Optimize Smi keys for KeyedLoads

src/ia32/lithium-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 1882 matching lines @@
 LInstruction* LChunkBuilder::DoLoadExternalArrayPointer(
     HLoadExternalArrayPointer* instr) {
   LOperand* input = UseRegisterAtStart(instr->value());
   return DefineAsRegister(new(zone()) LLoadExternalArrayPointer(input));
 }
 
 
 LInstruction* LChunkBuilder::DoLoadKeyedFastElement(
     HLoadKeyedFastElement* instr) {
   ASSERT(instr->representation().IsTagged());
-  ASSERT(instr->key()->representation().IsInteger32());
+  ASSERT(instr->key()->representation().IsInteger32() ||
+         instr->key()->representation().IsTagged());
   LOperand* obj = UseRegisterAtStart(instr->object());
   LOperand* key = UseRegisterOrConstantAtStart(instr->key());
   LLoadKeyedFastElement* result = new(zone()) LLoadKeyedFastElement(obj, key);
   if (instr->RequiresHoleCheck()) AssignEnvironment(result);
   return DefineAsRegister(result);
 }
 
 
 LInstruction* LChunkBuilder::DoLoadKeyedFastDoubleElement(
     HLoadKeyedFastDoubleElement* instr) {
   ASSERT(instr->representation().IsDouble());
-  ASSERT(instr->key()->representation().IsInteger32());
+  ASSERT(instr->key()->representation().IsInteger32() ||
+         instr->key()->representation().IsTagged());
   LOperand* elements = UseRegisterAtStart(instr->elements());
   LOperand* key = UseRegisterOrConstantAtStart(instr->key());
   LLoadKeyedFastDoubleElement* result =
       new(zone()) LLoadKeyedFastDoubleElement(elements, key);
   return AssignEnvironment(DefineAsRegister(result));
 }
 
 
 LInstruction* LChunkBuilder::DoLoadKeyedSpecializedArrayElement(
     HLoadKeyedSpecializedArrayElement* instr) {
   ElementsKind elements_kind = instr->elements_kind();
   ASSERT(
       (instr->representation().IsInteger32() &&
        (elements_kind != EXTERNAL_FLOAT_ELEMENTS) &&
        (elements_kind != EXTERNAL_DOUBLE_ELEMENTS)) ||
       (instr->representation().IsDouble() &&
        ((elements_kind == EXTERNAL_FLOAT_ELEMENTS) ||
        (elements_kind == EXTERNAL_DOUBLE_ELEMENTS))));
-  ASSERT(instr->key()->representation().IsInteger32());
+  ASSERT(instr->key()->representation().IsInteger32() ||
+         instr->key()->representation().IsTagged());
   LOperand* external_pointer = UseRegister(instr->external_pointer());
-  LOperand* key = UseRegisterOrConstant(instr->key());
+  bool clobbers_key = ExternalArrayOpRequiresTemp(
+      instr->key()->representation(), elements_kind);
+  LOperand* key = clobbers_key
+      ? UseTempRegister(instr->key())
+      : UseRegisterOrConstant(instr->key());
+
   LLoadKeyedSpecializedArrayElement* result =
-      new(zone()) LLoadKeyedSpecializedArrayElement(external_pointer, key);
+    new(zone()) LLoadKeyedSpecializedArrayElement(external_pointer, key);
   LInstruction* load_instr = DefineAsRegister(result);
   // An unsigned int array load might overflow and cause a deopt, make sure it
   // has an environment.
   return (elements_kind == EXTERNAL_UNSIGNED_INT_ELEMENTS)
       ? AssignEnvironment(load_instr)
       : load_instr;
 }
 
 
 LInstruction* LChunkBuilder::DoLoadKeyedGeneric(HLoadKeyedGeneric* instr) {
   LOperand* context = UseFixed(instr->context(), esi);
   LOperand* object = UseFixed(instr->object(), edx);
   LOperand* key = UseFixed(instr->key(), ecx);
 
   LLoadKeyedGeneric* result =
       new(zone()) LLoadKeyedGeneric(context, object, key);
   return MarkAsCall(DefineFixed(result, eax), instr);
 }
 
