[clang] [llvm] [InstrProf] Fix frontend generated function hash (PR #165358)

[Ellis Hoag via cfe-commits]

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@@ -734,7 +734,7 @@ void FuncPGOInstrumentation<Edge, BBInfo>::computeCFGHash() {
   FunctionHash = (((uint64_t)JCH.getCRC()) << 28) + JC.getCRC();
 
   // Reserve bit 60-63 for other information purpose.
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ellishg wrote:

Let's move this comment to the definition of `FUNC_HASH_MASK`

https://github.com/llvm/llvm-project/pull/165358