[compiler-rt] [scudo] Add hooks to mark the range of realloc (PR #73883)

[via llvm-commits]

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@@ -163,23 +208,11 @@ INTERFACE WEAK void *SCUDO_PREFIX(pvalloc)(size_t size) {
 }
 
 INTERFACE WEAK void *SCUDO_PREFIX(realloc)(void *ptr, size_t size) {
-  if (!ptr) {
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ChiaHungDuan wrote:

I wound't say there's the contract `always __scudo_realloc_begin_hook followed by __scudo_deallocate_hook followed by __scudo_allocate_hook followed by __scudo_realloc_end_hook` BTW. It's still reasonable to do it in old way but with the scope markers. To me, it says the begin/end for realloc, covering the whole range then it does let the user doesn't need to second-guess what the intent is.

But like I said, no strong opinion here. Will change it to the form desired

https://github.com/llvm/llvm-project/pull/73883