right(), a0);
@@ -784,8 +784,8 @@ LInstruction* LChunkBuilder::DoArithmeticT(Token::Value op,
          op == Token::SUB);
   HValue* left = instr->left();
   HValue* right = instr->right();
-  ASSERT(left->representation().IsTagged());
-  ASSERT(right->representation().IsTagged());
+  ASSERT(left->representation().IsSmiOrTagged());
+  ASSERT(right->representation().IsSmiOrTagged());
   LOperand* left_operand = UseFixed(left, a1);
   LOperand* right_operand = UseFixed(right, a0);
   LArithmeticT* result =
@@ -1304,9 +1304,9 @@ LInstruction* LChunkBuilder::DoBitwise(HBitwise* instr) {
     LOperand* right = UseOrConstantAtStart(instr->BetterRightOperand());
     return DefineAsRegister(new(zone()) LBitI(left, right));
   } else {
-    ASSERT(instr->representation().IsTagged());
-    ASSERT(instr->left()->representation().IsTagged());
-    ASSERT(instr->right()->representation().IsTagged());
+    ASSERT(instr->representation().IsSmiOrTagged());
+    ASSERT(instr->left()->representation().IsSmiOrTagged());
+    ASSERT(instr->right()->representation().IsSmiOrTagged());
 
     LOperand* left = UseFixed(instr->left(), a1);
     LOperand* right = UseFixed(instr->right(), a0);
@@ -1377,7 +1377,7 @@ LInstruction* LChunkBuilder::DoMod(HMod* instr) {
     } else {
       return DefineAsRegister(mod);
     }
-  } else if (instr->representation().IsTagged()) {
+  } else if (instr->representation().IsSmiOrTagged()) {
     return DoArithmeticT(Token::MOD, instr);
   } else {
     ASSERT(instr->representation().IsDouble());
@@ -1490,7 +1490,7 @@ LInstruction* LChunkBuilder::DoAdd(HAdd* instr) {
     }
     return DoArithmeticD(Token::ADD, instr);
   } else {
-    ASSERT(instr->representation().IsTagged());
+    ASSERT(instr->representation().IsSmiOrTagged());
     return DoArithmeticT(Token::ADD, instr);
   }
 }
@@ -1762,12 +1762,6 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
   if (from.IsSmi()) {
     if (to.IsTagged()) {
       LOperand* value = UseRegister(instr->value());
-      // For now, always deopt on hole.
-      if (instr->value()->IsLoadKeyed() &&
-          HLoadKeyed::cast(instr->value())->UsesMustHandleHole()) {
-        return AssignEnvironment(
-            DefineSameAsFirst(new(zone()) LCheckSmiAndReturn(value)));
-      }
       return DefineSameAsFirst(new(zone()) LDummyUse(value));
     }
     from = Representation::Tagged();
@@ -1793,13 +1787,6 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
       if (instr->value()->type().IsSmi()) {
         value = UseRegisterAtStart(instr->value());
         res = DefineAsRegister(new(zone()) LSmiUntag(value, false));
-        if (instr->value()->IsLoadKeyed()) {
-          HLoadKeyed* load_keyed = HLoadKeyed::cast(instr->value());
-          if (load_keyed->UsesMustHandleHole() &&
-              load_keyed->hole_mode() == NEVER_RETURN_HOLE) {
-            res = AssignEnvironment(res);
-          }
-        }
       } else {
         value = UseRegister(instr->value());
         LOperand* temp1 = TempRegister();

src/mips/lithium-mips.h

@@ -2069,7 +2069,6 @@ class LSmiUntag: public LTemplateInstruction<1, 1, 0> {
   LOperand* value() { return inputs_[0]; }
   bool needs_check() const { return needs_check_; }
 
-  DECLARE_HYDROGEN_ACCESSOR(Change);
   DECLARE_CONCRETE_INSTRUCTION(SmiUntag, "smi-untag")
 
  private: