[compiler-rt] [compiler-rt][ctx_profile] Add the instrumented contextual profiling APIs (PR #89838)

[Snehasish Kumar via llvm-commits]

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@@ -38,3 +131,181 @@ void Arena::freeArenaList(Arena *&A) {
   }
   A = nullptr;
 }
+
+inline ContextNode *ContextNode::alloc(char *Place, GUID Guid,
+                                       uint32_t NrCounters,
+                                       uint32_t NrCallsites,
+                                       ContextNode *Next) {
+  assert(reinterpret_cast<uint64_t>(Place) % sizeof(void *) == 0);
+  return new (Place) ContextNode(Guid, NrCounters, NrCallsites, Next);
+}
+
+void ContextNode::reset() {
+  for (uint32_t I = 0; I < NrCounters; ++I)
+    counters()[I] = 0;
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snehasish wrote:

Sounds good. I don't think the compiler will be able to reason through the counters() implementation to be able to do this automatically though. 

https://github.com/llvm/llvm-project/pull/89838