[llvm] [nfc][docs]Generalize header and ascii art for indexed profiles (PR #83507)

[Mingming Liu via llvm-commits]

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@@ -369,55 +373,45 @@ General Storage Layout
                             +-----------------------+   |
                             |        HashType       |   H
                             +-----------------------+   E
-                    +-------|       HashOffset      |   A
-                    |       +-----------------------+   D
-                +-----------|     MemProfOffset     |   E
-                |   |       +-----------------------+   R
-                |   |    +--|     BinaryIdOffset    |   |
-                |   |    |  +-----------------------+   |
-            +---------------|      TemporalProf-    |   |
-            |   |   |    |  |      TracesOffset     |   |
-            |   |   |    |  +-----------------------+---+
-            |   |   |    |  |   Profile Summary     |   |
-            |   |   |    |  +-----------------------+   P
-            |   |   +------>|    Function data      |   A
-            |   |        |  +-----------------------+   Y
-            |   +---------->|  MemProf profile data |   L
-            |            |  +-----------------------+   O
-            |            +->|    Binary Ids         |   A
+                            |       Byte Offset     |   A
+                    +------ |      of section 2     |   D
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minglotus-6 wrote:

Profile summary is regarded as the first payload section and it doesn't need an offset.

I revised the graph to use section A B ... Z, and added a note to mention profile summary.

https://github.com/llvm/llvm-project/pull/83507