Allow uint32 value on optimized frames if they are consumed by safe operations.

src/ia32/lithium-codegen-ia32.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 431 matching lines @@
   for (int i = 0; i < translation_size; ++i) {
     LOperand* value = environment->values()->at(i);
     // spilled_registers_ and spilled_double_registers_ are either
     // both NULL or both set.
     if (environment->spilled_registers() != NULL && value != NULL) {
       if (value->IsRegister() &&
           environment->spilled_registers()[value->index()] != NULL) {
         translation->MarkDuplicate();
         AddToTranslation(translation,
                          environment->spilled_registers()[value->index()],
-                         environment->HasTaggedValueAt(i));
+                         environment->HasTaggedValueAt(i),
+                         environment->HasUint32ValueAt(i));
       } else if (
           value->IsDoubleRegister() &&
           environment->spilled_double_registers()[value->index()] != NULL) {
         translation->MarkDuplicate();
         AddToTranslation(
             translation,
             environment->spilled_double_registers()[value->index()],
+            false,
             false);
       }
     }
 
-    AddToTranslation(translation, value, environment->HasTaggedValueAt(i));
+    AddToTranslation(translation,
+                     value,
+                     environment->HasTaggedValueAt(i),
+                     environment->HasUint32ValueAt(i));
   }
 }
 
 
 void LCodeGen::AddToTranslation(Translation* translation,
                                 LOperand* op,
-                                bool is_tagged) {
+                                bool is_tagged,
+                                bool is_uint32) {
   if (op == NULL) {
     // TODO(twuerthinger): Introduce marker operands to indicate that this value
     // is not present and must be reconstructed from the deoptimizer. Currently
     // this is only used for the arguments object.
     translation->StoreArgumentsObject();
   } else if (op->IsStackSlot()) {
     if (is_tagged) {
       translation->StoreStackSlot(op->index());
+    } else if (is_uint32) {
+      translation->StoreUint32StackSlot(op->index());
     } else {
       translation->StoreInt32StackSlot(op->index());
     }
   } else if (op->IsDoubleStackSlot()) {
     translation->StoreDoubleStackSlot(op->index());
   } else if (op->IsArgument()) {
     ASSERT(is_tagged);
     int src_index = GetStackSlotCount() + op->index();
     translation->StoreStackSlot(src_index);
   } else if (op->IsRegister()) {
     Register reg = ToRegister(op);
     if (is_tagged) {
       translation->StoreRegister(reg);
+    } else if (is_uint32) {
+      translation->StoreUint32Register(reg);
     } else {
       translation->StoreInt32Register(reg);
     }
   } else if (op->IsDoubleRegister()) {
     XMMRegister reg = ToDoubleRegister(op);
     translation->StoreDoubleRegister(reg);
   } else if (op->IsConstantOperand()) {
     HConstant* constant = chunk()->LookupConstant(LConstantOperand::cast(op));
     int src_index = DefineDeoptimizationLiteral(constant->handle());
     translation->StoreLiteral(src_index);
@@ skipping 2325 matching lines @@
         __ movsx_w(result, operand);
         break;
       case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
         __ movzx_w(result, operand);
         break;
       case EXTERNAL_INT_ELEMENTS:
         __ mov(result, operand);
         break;
       case EXTERNAL_UNSIGNED_INT_ELEMENTS:
         __ mov(result, operand);
-        __ test(result, Operand(result));
-        // TODO(danno): we could be more clever here, perhaps having a special
-        // version of the stub that detects if the overflow case actually
-        // happens, and generate code that returns a double rather than int.
-        DeoptimizeIf(negative, instr->environment());
+        if (!instr->hydrogen()->CheckFlag(HInstruction::kUint32)) {
+          __ test(result, Operand(result));
+          DeoptimizeIf(negative, instr->environment());
+        }
         break;
       case EXTERNAL_FLOAT_ELEMENTS:
       case EXTERNAL_DOUBLE_ELEMENTS:
       case FAST_SMI_ELEMENTS:
       case FAST_ELEMENTS:
       case FAST_DOUBLE_ELEMENTS:
       case FAST_HOLEY_SMI_ELEMENTS:
       case FAST_HOLEY_ELEMENTS:
       case FAST_HOLEY_DOUBLE_ELEMENTS:
       case DICTIONARY_ELEMENTS:
@@ skipping 1198 matching lines @@
 
 void LCodeGen::DoInteger32ToDouble(LInteger32ToDouble* instr) {
   LOperand* input = instr->InputAt(0);
   ASSERT(input->IsRegister() || input->IsStackSlot());
   LOperand* output = instr->result();
   ASSERT(output->IsDoubleRegister());
   __ cvtsi2sd(ToDoubleRegister(output), ToOperand(input));
 }
 
