[turbofan] add non fixed slot constraint to register allocator

src/compiler/register-allocator-verifier.cc

Index: src/compiler/register-allocator-verifier.cc
diff --git a/src/compiler/register-allocator-verifier.cc b/src/compiler/register-allocator-verifier.cc
index c7ebd3c51029c3f825920014367b7a586590613d..c57591dfb4613d94c9a2d22d17687b562555e316 100644
--- a/src/compiler/register-allocator-verifier.cc
+++ b/src/compiler/register-allocator-verifier.cc
@@ -162,6 +162,13 @@ void RegisterAllocatorVerifier::BuildConstraint(const InstructionOperand* op,
             constraint->type_ = kRegister;
           }
           break;
+        case UnallocatedOperand::MUST_HAVE_SLOT:
+          if (sequence()->IsDouble(vreg)) {
+            constraint->type_ = kDoubleSlot;
+          } else {
+            constraint->type_ = kSlot;
+          }
+          break;
         case UnallocatedOperand::SAME_AS_FIRST_INPUT:
           constraint->type_ = kSameAsFirst;
           break;
@@ -200,6 +207,12 @@ void RegisterAllocatorVerifier::CheckConstraint(
       CHECK(op->IsStackSlot());
       CHECK_EQ(op->index(), constraint->value_);
       return;
+    case kSlot:
+      CHECK(op->IsStackSlot());
+      return;
+    case kDoubleSlot:
+      CHECK(op->IsDoubleStackSlot());
+      return;
     case kNone:
       CHECK(op->IsRegister() || op->IsStackSlot());
       return;
@@ -301,7 +314,10 @@ class OperandMap : public ZoneObject {
       if (i->IsEliminated()) continue;
       auto cur = map().find(i->source());
       CHECK(cur != map().end());
-      to_insert.insert(std::make_pair(i->destination(), cur->second));
+      auto res =
+          to_insert.insert(std::make_pair(i->destination(), cur->second));
+      // Ensure injectivity of moves.
+      CHECK(res.second);
     }
     // Drop current mappings.
     for (auto i = moves->begin(); i != moves->end(); ++i) {