deps: V8: cherry-pick 0188634

Original commit message:

    [ptr-compr][ubsan] Use [Read/Write]UnalignedValue for unaligned fields

    When pointer compression is enabled the [u]intptr_t and double fields are
    only kTaggedSize aligned so in order to avoid undefined behavior in C++ code
    we have to access these values in an unaligned pointer friendly way although
    both x64 and arm64 architectures (where pointer compression is supported)
    allow unaligned access.

    These changes will be removed once v8:8875 is fixed and all the
    kSystemPointerSize fields are properly aligned.

    Bug: v8:7703
    Change-Id: I4df477cbdeab806303bb4f675d52b61c06342c8e
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1528996
    Commit-Queue: Igor Sheludko <ishell@chromium.org>
    Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
    Reviewed-by: Jakob Gruber <jgruber@chromium.org>
    Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#60321}

Refs: https://github.com/v8/v8/commit/0188634ee523aef39ba71732b1ab9d422f449825

PR-URL: https://github.com/nodejs/node/pull/27013
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

1 files changed, 39 insertions, 35 deletions

diff --git a/deps/v8/src/objects/object-macros.h b/deps/v8/src/objects/object-macros.h
index 3b15d63e09..941c68a6a2 100644
--- a/deps/v8/src/objects/object-macros.h
+++ b/deps/v8/src/objects/object-macros.h
@@ -323,40 +323,10 @@
 #define WRITE_INT_FIELD(p, offset, value) \
   (*reinterpret_cast<int*>(FIELD_ADDR(p, offset)) = value)
 
-#define ACQUIRE_READ_INTPTR_FIELD(p, offset) \
-  static_cast<intptr_t>(base::Acquire_Load(  \
-      reinterpret_cast<const base::AtomicWord*>(FIELD_ADDR(p, offset))))
-
 #define ACQUIRE_READ_INT32_FIELD(p, offset) \
   static_cast<int32_t>(base::Acquire_Load(  \
       reinterpret_cast<const base::Atomic32*>(FIELD_ADDR(p, offset))))
 
-#define RELAXED_READ_INTPTR_FIELD(p, offset) \
-  static_cast<intptr_t>(base::Relaxed_Load(  \
-      reinterpret_cast<const base::AtomicWord*>(FIELD_ADDR(p, offset))))
-
-#define READ_INTPTR_FIELD(p, offset) \
-  (*reinterpret_cast<const intptr_t*>(FIELD_ADDR(p, offset)))
-
-#define RELEASE_WRITE_INTPTR_FIELD(p, offset, value)              \
-  base::Release_Store(                                            \
-      reinterpret_cast<base::AtomicWord*>(FIELD_ADDR(p, offset)), \
-      static_cast<base::AtomicWord>(value));
-
-#define RELAXED_WRITE_INTPTR_FIELD(p, offset, value)              \
-  base::Relaxed_Store(                                            \
-      reinterpret_cast<base::AtomicWord*>(FIELD_ADDR(p, offset)), \
-      static_cast<base::AtomicWord>(value));
-
-#define WRITE_INTPTR_FIELD(p, offset, value) \
-  (*reinterpret_cast<intptr_t*>(FIELD_ADDR(p, offset)) = value)
-
-#define READ_UINTPTR_FIELD(p, offset) \
-  (*reinterpret_cast<const uintptr_t*>(FIELD_ADDR(p, offset)))
-
-#define WRITE_UINTPTR_FIELD(p, offset, value) \
-  (*reinterpret_cast<uintptr_t*>(FIELD_ADDR(p, offset)) = value)
-
 #define READ_UINT8_FIELD(p, offset) \
   (*reinterpret_cast<const uint8_t*>(FIELD_ADDR(p, offset)))
 
@@ -439,17 +409,51 @@
 #define WRITE_FLOAT_FIELD(p, offset, value) \
   (*reinterpret_cast<float*>(FIELD_ADDR(p, offset)) = value)
 
+// TODO(ishell, v8:8875): When pointer compression is enabled 8-byte size fields
+// (external pointers, doubles and BigInt data) are only kTaggedSize aligned so
+// we have to use unaligned pointer friendly way of accessing them in order to
+// avoid undefined behavior in C++ code.
+#ifdef V8_COMPRESS_POINTERS
+
+#define READ_INTPTR_FIELD(p, offset) \
+  ReadUnalignedValue<intptr_t>(FIELD_ADDR(p, offset))
+
+#define WRITE_INTPTR_FIELD(p, offset, value) \
+  WriteUnalignedValue<intptr_t>(FIELD_ADDR(p, offset), value)
+
+#define READ_UINTPTR_FIELD(p, offset) \
+  ReadUnalignedValue<uintptr_t>(FIELD_ADDR(p, offset))
+
+#define WRITE_UINTPTR_FIELD(p, offset, value) \
+  WriteUnalignedValue<uintptr_t>(FIELD_ADDR(p, offset), value)
+
+#define READ_UINT64_FIELD(p, offset) \
+  ReadUnalignedValue<uint64_t>(FIELD_ADDR(p, offset))
+
+#define WRITE_UINT64_FIELD(p, offset, value) \
+  WriteUnalignedValue<uint64_t>(FIELD_ADDR(p, offset), value)
+
+#else  // V8_COMPRESS_POINTERS
+
+#define READ_INTPTR_FIELD(p, offset) \
+  (*reinterpret_cast<const intptr_t*>(FIELD_ADDR(p, offset)))
+
+#define WRITE_INTPTR_FIELD(p, offset, value) \
+  (*reinterpret_cast<intptr_t*>(FIELD_ADDR(p, offset)) = value)
+
+#define READ_UINTPTR_FIELD(p, offset) \
+  (*reinterpret_cast<const uintptr_t*>(FIELD_ADDR(p, offset)))
+
+#define WRITE_UINTPTR_FIELD(p, offset, value) \
+  (*reinterpret_cast<uintptr_t*>(FIELD_ADDR(p, offset)) = value)
+
 #define READ_UINT64_FIELD(p, offset) \
   (*reinterpret_cast<const uint64_t*>(FIELD_ADDR(p, offset)))
 
 #define WRITE_UINT64_FIELD(p, offset, value) \
   (*reinterpret_cast<uint64_t*>(FIELD_ADDR(p, offset)) = value)
 
-#define READ_INT64_FIELD(p, offset) \
-  (*reinterpret_cast<const int64_t*>(FIELD_ADDR(p, offset)))
-
-#define WRITE_INT64_FIELD(p, offset, value) \
-  (*reinterpret_cast<int64_t*>(FIELD_ADDR(p, offset)) = value)
+#endif  // V8_COMPRESS_POINTERS
 
 #define READ_BYTE_FIELD(p, offset) \
   (*reinterpret_cast<const byte*>(FIELD_ADDR(p, offset)))