 
+void LCodeGen::DoUint32ToDouble(LUint32ToDouble* instr) {
+  LOperand* input = instr->InputAt(0);
+  LOperand* output = instr->result();
+  LOperand* temp = instr->TempAt(0);
+
+  __ LoadUint32(ToDoubleRegister(output),
+                ToRegister(input),
+                ToDoubleRegister(temp));
+}
+
+
 void LCodeGen::DoNumberTagI(LNumberTagI* instr) {
   class DeferredNumberTagI: public LDeferredCode {
    public:
     DeferredNumberTagI(LCodeGen* codegen, LNumberTagI* instr)
         : LDeferredCode(codegen), instr_(instr) { }
-    virtual void Generate() { codegen()->DoDeferredNumberTagI(instr_); }
+    virtual void Generate() {
+      codegen()->DoDeferredNumberTagI(instr_, SIGNED_INT32);
+    }
     virtual LInstruction* instr() { return instr_; }
    private:
     LNumberTagI* instr_;
   };
 
   LOperand* input = instr->InputAt(0);
   ASSERT(input->IsRegister() && input->Equals(instr->result()));
   Register reg = ToRegister(input);
 
   DeferredNumberTagI* deferred = new(zone()) DeferredNumberTagI(this, instr);
   __ SmiTag(reg);
   __ j(overflow, deferred->entry());
   __ bind(deferred->exit());
 }
 
 
-void LCodeGen::DoDeferredNumberTagI(LNumberTagI* instr) {
+void LCodeGen::DoNumberTagU(LNumberTagU* instr) {
+  class DeferredNumberTagU: public LDeferredCode {
+   public:
+    DeferredNumberTagU(LCodeGen* codegen, LNumberTagU* instr)
+        : LDeferredCode(codegen), instr_(instr) { }
+    virtual void Generate() {
+      codegen()->DoDeferredNumberTagI(instr_, UNSIGNED_INT32);
+    }
+    virtual LInstruction* instr() { return instr_; }
+   private:
+    LNumberTagU* instr_;
+  };
+
+  LOperand* input = instr->InputAt(0);
+  ASSERT(input->IsRegister() && input->Equals(instr->result()));
+  Register reg = ToRegister(input);
+
+  DeferredNumberTagU* deferred = new(zone()) DeferredNumberTagU(this, instr);
+  __ cmp(reg, Immediate(Smi::kMaxValue));
+  __ j(above, deferred->entry());
+  __ SmiTag(reg);
+  __ bind(deferred->exit());
+}
+
+
+void LCodeGen::DoDeferredNumberTagI(LInstruction* instr,
+                                    IntegerSignedness signedness) {
   Label slow;
   Register reg = ToRegister(instr->InputAt(0));
   Register tmp = reg.is(eax) ? ecx : eax;
 
   // Preserve the value of all registers.
   PushSafepointRegistersScope scope(this);
 
-  // There was overflow, so bits 30 and 31 of the original integer
-  // disagree. Try to allocate a heap number in new space and store
-  // the value in there. If that fails, call the runtime system.
   Label done;
-  __ SmiUntag(reg);
-  __ xor_(reg, 0x80000000);
-  __ cvtsi2sd(xmm0, Operand(reg));
+
+  if (signedness == SIGNED_INT32) {
+    // There was overflow, so bits 30 and 31 of the original integer
+    // disagree. Try to allocate a heap number in new space and store
+    // the value in there. If that fails, call the runtime system.
+    __ SmiUntag(reg);
+    __ xor_(reg, 0x80000000);
+    __ cvtsi2sd(xmm0, Operand(reg));
+  } else {
+    __ LoadUint32(xmm0, reg, xmm1);
+  }
+
   if (FLAG_inline_new) {
     __ AllocateHeapNumber(reg, tmp, no_reg, &slow);
     __ jmp(&done, Label::kNear);
   }
 
   // Slow case: Call the runtime system to do the number allocation.
   __ bind(&slow);
 
   // TODO(3095996): Put a valid pointer value in the stack slot where the result
   // register is stored, as this register is in the pointer map, but contains an
@@ skipping 1314 matching lines @@
                               FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32