Merge bleeding_edge r17376:17693.

src/mips/lithium-mips.cc

Index: src/mips/lithium-mips.cc
diff --git a/src/mips/lithium-mips.cc b/src/mips/lithium-mips.cc
index fb94bc3bdf24a7639d241603207ba2a5fdf1a5ca..70dd60d6560cdb6a6938ff709130a72c0c00c101 100644
--- a/src/mips/lithium-mips.cc
+++ b/src/mips/lithium-mips.cc
@@ -868,10 +868,12 @@ void LChunkBuilder::VisitInstruction(HInstruction* current) {
 
   LInstruction* instr = NULL;
   if (current->CanReplaceWithDummyUses()) {
-    HValue* first_operand = current->OperandCount() == 0
-        ? graph()->GetConstant1()
-        : current->OperandAt(0);
-    instr = DefineAsRegister(new(zone()) LDummyUse(UseAny(first_operand)));
+    if (current->OperandCount() == 0) {
+      instr = DefineAsRegister(new(zone()) LDummy());
+    } else {
+      instr = DefineAsRegister(new(zone())
+          LDummyUse(UseAny(current->OperandAt(0))));
+    }
     for (int i = 1; i < current->OperandCount(); ++i) {
       LInstruction* dummy =
           new(zone()) LDummyUse(UseAny(current->OperandAt(i)));
@@ -1701,6 +1703,16 @@ LInstruction* LChunkBuilder::DoCompareHoleAndBranch(
 }
 
 
+LInstruction* LChunkBuilder::DoCompareMinusZeroAndBranch(
+    HCompareMinusZeroAndBranch* instr) {
+  LInstruction* goto_instr = CheckElideControlInstruction(instr);
+  if (goto_instr != NULL) return goto_instr;
+  LOperand* value = UseRegister(instr->value());
+  LOperand* scratch = TempRegister();
+  return new(zone()) LCompareMinusZeroAndBranch(value, scratch);
+}
+
+
 LInstruction* LChunkBuilder::DoIsObjectAndBranch(HIsObjectAndBranch* instr) {
   ASSERT(instr->value()->representation().IsTagged());
   LOperand* temp = TempRegister();
@@ -1804,11 +1816,18 @@ LInstruction* LChunkBuilder::DoDateField(HDateField* instr) {
 }
 
 
+LInstruction* LChunkBuilder::DoSeqStringGetChar(HSeqStringGetChar* instr) {
+  LOperand* string = UseRegisterAtStart(instr->string());
+  LOperand* index = UseRegisterOrConstantAtStart(instr->index());
+  return DefineAsRegister(new(zone()) LSeqStringGetChar(string, index));
+}
+
+
 LInstruction* LChunkBuilder::DoSeqStringSetChar(HSeqStringSetChar* instr) {
   LOperand* string = UseRegister(instr->string());
   LOperand* index = UseRegisterOrConstant(instr->index());
   LOperand* value = UseRegister(instr->value());
-  return new(zone()) LSeqStringSetChar(instr->encoding(), string, index, value);
+  return new(zone()) LSeqStringSetChar(string, index, value);
 }
 
 
@@ -1934,8 +1953,9 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
     } else if (to.IsSmi()) {
       HValue* val = instr->value();
       LOperand* value = UseRegister(val);
-      LInstruction* result =
-          DefineSameAsFirst(new(zone()) LInteger32ToSmi(value));
+      LInstruction* result = val->CheckFlag(HInstruction::kUint32)
+          ? DefineSameAsFirst(new(zone()) LUint32ToSmi(value))
+          : DefineSameAsFirst(new(zone()) LInteger32ToSmi(value));
       if (val->HasRange() && val->range()->IsInSmiRange()) {
         return result;
       }
@@ -2325,8 +2345,12 @@ LInstruction* LChunkBuilder::DoStoreNamedGeneric(HStoreNamedGeneric* instr) {
 
 LInstruction* LChunkBuilder::DoStringAdd(HStringAdd* instr) {
   LOperand* context = UseFixed(instr->context(), cp);
-  LOperand* left = UseRegisterAtStart(instr->left());
-  LOperand* right = UseRegisterAtStart(instr->right());
+  LOperand* left = FLAG_new_string_add
+      ? UseFixed(instr->left(), a1)
+      : UseRegisterAtStart(instr->left());
+  LOperand* right = FLAG_new_string_add
+      ? UseFixed(instr->right(), a0)
+      : UseRegisterAtStart(instr->right());
   return MarkAsCall(
       DefineFixed(new(zone()) LStringAdd(context, left, right), v0),
       instr);