Revert "[objects] Remove uncached internal external string type"

This reverts commit b3d09001.

Reason for revert: https://chromium-review.googlesource.com/c/v8/v8/+/2565511 has to be reverted, and this was a follow-up to that

Original change's description:
> [objects] Remove uncached internal external string type
>
> We shouldn't be creating those anymore since they are not thread-safe.
>
> Bug: v8:7790
> Change-Id: I4546d995fa32eb076c8dfe9d95301fad719c9e07
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2615347
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#72006}

TBR=rmcilroy@chromium.org,leszeks@chromium.org,solanes@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: v8:7790
Change-Id: I4eb1a6b8446fa602eeb5bf29fbf1fe57182cdbf3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2627605Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72122}

src/compiler/types.cc

@@ -153,6 +153,8 @@ Type::bitset BitsetType::Lub(const MapRefLike& map) {
       return kString;
     case EXTERNAL_INTERNALIZED_STRING_TYPE:
     case EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE:
+    case UNCACHED_EXTERNAL_INTERNALIZED_STRING_TYPE:
+    case UNCACHED_EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE:
     case INTERNALIZED_STRING_TYPE:
     case ONE_BYTE_INTERNALIZED_STRING_TYPE:
       return kInternalizedString;

src/diagnostics/objects-printer.cc

@@ -232,6 +232,8 @@ void HeapObject::HeapObjectPrint(std::ostream& os) {  // NOLINT
     case EXTERNAL_INTERNALIZED_STRING_TYPE:
     case ONE_BYTE_INTERNALIZED_STRING_TYPE:
     case EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE:
+    case UNCACHED_EXTERNAL_INTERNALIZED_STRING_TYPE:
+    case UNCACHED_EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE:
     case STRING_TYPE:
     case CONS_STRING_TYPE:
     case EXTERNAL_STRING_TYPE:

src/objects/instance-type.h

@@ -87,6 +87,12 @@ enum InstanceType : uint16_t {
       kTwoByteStringTag | kExternalStringTag | kInternalizedTag,
   EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE =
       kOneByteStringTag | kExternalStringTag | kInternalizedTag,
+  UNCACHED_EXTERNAL_INTERNALIZED_STRING_TYPE =
+      EXTERNAL_INTERNALIZED_STRING_TYPE | kUncachedExternalStringTag |
+      kInternalizedTag,
+  UNCACHED_EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE =
+      EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE | kUncachedExternalStringTag |
+      kInternalizedTag,
   STRING_TYPE = INTERNALIZED_STRING_TYPE | kNotInternalizedTag,
   ONE_BYTE_STRING_TYPE =
       ONE_BYTE_INTERNALIZED_STRING_TYPE | kNotInternalizedTag,
@@ -101,12 +107,10 @@ enum InstanceType : uint16_t {
       EXTERNAL_INTERNALIZED_STRING_TYPE | kNotInternalizedTag,
   EXTERNAL_ONE_BYTE_STRING_TYPE =
       EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE | kNotInternalizedTag,
-  UNCACHED_EXTERNAL_STRING_TYPE = kTwoByteStringTag | kExternalStringTag |
-                                  kUncachedExternalStringTag |
-                                  kNotInternalizedTag,
+  UNCACHED_EXTERNAL_STRING_TYPE =
+      UNCACHED_EXTERNAL_INTERNALIZED_STRING_TYPE | kNotInternalizedTag,
   UNCACHED_EXTERNAL_ONE_BYTE_STRING_TYPE =
-      kOneByteStringTag | kExternalStringTag | kUncachedExternalStringTag |
-      kNotInternalizedTag,
+      UNCACHED_EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE | kNotInternalizedTag,
   THIN_STRING_TYPE = kTwoByteStringTag | kThinStringTag | kNotInternalizedTag,
   THIN_ONE_BYTE_STRING_TYPE =
       kOneByteStringTag | kThinStringTag | kNotInternalizedTag,

src/objects/objects-definitions.h

@@ -36,6 +36,8 @@ namespace internal {
   V(EXTERNAL_INTERNALIZED_STRING_TYPE)                   \
   V(ONE_BYTE_INTERNALIZED_STRING_TYPE)                   \
   V(EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE)          \
+  V(UNCACHED_EXTERNAL_INTERNALIZED_STRING_TYPE)          \
+  V(UNCACHED_EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE) \
   V(STRING_TYPE)                                         \
   V(CONS_STRING_TYPE)                                    \
   V(EXTERNAL_STRING_TYPE)                                \
@@ -83,6 +85,13 @@ namespace internal {
     external_internalized_string, ExternalInternalizedString)                  \
   V(EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE, ExternalOneByteString::kSize,  \
     external_one_byte_internalized_string, ExternalOneByteInternalizedString)  \
+  V(UNCACHED_EXTERNAL_INTERNALIZED_STRING_TYPE,                                \
+    ExternalTwoByteString::kUncachedSize,                                      \
+    uncached_external_internalized_string, UncachedExternalInternalizedString) \
+  V(UNCACHED_EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE,                       \
+    ExternalOneByteString::kUncachedSize,                                      \
+    uncached_external_one_byte_internalized_string,                            \
+    UncachedExternalOneByteInternalizedString)                                 \
   V(THIN_STRING_TYPE, ThinString::kSize, thin_string, ThinString)              \
   V(THIN_ONE_BYTE_STRING_TYPE, ThinString::kSize, thin_one_byte_string,        \
     ThinOneByteString)

src/roots/roots.h

@@ -129,6 +129,10 @@ class Symbol;
   V(Map, external_internalized_string_map, ExternalInternalizedStringMap)      \
   V(Map, external_one_byte_internalized_string_map,                            \
     ExternalOneByteInternalizedStringMap)                                      \
+  V(Map, uncached_external_internalized_string_map,                            \
+    UncachedExternalInternalizedStringMap)                                     \
+  V(Map, uncached_external_one_byte_internalized_string_map,                   \
+    UncachedExternalOneByteInternalizedStringMap)                              \
   V(Map, uncached_external_one_byte_string_map,                                \
     UncachedExternalOneByteStringMap)                                          \
   /* Oddball maps */                                                           \

test/cctest/test-strings.cc

@@ -2140,6 +2140,7 @@ TEST(InternalizeExternalStringUncachedWithCopyTwoByte) {
   CHECK(external->is_uncached());
 
   // Internalize succesfully, with a copy.
+  CHECK(!external->IsInternalizedString());
   Handle<String> internal = factory->InternalizeString(external);
   CHECK(!external->IsInternalizedString());
   CHECK(internal->IsInternalizedString());

tools/heap-stats/categories.js

@@ -94,6 +94,8 @@ export const CATEGORIES = new Map([
       'SYMBOL_TYPE',
       'THIN_ONE_BYTE_STRING_TYPE',
       'THIN_STRING_TYPE',
+      'UNCACHED_EXTERNAL_INTERNALIZED_STRING_TYPE',
+      'UNCACHED_EXTERNAL_ONE_BYTE_INTERNALIZED_STRING_TYPE',
       'UNCACHED_EXTERNAL_ONE_BYTE_STRING_TYPE',
       'UNCACHED_EXTERNAL_STRING_TYPE',
       'WASM_INSTANCE_OBJECT_TYPE',