[compiler-rt] [asan][sanitizer_common][AIX] Set allocator size and beginning (PR #144784)

[Jake Egan via llvm-commits]

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@@ -288,6 +288,7 @@ class SizeClassAllocator32 {
   uptr ComputeRegionId(uptr mem) const {
     if (SANITIZER_SIGN_EXTENDED_ADDRESSES)
       mem &= (kSpaceSize - 1);
+    mem -= kSpaceBeg;
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jakeegan wrote:

On 64-bit AIX, SizeClassAllocator64 is used (`SANITIZER_CAN_USE_ALLOCATOR64=1`), but the internal primary allocator is SizeClassAllocator32. 

https://github.com/llvm/llvm-project/pull/144784