[compiler-rt] Dump regs fbsd fix (PR #99676)

[Vitaly Buka via llvm-commits]

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@@ -2232,8 +2236,35 @@ void SignalContext::DumpAllRegisters(void *context) {
   DumpSingleReg(ucontext, REG_EBP);
   DumpSingleReg(ucontext, REG_ESP);
   Printf("\n");
+#    else
+  (void)ucontext;
 #    endif
+#  elif SANITIZER_FREEBSD
+#    if defined(__x86_64__)
+  Report("Register values:\n");
+  Printf("RAX = 0x%016llx  ", ucontext->uc_mcontext.mc_rax);
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vitalybuka wrote:

maybe helper:
`static void DumpSingleReg(const char* Name, uptr Value)`

https://github.com/llvm/llvm-project/pull/99676