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

[via llvm-commits]

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@@ -659,8 +712,20 @@ MapAllocator<Config>::tryAllocateFromCache(const Options &Options, uptr Size,
                                            FillContentsMode FillContents) {
   CachedBlock Entry;
   uptr EntryHeaderPos;
+  uptr MaxAllowedFragmentedBytes;
+  const uptr PageSize = getPageSizeCached();
+
+  if (LIKELY(!useMemoryTagging<Config>(Options))) {
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ChiaHungDuan wrote:

How about let's change all the bytes to pages? It'll be `MaxAllowedFragmentedPages` and determine the bytes right before `releaseAndZeroPagesToOS()`.

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