[llvm] Add initial support for SPE brstack format (PR #129231)

[Ádám Kallai via llvm-commits]

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@@ -175,11 +180,16 @@ void DataAggregator::start() {
 
   findPerfExecutable();
 
-  if (opts::BasicAggregation) {
-    launchPerfProcess("events without LBR",
-                      MainEventsPPI,
+  if (opts::ArmSPE) {
+    // pid    from_ip      to_ip        predicted/missed not-taken?
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kaadam wrote:

Added the suggested details.

https://github.com/llvm/llvm-project/pull/129231