[compiler-rt] [llvm] [TypeProf][InstrPGO] Introduce raw and instr profile format change for type profiling. (PR #81691)

[Snehasish Kumar via llvm-commits]

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@@ -71,6 +75,19 @@ uint64_t __llvm_profile_get_data_size(const __llvm_profile_data *Begin,
   return __llvm_profile_get_num_data(Begin, End) * sizeof(__llvm_profile_data);
 }
 
+COMPILER_RT_VISIBILITY
+uint64_t __llvm_profile_get_num_vtable(const VTableProfData *Begin,
+                                       const VTableProfData *End) {
+  intptr_t EndI = (intptr_t)End, BeginI = (intptr_t)Begin;
+  return (EndI + sizeof(VTableProfData) - 1 - BeginI) / sizeof(VTableProfData);
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snehasish wrote:

I don't follow the math for the numerator. Can you add a comment to explain?

https://github.com/llvm/llvm-project/pull/81691