[compiler-rt] [NFC][Sanitizer] Refine the restriction on SizeClassAllocator64::kRegionSize (PR #86270)

[via llvm-commits]

https://github.com/Enna1 created https://github.com/llvm/llvm-project/pull/86270

This patch replaces the `SANITIZER_WORDSIZE / 2` with `sizeof(CompactPtrT) * 8`, replaces hardcoded `4` with `kCompactPtrScale` in assertion.

>From 317684b4fa139ca07a6642b813b7e67b0c53b6f2 Mon Sep 17 00:00:00 2001
From: "xumingjie.enna1" <xumingjie.enna1 at bytedance.com>
Date: Fri, 22 Mar 2024 17:59:59 +0800
Subject: [PATCH] [NFC][Sanitizer] Refine the restriction on
 SizeClassAllocator64::kRegionSize

---
 .../lib/sanitizer_common/sanitizer_allocator_primary64.h       | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary64.h b/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary64.h
index 34a64f26478fd5..6e73065d7f53c5 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary64.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary64.h
@@ -639,7 +639,8 @@ class SizeClassAllocator64 {
   static_assert(kRegionSize >= SizeClassMap::kMaxSize,
                 "Region size exceed largest size");
   // kRegionSize must be <= 2^36, see CompactPtrT.
-  COMPILER_CHECK((kRegionSize) <= (1ULL << (SANITIZER_WORDSIZE / 2 + 4)));
+  COMPILER_CHECK((kRegionSize) <=
+                 (1ULL << (sizeof(CompactPtrT) * 8 + kCompactPtrScale)));
   // Call mmap for user memory with at least this size.
   static const uptr kUserMapSize = 1 << 18;
   // Call mmap for metadata memory with at least this size.