[compiler-rt] [llvm] [docs][IRPGO]Document two binary formats for instrumentation-based profiles, with a focus on IRPGO. (PR #76105)

[Fangrui Song via llvm-commits]

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@@ -58,6 +58,7 @@ intermediate LLVM representation.
    NVPTXUsage
    Phabricator
    Passes
+   InstrProfileFormat
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MaskRay wrote:

This is alphabetically ordered.

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