[compiler-rt] 9971269 - [sanitizer] Relax the restriction on SizeClassAllocator64::kAllocatorSize

[Fangrui Song via llvm-commits]

Author: Fangrui Song
Date: 2023-06-27T19:47:03-07:00
New Revision: 9971269ea72aeedc26718522e7e0682f79b63b6c

URL: https://github.com/llvm/llvm-project/commit/9971269ea72aeedc26718522e7e0682f79b63b6c
DIFF: https://github.com/llvm/llvm-project/commit/9971269ea72aeedc26718522e7e0682f79b63b6c.diff

LOG: [sanitizer] Relax the restriction on SizeClassAllocator64::kAllocatorSize

Commit 278ccdacdcbde3399f1fa4b3ab929212e4e0322c says that kAllocatorSize
must be >= (1<<32), but this is not accurate. This static_assert causes 128GiB
kAllocatorSize to be unable to select DefaultSizeClassMap (kRegionSize is
1<<31).

Relax the restriction to be able to satisfy the largest size class. This allows
DefaultSizeClassMap to be usable with 128GiB kAllocatorSize, with
check-{asan,lsan,sanitizer} passing.

Reviewed By: #sanitizers, vitalybuka, kstoimenov

Differential Revision: https://reviews.llvm.org/D153664

Added: 
    

Modified: 
    compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary64.h

Removed: 
    


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diff  --git a/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary64.h b/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary64.h
index 66ba71d325dad..fa43ac50c61e4 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary64.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_allocator_primary64.h
@@ -635,8 +635,8 @@ class SizeClassAllocator64 {
     return kUsingConstantSpaceBeg ? kSpaceBeg : NonConstSpaceBeg;
   }
   uptr SpaceEnd() const { return  SpaceBeg() + kSpaceSize; }
-  // kRegionSize must be >= 2^32.
-  COMPILER_CHECK((kRegionSize) >= (1ULL << (SANITIZER_WORDSIZE / 2)));
+  // kRegionSize should be able to satisfy the largest size class.
+  static_assert(kRegionSize >= SizeClassMap::kMaxSize);
   // kRegionSize must be <= 2^36, see CompactPtrT.
   COMPILER_CHECK((kRegionSize) <= (1ULL << (SANITIZER_WORDSIZE / 2 + 4)));
   // Call mmap for user memory with at least this size.