ARM: Support DoCheckInstanceType in lithium codegenerator.

src/arm/lithium-codegen-arm.cc

 // Copyright 2010 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 2138 matching lines @@
 
 void LCodeGen::DoCheckSmi(LCheckSmi* instr) {
   LOperand* input = instr->input();
   ASSERT(input->IsRegister());
   __ tst(ToRegister(input), Operand(kSmiTagMask));
   DeoptimizeIf(instr->condition(), instr->environment());
 }
 
 
 void LCodeGen::DoCheckInstanceType(LCheckInstanceType* instr) {
-  Abort("DoCheckInstanceType unimplemented.");
+  Register input = ToRegister(instr->input());
+  Register scratch = scratch0();
+  InstanceType first = instr->hydrogen()->first();
+  InstanceType last = instr->hydrogen()->last();
+
+  __ ldr(scratch, FieldMemOperand(input, HeapObject::kMapOffset));
+  __ ldrb(scratch, FieldMemOperand(scratch, Map::kInstanceTypeOffset));
+  __ cmp(scratch, Operand(first));
+
+  // If there is only one type in the interval check for equality.
+  if (first == last) {
+    DeoptimizeIf(ne, instr->environment());
+  } else {
+    DeoptimizeIf(lo, instr->environment());
+    // Omit check for the last type.
+    if (last != LAST_TYPE) {
+      __ cmp(scratch, Operand(last));
+      DeoptimizeIf(hi, instr->environment());
+    }
+  }
 }
 
 
 void LCodeGen::DoCheckFunction(LCheckFunction* instr) {
   ASSERT(instr->input()->IsRegister());
   Register reg = ToRegister(instr->input());
   __ cmp(reg, Operand(instr->hydrogen()->target()));
   DeoptimizeIf(ne, instr->environment());
 }
 
@@ skipping 292 matching lines @@
 
 
 void LCodeGen::DoOsrEntry(LOsrEntry* instr) {
   Abort("DoOsrEntry unimplemented.");
 }
 
 
 #undef __
 
 } }  // namespace v8::internal