Allow dispatch to use a range of Class-ids in tests

runtime/vm/assembler_arm.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // NOLINT
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/assembler.h"
 #include "vm/cpu.h"
 #include "vm/longjump.h"
@@ skipping 3029 matching lines @@
   } else if (Operand::CanHold(-value, &o)) {
     sub(rd, rn, o, cond);
   } else {
     ASSERT(rn != IP);
     if (Operand::CanHold(~value, &o)) {
       mvn(IP, o, cond);
       add(rd, rn, Operand(IP), cond);
     } else if (Operand::CanHold(~(-value), &o)) {
       mvn(IP, o, cond);
       sub(rd, rn, Operand(IP), cond);
-    } else {
+    } else if (value > 0) {
       LoadDecodableImmediate(IP, value, cond);
       add(rd, rn, Operand(IP), cond);
+    } else {
+      LoadDecodableImmediate(IP, -value, cond);
+      sub(rd, rn, Operand(IP), cond);
     }
   }
 }
 
 
 void Assembler::AddImmediateSetFlags(Register rd,
                                      Register rn,
                                      int32_t value,
                                      Condition cond) {
   Operand o;
@@ skipping 665 matching lines @@
 
 
 const char* Assembler::FpuRegisterName(FpuRegister reg) {
   ASSERT((0 <= reg) && (reg < kNumberOfFpuRegisters));
   return fpu_reg_names[reg];
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM