[compiler-rt] [scudo] Add partial chunk heuristic to retrieval algorithm. (PR #105009)

[Christopher Ferris via llvm-commits]

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@@ -659,8 +721,18 @@ MapAllocator<Config>::tryAllocateFromCache(const Options &Options, uptr Size,
                                            FillContentsMode FillContents) {
   CachedBlock Entry;
   uptr EntryHeaderPos;
+  uptr MaxAllowedFragmentedPages;
+
+  if (LIKELY(!useMemoryTagging<Config>(Options))) {
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cferris1000 wrote:

I realized you can simplify this even more:

  uptr MaxAllowedFragmentedPages = MaxUnreleasedCachePages;
  if (UNLIKELY(useMemoryTagging...)
     MaxAllowedFragmentedPages += CachedBlock::MaxReleasedCachePages;

https://github.com/llvm/llvm-project/pull/105009