[PATCH] D38245: [Sanitizers] Allocator: new "release memory to OS" implementation

[Evgenii Stepanov via Phabricator via llvm-commits]

eugenis added a comment.

Why are you mapping the counters in a specific place just after the free array, instead of simply anywhere? I.e. why MAP_FIXED at all?



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Comment at: lib/sanitizer_common/sanitizer_allocator_primary64.h:317
+      counter_size_bits_log = Log2(counter_size_bits);
+      counter_mask = UINT64_MAX >> (sizeof(*buffer) * 8ULL - counter_size_bits);
+
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Either use a named constant instead of UINT64_MAX, or use 8 instead of sizeof(*buffer).


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Comment at: lib/sanitizer_common/sanitizer_allocator_primary64.h:772
+    ThisT* const allocator;
+    RegionInfo* const region;
+    const uptr region_base;
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These are const pointers to mutable objects. What's the point?



https://reviews.llvm.org/D38245