[llvm] [llvm-exegesis] Add explicit error message with segfault address (PR #74210)

[Clement Courbet via llvm-commits]

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@@ -41,14 +43,19 @@ class ClusteringError : public ErrorInfo<ClusteringError> {
 class SnippetCrash : public ErrorInfo<SnippetCrash> {
 public:
   static char ID;
-  SnippetCrash(const Twine &S) : Msg(S.str()) {}
+  SnippetCrash(const Twine &S)
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legrosbuffle wrote:

> https://github.com/llvm/llvm-project/pull/74211 adds additional support (including a getter). https://github.com/google/gematria/pull/30 shows the usage on top of that PR.

Thanks for the pointers. With the added getter in #74211 I think we should probably have two different types, because the getter would be meaningless in case of a failed child process without a crash. In particular, l137 in https://github.com/google/gematria/pull/30 would be incorrect. WDYT ?

https://github.com/llvm/llvm-project/pull/74210