[turbofan] Introduces the BitcastWordToTaggedSigned and BitcastTaggedToWord opcodes.

src/compiler/raw-machine-assembler.h

Index: src/compiler/raw-machine-assembler.h
diff --git a/src/compiler/raw-machine-assembler.h b/src/compiler/raw-machine-assembler.h
index 0e7219cfbe09eacc84d7a4b29f0d3dff551ae98b..cdd368ca7c206d0cce5169bdb6d05a9262621bd9 100644
--- a/src/compiler/raw-machine-assembler.h
+++ b/src/compiler/raw-machine-assembler.h
@@ -532,9 +532,15 @@ class RawMachineAssembler {
   }
 
   // Conversions.
+  Node* BitcastTaggedToWord(Node* a) {
+    return AddNode(machine()->BitcastTaggedToWord(), a);
+  }
   Node* BitcastWordToTagged(Node* a) {
     return AddNode(machine()->BitcastWordToTagged(), a);
   }
+  Node* BitcastWordToTaggedSigned(Node* a) {
+    return AddNode(machine()->BitcastWordToTaggedSigned(), a);
+  }
   Node* TruncateFloat64ToWord32(Node* a) {
     return AddNode(machine()->TruncateFloat64ToWord32(), a);
   }