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

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-compiler-rt-sanitizer

Author: Enna1 (Enna1)

<details>
<summary>Changes</summary>

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

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Full diff: https://github.com/llvm/llvm-project/pull/86270.diff


1 Files Affected:

- (modified) compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary64.h (+2-1) 


``````````diff
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.

``````````

</details>


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