[compiler-rt] [rtsan] Add Support for Realtime Sanitizer for SystemZ (PR #165259)

[Chris Apple via llvm-commits]

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@@ -45,11 +45,23 @@ uptr internal_mmap(void *addr, uptr length, int prot, int flags, int fd,
     (unsigned long)(offset / 4096),
 #  endif
   };
+  // Realtime Sanitizer syscall calls interceptor during initializatio at the
+  // time when inceptors are not even intialized.
+  // We have an option of modifying implementation of  internal_mmap for s390
+  // in sanitizer_linux.cpp.
+  register uptr retval __asm__("r2");
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cjappl wrote:

Currently we are working on a branch where we fix this issue. It may be wise to hold off on submitting this until we put that in so we don't need to change this file.

CC @davidtrevelyan 

https://github.com/llvm/llvm-project/pull/165259