MIPS: Re-land Crankshaft-generated KeyedLoad stubs.

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 0e58eb55104ae3abe77bf53c9a427eda36a1b901..b883ad459eb1879a6ccce5724d2d87784d91337c 100644
--- a/src/mips/lithium-mips.cc
+++ b/src/mips/lithium-mips.cc
@@ -42,10 +42,10 @@ LITHIUM_CONCRETE_INSTRUCTION_LIST(DEFINE_COMPILE)
 #undef DEFINE_COMPILE
 
 LOsrEntry::LOsrEntry() {
-  for (int i = 0; i < Register::kNumAllocatableRegisters; ++i) {
+  for (int i = 0; i < Register::NumAllocatableRegisters(); ++i) {
     register_spills_[i] = NULL;
   }
-  for (int i = 0; i < DoubleRegister::kNumAllocatableRegisters; ++i) {
+  for (int i = 0; i < DoubleRegister::NumAllocatableRegisters(); ++i) {
     double_register_spills_[i] = NULL;
   }
 }
@@ -616,6 +616,7 @@ LInstruction* LChunkBuilder::AssignEnvironment(LInstruction* instr) {
 LInstruction* LChunkBuilder::MarkAsCall(LInstruction* instr,
                                         HInstruction* hinstr,
                                         CanDeoptimize can_deoptimize) {
+  info()->MarkAsNonDeferredCalling();
 #ifdef DEBUG
   instr->VerifyCall();
 #endif
@@ -1583,6 +1584,7 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
   Representation to = instr->to();
   if (from.IsTagged()) {
     if (to.IsDouble()) {
+      info()->MarkAsDeferredCalling();
       LOperand* value = UseRegister(instr->value());
       LNumberUntagD* res = new(zone()) LNumberUntagD(value);
       return AssignEnvironment(DefineAsRegister(res));
@@ -1607,6 +1609,7 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
     }
   } else if (from.IsDouble()) {
     if (to.IsTagged()) {
+      info()->MarkAsDeferredCalling();
       LOperand* value = UseRegister(instr->value());
       LOperand* temp1 = TempRegister();
       LOperand* temp2 = TempRegister();
@@ -1626,6 +1629,7 @@ LInstruction* LChunkBuilder::DoChange(HChange* instr) {
       return AssignEnvironment(DefineAsRegister(res));
     }
   } else if (from.IsInteger32()) {
+    info()->MarkAsDeferredCalling();
     if (to.IsTagged()) {
       HValue* val = instr->value();
       LOperand* value = UseRegisterAtStart(val);
@@ -1864,7 +1868,16 @@ LInstruction* LChunkBuilder::DoLoadKeyed(HLoadKeyed* instr) {
         (instr->representation().IsDouble() &&
          ((elements_kind == EXTERNAL_FLOAT_ELEMENTS) ||
           (elements_kind == EXTERNAL_DOUBLE_ELEMENTS))));
-    LOperand* external_pointer = UseRegister(instr->elements());
+    // float->double conversion on non-VFP2 requires an extra scratch
+    // register. For convenience, just mark the elements register as "UseTemp"
+    // so that it can be used as a temp during the float->double conversion
+    // after it's no longer needed after the float load.
+    bool needs_temp =
+        !CpuFeatures::IsSupported(FPU) &&
+        (elements_kind == EXTERNAL_FLOAT_ELEMENTS);
+    LOperand* external_pointer = needs_temp
+        ? UseTempRegister(instr->elements())
+        : UseRegister(instr->elements());
     result = new(zone()) LLoadKeyed(external_pointer, key);
   }
 
@@ -2083,8 +2096,17 @@ LInstruction* LChunkBuilder::DoOsrEntry(HOsrEntry* instr) {
 
 
 LInstruction* LChunkBuilder::DoParameter(HParameter* instr) {
-  int spill_index = chunk()->GetParameterStackSlot(instr->index());
-  return DefineAsSpilled(new(zone()) LParameter, spill_index);
+  LParameter* result = new(zone()) LParameter;
+  if (info()->IsOptimizing()) {
+    int spill_index = chunk()->GetParameterStackSlot(instr->index());
+    return DefineAsSpilled(result, spill_index);
+  } else {
+    ASSERT(info()->IsStub());
+    CodeStubInterfaceDescriptor* descriptor =
+        info()->code_stub()->GetInterfaceDescriptor(info()->isolate());
+    Register reg = descriptor->register_params_[instr->index()];
+    return DefineFixed(result, reg);
+  }
 }