[turbofan] Simplify BinaryOperationHints and CompareOperationHints.

src/ic/ic-state.h

Index: src/ic/ic-state.h
diff --git a/src/ic/ic-state.h b/src/ic/ic-state.h
index b12b17d3e20b2eb3a04cecbc27189ceed5a1ffb3..ec33e8d0e9eec55497d15e074eebc214c4cd2ac7 100644
--- a/src/ic/ic-state.h
+++ b/src/ic/ic-state.h
@@ -128,11 +128,15 @@ class BinaryOpICState final BASE_EMBEDDED {
 
   Isolate* isolate() const { return isolate_; }
 
+  enum Kind { NONE, SMI, INT32, NUMBER, STRING, GENERIC };
+  Kind kind() const {
+    return KindGeneralize(KindGeneralize(left_kind_, right_kind_),
+                          result_kind_);
+  }
+
  private:
   friend std::ostream& operator<<(std::ostream& os, const BinaryOpICState& s);
 
-  enum Kind { NONE, SMI, INT32, NUMBER, STRING, GENERIC };
-
   Kind UpdateKind(Handle<Object> object, Kind kind) const;
 
   static const char* KindToString(Kind kind);
@@ -140,6 +144,18 @@ class BinaryOpICState final BASE_EMBEDDED {
   static bool KindMaybeSmi(Kind kind) {
     return (kind >= SMI && kind <= NUMBER) || kind == GENERIC;
   }
+  static bool KindLessGeneralThan(Kind kind1, Kind kind2) {
+    if (kind1 == NONE) return true;
+    if (kind1 == kind2) return true;
+    if (kind2 == GENERIC) return true;
+    if (kind2 == STRING) return false;
+    return kind1 <= kind2;
+  }
+  static Kind KindGeneralize(Kind kind1, Kind kind2) {
+    if (KindLessGeneralThan(kind1, kind2)) return kind2;
+    if (KindLessGeneralThan(kind2, kind1)) return kind1;
+    return GENERIC;
+  }
 
   // We truncate the last bit of the token.
   STATIC_ASSERT(LAST_TOKEN - FIRST_TOKEN < (1 << 4));