[compiler-rt] [llvm] [docs][IRPGO]Document two binary formats for IRPGO profiles (PR #76105)

[David Li via llvm-commits]

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+===================================
+Instrumentation PGO Profile Format
+===================================
+
+.. contents::
+   :local:
+
+
+Overview
+=========
+
+Instrumentation PGO inserts `llvm.instrprof.*` `code generator intrinsics`_
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david-xl wrote:

Probably referencing https://clang.llvm.org/docs/UsersManual.html#profiling-with-instrumentation for background.

https://github.com/llvm/llvm-project/pull/76105