Optimize Smi keys for KeyedLoads

src/arm/lithium-arm.cc

Index: src/arm/lithium-arm.cc
diff --git a/src/arm/lithium-arm.cc b/src/arm/lithium-arm.cc
index 4f63b50a50d467978e2fa5e5841a28b3161fee02..91afec53b1fa48b07f5409b671d984efc6ac2d9c 100644
--- a/src/arm/lithium-arm.cc
+++ b/src/arm/lithium-arm.cc
@@ -1835,7 +1835,8 @@ LInstruction* LChunkBuilder::DoLoadExternalArrayPointer(
 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 = UseRegisterAtStart(instr->key());
   LLoadKeyedFastElement* result = new(zone()) LLoadKeyedFastElement(obj, key);
@@ -1847,7 +1848,8 @@ LInstruction* LChunkBuilder::DoLoadKeyedFastElement(
 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 = UseTempRegister(instr->elements());
   LOperand* key = UseRegisterOrConstantAtStart(instr->key());
   LLoadKeyedFastDoubleElement* result =
@@ -1866,7 +1868,8 @@ LInstruction* LChunkBuilder::DoLoadKeyedSpecializedArrayElement(
       (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());
   LLoadKeyedSpecializedArrayElement* result =
@@ -1894,7 +1897,8 @@ LInstruction* LChunkBuilder::DoStoreKeyedFastElement(
   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 = UseTempRegister(instr->object());
   LOperand* val = needs_write_barrier
@@ -1911,7 +1915,8 @@ 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());
@@ -1932,7 +1937,8 @@ LInstruction* LChunkBuilder::DoStoreKeyedSpecializedArrayElement(
        ((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());
   bool val_is_temp_register =