[compiler-rt] [AArch64][compiler-rt] Add memcpy, memset, memmove, memchr builtins. (PR #77496)

[Peter Waller via llvm-commits]

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@@ -0,0 +1,87 @@
+#include <stdlib.h>
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peterwaller-arm wrote:

I've #79454 to switch this out for `stddef.h` which is provided by the compiler resource headers rather than the libc (since this is inside builtins).

https://github.com/llvm/llvm-project/pull/77496