[turbofan] Use special constant type for RPO block number operands.

src/compiler/arm/code-generator-arm.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/code-generator.h"
 
 #include "src/arm/macro-assembler-arm.h"
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
@@ skipping 59 matching lines @@
         return Operand(constant.ToInt32());
       case Constant::kFloat32:
         return Operand(
             isolate()->factory()->NewNumber(constant.ToFloat32(), TENURED));
       case Constant::kFloat64:
         return Operand(
             isolate()->factory()->NewNumber(constant.ToFloat64(), TENURED));
       case Constant::kInt64:
       case Constant::kExternalReference:
       case Constant::kHeapObject:
+      case Constant::kRpoNumber:
         break;
     }
     UNREACHABLE();
     return Operand::Zero();
   }
 
   Operand InputOperand2(int first_index) {
     const int index = first_index;
     switch (AddressingModeField::decode(instr_->opcode())) {
       case kMode_None:
@@ skipping 724 matching lines @@
         case Constant::kFloat64:
           __ Move(dst,
                   isolate()->factory()->NewNumber(src.ToFloat64(), TENURED));
           break;
         case Constant::kExternalReference:
           __ mov(dst, Operand(src.ToExternalReference()));
           break;
         case Constant::kHeapObject:
           __ Move(dst, src.ToHeapObject());
           break;
+        case Constant::kRpoNumber:
+          UNREACHABLE();  // TODO(dcarney): loading RPO constants on arm.
+          break;
       }
       if (destination->IsStackSlot()) __ str(dst, g.ToMemOperand(destination));
     } else if (src.type() == Constant::kFloat32) {
       SwVfpRegister dst = destination->IsDoubleRegister()
                               ? g.ToFloat32Register(destination)
                               : kScratchDoubleReg.low();
       // TODO(turbofan): Can we do better here?
       __ mov(ip, Operand(bit_cast<int32_t>(src.ToFloat32())));
       __ vmov(dst, ip);
       if (destination->IsDoubleStackSlot()) {
@@ skipping 124 matching lines @@
     }
   }
   MarkLazyDeoptSite();
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8