 
 LInstruction* LChunkBuilder::DoStoreKeyedFastElement(
     HStoreKeyedFastElement* instr) {
   bool needs_write_barrier = instr->NeedsWriteBarrier();
   ASSERT(instr->value()->representation().IsTagged());
   ASSERT(instr->object()->representation().IsTagged());
-  ASSERT(instr->key()->representation().IsInteger32());
+  ASSERT(instr->key()->representation().IsInteger32() ||
+         instr->key()->representation().IsTagged());
 
   LOperand* obj = UseRegister(instr->object());
   LOperand* val = needs_write_barrier
       ? UseTempRegister(instr->value())
       : UseRegisterAtStart(instr->value());
   LOperand* key = needs_write_barrier
       ? UseTempRegister(instr->key())
       : UseRegisterOrConstantAtStart(instr->key());
   return new(zone()) LStoreKeyedFastElement(obj, key, val);
 }
 
 
 LInstruction* LChunkBuilder::DoStoreKeyedFastDoubleElement(
     HStoreKeyedFastDoubleElement* instr) {
   ASSERT(instr->value()->representation().IsDouble());
   ASSERT(instr->elements()->representation().IsTagged());
-  ASSERT(instr->key()->representation().IsInteger32());
+  ASSERT(instr->key()->representation().IsInteger32() ||
+         instr->key()->representation().IsTagged());
 
   LOperand* elements = UseRegisterAtStart(instr->elements());
   LOperand* val = UseTempRegister(instr->value());
   LOperand* key = UseRegisterOrConstantAtStart(instr->key());
 
   return new(zone()) LStoreKeyedFastDoubleElement(elements, key, val);
 }
 
 
 LInstruction* LChunkBuilder::DoStoreKeyedSpecializedArrayElement(
     HStoreKeyedSpecializedArrayElement* instr) {
   ElementsKind elements_kind = instr->elements_kind();
     ASSERT(
       (instr->value()->representation().IsInteger32() &&
        (elements_kind != EXTERNAL_FLOAT_ELEMENTS) &&
        (elements_kind != EXTERNAL_DOUBLE_ELEMENTS)) ||
       (instr->value()->representation().IsDouble() &&
        ((elements_kind == EXTERNAL_FLOAT_ELEMENTS) ||
        (elements_kind == EXTERNAL_DOUBLE_ELEMENTS))));
   ASSERT(instr->external_pointer()->representation().IsExternal());
-  ASSERT(instr->key()->representation().IsInteger32());
+  ASSERT(instr->key()->representation().IsInteger32() ||
+         instr->key()->representation().IsTagged());
 
   LOperand* external_pointer = UseRegister(instr->external_pointer());
-  LOperand* key = UseRegisterOrConstant(instr->key());
   LOperand* val = NULL;
   if (elements_kind == EXTERNAL_BYTE_ELEMENTS ||
       elements_kind == EXTERNAL_UNSIGNED_BYTE_ELEMENTS ||
       elements_kind == EXTERNAL_PIXEL_ELEMENTS) {
     // We need a byte register in this case for the value.
     val = UseFixed(instr->value(), eax);
   } else {
     val = UseRegister(instr->value());
   }
-
+  bool clobbers_key = ExternalArrayOpRequiresTemp(
+      instr->key()->representation(), elements_kind);
+  LOperand* key = clobbers_key
+      ? UseTempRegister(instr->key())
+      : UseRegisterOrConstant(instr->key());
   return new(zone()) LStoreKeyedSpecializedArrayElement(external_pointer,
                                                         key,
                                                         val);
 }
 
 
 LInstruction* LChunkBuilder::DoStoreKeyedGeneric(HStoreKeyedGeneric* instr) {
   LOperand* context = UseFixed(instr->context(), esi);
   LOperand* object = UseFixed(instr->object(), edx);
   LOperand* key = UseFixed(instr->key(), ecx);
@@ skipping 356 matching lines @@
 LInstruction* LChunkBuilder::DoLoadFieldByIndex(HLoadFieldByIndex* instr) {
   LOperand* object = UseRegister(instr->object());
   LOperand* index = UseTempRegister(instr->index());
   return DefineSameAsFirst(new(zone()) LLoadFieldByIndex(object, index));
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32