Replace ASSUME(false) with Unreachable() for clearer intent.
They have the same optimization effect.

PiperOrigin-RevId: 583455660
diff --git a/src/google/protobuf/extension_set.h b/src/google/protobuf/extension_set.h
index 74a316e..d8ca802 100644
--- a/src/google/protobuf/extension_set.h
+++ b/src/google/protobuf/extension_set.h
@@ -789,7 +789,7 @@
         // someone
         // adds a new wire type.
     }
-    PROTOBUF_ASSUME(false);  // switch handles all possible enum values
+    Unreachable();  // switch handles all possible enum values
     return false;
   }
 
diff --git a/src/google/protobuf/generated_message_tctable_decl.h b/src/google/protobuf/generated_message_tctable_decl.h
index 55057a6..72b703b 100644
--- a/src/google/protobuf/generated_message_tctable_decl.h
+++ b/src/google/protobuf/generated_message_tctable_decl.h
@@ -238,7 +238,7 @@
 
     case WireFormatLite::TYPE_GROUP:
     default:
-      PROTOBUF_ASSUME(false);
+      Unreachable();
   }
 }
 
diff --git a/src/google/protobuf/generated_message_tctable_gen.cc b/src/google/protobuf/generated_message_tctable_gen.cc
index 6740e35..1a64e6e 100644
--- a/src/google/protobuf/generated_message_tctable_gen.cc
+++ b/src/google/protobuf/generated_message_tctable_gen.cc
@@ -713,7 +713,7 @@
         }
         break;
       default:
-        PROTOBUF_ASSUME(false);
+        Unreachable();
     }
   }
 
diff --git a/src/google/protobuf/generated_message_tctable_lite.cc b/src/google/protobuf/generated_message_tctable_lite.cc
index e37a208..ed09b87 100644
--- a/src/google/protobuf/generated_message_tctable_lite.cc
+++ b/src/google/protobuf/generated_message_tctable_lite.cc
@@ -27,6 +27,7 @@
 #include "google/protobuf/map.h"
 #include "google/protobuf/message_lite.h"
 #include "google/protobuf/parse_context.h"
+#include "google/protobuf/port.h"
 #include "google/protobuf/repeated_field.h"
 #include "google/protobuf/repeated_ptr_field.h"
 #include "google/protobuf/varint_shuffle.h"
@@ -2013,14 +2014,14 @@
               is_split, uint32_t, (is_split ? 0 : field_layout::kTvRange)>(
               PROTOBUF_TC_PARAM_PASS);
         default:
-          PROTOBUF_ASSUME(false);
+          Unreachable();
       }
     case field_layout::kRep8Bits >> field_layout::kRepShift:
       PROTOBUF_MUSTTAIL return MpRepeatedVarintT<is_split, bool, 0>(
           PROTOBUF_TC_PARAM_PASS);
 
     default:
-      PROTOBUF_ASSUME(false);
+      Unreachable();
       return nullptr;  // To silence -Werror=return-type in some toolchains
   }
 }
@@ -2110,14 +2111,14 @@
               is_split, uint32_t, (is_split ? 0 : field_layout::kTvRange)>(
               PROTOBUF_TC_PARAM_PASS);
         default:
-          PROTOBUF_ASSUME(false);
+          Unreachable();
       }
     case field_layout::kRep8Bits >> field_layout::kRepShift:
       PROTOBUF_MUSTTAIL return MpPackedVarintT<is_split, bool, 0>(
           PROTOBUF_TC_PARAM_PASS);
 
     default:
-      PROTOBUF_ASSUME(false);
+      Unreachable();
       return nullptr;  // To silence -Werror=return-type in some toolchains
   }
 }
@@ -2216,7 +2217,7 @@
     }
 
     default:
-      PROTOBUF_ASSUME(false);
+      Unreachable();
   }
 
   if (PROTOBUF_PREDICT_FALSE(ptr == nullptr || !is_valid)) {
@@ -2503,7 +2504,7 @@
           }
           break;
         default:
-          PROTOBUF_ASSUME(false);
+          Unreachable();
       }
       break;
     case WireFormatLite::WIRETYPE_FIXED32:
@@ -2522,7 +2523,7 @@
           &coded_output);
       break;
     default:
-      PROTOBUF_ASSUME(false);
+      Unreachable();
   }
 }
 
@@ -2567,7 +2568,7 @@
       aux[1].create_in_arena(map.arena(), reinterpret_cast<MessageLite*>(obj));
       break;
     default:
-      PROTOBUF_ASSUME(false);
+      Unreachable();
   }
 }
 
@@ -2661,7 +2662,7 @@
             memcpy(obj, &tmp, sizeof(tmp));
             continue;
           default:
-            PROTOBUF_ASSUME(false);
+            Unreachable();
         }
       case WFL::WIRETYPE_FIXED32:
         ptr = ReadFixed<uint32_t>(obj, ptr);
@@ -2697,7 +2698,7 @@
           continue;
         }
       default:
-        PROTOBUF_ASSUME(false);
+        Unreachable();
     }
   }
   return ptr;
@@ -2772,7 +2773,7 @@
                     static_cast<KeyMapBase<std::string>::KeyNode*>(node));
             break;
           default:
-            PROTOBUF_ASSUME(false);
+            Unreachable();
         }
       }
     }
diff --git a/src/google/protobuf/map_field.cc b/src/google/protobuf/map_field.cc
index 0d70c65..6496d71 100644
--- a/src/google/protobuf/map_field.cc
+++ b/src/google/protobuf/map_field.cc
@@ -38,7 +38,7 @@
     case FieldDescriptor::CPPTYPE_BOOL:
       return VariantKey(static_cast<uint64_t>(value.GetBoolValue()));
     default:
-      ABSL_ASSUME(false);
+      Unreachable();
       return VariantKey(uint64_t{});
   }
 }
@@ -246,7 +246,7 @@
         reflection->SetBool(new_entry, key_des, map_key.GetBoolValue());
         break;
       default:
-        PROTOBUF_ASSUME(false);
+        Unreachable();
     }
 
     const MapValueRef& map_val = it.GetValueRef();
@@ -342,7 +342,7 @@
         map_key.SetBoolValue(reflection->GetBool(elem, key_des));
         break;
       default:
-        PROTOBUF_ASSUME(false);
+        Unreachable();
     }
 
     MapValueRef map_val;